/* ============================================================ My STEM Lab — LMS Design System Kid-friendly, accessible, responsive. Shared across all pages. ============================================================ */ :root{ /* Brand & palette — matched to the MyStemLab logo */ --brand:#0090c0; /* logo cyan-blue */ --brand-dark:#0a6f96; --brand-light:#e2f5fb; --accent:#d81818; /* logo red */ --accent-dark:#b01212; --accent-2:#ffc21f; /* warm highlight */ --magenta:#a81860; /* logo magenta */ --magenta-dark:#86134c; --indigo:#484890; /* logo indigo */ --indigo-dark:#363672; --cyan:#0090c0; --green:#1bb673; --green-dark:#0e8f59; --blue:#0090c0; --pink:#a81860; --purple:#484890; --ink:#222a3d; --ink-soft:#5a6376; --paper:#ffffff; --bg:#eef6fb; --card:#ffffff; --line:#dde7ef; --shadow:0 12px 34px rgba(20,70,100,.14); --shadow-sm:0 5px 16px rgba(20,70,100,.10); --radius:22px; --radius-sm:13px; --maxw:1120px; --font:"Baloo 2","Comic Neue",system-ui,"Segoe UI",Roboto,sans-serif; --font-body:"Nunito",system-ui,"Segoe UI",Roboto,sans-serif; } /* Grade accent theming (set data-grade on ) — drawn from logo palette */ body[data-grade="6"]{--theme:var(--cyan);--theme-dark:var(--brand-dark);} body[data-grade="7"]{--theme:var(--indigo);--theme-dark:var(--indigo-dark);} body[data-grade="8"]{--theme:var(--magenta);--theme-dark:var(--magenta-dark);} body[data-grade="9"]{--theme:var(--accent);--theme-dark:var(--accent-dark);} body[data-grade="10"]{--theme:#00708f;--theme-dark:#015873;} body{--theme:var(--brand);--theme-dark:var(--brand-dark);} *{box-sizing:border-box} html{scroll-behavior:smooth} body{ margin:0;font-family:var(--font-body);color:var(--ink); background: radial-gradient(1200px 520px at 82% -12%, #ffe3e0 0, transparent 60%), radial-gradient(1000px 520px at -12% 8%, #def0fa 0, transparent 58%), radial-gradient(800px 600px at 50% 120%, #f6e3ef 0, transparent 60%), var(--bg); line-height:1.55;-webkit-font-smoothing:antialiased; } h1,h2,h3,h4,.display{font-family:var(--font);line-height:1.15;margin:.2em 0 .4em} a{color:var(--brand-dark);text-decoration:none} img{max-width:100%} /* Layout helpers */ .wrap{max-width:var(--maxw);margin:0 auto;padding:0 18px} .row{display:flex;gap:16px;flex-wrap:wrap} .center{text-align:center} .muted{color:var(--ink-soft)} .pill{display:inline-block;padding:4px 12px;border-radius:999px;font-weight:800;font-size:.8rem} /* ---------- Top nav ---------- */ .topbar{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.85); backdrop-filter:blur(10px);border-bottom:1px solid var(--line)} .topbar .wrap{display:flex;align-items:center;gap:14px;height:64px} .logo{display:flex;align-items:center;gap:10px;font-family:var(--font);font-weight:800; font-size:1.15rem;color:var(--ink)} .logo .mark{width:38px;height:38px;border-radius:11px;display:grid;place-items:center; background:linear-gradient(135deg,var(--brand),var(--accent));color:#fff;font-size:1.2rem; box-shadow:var(--shadow-sm)} .topbar .spacer{flex:1} .crumbs{font-size:.92rem;color:var(--ink-soft);font-weight:700} .crumbs a{color:var(--ink-soft)} .crumbs a:hover{color:var(--brand-dark)} /* ---------- Buttons ---------- */ .btn{appearance:none;border:none;cursor:pointer;font-family:var(--font);font-weight:800; font-size:1rem;padding:12px 22px;border-radius:14px;color:#fff; background:linear-gradient(135deg,var(--theme),var(--theme-dark)); box-shadow:0 