* { box-sizing: border-box; }
:root {
  --navy: #172033;
  --blue: #3867e8;
  --green: #23853b;
  --amber: #b56b00;
  --red: #a82c2c;
  --purple: #6d46c8;
  --background: #f2f4f8;
  --border: #d6dce6;
  --muted: #5d6675;
}
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: var(--background);
  color: var(--navy);
}
button, input, textarea, select { font: inherit; }
button {
  border: 0;
  border-radius: 10px;
  padding: 12px 18px;
  background: var(--blue);
  color: white;
  font-weight: 700;
  cursor: pointer;
}
button:hover { filter: brightness(.96); }
button:disabled { opacity: .55; cursor: not-allowed; }
.secondary { background: #e5e9f0; color: var(--navy); }
.success-button { background: var(--green); }
.warning-button { background: #f1a51f; color: #241800; }
.visualise-button { background: var(--purple); }
.save-button { background: #167f73; }
.small { padding: 9px 12px; }
.hidden { display: none !important; }
.topbar {
  background: var(--navy);
  color: white;
  padding: 18px max(18px, calc((100vw - 1180px) / 2));
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}
.topbar h1 { margin: 0; font-size: 1.75rem; }
.topbar p { margin: 4px 0 0; opacity: .82; }
.signed-in-controls { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; justify-content: flex-end; }
.page-shell { width: min(1180px, calc(100% - 28px)); margin: 22px auto 50px; }
.card {
  background: white;
  border: 1px solid #e3e7ee;
  border-radius: 16px;
  padding: 22px;
  box-shadow: 0 5px 18px rgba(27, 38, 61, .07);
  margin-bottom: 18px;
}
.hero { margin-bottom: 18px; }
.hero h2, .card h2, .card h3 { margin-top: 0; }
.auth-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; align-items: start; }
.google-button { width: 100%; background: white; color: #263142; border: 2px solid var(--border); }

.auth-divider { display: flex; align-items: center; gap: 10px; margin: 16px 0; color: #697386; font-size: .9rem; }
.auth-divider::before, .auth-divider::after { content: ""; flex: 1; height: 1px; background: var(--border); }
.auth-divider span { white-space: nowrap; }
.auth-help-button { display: block; margin: 12px auto 0; }
.pupil-auth-card .google-button { margin-top: 4px; }
label { display: block; font-weight: 700; margin: 13px 0; }
input,
select {
  display: block;
  width: 100%;
  min-width: 0;
  margin-top: 6px;
  border: 2px solid var(--border);
  border-radius: 9px;
  padding: 12px;
  background: white;
  color: var(--navy);
}
select { min-height: 48px; }
input:focus, textarea:focus, select:focus { outline: 3px solid rgba(56, 103, 232, .18); border-color: var(--blue); }
form > button[type="submit"] { width: 100%; margin-top: 8px; }
.help-text { color: var(--muted); font-size: .92rem; }
.tab-row { display: flex; gap: 8px; margin-bottom: 14px; }
.tab { flex: 1; background: #e9edf4; color: var(--navy); }
.tab.active { background: var(--navy); color: white; }
.message { padding: 13px 16px; border-radius: 10px; margin-bottom: 16px; font-weight: 700; }
.message.info { background: #e4edff; color: #1f4aa8; }
.message.success { background: #daf5e1; color: #17632c; }
.message.error { background: #ffe1e1; color: #8e2020; }
.dashboard-heading, .panel-heading, .challenge-heading, .editor-heading {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 15px;
  margin-bottom: 18px;
}
.dashboard-heading h2, .dashboard-heading p, .panel-heading h3, .panel-heading p { margin: 0 0 5px; }
.inline-form { display: grid; grid-template-columns: 1fr auto auto; gap: 10px; align-items: end; }
.inline-form label { margin: 0; }
.inline-form button { margin-bottom: 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin: 18px 0; }
.stats-grid.compact { grid-template-columns: repeat(3, 1fr); }
.stat-card { background: white; border-radius: 14px; padding: 17px; border: 1px solid #e1e6ee; }
.stat-value { font-size: 1.65rem; font-weight: 800; display: block; margin-bottom: 4px; }
.stat-label { color: var(--muted); }
.class-grid, .task-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.class-card, .task-card { background: white; border-radius: 14px; padding: 19px; border: 1px solid #e1e6ee; box-shadow: 0 4px 12px rgba(27,38,61,.05); }
.class-card h3, .task-card h3 { margin: 0 0 8px; }
.code-chip { display: inline-block; font-family: Consolas, monospace; font-weight: 800; letter-spacing: 2px; padding: 7px 10px; background: #eef2f8; border-radius: 8px; }
.card-actions { display: flex; gap: 10px; align-items: center; margin-top: 14px; flex-wrap: wrap; }
.progress-bar { height: 10px; background: #e7ebf1; border-radius: 999px; overflow: hidden; margin: 12px 0; }
.progress-bar > span { display: block; height: 100%; background: var(--green); }
.progress-badge { background: white; padding: 12px 16px; border-radius: 12px; font-weight: 800; border: 1px solid #e1e6ee; }
.status-pill { border-radius: 999px; padding: 7px 11px; background: #e6eaf0; font-weight: 800; }
.status-pill.complete { background: #d8f2df; color: #1b6c30; }
.status-pill.working { background: #fff0cd; color: #795000; }
.status-pill.needs-work { background: #ffe1d8; color: #853617; }
.eyebrow { text-transform: uppercase; letter-spacing: .08em; color: var(--blue); font-weight: 800; margin: 0 0 4px; font-size: .82rem; }
.instructions { line-height: 1.55; }
.expected-output { background: #edf1f6; color: var(--navy); padding: 12px; border-radius: 9px; }
textarea {
  width: 100%;
  min-height: 290px;
  padding: 15px;
  border: 2px solid var(--border);
  border-radius: 10px;
  font-family: Consolas, "Courier New", monospace;
  font-size: 16px;
  line-height: 1.5;
  resize: vertical;
  tab-size: 4;
}
.button-row { display: grid; gap: 10px; margin-top: 12px; }
.six-buttons { grid-template-columns: repeat(6, 1fr); }
.console {
  min-height: 100px;
  background: #101722;
  color: #e9eff8;
  border-radius: 10px;
  padding: 15px;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.feedback { margin-top: 12px; padding: 14px; border-radius: 10px; white-space: pre-line; font-weight: 700; }
.feedback.success { background: #daf5e1; color: #17632c; }
.feedback.error { background: #ffe6d8; color: #7b3410; }
.feedback.info { background: #e4edff; color: #1f4aa8; }
.loading-text { color: var(--muted); font-weight: 700; margin: 0; }
.save-status { color: var(--muted); font-weight: 700; font-size: .92rem; }
.save-status.unsaved { color: var(--amber); }
.save-status.saving { color: var(--blue); }
.save-status.saved { color: var(--green); }
.save-status.error { color: var(--red); }
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { padding: 12px 10px; border-bottom: 1px solid #e4e8ee; text-align: left; }
th { background: #f4f6f9; }
.error-tab-row { display: flex; gap: 8px; margin-bottom: 12px; }
.error-tab { background: #e9edf4; color: var(--navy); }
.error-tab.active { background: var(--navy); color: white; }
.error-console { min-height: 130px; }
.friendly-error {
  border: 1px solid #f0c9b5;
  background: #fff7f1;
  border-radius: 10px;
  padding: 16px;
  white-space: pre-line;
  line-height: 1.55;
}
.visualiser-panel h4 { margin: 0 0 10px; }
.visualiser-controls { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 18px; }
.visualiser-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 18px; margin-bottom: 18px; }
.visualiser-code {
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  background: #fbfcfe;
  font-family: Consolas, "Courier New", monospace;
}
.code-line {
  display: grid;
  grid-template-columns: 3.2rem 1fr;
  min-height: 1.75rem;
  border-bottom: 1px solid #edf0f4;
}
.code-line:last-child { border-bottom: 0; }
.code-line-number {
  padding: 5px 9px;
  text-align: right;
  color: var(--muted);
  background: #eef2f7;
  user-select: none;
}
.code-line-text { padding: 5px 10px; white-space: pre-wrap; overflow-wrap: anywhere; }
.code-line.current .code-line-number { background: #f1a51f; color: #241800; font-weight: 800; }
.code-line.current .code-line-text { background: #fff4cf; font-weight: 700; }
.variables-table td { font-family: Consolas, "Courier New", monospace; }
.variables-table tr.changed td { background: #fff4cf; }
.empty-table { color: var(--muted); font-family: Arial, Helvetica, sans-serif !important; }
.visualiser-output { min-height: 75px; }
footer { text-align: center; color: var(--muted); padding: 20px; font-size: .9rem; }
@media (max-width: 1050px) {
  .six-buttons { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 850px) {
  .auth-grid, .class-grid, .task-grid, .visualiser-grid { grid-template-columns: 1fr; }
  .stats-grid, .stats-grid.compact { grid-template-columns: repeat(2, 1fr); }
  .inline-form { grid-template-columns: 1fr; }
  .six-buttons { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .topbar, .dashboard-heading, .panel-heading, .challenge-heading, .editor-heading { align-items: flex-start; flex-direction: column; }
  .signed-in-controls { justify-content: flex-start; }
  .stats-grid, .stats-grid.compact { grid-template-columns: 1fr; }
  .six-buttons { grid-template-columns: 1fr; }
  .page-shell { width: min(100% - 18px, 1180px); margin-top: 12px; }
  .card { padding: 16px; }
  .error-tab-row { flex-direction: column; }
}

