:root{--brand: #1E56E0;--brand-hover: #1848C5;--brand-press: #133AA3;--brand-soft: #E5EDFD;--brand-fg: #FFFFFF;--accent-teal: #0EA5A7;--accent-teal-soft: #D6F3F4;--gold: #D4A017;--gold-soft: #FBF0D2;--surface-0: #F6F8FB;--surface-1: #FFFFFF;--surface-2: #F2F5F9;--surface-3: #E8EDF4;--fg-1: #0B1220;--fg-2: #2B3648;--fg-3: #5A667A;--fg-4: #94A0B3;--stroke-1: #E2E7F0;--stroke-2: #CBD3E0;--elev-1: 0 1px 0 rgba(11,18,32,.04);--elev-2: 0 1px 2px rgba(11,18,32,.06), 0 1px 0 rgba(11,18,32,.04);--elev-3: 0 6px 20px -4px rgba(11,18,32,.1), 0 2px 4px rgba(11,18,32,.05);--elev-4: 0 20px 40px -8px rgba(11,18,32,.18), 0 4px 12px rgba(11,18,32,.08);--accent: var(--brand);--accent-soft: var(--brand-soft);--amber: var(--accent-teal);--amber-soft: var(--accent-teal-soft);--panel: rgba(255, 255, 255, .9);--border: var(--stroke-1);--border-strong: var(--stroke-2);--text: var(--fg-1);--text-dim: var(--fg-3);--text-faint: var(--fg-4);--fs: 1}@media (min-width: 2000px){:root{--fs: 1.12}}@media (min-width: 2560px){:root{--fs: 1.24}}@media (min-width: 3200px){:root{--fs: 1.38}}*{box-sizing:border-box}html,body,#root{height:100%;margin:0}body{font-family:IBM Plex Sans Arabic,system-ui,sans-serif;background:var(--surface-0);color:var(--text);overflow:hidden;-webkit-font-smoothing:antialiased}button{font-family:inherit;color:inherit;cursor:pointer}.app{position:fixed;top:0;right:0;bottom:0;left:0}canvas{display:block}.splash{position:fixed;top:0;right:0;bottom:0;left:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:16px;background:var(--surface-0)}.spinner{width:46px;height:46px;border-radius:50%;border:3px solid var(--surface-3);border-top-color:var(--brand);animation:spin 1s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.splash .b{font-size:20px;font-weight:700;color:var(--fg-1)}.splash .t{font-size:14px;color:var(--text-dim)}.topbar{position:absolute;top:0;inset-inline:0;height:54px;z-index:5;display:flex;align-items:center;gap:12px;padding:0 16px;background:linear-gradient(180deg,#f6f8fbf2,#f6f8fb00);border-bottom:1px solid transparent}.brand{display:flex;align-items:center;gap:10px}.brand .logo{width:32px;height:32px;border-radius:8px;display:grid;place-items:center;font-size:17px;color:#fff;background:linear-gradient(135deg,var(--brand),var(--brand-press))}.brand b{font-size:calc(14px * var(--fs));display:block;line-height:1.2;color:var(--fg-1)}.brand span{font-size:11px;color:var(--text-dim)}.lesson{margin:0 auto;font-size:calc(13px * var(--fs));color:var(--text-dim);background:var(--surface-1);border:1px solid var(--border);border-radius:20px;padding:6px 15px;box-shadow:var(--elev-1)}.lesson b{color:var(--brand-press)}.top-actions{display:flex;gap:8px}.act{display:flex;align-items:center;gap:7px;border:1px solid var(--stroke-2);background:var(--surface-1);padding:8px 12px;border-radius:9px;font-size:calc(12.5px * var(--fs));color:var(--fg-2);box-shadow:var(--elev-1)}.act:hover{border-color:var(--brand);color:var(--brand)}.act.primary{background:var(--brand);color:var(--brand-fg);border-color:transparent;font-weight:600}.act.primary:hover{background:var(--brand-hover);color:var(--brand-fg)}.act.on{background:var(--brand-soft);color:var(--brand-press);border-color:transparent}.panel{position:absolute;background:var(--panel);border:1px solid var(--border);border-radius:14px;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);box-shadow:var(--elev-3);z-index:5}.panel