6px 0 rgba(0,0,0,.12),var(--shadow-sm);transition:transform .08s,box-shadow .08s; display:inline-flex;align-items:center;gap:8px} .btn:active{transform:translateY(3px);box-shadow:0 3px 0 rgba(0,0,0,.12)} .btn.ghost{background:#fff;color:var(--theme-dark);border:2px solid var(--line);box-shadow:var(--shadow-sm)} .btn.small{padding:8px 14px;font-size:.9rem;border-radius:11px} .btn[disabled]{opacity:.5;cursor:not-allowed;filter:grayscale(.4)} /* ---------- Hero ---------- */ .hero{padding:42px 0 14px} .hero h1{font-size:clamp(2rem,4.5vw,3.4rem)} .hero p.lead{font-size:1.15rem;color:var(--ink-soft);max-width:640px} .kicker{font-family:var(--font);font-weight:800;letter-spacing:.04em;text-transform:uppercase; color:var(--theme-dark);font-size:.85rem} /* ---------- Cards / grid ---------- */ .grid{display:grid;gap:18px} .grid.g-grades{grid-template-columns:repeat(auto-fill,minmax(200px,1fr))} .grid.g-acts{grid-template-columns:repeat(auto-fill,minmax(250px,1fr))} .card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius); box-shadow:var(--shadow-sm);overflow:hidden;transition:transform .12s,box-shadow .12s;position:relative} a.card:hover,.card.hoverable:hover{transform:translateY(-4px);box-shadow:var(--shadow)} .card .body{padding:18px} .card .badge{position:absolute;top:12px;right:12px;background:var(--accent-2);color:#5a3d00; font-weight:800;font-size:.72rem;padding:4px 10px;border-radius:999px} .card .topart{height:96px;display:grid;place-items:center;font-size:2.6rem; background:linear-gradient(135deg,var(--theme),var(--theme-dark));color:#fff} .card h3{margin:.1em 0 .25em;font-size:1.12rem} .card .meta{font-size:.82rem;color:var(--ink-soft);font-weight:700} .card .tag{display:inline-block;font-size:.72rem;font-weight:800;padding:3px 9px;border-radius:999px; background:var(--brand-light);color:var(--brand-dark);margin:6px 6px 0 0} .grade-card .topart{font-size:3rem} .grade-card.locked{opacity:.62;filter:grayscale(.3)} .grade-card.locked .badge{background:#dfe3f2;color:#6b7299} /* ---------- Activity page sections ---------- */ .act-hero{padding:30px 0 6px} .act-hero .emoji{font-size:3rem} .section{background:var(--card);border:1px solid var(--line);border-radius:var(--radius); box-shadow:var(--shadow-sm);padding:24px;margin:18px 0} .section > h2{display:flex;align-items:center;gap:12px;font-size:1.5rem;margin-top:0} .section > h2 .num{width:38px;height:38px;flex:0 0 38px;border-radius:11px;display:grid;place-items:center; background:linear-gradient(135deg,var(--theme),var(--theme-dark));color:#fff;font-size:1.05rem;font-weight:800} .section-sub{color:var(--ink-soft);margin-top:-4px} /* concept chips */ .chips{display:flex;flex-wrap:wrap;gap:10px;margin:10px 0} .chip{background:var(--brand-light);color:var(--brand-dark);font-weight:800;padding:8px 14px; border-radius:12px;font-size:.92rem;border:1px solid #d9d4ff} .chip.sci{background:#e7f9ef;color:var(--green-dark);border-color:#bdeccf} .chip.math{background:#fff2dc;color:#a86b00;border-color:#ffe0a8} /* outcome list */ .outcomes{list-style:none;padding:0;margin:8px 0} .outcomes li{display:flex;gap:12px;padding:10px 0;border-bottom:1px dashed var(--line)} .outcomes li:last-child{border-bottom:none} .outcomes .tick{flex:0 0 26px;width:26px;height:26px;border-radius:8px;background:var(--green); color:#fff;display:grid;place-items:center;font-weight:900;font-size:.9rem} .ncert{display:inline-block;font-size:.74rem;font-weight:800;background:#eef;color:#3b2fc7; padding:2px 