/* Version 4.1 curriculum pathway */
.heading-actions { display: flex; gap: 10px; flex-wrap: wrap; }
.area-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin: 18px 0; }
.area-card { background: white; border: 1px solid #e1e6ee; border-radius: 16px; padding: 20px; min-height: 220px; display: flex; flex-direction: column; }
.area-card h3 { margin: 4px 0 9px; }
.area-card p { line-height: 1.5; }
.area-card .card-actions { margin-top: auto; }
.area-card.coming-soon { background: #f8f9fb; color: var(--muted); }
.area-badge { display: inline-block; width: fit-content; border-radius: 999px; padding: 6px 10px; background: #e9edf4; font-weight: 800; font-size: .85rem; }
.area-card.active-area .area-badge { background: #dce7ff; color: #214ea8; }
.pathway-heading { display: flex; justify-content: space-between; gap: 20px; align-items: center; }
.pathway-heading h3 { margin: 2px 0 7px; }
.unit-list { display: grid; gap: 16px; }
.unit-card { background: white; border: 1px solid #e1e6ee; border-radius: 16px; overflow: hidden; box-shadow: 0 4px 12px rgba(27,38,61,.05); }
.unit-header { display: grid; grid-template-columns: auto 1fr auto; gap: 15px; align-items: center; padding: 18px 20px; background: #fafbfc; border-bottom: 1px solid #e8ebf0; }
.unit-number { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 50%; background: var(--navy); color: white; font-weight: 800; }
.unit-title h3 { margin: 0 0 4px; }
.unit-title p { margin: 0; color: var(--muted); }
.unit-progress { min-width: 150px; text-align: right; font-weight: 700; }
.activity-list { list-style: none; padding: 0; margin: 0; }
.activity-row { display: grid; grid-template-columns: 42px minmax(0, 1fr) auto; gap: 13px; align-items: center; padding: 14px 20px; border-bottom: 1px solid #edf0f4; }
.activity-row:last-child { border-bottom: 0; }
.activity-row.locked { opacity: .62; background: #fafafa; }
.activity-row.optional { background: #fbfcff; }
.activity-order { font-weight: 800; color: var(--muted); }
.activity-main h4 { margin: 0 0 4px; }
.activity-main p { margin: 0; color: var(--muted); font-size: .92rem; }
.activity-meta { display: flex; gap: 7px; flex-wrap: wrap; margin-top: 7px; }
.activity-chip, .mark-chip { display: inline-block; padding: 4px 8px; border-radius: 999px; background: #edf1f6; color: #354155; font-size: .78rem; font-weight: 800; }
.activity-chip.optional { background: #eee7ff; color: #5c3ca5; }
.activity-status-icon { width: 30px; text-align: center; font-size: 1.15rem; }
.activity-row button { min-width: 110px; }
.activity-card { margin-top: 16px; }
.lesson-code { background: #101722; color: #e9eff8; border-radius: 10px; padding: 14px; white-space: pre-wrap; font-family: Consolas, "Courier New", monospace; }
.video-frame { width: 100%; aspect-ratio: 16 / 9; border: 0; border-radius: 12px; background: #101722; margin: 12px 0; }
.video-placeholder { border: 2px dashed var(--border); background: #f8fafc; border-radius: 12px; padding: 22px; margin: 14px 0; }
.activity-question { border-top: 1px solid #e3e7ee; padding-top: 17px; margin-top: 17px; }
.question-block { margin: 0 0 20px; padding: 16px; border: 1px solid #e1e6ee; border-radius: 12px; background: #fbfcfe; }
.question-block legend { font-weight: 800; padding: 0 4px; }
.option-label { display: flex; gap: 9px; align-items: flex-start; font-weight: 400; margin: 10px 0; }
.option-label input { width: auto; margin: 3px 0 0; }
.activity-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
.written-response { min-height: 150px; font-family: Arial, Helvetica, sans-serif; }
.marking-points { background: #eef7f0; border: 1px solid #cde7d2; border-radius: 12px; padding: 16px; margin-top: 15px; }
.marking-points ul { margin-bottom: 0; }
.official-paper-box { border-left: 5px solid var(--purple); background: #f7f3ff; border-radius: 10px; padding: 17px; }
.official-paper-box h3 { margin-top: 0; }
.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
.related-item { border: 1px solid #e1e6ee; border-radius: 12px; padding: 15px; }
.related-item h4 { margin: 0 0 7px; }
.sample-input-note { background: #eaf4ff; border-radius: 9px; padding: 11px 13px; color: #244d80; }
.content-form { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px 14px; }
.content-form label { margin: 0; }
.content-form select { display: block; width: 100%; margin-top: 6px; border: 2px solid var(--border); border-radius: 9px; padding: 12px; background: white; }
.wide-field { grid-column: 1 / -1; }
.small-textarea { min-height: 95px; font-family: Arial, Helvetica, sans-serif; }
.checkbox-label { display: flex; gap: 9px; align-items: center; font-weight: 700; margin-top: 22px !important; }
.checkbox-label input { width: auto; margin: 0; }
.content-form-actions { display: flex; gap: 10px; }
.content-list { display: grid; gap: 10px; }
.content-item { border: 1px solid #e1e6ee; border-radius: 12px; padding: 15px; display: flex; justify-content: space-between; gap: 14px; align-items: center; }
.content-item h5 { margin: 0 0 5px; font-size: 1rem; }
.content-item p { margin: 0; color: var(--muted); }
.content-item-actions { display: flex; gap: 7px; flex-wrap: wrap; }
.danger-button { background: var(--red); }

@media (max-width: 950px) {
  .area-grid { grid-template-columns: 1fr; }
  .content-form { grid-template-columns: 1fr 1fr; }
  .wide-field { grid-column: 1 / -1; }
}
@media (max-width: 700px) {
  .pathway-heading, .content-item { align-items: flex-start; flex-direction: column; }
  .unit-header { grid-template-columns: auto 1fr; }
  .unit-progress { grid-column: 1 / -1; text-align: left; }
  .activity-row { grid-template-columns: 34px 1fr; }
  .activity-row button { grid-column: 1 / -1; width: 100%; }
  .related-grid { grid-template-columns: 1fr; }
  .content-form { grid-template-columns: 1fr; }
  .wide-field { grid-column: auto; }
}
.button-link { display: inline-block; border-radius: 10px; padding: 12px 18px; background: var(--blue); color: white; font-weight: 700; text-decoration: none; }
.button-link:hover { filter: brightness(.96); }


/* v4.1.4 exam-answer workspace */
.exam-answer-workspace {
  margin-top: 20px;
  border-top: 1px solid #d7dde8;
  padding-top: 20px;
}

.workspace-heading,
.subsection-heading,
.response-summary-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.official-response {
  min-height: 220px;
  margin-top: 10px;
}

.submission-note {
  margin-top: 10px;
  padding: 12px 14px;
  border-radius: 10px;
  background: #eef3ff;
  color: #25365f;
}

.model-answer-panel {
  margin-top: 18px;
}

.model-answer-text,
.response-text {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  padding: 14px;
  border: 1px solid #d7dde8;
  border-radius: 10px;
  background: #f7f9fc;
  min-height: 70px;
}

.self-review-grid,
.response-review-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin: 18px 0;
}

.self-review-grid .wide-field {
  grid-column: 1 / -1;
}

.paper-response-viewer {
  margin-top: 18px;
  padding: 18px;
  border: 1px solid #d7dde8;
  border-radius: 12px;
  background: #fbfcfe;
}

.response-summary-row {
  margin: 16px 0;
  padding: 12px 0;
  border-top: 1px solid #d7dde8;
  border-bottom: 1px solid #d7dde8;
}

@media (max-width: 700px) {
  .self-review-grid,
  .response-review-grid {
    grid-template-columns: 1fr;
  }
}


/* v4.1.5 question-specific written-answer guidance */
.answer-quality-tip {
  margin: 0 0 18px;
  padding: 15px 17px;
  border: 1px solid #cdd8ff;
  border-left: 5px solid var(--accent);
  border-radius: 12px;
  background: #f4f6ff;
}

.answer-quality-tip strong {
  display: block;
  margin-bottom: 8px;
}

.answer-quality-tip ol {
  margin: 0 0 8px 22px;
  padding: 0;
}

.answer-quality-tip li {
  margin: 5px 0;
}

.answer-quality-tip p,
.model-answer-note {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: .92rem;
}

.model-answer-note {
  margin-bottom: 10px;
}


/* v4.2 personalised spaced learning */
.spaced-practice-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 24px;
  border-left: 6px solid var(--accent);
}

.spaced-practice-card h3,
.spaced-practice-card p { margin-top: 0; }

.spaced-session-card { margin-top: 18px; }

.spaced-explanation-grid,
.spaced-summary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  margin: 20px 0;
}