h3{margin:0;padding:13px 15px 9px;font-size:calc(13px * var(--fs));font-weight:600;color:var(--fg-1);display:flex;align-items:center;gap:8px}.panel h3 .sub{margin-inline-start:auto;font-size:10.5px;color:var(--text-faint);font-weight:400}.sep{height:1px;background:var(--border);margin:2px 0}#control{top:66px;inset-inline-start:14px;width:256px;max-height:calc(100% - 150px);overflow:auto}.layer{display:flex;align-items:center;gap:11px;padding:9px 15px;font-size:calc(13px * var(--fs))}.layer .dot{width:9px;height:9px;border-radius:50%;flex:0 0 auto}.layer .nm{flex:1;color:var(--fg-1)}.layer .nm small{display:block;color:var(--text-faint);font-size:10.5px}.sw{position:relative;width:36px;height:20px;border-radius:20px;border:0;flex:0 0 auto;background:var(--stroke-2);transition:.2s}.sw:after{content:"";position:absolute;top:2px;inset-inline-end:2px;width:16px;height:16px;border-radius:50%;background:#fff;box-shadow:var(--elev-1);transition:.2s}.sw.on{background:var(--brand)}.sw.on:after{inset-inline-end:18px}.grid2{display:grid;grid-template-columns:1fr 1fr;gap:7px;padding:6px 15px 10px}.tb{display:flex;align-items:center;gap:7px;justify-content:center;border:1px solid var(--stroke-2);background:var(--surface-1);border-radius:8px;padding:9px 8px;font-size:calc(12px * var(--fs));color:var(--fg-2)}.tb:hover{border-color:var(--brand);color:var(--brand)}.tb.on{background:var(--brand-soft);color:var(--brand-press);border-color:transparent}.tool{padding:8px 15px 12px}.tool .lbl{display:flex;justify-content:space-between;font-size:calc(12.5px * var(--fs));color:var(--text-dim);margin-bottom:8px}.tool .lbl b{color:var(--accent-teal);font-weight:600}input[type=range]{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;height:4px;border-radius:4px;background:var(--surface-3);outline:none}input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;width:15px;height:15px;border-radius:50%;background:var(--accent-teal);cursor:pointer;box-shadow:0 0 0 4px var(--accent-teal-soft)}.presets{display:flex;flex-wrap:wrap;gap:7px;padding:6px 15px 14px}.preset{border:1px solid var(--stroke-2);background:var(--surface-1);border-radius:20px;padding:7px 12px;font-size:calc(12px * var(--fs));color:var(--fg-2)}.preset:hover{border-color:var(--brand);color:var(--brand);background:var(--brand-soft)}#info{top:66px;inset-inline-end:14px;width:282px}#info .closex{margin-inline-start:auto;border:0;background:transparent;color:var(--text-faint);font-size:16px}#info .closex:hover{color:var(--fg-1)}.info-photo{height:110px;margin:0 14px;border-radius:10px;border:1px solid var(--border);position:relative;overflow:hidden}.info-photo .tag{position:absolute;inset-block-end:8px;inset-inline-start:8px;background:#0b122099;color:#fff;padding:3px 9px;border-radius:6px;font-size:11px}.info-rows{padding:13px 15px;display:flex;flex-direction:column;gap:9px}.irow{display:flex;gap:10px;font-size:calc(12.5px * var(--fs))}.irow .k{color:var(--text-faint);min-width:74px}.irow .v{color:var(--fg-1);flex:1}.badge{display:inline-block;padding:2px 9px;border-radius:20px;font-size:11px;font-weight:600}.info-desc{padding:0 15px 14px;font-size:calc(12.5px * var(--fs));line-height:1.7;color:var(--text-dim)}#info .cta{margin:0 15px 15px;width:calc(100% - 30px);justify-content:center}#timebar{inset-block-end:14px;inset-inline-start:50%;transform:translate(50%);width:440px;padding:13px 16px}#timebar .top{display:flex;align-items:center;gap:10px;margin-bottom:11px}#timebar .play{width:34px;height:34px;border-radius:9px;border:0;background:var(--brand);color:var(--brand-fg);display:grid;place-items:center;font-size:14px;flex:0 0 auto}#timebar .play:hover{background:var(--brand-hover)}#timebar .step{width:30px;height:30px;border-radius:8px;border:1px solid var(--stroke-2);background:var(--surface-1);display:grid;place-items:center;color:var(--fg-2)}#timebar .step:hover{border-color:var(--brand);color:var(--brand)}#timebar .titles b{font-size:calc(13px * var(--fs));display:block;color:var(--fg-1)}#timebar .titles span{font-size:11px;color:var(--brand);font-weight:600}#timebar .read{margin-inline-start:auto;text-align:end}#timebar .read b{font-size:calc(18px * var(--fs));color:var(--accent-teal);font-weight:700}#timebar .read span{font-size:10.5px;color:var(--text-faint);display:block}#timebar .ticks{display:flex;justify-content:space-between;font-size:10px;color:var(--text-faint);margin-top:7px}#xsec{inset-block-end:14px;inset-inline-end:14px;width:330px}#xsec .closex{margin-inline-start:auto;border:0;background:transparent;color:var(--text-faint);font-size:16px}#xsec .body{padding:0 14px 13px}#xsec svg{width:100%;display:block;border-radius:9px;border:1px solid var(--border)}#xsec .leg{display:flex;flex-wrap:wrap;gap:10px;margin-top:10px;font-size:11px;color:var(--text-dim)}#xsec .leg i{display:inline-block;width:9px;height:9px;border-radius:2px;margin-inline-end:5px;vertical-align:middle}@keyframes magmaRise{0%,to{transform:translateY(2px);opacity:.85}50%{transform:translateY(-3px);opacity:1}}@keyframes driftL{0%,to{transform:translate(0)}50%{transform:translate(-5px)}}@keyframes 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14px;margin:0;font-size:11.5px;line-height:1.7;color:var(--text-faint)}.hint{position:absolute;inset-block-end:96px;inset-inline:0;margin:auto;width:max-content;max-width:90%;background:var(--surface-1);border:1px solid var(--border);border-radius:20px;padding:7px 16px;font-size:12px;color:var(--text-dim);box-shadow:var(--elev-2);z-index:4;pointer-events:none;animation:fade 1s ease 6s forwards}@keyframes fade{to{opacity:0}}.banner{position:absolute;inset-block-start:60px;inset-inline-end:14px;z-index:4;background:var(--panel);border:1px solid var(--border);border-radius:20px;padding:7px 15px;font-size:11.5px;color:var(--text-dim);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);box-shadow:var(--elev-1)}.banner b{color:var(--brand-press)}.mobile-hint{position:fixed;inset-block-start:60px;inset-inline:10px;z-index:22;margin-inline:auto;width:max-content;max-width:calc(100% - 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rgba(255,255,255,.95);transform:translate(50%)}.lbl3d.sea{color:#1a5b8f;font-style:italic}.lbl3d.plate{color:var(--brand-press);font-weight:700;font-size:calc(13px * var(--fs))}.lbl3d.city{font-size:calc(11px * var(--fs));font-weight:600}.lbl3d.city:before{content:"◉ ";color:var(--brand);opacity:.9}.lbl3d.faint{color:var(--fg-3);font-weight:500}.bnd-label{font-family:inherit;cursor:pointer;border:1px solid;border-radius:7px;background:#ffffffe0;padding:3px 9px;font-size:calc(11px * var(--fs));font-weight:600;white-space:nowrap;pointer-events:auto;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);box-shadow:var(--elev-1)}.bnd-label.divergent{color:#c2410c;border-color:#ff6b4a99}.bnd-label.convergent{color:var(--brand);border-color:#1e56e080}.bnd-label.transform{color:#a16207;border-color:#d4a01799}#legend{position:absolute;inset-block-end:14px;inset-inline-start:14px;z-index:5;padding:11px 