8px;border-radius:6px;margin-left:6px} /* fact / scientist boxes */ .factbox{display:flex;gap:14px;background:linear-gradient(135deg,#fff8ec,#fff);border:1px solid #ffe6bd; border-radius:16px;padding:16px;margin:12px 0} .factbox .ic{font-size:1.8rem} .scientist{display:flex;gap:16px;align-items:flex-start;background:#f7f5ff;border:1px solid #e3ddff; border-radius:16px;padding:16px;margin:12px 0} .scientist .avatar{flex:0 0 64px;width:64px;height:64px;border-radius:50%;display:grid;place-items:center; font-size:2rem;background:linear-gradient(135deg,var(--purple),var(--brand));color:#fff} /* DIY manual steps */ .steps{counter-reset:step;list-style:none;padding:0;margin:10px 0} .steps li{position:relative;padding:14px 14px 14px 60px;background:#fbfcff;border:1px solid var(--line); border-radius:14px;margin-bottom:10px} .steps li::before{counter-increment:step;content:counter(step);position:absolute;left:14px;top:14px; width:32px;height:32px;border-radius:10px;background:linear-gradient(135deg,var(--theme),var(--theme-dark)); color:#fff;display:grid;place-items:center;font-weight:800;font-family:var(--font)} .steps li b{display:block} .materials{display:flex;flex-wrap:wrap;gap:8px;margin:10px 0} .materials .m{background:#eefcf4;border:1px solid #c7eed8;color:var(--green-dark);font-weight:700; padding:6px 12px;border-radius:10px;font-size:.88rem} .safety{background:#fff0f0;border:1px solid #ffd0d0;border-radius:14px;padding:12px 16px;margin:10px 0; color:#b22; font-weight:600} /* video placeholder */ .video-ph{position:relative;border-radius:16px;overflow:hidden;border:1px solid var(--line); background:linear-gradient(135deg,#2a2f4a,#444a73);aspect-ratio:16/9;display:grid;place-items:center; color:#fff;text-align:center;cursor:pointer} .video-ph .play{width:74px;height:74px;border-radius:50%;background:rgba(255,255,255,.16); border:3px solid #fff;display:grid;place-items:center;font-size:1.8rem;margin:0 auto 10px; transition:transform .12s} .video-ph:hover .play{transform:scale(1.08)} .video-ph small{opacity:.85} /* extensions */ .ext{display:flex;gap:12px;padding:12px;border:1px dashed var(--line);border-radius:14px;margin:10px 0; background:#fcfcff} .ext .lvl{flex:0 0 auto;align-self:flex-start;font-weight:800;font-size:.72rem;padding:4px 10px;border-radius:999px} .ext .lvl.e{background:#e7f9ef;color:var(--green-dark)} .ext .lvl.m{background:#fff2dc;color:#a86b00} .ext .lvl.h{background:#ffe7ef;color:#c0306a} /* ---------- Simulation shell ---------- */ .sim{border:1px solid var(--line);border-radius:18px;overflow:hidden;background:#fbfcff} .sim .stage{position:relative;background: linear-gradient(180deg,#eaf2ff,#f7faff);min-height:300px;display:block} .sim canvas{display:block;width:100%;touch-action:none} .sim .controls{display:flex;flex-wrap:wrap;gap:14px;align-items:center;padding:14px 16px;border-top:1px solid var(--line);background:#fff} .ctrl{display:flex;flex-direction:column;gap:4px;min-width:150px} .ctrl label{font-weight:800;font-size:.82rem;color:var(--ink-soft)} .ctrl output{font-weight:800;color:var(--theme-dark)} input[type=range]{width:100%;accent-color:var(--theme)} .readout{display:flex;flex-wrap:wrap;gap:10px;margin-top:10px} .readout .stat{background:#fff;border:1px solid