.spaced-explanation-grid > div,
.spaced-summary-grid > section {
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #f8fafc;
}

.spaced-explanation-grid p { margin-bottom: 0; }

#spacedQuestionPanel label > select {
  max-width: 260px;
  margin-top: 8px;
}

.spaced-result-hero {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 20px;
  margin: 18px 0;
  border-radius: 14px;
  background: #eef2ff;
}

.spaced-result-score {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--accent);
}

.spaced-summary-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.model-answer-text strong { color: #172554; }

@media (max-width: 760px) {
  .spaced-practice-card { align-items: stretch; flex-direction: column; }
  .spaced-explanation-grid,
  .spaced-summary-grid { grid-template-columns: 1fr; }
}


/* v4.3 countdown, interleaving and peer marking */
.spaced-countdown { margin: 10px 0 0; font-weight: 700; color: var(--accent); }
.spaced-question-meta, .activity-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-bottom: 14px; }
.area-badge { display: inline-flex; align-items: center; justify-content: center; min-width: 46px; padding: 6px 10px; border-radius: 999px; font-weight: 800; letter-spacing: .04em; }
.area-sdd { background: #e9efff; color: #2648c7; }
.area-ddd { background: #e3f7ed; color: #12633d; }
.area-cs { background: #fff0df; color: #8a4b08; }
.reason-chip { font-weight: 700; }
.area-result-grid, .area-recall-grid { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 12px; margin: 16px 0; }
.area-result-card, .area-recall-card { border: 1px solid var(--border); border-radius: 14px; padding: 14px; display: grid; gap: 7px; background: var(--surface); }
.area-result-card strong, .area-recall-card strong { font-size: 1.35rem; }
.class-focus-panel {
  margin: 20px 0;
  padding: 18px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: #f8f9fd;
}
.class-focus-panel h4 { margin: 0 0 4px; }
.class-focus-intro { margin-bottom: 16px; max-width: 760px; }
.class-focus-intro p { margin-bottom: 0; }
.class-focus-controls {
  display: grid;
  grid-template-columns: minmax(240px, 1.35fr) minmax(210px, 1fr) minmax(220px, .9fr) minmax(150px, auto);
  gap: 14px;
  align-items: start;
}
.class-focus-controls label { margin: 0; min-width: 0; }
.class-focus-controls .focus-help { display: block; margin-top: 8px; line-height: 1.35; }
.class-focus-action {
  display: grid;
  gap: 8px;
  align-content: start;
  padding-top: 29px;
}
.class-focus-action button { width: 100%; min-height: 48px; white-space: nowrap; }
.class-focus-action .help-text { min-height: 1.2em; }
.peer-marking-card { display: flex; align-items: center; justify-content: space-between; gap: 20px; border-left: 6px solid var(--accent); }
.peer-review-workspace { margin-top: 18px; }
.peer-instructions { background: #f3f5ff; border-left: 5px solid var(--accent); padding: 12px 15px; border-radius: 10px; }
.peer-review-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 16px; margin: 18px 0; }
.token-highlight-box { white-space: pre-wrap; line-height: 2.15; min-height: 130px; padding: 16px; border: 1px solid var(--border); border-radius: 12px; background: var(--surface); }
.highlight-token { display: inline; border: 0; background: transparent; color: inherit; padding: 2px 1px; margin: 0; border-radius: 4px; font: inherit; line-height: inherit; cursor: pointer; }
.highlight-token:hover { outline: 1px dashed var(--accent); }
.highlight-token.selected.green, .peer-mark-green { background: #bcebcf; color: #123c23; }
.highlight-token.selected.red, .peer-mark-red { background: #ffc9c9; color: #671b1b; }
.peer-point { display: flex; gap: 9px; align-items: flex-start; margin: 10px 0; }
.peer-mark-controls { display: flex; flex-wrap: wrap; align-items: end; gap: 12px; margin-top: 18px; }
.peer-status-panel, .peer-result-panel { margin-top: 18px; padding: 16px; border: 1px solid #cdd8ff; border-radius: 13px; background: #f5f7ff; }
.peer-choice-actions { margin-top: 15px; }
.peer-result-panel mark { padding: 1px 2px; border-radius: 3px; }
#finalMarkChooser { display: flex; align-items: end; gap: 10px; margin-top: 12px; }
@media (max-width: 820px) {
  .class-focus-controls, .peer-review-grid, .area-result-grid, .area-recall-grid { grid-template-columns: 1fr; }
  .class-focus-action { padding-top: 0; }
  .class-focus-action button { width: auto; justify-self: start; }
  .peer-marking-card { align-items: stretch; flex-direction: column; }
}


/* v4.3.3 design representations and spaced-practice diagrams */
.representation-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 16px;
  margin: 18px 0;
}

.representation-card {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
  background: #f8faff;
}

.representation-card h4 { margin: 0 0 12px; }
.design-svg,
.spaced-design-svg {
  display: block;
  width: 100%;
  max-width: 680px;
  height: auto;
  margin: 12px auto;
  font-family: inherit;
  font-size: 14px;
}
.wide-design-svg { max-width: 760px; }

.flow-start-end { fill: #eef2ff; stroke: #5068e8; stroke-width: 2; }
.flow-input-output { fill: #eefaf6; stroke: #2f8a76; stroke-width: 2; }
.flow-process { fill: #fff7e9; stroke: #bd741c; stroke-width: 2; }
.flow-decision { fill: #fff0f4; stroke: #bb4864; stroke-width: 2; }
.flow-line,
.structure-line { stroke: #27324a; stroke-width: 2; fill: none; }
.flow-arrow { fill: #27324a; }
.structure-node-main { fill: #eaf0ff; stroke: #5068e8; stroke-width: 2; }
.structure-node { fill: #f5f7fb; stroke: #596579; stroke-width: 2; }

.spaced-diagram {
  margin-bottom: 18px;
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: #fff;
  overflow-x: auto;
}

.symbol-choice-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(100px, 1fr));
  gap: 14px;
  max-width: 520px;
  margin: 0 auto;
  text-align: center;
  font-weight: 800;
}
.symbol-choice-row > div {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 10px;
  background: #f8faff;
}
.symbol-svg { width: 100%; max-width: 120px; height: auto; display: block; margin: 0 auto 4px; }

@media (max-width: 620px) {
  .symbol-choice-row { grid-template-columns: 1fr; }
}


/* v4.4 teacher insights, flags, pupil profiles and mastery heatmap */
.teacher-insights-heading { margin-top: 30px; }
.class-focus-panel input,
.class-focus-panel select { margin-top: 6px; }
@media (max-width: 1080px) {
  .class-focus-controls {
    grid-template-columns: repeat(2, minmax(220px, 1fr));
  }
  .class-focus-action { padding-top: 0; align-self: end; }
}

.unit-progress-chart { display: grid; gap: 14px; margin: 14px 0 24px; }
.unit-progress-row { display: grid; grid-template-columns: minmax(210px, .9fr) minmax(260px, 1.5fr); gap: 10px 18px; align-items: center; padding: 14px; border: 1px solid var(--border); border-radius: 14px; background: #fbfcfe; }
.unit-progress-label { display: grid; gap: 4px; }
.unit-progress-label span, .unit-progress-values { color: var(--muted); font-size: .86rem; }
.stacked-progress { height: 18px; display: flex; overflow: hidden; border-radius: 999px; background: #e3e6eb; border: 1px solid #d6dbe4; }
.stacked-progress span { height: 100%; display: block; }
.stack-complete { background: #2f9a4b; }
.stack-developing { background: #e89a24; }
.stack-not-started { background: #d8dce3; }
.unit-progress-values { grid-column: 2; display: flex; gap: 14px; flex-wrap: wrap; }

.attention-list { display: grid; gap: 10px; margin: 14px 0 24px; }
.attention-item { display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; padding: 14px; border: 1px solid var(--border); border-left-width: 6px; border-radius: 13px; background: #fff; }
.attention-item p { margin: 4px 0; }
.attention-danger { border-left-color: #bf3434; background: #fff8f8; }
.attention-warning { border-left-color: #e28c1d; background: #fffaf2; }
.attention-success { border-left-color: #2b9147; background: #f6fff8; }
.attention-badge { width: 30px; height: 30px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-weight: 900; background: #edf0f5; }
.empty-insight-state { padding: 16px; border: 1px dashed var(--border); border-radius: 12px; background: #fafbfc; }
.empty-insight-state p { margin-bottom: 0; }