14px;font-size:12px}.leg-sec{margin-bottom:10px}.leg-sec:last-child{margin-bottom:0}.leg-sec b{display:block;margin-bottom:7px;font-size:calc(12px * var(--fs));color:var(--fg-1)}.leg-sec span{display:flex;align-items:center;gap:8px;color:var(--text-dim);margin:5px 0;font-size:calc(11.5px * var(--fs))}.leg-sec i{width:18px;height:4px;border-radius:2px;display:inline-block;flex:0 0 auto}.leg-scale{display:flex;gap:12px}.leg-scale span{margin:0;gap:5px}.leg-scale i.dot{width:11px;height:11px;border-radius:50%}@media (max-width: 760px){#legend{display:none}}#volcano-lab{left:50%;top:52%;transform:translate(-50%,-50%);width:400px}#volcano-lab .closex{margin-inline-start:auto;border:0;background:transparent;color:var(--text-faint);font-size:16px}#volcano-lab .closex:hover{color:var(--fg-1)}.lab-canvas{height:240px;margin:0 14px;border-radius:10px;overflow:hidden;border:1px solid var(--border)}.lab-canvas canvas{display:block}.lab-controls{padding:11px 15px 4px}.lab-controls .lbl{display:flex;justify-content:space-between;font-size:calc(12.5px * var(--fs));color:var(--text-dim);margin-bottom:8px}.lab-controls .lbl b{color:var(--accent-teal);font-weight:600}.silica{-webkit-appearance:none;-moz-appearance:none;appearance:none;width:100%;height:5px;border-radius:5px;outline:none;background:linear-gradient(90deg,#c24a2a,#d98a3a,#8a8079)}.silica::-webkit-slider-thumb{-webkit-appearance:none;width:16px;height:16px;border-radius:50%;background:#fff;cursor:pointer;box-shadow:0 0 0 3px #0b12202e}.lab-ticks{display:flex;justify-content:space-between;font-size:10px;color:var(--text-faint);margin-top:6px}.lab-form{margin-top:10px;font-size:calc(12.5px * var(--fs));color:var(--text-dim)}.lab-form b{color:var(--accent-teal)}.lab-form small{display:block;color:var(--text-faint);margin-top:3px}#volcano-lab .leg{display:flex;flex-wrap:wrap;gap:10px;padding:10px 15px 14px;font-size:11.5px;color:var(--text-dim)}#volcano-lab .leg i{display:inline-block;width:9px;height:9px;border-radius:2px;margin-inline-end:5px;vertical-align:middle}@media (max-width: 760px){#volcano-lab{width:min(94vw,400px)}.lab-canvas{height:210px}}.wave-key{display:flex;gap:10px;white-space:nowrap;background:#ffffffe6;border:1px solid var(--border);border-radius:8px;padding:4px 10px;font-size:calc(11px * var(--fs));font-weight:600;pointer-events:none;box-shadow:var(--elev-1)}body.classroom{--fs: 1.3}body.classroom .panel{background:#fffffff5;border-color:var(--border-strong)}body.classroom .adv{display:none!important}.menu-btn{display:none;font-size:18px;padding:6px 12px}.drawer-close{display:none;margin-inline-start:auto;border:0;background:transparent;color:var(--text-faint);font-size:16px}@media (max-width: 760px){:root{--fs: 1.06}.menu-btn{display:grid;place-items:center}.drawer-close{display:block}.lesson,.brand b,.brand span{display:none}.topbar{gap:6px;padding:0 8px}.hint,.banner,.subject-switch button .btxt,.act .btxt,.demo-badge 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8px}.sw{width:42px;height:24px}.sw:after{width:20px;height:20px}.sw.on:after{inset-inline-end:20px}}::-webkit-scrollbar{width:8px}::-webkit-scrollbar-thumb{background:#0b122029;border-radius:8px}.subject-switch{display:flex;gap:4px;background:var(--surface-3);border-radius:10px;padding:3px}.subject-switch