var(--line);border-radius:12px;padding:8px 14px;min-width:90px} .readout .stat b{display:block;font-size:1.25rem;font-family:var(--font);color:var(--theme-dark)} .readout .stat span{font-size:.74rem;color:var(--ink-soft);font-weight:700} /* ---------- Quiz engine ---------- */ .quiz{margin-top:6px} .q{border:1px solid var(--line);border-radius:14px;padding:16px;margin-bottom:12px;background:#fff} .q .qtext{font-weight:800;margin-bottom:10px} .q .opts{display:grid;gap:8px} .opt{display:flex;align-items:center;gap:10px;padding:11px 14px;border:2px solid var(--line); border-radius:12px;cursor:pointer;font-weight:600;background:#fff;transition:.1s} .opt:hover{border-color:var(--theme)} .opt.correct{border-color:var(--green);background:#eafff3} .opt.wrong{border-color:#ff6b6b;background:#fff0f0} .opt.disabled{pointer-events:none;opacity:.85} .opt .mk{margin-left:auto;font-weight:900} .q .explain{margin-top:10px;padding:10px 12px;border-radius:10px;background:var(--brand-light); font-size:.92rem;display:none} .q.answered .explain{display:block} .quiz-result{display:none;text-align:center;padding:18px;border-radius:16px;background:#fff; border:1px solid var(--line);margin-top:8px} .quiz-result.show{display:block} .quiz-result .score{font-family:var(--font);font-size:2.4rem;color:var(--theme-dark)} .progressbar{height:10px;background:#eef;border-radius:999px;overflow:hidden;margin:6px 0 14px} .progressbar > i{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--theme),var(--theme-dark));transition:width .3s} /* ---------- Game engine (match / sort) ---------- */ .game-toolbar{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-bottom:12px} .scorechip{font-weight:800;background:var(--accent-2);color:#5a3d00;padding:6px 14px;border-radius:999px} /* matching game */ .match-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(110px,1fr));gap:12px} .tile{aspect-ratio:1;border-radius:14px;border:2px solid var(--line);background:#fff;cursor:pointer; display:grid;place-items:center;font-size:1.8rem;font-weight:800;user-select:none;transition:.12s; text-align:center;padding:6px} .tile.flipped{background:var(--brand-light);border-color:var(--theme)} .tile.matched{background:#eafff3;border-color:var(--green);cursor:default} .tile.small{font-size:.95rem} /* sorting / drag game */ .bins{display:grid;gap:14px;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));margin-top:12px} .bin{border:2px dashed var(--line);border-radius:16px;padding:12px;min-height:120px;background:#fbfcff} .bin.over{border-color:var(--theme);background:var(--brand-light)} .bin h4{margin:0 0 8px;text-align:center} .bin .drop{display:flex;flex-wrap:wrap;gap:8px;justify-content:center} .tokens{display:flex;flex-wrap:wrap;gap:10px;margin-top:10px;min-height:50px} .token{padding:9px 14px;border-radius:12px;background:#fff;border:2px solid var(--line);font-weight:700; cursor:grab;user-select:none} .token.dragging{opacity:.5} .token.placed{border-color:var(--green);background:#eafff3} /* toast */ .toast{position:fixed;left:50%;bottom:26px;transform:translateX(-50%) translateY(20px);opacity:0; background:var(--ink);color:#fff;padding:12px 20px;border-radius:14px;font-weight:800;z-index:200; transition:.25s;box-shadow:var(--shadow)} .toast.show{opacity:1;transform:translateX(-50%) translateY(0)} /* sticky section nav */ .secnav{position:sticky;top:64px;z-index:30;background:rgba(255,255,255,.9);backdrop-filter:blur(8px); border-bottom:1px solid var(--line);margin-bottom:8px} .secnav .wrap{display:flex;gap:6px;overflow-x:auto;padding:8px 18px} .secnav a{flex:0 0 auto;font-size:.82rem;font-weight:800;color:var(--ink-soft);padding:7px 12px; border-radius:10px;white-space:nowrap} .secnav a:hover{background:var(--brand-light);color:var(--brand-dark)} /* footer */ .footer{margin-top:30px;padding:26px 0;border-top:1px solid var(--line);color:var(--ink-soft);font-size:.9rem} .footer b{color:var(--ink)} /* confetti canvas */ #confetti{position:fixed;inset:0;pointer-events:none;z-index:150} /* responsive */ @media(max-width:640px){ .section{padding:18px} .hero{padding:28px 0 8px} .ctrl{min-width:130px} } .sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)} /* ============================================================ v2 additions: logo, image placeholders, gamification, HOTS ============================================================ */ /* ---------- brand logo ---------- */ .logo{gap:10px} .logo-img{height:46px;width:auto;display:block} .logo-mark{width:42px;height:42px;flex:0 0 42px;display:grid;place-items:center; border-radius:12px;background:linear-gradient(135deg,var(--brand),var(--accent)); box-shadow:var(--shadow-sm)} .logo-mark svg{width:30px;height:30px;display:block} .logo-word{font-family:var(--font);font-weight:800;font-size:1.18rem;color:var(--ink);line-height:1} .logo-word b{color:var(--brand-dark)} .logo-word small{display:block;font-size:.6rem;letter-spacing:.14em;font-weight:700; color:var(--ink-soft);text-transform:uppercase;margin-top:1px} @media(max-width:520px){.logo-word{display:none}} /* ---------- image placeholders ---------- */ .imgph{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center; gap:6px;border:2px dashed #c7cde6;border-radius:14px; background:repeating-linear-gradient(45deg,#fbfcff,#fbfcff 12px,#f3f5ff 12px,#f3f5ff 24px); color:var(--ink-soft);text-align:center;cursor:pointer;padding:12px;transition:.12s;min-height:90px} .imgph:hover{border-color:var(--theme);color:var(--theme-dark)} .imgph .imgph-ic{font-size:1.7rem;line-height:1} .imgph .imgph-cap{font-size:.76rem;font-weight:800} .imgph::after{content:"placeholder";position:absolute;top:6px;right:8px;font-size:.6rem;font-weight:800; letter-spacing:.06em;color:#aab2cc;text-transform:uppercase} .imgph.has-img{background:#fff;border:2px solid var(--line);padding:6px;cursor:default} .imgph.has-img::after{content:""} .imgph.has-img .imgph-ic,.imgph.has-img .imgph-cap{display:none} .imgph.has-img img{display:block;width:100%;height:auto;border-radius:10px} /* concept banner image */ .concept-img{width:100%;aspect-ratio:16/5;margin:0 0 14px} .concept-img .imgph-ic{font-size:2rem} /* DIY step images */ .steps li{display:flex;gap:14px;align-items:flex-start} .steps li .step-body{flex:1;min-width:0} .steps li .step-img{flex:0 0 116px;width:116px;min-height:78px;aspect-ratio:4/3;margin:0;align-self:center} @media(max-width:560px){.steps li{flex-direction:column}.steps li .step-img{width:100%;flex-basis:auto}} /* real-world factbox images */ .factbox{align-items:stretch} .factbox .fact-text{flex:1} .factbox .fact-img{flex:0 0 120px;width:120px;min-height:80px;aspect-ratio:4/3;margin:0;align-self:center} .scientist .sci-img{flex:0 0 