.text-button { padding: 0; background: transparent; color: var(--navy); border-radius: 3px; text-align: left; text-decoration: underline; text-decoration-color: #aeb8ca; text-underline-offset: 3px; }
.text-button:hover { filter: none; color: var(--blue); }
.heatmap-controls { display: flex; gap: 10px; align-items: end; flex-wrap: wrap; }
.heatmap-controls label { margin: 0; min-width: 160px; }
.heatmap-controls select { width: 100%; }
.heatmap-legend { display: flex; gap: 14px; flex-wrap: wrap; margin: 12px 0; font-size: .9rem; }
.heatmap-legend span { display: inline-flex; align-items: center; gap: 6px; }
.mastery-key, .mastery-inline { display: inline-flex; align-items: center; justify-content: center; border-radius: 7px; font-style: normal; font-weight: 900; }
.mastery-key { width: 27px; height: 27px; }
.mastery-inline { padding: 4px 8px; }
.mastery-green { background: #ccefd5 !important; color: #175c29 !important; }
.mastery-orange { background: #ffe1ad !important; color: #704300 !important; }
.mastery-red { background: #ffd0d0 !important; color: #7f2020 !important; }
.mastery-grey { background: #e4e7ec !important; color: #596273 !important; }
.mastery-heatmap-wrap { overflow: auto; max-height: 620px; border: 1px solid var(--border); border-radius: 14px; background: white; }
.mastery-heatmap { border-collapse: separate; border-spacing: 4px; min-width: 100%; width: max-content; }
.mastery-heatmap th, .mastery-heatmap td { border: 0; padding: 3px; text-align: center; background: transparent; }
.mastery-heatmap th { position: sticky; top: 0; z-index: 3; background: white; min-width: 78px; max-width: 112px; }
.mastery-heatmap th span { display: block; font-size: .76rem; line-height: 1.15; white-space: normal; }
.mastery-heatmap .sticky-pupil-column { position: sticky; left: 0; z-index: 4; min-width: 160px; text-align: left; background: white; box-shadow: 5px 0 8px rgba(23,32,51,.06); }
.mastery-heatmap thead .sticky-pupil-column { z-index: 5; }
.mastery-cell { width: 46px; height: 38px; padding: 0; border-radius: 9px; font-size: 1.05rem; font-weight: 900; }
.mastery-cell:hover { outline: 3px solid rgba(56,103,232,.25); filter: none; }

.skill-insight-viewer, .pupil-insight-panel { margin: 18px 0 26px; padding: 18px; border: 1px solid #cfd6e2; border-radius: 15px; background: #fbfcff; box-shadow: 0 5px 14px rgba(27,38,61,.06); }
.skill-insight-viewer h4, .pupil-insight-panel h4 { margin: 0 0 4px; font-size: 1.35rem; }
.insight-two-column, .pupil-profile-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 16px; }
.profile-section { border: 1px solid var(--border); border-radius: 13px; padding: 15px; background: white; margin-top: 14px; }
.profile-section h5 { margin: 0 0 12px; font-size: 1rem; }
.compact-evidence-list { display: grid; gap: 8px; }
.compact-evidence-list > div { display: flex; justify-content: space-between; gap: 10px; align-items: center; border-bottom: 1px solid #edf0f4; padding-bottom: 7px; }
.review-dot-row { display: flex; gap: 7px; flex-wrap: wrap; align-items: center; }
.review-dot { width: 29px; height: 29px; display: inline-flex; align-items: center; justify-content: center; border-radius: 50%; font-weight: 900; }
.review-dot.correct { background: #ccefd5; color: #175c29; }
.review-dot.incorrect { background: #ffd0d0; color: #7f2020; }
.review-dot-row.large .review-dot { width: 34px; height: 34px; }
.profile-flag-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
.profile-flag { padding: 7px 10px; border-radius: 999px; font-weight: 800; font-size: .88rem; }
.flag-danger { background: #ffd7d7; color: #7c2222; }
.flag-warning { background: #ffe5b9; color: #754500; }
.flag-success { background: #d5f2dc; color: #1c6530; }
.flag-neutral { background: #e6e9ee; color: #556072; }
.pupil-unit-row { display: grid; gap: 6px; margin: 11px 0; }
.pupil-unit-row > div:first-child { display: flex; justify-content: space-between; gap: 12px; }
.pupil-unit-bar { height: 10px; background: #e4e8ee; border-radius: 999px; overflow: hidden; }
.pupil-unit-bar span { display: block; height: 100%; background: #2f9a4b; }
.profile-skill-list { display: grid; gap: 8px; }
.profile-skill-button { display: flex; justify-content: space-between; align-items: center; gap: 10px; width: 100%; padding: 10px 12px; color: var(--navy); text-align: left; }
.profile-skill-button:hover { outline: 2px solid rgba(56,103,232,.2); filter: none; }

@media (max-width: 900px) {
  .class-focus-controls { grid-template-columns: 1fr 1fr; }
  .unit-progress-row { grid-template-columns: 1fr; }
  .unit-progress-values { grid-column: 1; }
  .insight-two-column, .pupil-profile-grid { grid-template-columns: 1fr; }
}
@media (max-width: 620px) {
  .class-focus-controls { grid-template-columns: 1fr; }
  .attention-item { grid-template-columns: auto 1fr; }
  .attention-item button { grid-column: 1 / -1; width: 100%; }
  .mastery-heatmap .sticky-pupil-column { min-width: 125px; }
}


/* v5.0 complete SDD pathway */
.trigger-box { margin: 16px 0; padding: 13px 15px; border-left: 5px solid var(--accent); background: #f4f6ff; border-radius: 10px; }
.concept-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 12px; margin: 16px 0; }
.concept-grid > div { border: 1px solid var(--border); border-radius: 12px; padding: 14px; background: #f8fafc; }
.concept-grid p { margin: 6px 0 0; color: var(--muted); }
.process-strip { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0; }
.process-strip span { padding: 9px 11px; border-radius: 999px; background: #eef2ff; border: 1px solid #c7d2fe; font-weight: 700; }
.coverage-table { width: 100%; border-collapse: collapse; margin: 16px 0; }
.coverage-table th, .coverage-table td { border: 1px solid var(--border); padding: 10px; text-align: left; }
.resource-image { width: 100%; max-height: 1100px; object-fit: contain; border: 1px solid var(--border); border-radius: 14px; background: white; margin: 16px 0; }
@media (max-width: 700px) { .resource-image { max-height: none; } }


/* v5.1 SDD Games Lab */
.games-lab-card { display:flex; justify-content:space-between; align-items:center; gap:24px; background:linear-gradient(135deg,#f5f3ff,#eef8ff); border:1px solid #d9d4ff; }
.game-menu-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:22px; }
.game-menu-card { display:grid; grid-template-columns:auto 1fr; gap:18px; align-items:start; }
.game-menu-card button { grid-column:1 / -1; }
.game-icon { font-size:3rem; line-height:1; }
.debug-menu-card { background:linear-gradient(150deg,#ecfbff,#fff); }
.logic-menu-card { background:linear-gradient(150deg,#fff8df,#fff); }
.game-shell { margin-top:18px; }
.game-setup-panel { display:flex; flex-wrap:wrap; gap:16px; align-items:end; padding:18px; border:1px solid var(--border); border-radius:14px; background:#f7f8fc; }
.game-setup-panel label { min-width:220px; flex:1; }
.preview-notice { padding:12px 15px; border-radius:12px; background:#fff4cc; border:1px solid #e6c75a; color:#6b5000; }
.debug-ocean { position:relative; height:190px; overflow:hidden; border-radius:16px; background:#72d7f5 url("debug-ocean.webp") center/cover no-repeat; margin:18px 0; border:3px solid #bfeeff; }
.debug-ocean img {
  position:absolute;
  top:48%;
  transform:translateY(-50%);
  transition:left .25s linear, top .25s ease-out;
  object-fit:contain;
  will-change:left, top;
}
#debugShark { width:165px; left:7%; }
#debugFish { width:110px; left:80%; }
#debugTimer { position:absolute; top:12px; left:50%; transform:translateX(-50%); padding:7px 13px; border-radius:999px; background:rgba(16,24,44,.86); color:#fff; font-weight:800; }
#debugTimer.urgent { background:#a72020; animation:pulse-timer .75s infinite alternate; }
@keyframes pulse-timer { from { transform:translateX(-50%) scale(1); } to { transform:translateX(-50%) scale(1.08); } }
.debug-stage-grid { display:grid; grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr); gap:18px; }
.game-stage-card { padding:18px; border:1px solid var(--border); border-radius:14px; background:#fff; }
.locked-stage { opacity:.55; pointer-events:none; }
.compact-fieldset { display:flex; flex-wrap:wrap; gap:12px; margin:14px 0; padding:12px; border:1px solid var(--border); border-radius:10px; }
.debug-code-lines { display:flex; flex-direction:column; border:1px solid #cbd4e5; border-radius:10px; overflow:hidden; margin:10px 0 14px; background:#111827; }
.debug-code-line { display:grid; grid-template-columns:38px 1fr; padding:0; border:0; border-radius:0; background:#111827; color:#f8fafc; text-align:left; }
.debug-code-line:hover,.debug-code-line.selected { background:#263b69; }
.debug-code-line span { padding:7px 8px; color:#93a4c5; background:#0b1220; text-align:right; }
.debug-code-line code { padding:7px 10px; white-space:pre-wrap; }
.debug-editor { min-height:260px; font-family:Consolas,"Courier New",monospace; font-size:1rem; tab-size:4; background:#101827; color:#f8fafc; }
.hint-box { margin:10px 0; padding:12px; border-left:4px solid #6d5ce8; background:#f0edff; }
.game-result-hero { display:flex; align-items:center; gap:18px; padding:22px; margin:16px 0; border-radius:16px; background:#f3f6ff; }
.game-result-hero > span { font-size:3rem; }
.game-profile-summary { display:grid; gap:3px; padding:12px; border-radius:10px; background:#f4f6fb; }
.logic-expression { margin:18px auto; width:max-content; max-width:100%; padding:15px 22px; border-radius:12px; background:#172037; color:#fff; font-family:Consolas,monospace; font-size:1.3rem; font-weight:800; }
.logic-judges { display:flex; flex-wrap:wrap; justify-content:center; gap:14px; margin:20px 0; }
.logic-judge { min-width:130px; padding:18px; border-radius:50% 50% 16px 16px; text-align:center; border:3px solid; }
.logic-judge span,.logic-judge strong { display:block; }
.judge-true { background:#e5f7e9; border-color:#2b8b57; color:#145a34; }
.judge-false { background:#fde8e8; border-color:#c33c3c; color:#7d1f1f; }
.logic-choice-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:15px; max-width:650px; margin:18px auto; }
.logic-true-button { background:#27834d; }
.logic-false-button { background:#b53232; }
.logic-choice-grid button.selected { outline:5px solid #f1c40f; outline-offset:2px; }
.logic-env { display:flex; justify-content:center; flex-wrap:wrap; gap:8px; }
.logic-env span { padding:7px 11px; border-radius:999px; background:#edf0f8; font-weight:700; }
.logic-prompt { max-width:800px; margin:18px auto; font-size:1.12rem; }
.logic-option-list { max-width:850px; margin:0 auto; }
.truth-table-wrap { overflow:auto; }
.truth-table { max-width:720px; margin:16px auto; }
.truth-table th,.truth-table td { text-align:center; }
.truth-table tr.truth-correct { background:#e5f7e9; }
.truth-table tr.truth-incorrect { background:#fde8e8; }
@media (max-width:900px) { .game-menu-grid,.debug-stage-grid { grid-template-columns:1fr; } .games-lab-card { align-items:flex-start; flex-direction:column; } .logic-choice-grid { grid-template-columns:1fr; } }