button{border:0;background:transparent;border-radius:8px;padding:6px 12px;font-size:calc(12px * var(--fs));color:var(--fg-3);font-weight:600}.subject-switch button.on{background:var(--surface-1);color:var(--brand-press);box-shadow:var(--elev-1)}.modlist{padding:4px 9px 8px;display:flex;flex-direction:column;gap:4px}.modrow{display:flex;align-items:center;gap:10px;width:100%;text-align:start;border:1px solid transparent;background:transparent;border-radius:9px;padding:8px 9px}.modrow:hover{background:var(--surface-2)}.modrow.on{background:var(--brand-soft);border-color:transparent}.modrow 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var(--fs));font-weight:600;color:var(--fg-1);white-space:nowrap;pointer-events:auto;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);box-shadow:var(--elev-1);transform:translate(50%)}.org-label:hover{background:#fff}.org-label.sel{box-shadow:0 0 0 2px #fff9,0 4px 16px #0b122047;font-weight:700}.phase-chip{background:#0b1220c7;color:#fff;padding:5px 14px;border-radius:20px;font-size:calc(13px * var(--fs));font-weight:700;white-space:nowrap;transform:translate(50%)}.side-tag{background:#ffffffd9;color:var(--fg-2);padding:3px 10px;border-radius:7px;font-size:calc(11px * var(--fs));font-weight:600;white-space:nowrap;transform:translate(50%)}.mol-tag{background:#9fd4ffeb;color:#0b3a5a;padding:2px 8px;border-radius:6px;font-size:calc(10.5px * var(--fs));font-weight:700;white-space:nowrap;transform:translate(50%)}.mol-tag.out{background:#ffd27aeb;color:#5a3a0b}.mol-tag.click{border:1px solid 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transparent;outline-offset:2px}.qtile:hover{transform:translateY(-2px);box-shadow:var(--elev-3)}.qtile.picked{outline-color:var(--fg-1);transform:scale(1.02)}.qshape{font-size:15px;opacity:.85}.quiz-reveal-btn{margin-top:16px;width:100%;border:0;border-radius:13px;background:var(--fg-1);color:#fff;font-weight:700;font-size:calc(16px * var(--fs));padding:15px}.quiz-reveal-btn:disabled{opacity:.35}.quiz-reveal-btn:not(:disabled):hover{background:#000}.quiz-reveal{inset-block-end:14px;inset-inline-start:50%;transform:translate(50%);width:min(720px,calc(100vw - 28px));padding:14px 18px;z-index:40}.qr-verdict{font-size:calc(16px * var(--fs));font-weight:700}.qr-verdict.right{color:#12805c}.qr-verdict.wrong{color:#b91c1c}.qr-explain{margin:7px 0;font-size:calc(14px * var(--fs));line-height:1.8;color:var(--fg-2)}.qr-note{font-size:calc(12.5px * var(--fs));color:var(--accent-teal);font-weight:600;margin-bottom:10px}.qr-nav{display:flex;gap:9px}.qact{border:1px solid 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var(--fs));padding:14px}}.exam-view{position:fixed;top:0;right:0;bottom:0;left:0;z-index:60;overflow:auto;background:#4b5568;padding:26px 14px}.exam-tools{position:sticky;top:0;z-index:2;display:flex;gap:10px;justify-content:center;margin-bottom:16px}.exam-tools .qact{box-shadow:var(--elev-3)}.exam-sheet{background:#fff;color:#101828;width:min(820px,96vw);margin:0 auto 30px;padding:40px 48px 30px;border-radius:4px;box-shadow:var(--elev-4);font-size:15px;line-height:1.9}.exam-head{display:flex;justify-content:space-between;align-items:flex-start;border-bottom:2.5px solid #1E56E0;padding-bottom:12px}.exam-brand b{font-size:26px;color:#1e56e0;display:block;line-height:1.1}.exam-brand