120px;width:120px;min-height:90px;aspect-ratio:4/3;margin:0;align-self:center} @media(max-width:560px){.factbox{flex-wrap:wrap}.factbox .fact-img,.scientist .sci-img{width:100%;flex-basis:auto}} /* extension images */ .ext{align-items:stretch} .ext .ext-text{flex:1} .ext .ext-img{flex:0 0 110px;width:110px;min-height:74px;aspect-ratio:4/3;margin:0;align-self:center} @media(max-width:560px){.ext{flex-wrap:wrap}.ext .ext-img{width:100%;flex-basis:auto}} /* ---------- HOTS section ---------- */ .hots-grid{display:grid;gap:16px;grid-template-columns:1fr} .hots-card{display:flex;gap:16px;border:1px solid var(--line);border-radius:16px;padding:16px; background:linear-gradient(135deg,#fbf7ff,#fff)} .hots-card .hots-img{flex:0 0 150px;width:150px;min-height:110px;aspect-ratio:4/3;margin:0;align-self:flex-start} .hots-card .hots-body{flex:1} .hots-q{font-weight:800;font-size:1.02rem;margin-bottom:8px} .hots-q .hq{display:inline-grid;place-items:center;width:26px;height:26px;border-radius:8px;margin-right:8px; background:linear-gradient(135deg,var(--purple),var(--brand));color:#fff;font-size:.82rem;vertical-align:middle} details.hots-hint{margin-top:8px;border:1px solid var(--line);border-radius:10px;background:#fff;overflow:hidden} details.hots-hint summary{cursor:pointer;padding:9px 12px;font-weight:800;color:var(--theme-dark);font-size:.9rem;list-style:none} details.hots-hint summary::-webkit-details-marker{display:none} details.hots-hint summary::before{content:"💭 ";} details.hots-hint[open] summary::before{content:"💡 ";} details.hots-hint p{margin:0;padding:0 12px 12px;font-size:.92rem;color:var(--ink-soft)} @media(max-width:560px){.hots-card{flex-direction:column}.hots-card .hots-img{width:100%;flex-basis:auto}} /* ---------- gamification panel (quiz) ---------- */ .gamepanel{margin-top:16px;border:1px solid var(--line);border-radius:18px;overflow:hidden; background:linear-gradient(135deg,#fff,#fbfcff)} .gp-head{display:flex;gap:18px;flex-wrap:wrap;align-items:center;padding:16px 18px; background:linear-gradient(135deg,var(--theme),var(--theme-dark));color:#fff} .gp-score{display:flex;flex-direction:column;line-height:1} .gp-score .gp-pts{font-family:var(--font);font-size:2.3rem;font-weight:800} .gp-score .gp-lbl{font-size:.74rem;font-weight:700;opacity:.85;text-transform:uppercase;letter-spacing:.06em} .gp-name{display:flex;flex-direction:column;gap:3px} .gp-name label{font-size:.7rem;font-weight:800;opacity:.85;text-transform:uppercase;letter-spacing:.05em} .gp-name input{border:none;border-radius:9px;padding:7px 10px;font-weight:800;font-family:var(--font-body); width:150px;color:var(--ink)} .gp-prog{flex:1;min-width:160px;font-weight:700;font-size:.82rem} .gp-prog .progressbar{background:rgba(255,255,255,.35);margin-top:6px} .gp-prog .progressbar>i{background:#fff} .gp-badges,.gp-lb{padding:14px 18px} .gp-badges h4,.gp-lb h4{margin:0 0 10px;font-size:1rem} .badge-row{display:flex;flex-wrap:wrap;gap:8px} .badge{display:flex;align-items:center;gap:6px;border-radius:999px;padding:6px 12px;font-weight:800; font-size:.8rem;border:2px solid var(--line)} .badge .b-ic{font-size:1.05rem} .badge.got{background:#eafff3;border-color:var(--green);color:var(--green-dark)} .badge.locked{opacity:.45;filter:grayscale(.7)} .lb-list{border:1px solid var(--line);border-radius:12px;overflow:hidden} .lb-row{display:flex;align-items:center;gap:10px;padding:9px 14px;border-bottom:1px solid