/* v5.1.3 — corrected shark chase and original game-over animation */
#debugFish.fish-escaping {
  transition: left .85s ease-in, top .25s ease-out;
}

.game-over-overlay {
  position: fixed;
  inset: 0;
  z-index: 5000;
  display: grid;
  place-items: center;
  padding: 20px;
  background: rgba(7, 13, 28, .88);
}

.game-over-overlay.hidden {
  display: none;
}

.game-over-card {
  width: min(560px, 94vw);
  padding: 22px;
  border-radius: 18px;
  background: #080b12;
  color: #fff;
  text-align: center;
  box-shadow: 0 24px 70px rgba(0, 0, 0, .55);
}

.game-over-card h2 {
  margin-top: 0;
  color: #fff;
}

.game-over-card img {
  display: block;
  width: min(480px, 100%);
  height: auto;
  margin: 0 auto 14px;
  border-radius: 12px;
  background: #000;
}

.game-over-card button {
  margin-top: 8px;
}

@media (prefers-reduced-motion: reduce) {
  .debug-ocean img,
  #debugFish.fish-escaping {
    transition: none;
  }
}


/* v5.1.4 — game-over playback diagnostic */
.game-over-load-error {
  min-height: 180px;
  display: grid;
  place-items: center;
  padding: 24px;
  border: 2px dashed #f6b5b5;
  border-radius: 12px;
  background: #2a1010;
  color: #fff;
}


/* v5.1.5 — reliable MP4 shark ending with GIF fallback */
.game-over-media {
  width: min(480px, 100%);
  min-height: 260px;
  margin: 0 auto 14px;
  display: grid;
  place-items: center;
  overflow: hidden;
  border-radius: 12px;
  background: #000;
}

.game-over-media video,
.game-over-media img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 420px;
  margin: 0;
  border-radius: 0;
  object-fit: contain;
  background: #000;
}

.game-over-media video.hidden,
.game-over-media img.hidden {
  display: none;
}

#playDebugGameOverButton {
  margin-right: 8px;
}


/* v6.0 — Database Design and Development pathway */
.ddd-resource-image {
  display: block;
  width: min(920px, 100%);
  height: auto;
  margin: 18px auto;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: #fff;
}

.ddd-mini-table {
  display: grid;
  grid-template-columns: 1.4fr repeat(3, 1fr);
  gap: 1px;
  margin: 16px 0;
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--border);
}

.ddd-mini-table > div {
  padding: 12px;
  background: #fff;
}

.ddd-table {
  width: 100%;
  margin: 16px 0;
  border-collapse: collapse;
  background: #fff;
}

.ddd-table th,
.ddd-table td {
  padding: 10px;
  border: 1px solid var(--border);
  text-align: left;
}

.erd-demo {
  display: grid;
  grid-template-columns: minmax(180px, 1fr) minmax(130px, .7fr) minmax(180px, 1fr);
  gap: 18px;
  align-items: center;
  margin: 22px 0;
}

.erd-demo.large {
  margin-block: 28px;
}

.erd-entity {
  display: grid;
  gap: 0;
  overflow: hidden;
  border: 2px solid #5366d8;
  border-radius: 14px;
  background: #fff;
}

.erd-entity strong {
  padding: 12px;
  background: #eef1ff;
  font-size: 1.05rem;
}

.erd-entity span {
  padding: 9px 12px;
  border-top: 1px solid var(--border);
}

.erd-link {
  display: grid;
  gap: 8px;
  text-align: center;
}

.erd-link span {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 1.35rem;
  color: #4053cc;
}

.key-link-example {
  display: flex;
  gap: 14px;
  align-items: center;
  justify-content: center;
  margin: 15px 0;
  padding: 14px;
  border: 1px solid #acd4b9;
  border-radius: 12px;
  background: #eefaf1;
  text-align: center;
}

.key-link-example.invalid {
  border-color: #efb2b2;
  background: #fff1f1;
}

.sql-code,
.sql-editor,
.sql-error-box {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

.sql-task-introduction {
  margin-bottom: 18px;
}

.sql-database-preview {
  display: grid;
  gap: 18px;
  margin-top: 20px;
}

.sql-workspace {
  margin-top: 14px;
  padding: 20px;
  border: 1px solid #cbd4ee;
  border-radius: 16px;
  background: #f7f8ff;
}

.sql-workspace-heading {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 14px;
}

.sql-workspace-heading h3 {
  margin: 3px 0 0;
}

.sql-editor {
  width: 100%;
  min-height: 210px;
  margin-top: 8px;
  padding: 16px;
  resize: vertical;
  border: 2px solid #b9c2de;
  border-radius: 12px;
  background: #121827;
  color: #f8fafc;
  font-size: 1rem;
  line-height: 1.55;
  tab-size: 2;
}

.sql-editor:focus {
  border-color: #5268ed;
  outline: 3px solid rgba(82, 104, 237, .15);
}

.sql-output-panel {
  margin-top: 18px;
}

.sql-result-block {
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: #fff;
}

.sql-result-block .subsection-heading {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  background: #f3f5fb;
}

.sql-result-table {
  min-width: 100%;
}

.sql-result-table th {
  white-space: nowrap;
  background: #e9edfb;
}

.sql-result-table td,
.sql-result-table th {
  padding: 9px 11px;
  border: 1px solid #d9deeb;
}

.sql-empty-result {
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
}

.sql-error-box {
  margin: 0;
  padding: 16px;
  overflow-x: auto;
  white-space: pre-wrap;
  border: 1px solid #e2a9a9;
  border-radius: 12px;
  background: #fff0f0;
  color: #771b1b;
}