span{font-size:11px;color:#667085}.exam-meta{text-align:start;font-size:12.5px;color:#344054}.exam-fields{display:flex;gap:26px;flex-wrap:wrap;font-size:13px;color:#344054;margin:14px 0 4px}.exam-title{font-size:20px;text-align:center;margin:14px 0 4px;color:#101828}.exam-inst{text-align:center;margin:0 0 14px;color:#344054;font-size:13.5px}.exam-marks{color:#1e56e0;font-weight:600}.exam-qs{margin:0;padding:0;list-style:none}.exam-qs li{margin-bottom:16px;break-inside:avoid}.exam-q{font-weight:700;margin-bottom:6px}.exam-choices{display:grid;grid-template-columns:1fr 1fr;gap:4px 26px;padding-inline-start:18px;font-size:14px}.exam-key{border:1.5px dashed #98a2b3;border-radius:8px;padding:10px 14px;margin-top:22px;font-size:13px;color:#344054}.exam-key b{display:block;margin-bottom:4px;color:#1e56e0}.exam-foot{margin-top:18px;padding-top:10px;border-top:1px solid #e4e7ec;font-size:11.5px;color:#667085;text-align:center}@media print{body *{visibility:hidden}.exam-view,.exam-view *{visibility:visible}.exam-view{position:absolute;top:0;right:0;bottom:0;left:0;background:#fff;padding:0;overflow:visible}.exam-tools{display:none}.exam-sheet{box-shadow:none;width:100%;padding:10mm 12mm}}.retry-btn{margin-top:6px;border:1px solid var(--brand);background:var(--brand);color:var(--brand-fg);border-radius:10px;padding:10px 22px;font-size:14px;font-weight:600}.retry-btn:hover{background:var(--brand-hover)}.demo-badge{display:inline-flex;align-items:center;text-decoration:none;border:1px dashed var(--brand);color:var(--brand);background:transparent;border-radius:20px;padding:6px 12px;font-size:11.5px;font-weight:600;white-space:nowrap}.demo-badge:hover{background:var(--brand-soft)}body.classroom .demo-badge{display:none}.onboarding{position:fixed;top:0;right:0;bottom:0;left:0;z-index:40;display:flex;align-items:center;justify-content:center;padding:24px;background:#0b122080;-webkit-backdrop-filter:blur(6px);backdrop-filter:blur(6px)}.onboarding-card{max-width:440px;width:100%;max-height:90dvh;overflow-y:auto;background:var(--panel);border:1px solid var(--border);border-radius:20px;padding:26px 26px 22px;box-shadow:var(--elev-4);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);text-align:right}.onb-pill{display:inline-block;background:var(--brand-soft);color:var(--brand-press);border-radius:20px;padding:4px 12px;font-size:12px;font-weight:700;letter-spacing:.3px}.onboarding-card h2{margin:14px 0 8px;font-size:21px;font-weight:700;color:var(--fg-1)}.onboarding-card p{margin:0 0 10px;font-size:14.5px;line-height:1.7;color:var(--text)}.onboarding-card p b{color:var(--fg-1)}.onb-steps{margin:4px 0 12px;padding-inline-start:20px;display:flex;flex-direction:column;gap:7px}.onb-steps li{font-size:13.5px;line-height:1.6;color:var(--text-dim)}.onb-steps li b{color:var(--brand)}.onb-more{font-size:13px;color:var(--text-dim);border-top:1px solid var(--border);padding-top:12px}.onb-actions{display:flex;gap:10px;margin-top:6px}.onb-primary{flex:1;border:none;background:var(--brand);color:var(--brand-fg);border-radius:12px;padding:12px 18px;font-size:15px;font-weight:600}.onb-primary:hover{background:var(--brand-hover)}.onb-ghost{display:inline-flex;align-items:center;justify-content:center;text-decoration:none;border:1px solid var(--border-strong);color:var(--text);border-radius:12px;padding:12px 18px;font-size:14px;font-weight:500}.onb-ghost:hover{border-color:var(--brand);color:var(--brand)}