@media (max-width: 760px) {
  .erd-demo {
    grid-template-columns: 1fr;
  }

  .erd-link span {
    transform: rotate(90deg);
  }

  .ddd-mini-table {
    grid-template-columns: 1fr;
  }

  .sql-workspace-heading {
    display: grid;
  }
}


/* v7.0 — current edit preview, ERD drawing and Computer Systems */
.variable-box-demo { max-width:360px; margin:16px auto; border:3px solid #5a66d6; border-radius:14px; background:#f4f5ff; overflow:hidden; text-align:center; }
.variable-label { padding:8px; background:#525fc8; color:white; font-weight:800; }
.variable-value { padding:22px; font:700 1.15rem Consolas, monospace; }
.binary-place-strip,.binary-place-values,.binary-bits { display:grid; grid-template-columns:repeat(8,minmax(38px,1fr)); gap:7px; max-width:760px; margin:10px auto; text-align:center; }
.binary-place-strip span,.binary-place-values span { padding:8px 2px; border-radius:8px; background:#edf0f8; font-weight:800; }
.binary-bits button { min-height:54px; border:2px solid #8c96ac; border-radius:10px; background:white; color:#1a2540; font:800 1.35rem Consolas,monospace; }
.binary-bits button.on { background:#4457db; color:white; border-color:#3344b7; }
.binary-bits button:disabled { opacity:1; cursor:default; }
.binary-total { margin:14px 0; text-align:center; font-size:1.08rem; }
.binary-builder > label { display:block; max-width:320px; margin:14px auto; }
.binary-builder input { width:100%; margin-top:5px; padding:10px; }
.vector-demo,.memory-bus-demo { display:flex; flex-wrap:wrap; align-items:center; justify-content:center; gap:24px; margin:16px 0; padding:16px; border:1px solid #ccd3e4; border-radius:14px; background:#f8f9fc; }
.vector-shape { width:150px; height:90px; background:#a7d5ff; border:5px solid #355b97; }
.pixel-grid { display:grid; grid-template-columns:repeat(8,24px); gap:2px; width:max-content; margin:16px auto; padding:8px; background:#dce2ec; }
.pixel-grid span { width:24px; height:24px; background:white; }
.pixel-grid span.on { background:#344fc2; }
.architecture-diagram { display:flex; justify-content:center; margin:18px 0; }
.arch-box { width:min(440px,100%); padding:18px; border:3px solid #4655be; border-radius:16px; text-align:center; background:#f1f3ff; }
.arch-box > div { margin:9px; padding:10px; border:1px solid #8993c8; border-radius:8px; background:white; }
.memory-stack { display:grid; gap:5px; }
.memory-stack span { padding:8px 14px; border:1px solid #8792aa; background:white; }
.bus-lines { display:grid; gap:18px; min-width:260px; }
.bus-lines strong { padding:10px; border-block:3px solid #4f5dc8; }
.erd-builder-shell { display:grid; gap:14px; }
.erd-mode-toggle { display:flex; gap:8px; flex-wrap:wrap; }
.erd-mode-toggle button { background:#e8ecf6; color:#1f2941; }
.erd-mode-toggle button.active { background:#4d5fd3; color:white; }
.erd-layout { display:grid; grid-template-columns:minmax(320px,440px) 1fr; gap:16px; align-items:start; }
.erd-editor-panel,.erd-canvas { border:1px solid #ccd3e2; border-radius:14px; background:white; padding:14px; }
.erd-canvas { min-height:520px; overflow:auto; background-image:linear-gradient(#edf0f7 1px,transparent 1px),linear-gradient(90deg,#edf0f7 1px,transparent 1px); background-size:24px 24px; }
.erd-entity-editor { padding:12px; margin-bottom:12px; border:1px solid #c9d0df; border-radius:12px; background:#f8f9fc; }
.erd-editor-heading { display:flex; justify-content:space-between; align-items:center; margin-bottom:8px; }
.erd-entity-editor label { display:block; margin:8px 0; font-weight:700; }
.erd-entity-editor input,.erd-entity-editor select,.erd-relationship-words input { width:100%; margin-top:4px; padding:8px; border:1px solid #bfc8da; border-radius:8px; }
.erd-attribute-head,.erd-attribute-edit { display:grid; grid-template-columns:1fr 76px 38px; gap:6px; align-items:center; }
.erd-attribute-head { font-size:.78rem; color:#667087; font-weight:800; }
.erd-attribute-edit { margin:6px 0; }
.erd-attribute-edit button,.danger-small { padding:6px; background:#f6dddd; color:#8b2b2b; }
.compact-button { padding:7px 10px; }
.erd-relationship-words { display:grid; grid-template-columns:1fr 1fr; gap:12px; }
.erd-table-diagram { min-height:460px; display:flex; align-items:center; justify-content:center; gap:16px; }
.erd-table-box { width:230px; border:3px solid #536078; border-radius:12px; overflow:hidden; background:white; box-shadow:0 8px 20px rgba(30,40,70,.12); }
.erd-table-box.one { border-color:#3564c2; }.erd-table-box.many { border-color:#8145a8; }
.erd-table-box h4 { margin:0; padding:12px; background:#263450; color:white; text-align:center; }
.erd-table-box > div { display:flex; justify-content:space-between; padding:8px 10px; border-top:1px solid #d9deea; }
.erd-link { display:grid; grid-template-columns:auto 38px auto 38px auto; align-items:center; gap:5px; font-weight:800; }
.erd-link i { height:3px; background:#4f596f; }.erd-link strong { font-size:.8rem; max-width:90px; text-align:center; }
.erd-canvas svg { width:100%; min-width:720px; height:auto; min-height:500px; }
.erd-svg-link,.erd-attribute-line { stroke:#566079; stroke-width:3; }.erd-attribute-line { stroke-width:2; }
.erd-entity-rect { fill:#293650; stroke:#111b30; stroke-width:3; }.erd-entity-rect.one { fill:#315fbd; }.erd-entity-rect.many { fill:#7b41a6; }
.erd-entity-text { fill:white; font-size:18px; font-weight:800; }
.erd-attribute-bubble { fill:white; stroke:#65718b; stroke-width:2; }.erd-attribute-text { font-size:13px; fill:#1b263c; }.erd-cardinality { font-size:22px; font-weight:900; fill:#293650; }.erd-verb { font-size:13px; font-weight:700; fill:#293650; }.erd-pk-underline { stroke:#1b263c; stroke-width:2; }.erd-symbol-note { text-align:center; color:#5d667b; }
@media (max-width:980px){.erd-layout{grid-template-columns:1fr}.erd-table-diagram{flex-direction:column}.erd-link{transform:rotate(90deg);margin:22px}.erd-relationship-words{grid-template-columns:1fr}}
@media (max-width:700px){.binary-place-strip,.binary-place-values,.binary-bits{gap:3px}.binary-place-strip span,.binary-place-values span{font-size:.72rem}.binary-bits button{min-height:44px;padding:4px}.erd-canvas{padding:6px}}


/* v7.0.1 — six-attempt fluency, hidden conversion answers and cleaner ERDs */
.fluency-counter { display:inline-block; margin:0 0 10px; padding:6px 10px; border-radius:999px; background:#eef1ff; color:#3345ad; }
.binary-row-heading,.binary-grouped-row { display:grid; grid-template-columns:1fr 1fr; gap:24px; max-width:820px; margin:8px auto; }
.binary-row-heading span { text-align:center; font-weight:800; color:#5f687d; text-transform:uppercase; letter-spacing:.04em; font-size:.78rem; }
.binary-nibble { display:grid; grid-template-columns:repeat(4,minmax(50px,1fr)); gap:7px; }
.binary-place-entry-row input,.binary-contribution-row input { width:100%; min-width:0; padding:11px 4px; border:2px solid #aab3c8; border-radius:10px; text-align:center; font:800 1.02rem Consolas,monospace; background:white; }
.binary-place-entry-row input:focus,.binary-contribution-row input:focus { border-color:#4d62e6; outline:3px solid rgba(77,98,230,.18); }
.binary-step-label { max-width:820px; margin:18px auto 6px; }
.centered { text-align:center; }
.binary-calculator { max-width:820px; margin:18px auto; padding:14px; display:grid; grid-template-columns:1fr auto 90px; gap:12px; align-items:center; border:1px solid #cad2e3; border-radius:14px; background:#f7f9fd; }
.binary-calculator p { margin:4px 0 0; font-family:Consolas,monospace; overflow-wrap:anywhere; }
.binary-calculator output { min-height:48px; display:grid; place-items:center; border:2px solid #5967d2; border-radius:10px; background:white; font:900 1.25rem Consolas,monospace; }
.binary-final-answer { display:block; max-width:420px!important; margin:18px auto!important; font-weight:800; }
.binary-final-answer input { font:800 1.1rem Consolas,monospace; }
.pattern-card { max-width:820px; margin:12px auto; padding:10px 12px; border:1px solid #d4dae8; border-radius:10px; background:#fffdf3; }
.binary-place-strip span:nth-child(5) { margin-left:18px; }
.erd-relationship-diamond { fill:#fff4cc; stroke:#7d6732; stroke-width:3; }
.erd-relationship-text { fill:#2b2f3a; font-size:13px; font-weight:800; }
.erd-canvas svg { min-width:820px; }
.erd-attribute-bubble { fill:#fff; stroke:#65718b; stroke-width:2.5; }
.erd-symbol-note { max-width:760px; margin:6px auto 0; }
@media (max-width:700px) {
  .binary-row-heading,.binary-grouped-row { gap:12px; }
  .binary-nibble { gap:3px; grid-template-columns:repeat(4,minmax(34px,1fr)); }
  .binary-place-entry-row input,.binary-contribution-row input { padding:8px 2px; font-size:.82rem; }
  .binary-calculator { grid-template-columns:1fr; }
  .binary-calculator output { min-height:42px; }
}


/* v7.0.2 — keyboard flow and consistent next-question navigation */
.binary-place-entry-row input.entry-correct,
.binary-contribution-row input.entry-correct {
  border-color: #25835b;
  background: #eefaf5;
  box-shadow: inset 0 0 0 1px rgba(37, 131, 91, .18);
}

.next-question-actions {
  display: flex;
  justify-content: flex-end;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid rgba(45, 62, 96, .18);
}

.next-question-button {
  min-width: 180px;
  background: #243fc5;
  color: #fff;
  box-shadow: 0 6px 15px rgba(36, 63, 197, .2);
}

.next-question-button:hover:not(:disabled) {
  background: #1933b5;
}

.next-question-button:focus-visible {
  outline: 4px solid rgba(36, 63, 197, .25);
  outline-offset: 3px;
}

@media (max-width: 620px) {
  .next-question-actions { justify-content: stretch; }
  .next-question-button { width: 100%; }
}


/* v8.0 — Revision Hub and six-attempt fluency */
.revision-hub-card { display:flex; justify-content:space-between; gap:24px; align-items:center; border-left:7px solid #7b41a6; }
.revision-session-card { max-width:1180px; margin:18px auto; }
.revision-setup-grid { display:grid; grid-template-columns:repeat(3,minmax(0,1fr)); gap:14px; }
.revision-setup-summary { padding:12px 14px; border-radius:10px; background:#f0f2fb; }
.revision-topic-grid { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:9px; margin-bottom:16px; }
.revision-topic-choice { display:flex; gap:9px; align-items:flex-start; padding:10px 12px; border:1px solid #d6dceb; border-radius:10px; background:#fff; }
.revision-prompt { margin:20px 0; font-size:1.35rem; }
.revision-answer { min-height:150px; }
.revision-compare-grid { display:grid; grid-template-columns:1fr 1fr; gap:16px; margin-top:18px; }
.revision-compare-grid section { min-width:0; }
.revision-answer-panel { min-height:160px; margin:0; padding:16px; white-space:pre-wrap; overflow-wrap:anywhere; border:1px solid #d7ddeb; border-radius:12px; background:#f8f9fd; font:inherit; }
.revision-answer-panel.accepted { background:#eef8f3; border-color:#b7dbc9; }
.revision-mark-points { grid-column:1/-1; padding:14px; border-radius:12px; background:#fff9e8; border:1px solid #ead9a4; }
.revision-point { display:flex; gap:9px; padding:6px 0; }
.revision-rating-buttons { margin-top:18px; display:flex; flex-wrap:wrap; gap:10px; align-items:center; }
.revision-rating-buttons p { flex-basis:100%; margin:0; }
.revision-summary-hero { padding:18px; border-radius:14px; background:#eef1ff; }
.fluency-shell { padding:18px; border:1px solid #d6dceb; border-radius:14px; background:#fff; }
.fluency-progress-strip { display:grid; grid-template-columns:repeat(6,1fr); gap:8px; margin:14px 0 22px; }
.fluency-progress-strip span { display:grid; place-items:center; min-height:38px; border-radius:999px; background:#edf0f7; font-weight:800; }
.fluency-progress-strip span.current { outline:3px solid #5a67e8; background:#eef0ff; }
.fluency-progress-strip span.complete { background:#dff3e9; color:#1f6c4e; }
.fluency-editor { min-height:180px; font-family:ui-monospace,SFMono-Regular,Consolas,monospace; }
.compact-response { min-height:110px; }
button.good { background:#237b57; color:#fff; }
@media (max-width:760px){.revision-hub-card{align-items:stretch;flex-direction:column}.revision-setup-grid,.revision-topic-grid,.revision-compare-grid{grid-template-columns:1fr}.revision-rating-buttons button{flex:1}.fluency-progress-strip{gap:4px}}

/* v8.0.1 revision navigation */
.revision-next-actions { margin-top: 16px; justify-content: flex-end; }
.revision-next-actions button { min-width: 210px; font-size: 1.05rem; }
.revision-rating-buttons button.selected-rating { outline: 4px solid rgba(59, 91, 219, .28); outline-offset: 2px; transform: translateY(-1px); }


/* v8.1: IDLE-style Python editor and integrated SDD fluency workspace */
.code-editor-shell {
  position: relative;
  width: 100%;
  border: 2px solid var(--border);
  border-radius: 10px;
  background: #fff;
  overflow: hidden;
}
.code-editor-shell:focus-within {
  outline: 3px solid rgba(56, 103, 232, .18);
  border-color: var(--blue);
}
.code-editor-shell .code-highlight,
.code-editor-shell .smart-code-input {
  margin: 0;
  padding: 15px;
  width: 100%;
  min-height: 290px;
  border: 0;
  border-radius: 0;
  font-family: Consolas, "Courier New", monospace;
  font-size: 16px;
  line-height: 1.5;
  tab-size: 4;
  white-space: pre;
  overflow: auto;
}
.code-editor-shell .code-highlight {
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  color: #000;
  background: #fff;
}
.code-editor-shell .smart-code-input {
  position: relative;
  z-index: 2;
  display: block;
  resize: vertical;
  background: transparent;
  color: #111;
  caret-color: #111;
  outline: 0;
}
.code-editor-shell.syntax-ready .smart-code-input {
  color: transparent;
  -webkit-text-fill-color: transparent;
}
.code-editor-shell.syntax-ready .smart-code-input::selection {
  background: rgba(48, 112, 210, .28);
  color: transparent;
  -webkit-text-fill-color: transparent;
}
.idle-keyword { color: #ff7700; font-weight: 700; }
.idle-builtin { color: #900090; }
.idle-string { color: #00a000; }
.idle-comment { color: #dd0000; font-style: italic; }
.idle-number { color: #0000cc; }
.editor-keyboard-help,
.editor-help-line {
  color: var(--muted);
  font-size: .92rem;
}
.editor-keyboard-help { margin: 8px 2px 0; }
.fluency-challenge-prompt { font-size: 1.08rem; margin: 16px 0 6px; }
.challenge-card .fluency-progress-strip { margin: 4px 0 14px; }
.fluency-progress-strip span.current { outline: 3px solid rgba(56,103,232,.22); }
.fluency-progress-strip span.complete { background: var(--green); color: white; border-color: var(--green); }
.fluency-editor.code-editor-shell, .fluency-shell .code-editor-shell { margin-top: 8px; }
@media (max-width: 720px) {
  .code-editor-shell .code-highlight,
  .code-editor-shell .smart-code-input { font-size: 14px; padding: 12px; }
}

.activity-row.fluency-row {
  border-left: 5px solid var(--purple);
  background: #fbf9ff;
}
.activity-chip.fluency-chip {
  background: #eee8ff;
  color: #4d2ea1;
}

/* Nat 5 Computing v8.2: individual licences and learning routes */
.licence-status-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}
.licence-status-card h3,
.licence-status-card p { margin-top: 0; }
.licence-status-card p:last-child { margin-bottom: 0; }
.learning-route-section { margin: 1rem 0 1.25rem; }
.learning-route-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}
.learning-route-card {
  display: flex;
  align-items: center;
  gap: .9rem;
  width: 100%;
  padding: 1rem;
  text-align: left;
  border: 2px solid var(--border, #d8dee8);
  border-radius: 16px;
  background: var(--surface, #fff);
  color: inherit;
  box-shadow: none;
}
.learning-route-card:hover { transform: translateY(-1px); }
.learning-route-card.active {
  border-color: var(--primary, #2356c4);
  box-shadow: 0 0 0 3px rgba(35, 86, 196, .12);
}
.learning-route-card strong,
.learning-route-card small { display: block; }
.learning-route-card small { margin-top: .25rem; line-height: 1.4; opacity: .78; }
.route-icon { font-size: 1.8rem; }
.route-notice {
  margin-top: .8rem;
  padding: .8rem 1rem;
  border-radius: 12px;
  background: rgba(35, 86, 196, .07);
  line-height: 1.5;
}
.route-notice.accelerator { background: rgba(230, 126, 34, .10); }
.accelerator-method-panel {
  margin-top: .9rem;
  padding: 1rem;
  border: 1px solid #f0c99d;
  border-radius: 14px;
  background: #fffaf4;
}
.accelerator-method-heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: .8rem;
}
.accelerator-method-heading h4,
.accelerator-method-heading p { margin-top: 0; }
.accelerator-method-heading h4 { margin-bottom: 0; }
.accelerator-method-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: .7rem;
}
.accelerator-method-grid > div {
  display: grid;
  gap: .25rem;
  padding: .75rem;
  border: 1px solid #f1d9bd;
  border-radius: 11px;
  background: white;
}
.accelerator-method-grid span {
  color: var(--muted);
  font-size: .9rem;
  line-height: 1.35;
}
.accelerator-route .unit-card { border-left: 4px solid #e67e22; }
.accelerator-route .activity-row:not(.locked) .activity-chip:first-child::after {
  content: " · Accelerator";
}
@media (max-width: 760px) {
  .learning-route-grid,
  .accelerator-method-grid { grid-template-columns: 1fr; }
  .licence-status-card,
  .accelerator-method-heading { align-items: flex-start; flex-direction: column; }
}


/* v8.2.2: practical accelerator laboratories */
.accelerator-practical-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 16px;
}
.accelerator-practical-card {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface, #fff);
}
.accelerator-practical-card .route-icon {
  flex: 0 0 auto;
  font-size: 1.45rem;
}
.accelerator-practical-card strong,
.accelerator-practical-card span {
  display: block;
}
.accelerator-practical-card div > span {
  margin-top: 5px;
  color: var(--muted);
  line-height: 1.45;
}
@media (max-width: 760px) {
  .accelerator-practical-grid { grid-template-columns: 1fr; }
}

/* v8.3.0 — Daily Mastery */
.learning-route-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.mastery-route-card { border-style: solid; }
.mastery-dashboard-heading { align-items: flex-start; }
.mastery-level-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin: 1rem 0;
}
.mastery-level-card {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}
.mastery-level-card h3 { margin: .1rem 0 .2rem; font-size: 2rem; }
.mastery-level-card p { margin-top: .2rem; }
.mastery-level-icon { font-size: 2rem; line-height: 1; }
.mastery-diagnostic-card,
.daily-plan-card { margin-top: 1rem; }
.mastery-diagnostic-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 1rem;
  align-items: center;
}
.diagnostic-button-row { display: flex; gap: .6rem; flex-wrap: wrap; justify-content: flex-end; }
.daily-mastery-mix {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: .75rem;
  margin: 1rem 0;
}
.daily-mastery-mix > div {
  display: grid;
  grid-template-columns: auto 1fr;
  column-gap: .6rem;
  align-items: center;
  padding: .8rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface, #fff);
}
.daily-mastery-mix > div span { grid-row: span 2; font-size: 1.5rem; }
.daily-mastery-mix > div strong { font-size: 1.3rem; }
.daily-mastery-mix > div small { color: var(--muted); }
.daily-mastery-recommendation {
  display: grid;
  gap: .25rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  margin-bottom: 1rem;
}
.daily-mastery-recommendation .activity-chip { width: max-content; }
.daily-mastery-recommendation small { color: var(--muted); }
.mastery-next-step,
.diagnostic-result {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  margin: 1rem 0;
}
.diagnostic-result { display: flex; gap: 1rem; align-items: flex-start; }
.diagnostic-result h2 { margin: .1rem 0; font-size: 2.3rem; }
.diagnostic-result h3 { margin-top: .2rem; }
.mastery-map-v83 .level-column { min-width: 70px; }
.mastery-level-cell {
  font-weight: 800;
  white-space: nowrap;
  border-radius: 8px !important;
  background: #f5f7fa !important;
  padding: .45rem !important;
}
.mastery-level-cell.has-repair { background: #fff1f0 !important; }
.activity-row .retained { font-weight: 800; }

@media (max-width: 900px) {
  .learning-route-grid,
  .mastery-level-grid { grid-template-columns: 1fr; }
  .mastery-diagnostic-card { grid-template-columns: 1fr; }
  .diagnostic-button-row { justify-content: flex-start; }
  .daily-mastery-mix { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 520px) {
  .daily-mastery-mix { grid-template-columns: 1fr; }
}

/* v8.3.2 pupil identity / profile actions */
.profile-heading-actions { margin-top: 0; justify-content: flex-end; }
.pupil-row-actions { display: flex; gap: 7px; flex-wrap: wrap; }
@media (max-width: 620px) {
  .profile-heading-actions { width: 100%; justify-content: flex-start; }
}

/* =========================================================
   v8.4 Computing Arcade
   ========================================================= */
.class-arcade-panel {
  display: grid;
  grid-template-columns: minmax(0,1fr) auto;
  gap: 22px;
  align-items: center;
  margin: 18px 0;
  padding: 18px;
  border: 1px solid #cfd8ff;
  border-radius: 16px;
  background: linear-gradient(135deg, #f7f5ff, #eef8ff);
}
.class-arcade-heading { display:flex; gap:12px; align-items:center; }
.class-arcade-heading h4 { margin:0; }
.class-arcade-heading .eyebrow { margin:0 0 3px; }
.arcade-big-icon { font-size:2rem; }
.class-arcade-actions { display:grid; gap:8px; justify-items:end; min-width:170px; }
.class-arcade-actions .help-text { min-height:1.2em; text-align:right; }
.arcade-closed-card { opacity:.82; background:#f3f4f7; }
.arcade-heading { align-items:center; }
.arcade-marquee {
  display:inline-flex;
  align-items:center;
  justify-content:center;
  min-height:54px;
  padding:0 18px;
  border-radius:14px;
  background:#172033;
  color:#fff;
  font-weight:900;
  letter-spacing:.09em;
  box-shadow: inset 0 0 0 2px rgba(255,255,255,.13), 0 8px 20px rgba(23,32,51,.16);
}
.arcade-scope-card {
  display:grid;
  grid-template-columns:minmax(0,1fr) auto;
  gap:18px;
  align-items:center;
  background:linear-gradient(135deg,#fffaf0,#f5f3ff);
}
.arcade-mode-switch { display:flex; gap:10px; flex-wrap:wrap; justify-content:flex-end; }
.arcade-mode-button.active { background:var(--purple); color:#fff; }
.arcade-practice-note { grid-column:1 / -1; margin:0; font-size:.92rem; color:var(--muted); }
.arcade-cabinet-grid { grid-template-columns:repeat(3,minmax(0,1fr)); }
.arcade-cabinet {
  position:relative;
  overflow:hidden;
  min-height:255px;
  border-width:2px;
  box-shadow:0 10px 24px rgba(27,38,61,.09);
}
.arcade-cabinet::after {
  content:"";
  position:absolute;
  inset:auto -30px -45px auto;
  width:120px;
  height:120px;
  border-radius:50%;
  background:rgba(255,255,255,.45);
  pointer-events:none;
}
.arcade-cabinet .game-icon { font-size:2.4rem; filter:drop-shadow(0 4px 8px rgba(0,0,0,.08)); }
.flyer-cabinet { background:linear-gradient(145deg,#eefaff,#f7ffed); border-color:#b7dfea; }
.race-cabinet { background:linear-gradient(145deg,#fff7e8,#fff); border-color:#efd4a4; }
.bomb-cabinet { background:linear-gradient(145deg,#fff0f0,#fff9e9); border-color:#edbbbb; }
.sql-cabinet { background:linear-gradient(145deg,#f0f4ff,#f7f1ff); border-color:#c9cef3; }
.cyber-cabinet { background:linear-gradient(145deg,#eefdf7,#eff7ff); border-color:#b9dfd1; }

.quick-arcade-shell {
  margin-top:18px;
  border:2px solid #d6dce6;
  overflow:hidden;
}
.quick-arcade-hud {
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:10px;
  margin:12px 0 10px;
}
.quick-arcade-hud span {
  padding:10px 12px;
  border-radius:10px;
  background:#172033;
  color:#fff;
  text-align:center;
  font-weight:800;
}
.arcade-track {
  height:12px;
  border-radius:999px;
  background:#e7ebf1;
  overflow:hidden;
  margin-bottom:20px;
}
.arcade-track-fill {
  width:0;
  height:100%;
  border-radius:inherit;
  background:linear-gradient(90deg,#2b9850,#e5b12a,#d54b45);
  transition:width .3s ease;
}
.arcade-screen {
  min-height:330px;
  padding:24px;
  border-radius:18px;
  background:#f8fafc;
  border:1px solid #dde3ec;
  position:relative;
}
.arcade-screen h3 { font-size:1.25rem; line-height:1.45; max-width:900px; margin:0 auto 20px; text-align:center; }
.arcade-question-media { max-width:900px; margin:0 auto 18px; }
.arcade-code { max-height:260px; overflow:auto; }
.arcade-answer-grid {
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:14px;
  max-width:900px;
  margin:0 auto;
}
.arcade-answer {
  min-height:76px;
  display:flex;
  gap:12px;
  align-items:center;
  text-align:left;
  background:#fff;
  color:var(--navy);
  border:2px solid #cfd7e5;
  box-shadow:0 5px 12px rgba(27,38,61,.05);
}
.arcade-answer:hover:not(:disabled) { border-color:var(--blue); filter:none; transform:translateY(-1px); }
.arcade-answer.selected { border-color:var(--purple); box-shadow:0 0 0 3px rgba(109,70,200,.14); }
.arcade-answer.correct { border-color:#43a861; background:#effaf2; }
.arcade-answer.incorrect { border-color:#cf5454; background:#fff1f1; }
.arcade-answer-key {
  display:inline-grid;
  place-items:center;
  width:34px;
  height:34px;
  border-radius:50%;
  flex:0 0 34px;
  background:#edf1f7;
  font-weight:900;
}
.quick-arcade-shell[data-arcade-theme="flyer"] .arcade-screen { background:linear-gradient(#eaf8ff 0 68%,#e9f8df 68% 100%); }
.quick-arcade-shell[data-arcade-theme="race"] .arcade-screen { background:linear-gradient(180deg,#fffaf0,#f5f6f8); }
.quick-arcade-shell[data-arcade-theme="bomb"] .arcade-screen { background:linear-gradient(145deg,#2a2a31,#15161a); color:#fff; }
.quick-arcade-shell[data-arcade-theme="bomb"] .arcade-answer { background:#262832; color:#fff; border-color:#555b6b; }
.quick-arcade-shell[data-arcade-theme="bomb"] .arcade-answer-key { background:#444957; }
.quick-arcade-shell[data-arcade-theme="sql"] .arcade-screen { background:#f2f5ff; }
.quick-arcade-shell[data-arcade-theme="cyber"] .arcade-screen { background:linear-gradient(145deg,#effcf7,#eef6ff); }

@media (max-width: 980px) {
  .arcade-cabinet-grid { grid-template-columns:repeat(2,minmax(0,1fr)); }
}
@media (max-width: 720px) {
  .class-arcade-panel, .arcade-scope-card { grid-template-columns:1fr; }
  .class-arcade-actions { justify-items:start; }
  .class-arcade-actions .help-text { text-align:left; }
  .arcade-mode-switch { justify-content:flex-start; }
  .arcade-cabinet-grid, .arcade-answer-grid { grid-template-columns:1fr; }
  .quick-arcade-hud { grid-template-columns:1fr 1fr 1fr; font-size:.86rem; }
}