var(--line);font-weight:700} .lb-row:last-child{border-bottom:none} .lb-row .lb-rank{width:30px;font-weight:800} .lb-row .lb-name{flex:1} .lb-row .lb-pts{font-family:var(--font);font-weight:800;color:var(--theme-dark)} .lb-row.you{background:var(--brand-light)} .lb-row.you .lb-name{color:var(--brand-dark);font-weight:800} .gp-gain{color:var(--green-dark);font-weight:800} /* ============================================================ v3 additions: vibrance, video embeds, sim tabs, observation, one-question quiz, brand polish ============================================================ */ /* vibrant section headers + cards */ .section{border:1px solid var(--line);box-shadow:var(--shadow-sm)} .section > h2 .num{box-shadow:0 4px 10px rgba(0,0,0,.12)} .topbar{background:rgba(255,255,255,.92);border-bottom:2px solid var(--brand-light)} .act-hero h1{background:linear-gradient(90deg,var(--theme),var(--magenta));-webkit-background-clip:text;background-clip:text;color:transparent} .hero h1 span,.act-hero .emoji{filter:saturate(1.1)} .btn{box-shadow:0 6px 0 rgba(0,0,0,.14),var(--shadow-sm)} .card .topart{background:linear-gradient(135deg,var(--theme),var(--magenta))} .chip{transition:transform .1s} .chip:hover{transform:translateY(-2px) scale(1.03)} /* clickable concept/info cards reveal (onclick interactivity) */ .reveal-card{border:2px solid var(--line);border-radius:16px;padding:0;overflow:hidden;margin:10px 0;background:#fff;transition:.15s} .reveal-card > button.reveal-head{width:100%;text-align:left;border:none;background:linear-gradient(135deg,var(--brand-light),#fff); cursor:pointer;padding:14px 16px;font-family:var(--font);font-weight:800;font-size:1.02rem;color:var(--ink); display:flex;align-items:center;gap:10px} .reveal-card > button.reveal-head .twirl{margin-left:auto;transition:transform .2s;color:var(--theme-dark)} .reveal-card.open > button.reveal-head .twirl{transform:rotate(90deg)} .reveal-card .reveal-body{max-height:0;overflow:hidden;transition:max-height .3s ease;padding:0 16px} .reveal-card.open .reveal-body{max-height:1200px;padding:6px 16px 16px} /* ---------- simulation tabs ---------- */ .simtabs{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:12px} .simtab{appearance:none;border:2px solid var(--line);background:#fff;cursor:pointer;border-radius:13px; padding:9px 16px;font-family:var(--font);font-weight:800;font-size:.92rem;color:var(--ink-soft); display:flex;align-items:center;gap:7px;transition:.12s} .simtab:hover{border-color:var(--theme);transform:translateY(-2px)} .simtab.active{background:linear-gradient(135deg,var(--theme),var(--theme-dark));color:#fff;border-color:transparent; box-shadow:0 5px 14px rgba(0,0,0,.16)} .simpane{display:none;animation:fade .25s} .simpane.active{display:block} @keyframes fade{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}} /* ---------- video embed ---------- */ .video{position:relative;border-radius:18px;overflow:hidden;border:2px solid var(--line); background:#0c1230;aspect-ratio:16/9;box-shadow:var(--shadow-sm)} .video iframe{position:absolute;inset:0;width:100%;height:100%;border:0} .video .facade{position:absolute;inset:0;display:grid;place-items:center;cursor:pointer; background:linear-gradient(135deg,#10204a,#243a6b);color:#fff;text-align:center} .video .facade:hover .pbtn{transform:scale(1.1);background:var(--accent)} .video .facade .pbtn{width:82px;height:82px;border-radius:50%;background:rgba(216,24,24,.92);display:grid;place-items:center; font-size:2rem;margin:0 auto 12px;transition:.15s;box-shadow:0 8px 24px rgba(0,0,0,.4)} .video .facade b{font-size:1.05rem} .video .facade small{opacity:.85;display:block;margin-top:4px} .video-row{display:flex;gap:8px;align-items:center;margin-top:10px;flex-wrap:wrap} .video-link{font-weight:800;font-size:.86rem;color:var(--brand-dark)} /* ---------- observation section ---------- */ .obs{border:2px dashed var(--theme);border-radius:18px;padding:18px;margin:14px 0; background:linear-gradient(135deg,#fffdf5,#fff)} .obs h3{margin:0 0 4px;display:flex;align-items:center;gap:8px} .obs-table{display:grid;gap:10px;margin-top:12px} .obs-item{background:#fff;border:1px solid var(--line);border-radius:14px;padding:12px 14px} .obs-item .obs-q{font-weight:800;margin-bottom:8px;display:flex;gap:8px} .obs-item textarea{width:100%;border:2px solid var(--line);border-radius:10px;padding:9px 11px; font-family:var(--font-body);font-size:.95rem;resize:vertical;min-height:54px} .obs-item textarea:focus{outline:none;border-color:var(--theme)} .obs-item details{margin-top:8px} .obs-item details summary{cursor:pointer;font-weight:800;color:var(--theme-dark);font-size:.88rem;list-style:none} .obs-item details summary::-webkit-details-marker{display:none} .obs-item details summary::before{content:"👀 "} .obs-item details[open] summary::before{content:"✅ "} .obs-item details p{margin:6px 0 0;font-size:.92rem;color:var(--ink-soft); background:var(--brand-light);padding:9px 11px;border-radius:9px} /* ---------- one-question quiz ---------- */ .quiz-stage{min-height:60px} .qmeta{display:flex;align-items:center;justify-content:space-between;margin-bottom:8px;font-weight:800;color:var(--ink-soft);font-size:.86rem} .qnav{display:flex;justify-content:flex-end;margin-top:14px} .qnav .btn[disabled]{display:none} .q .opt .mk{font-size:1.1rem} .qdots{display:flex;gap:6px} .qdots i{width:10px;height:10px;border-radius:50%;background:#cfe4ee;display:inline-block;transition:.2s} .qdots i.done{background:var(--theme)} .qdots i.right{background:var(--green)} .qdots i.wrong{background:var(--accent)} .qdots i.cur{box-shadow:0 0 0 3px rgba(0,144,192,.25)} /* motion-facing icons helper */ .face-right{display:inline-block} .face-left{display:inline-block;transform:scaleX(-1)} /* ============================================================ v4: larger image placeholders + crisp canvases ============================================================ */ .imgph{min-height:130px} .imgph .imgph-ic{font-size:2.3rem} .imgph .imgph-cap{font-size:.84rem} .concept-img{aspect-ratio:16/6;min-height:180px} .concept-img .imgph-ic{font-size:2.8rem} .steps li .step-img{flex:0 0 170px;width:170px;min-height:120px} .factbox .fact-img{flex:0 0 190px;width:190px;min-height:130px} .scientist .sci-img{flex:0 0 190px;width:190px;min-height:140px} .ext .ext-img{flex:0 0 170px;width:170px;min-height:118px} .hots-card .hots-img{flex:0 0 210px;width:210px;min-height:160px} .obs-item .obs-img{min-height:120px} /* crisp supersampled canvases */ .sim canvas{image-rendering:auto} @media(max-width:560px){ .steps li .step-img,.factbox .fact-img,.scientist .sci-img,.ext .ext-img,.hots-card .hots-img{width:100%;flex-basis:auto} } /* ============================================================ v5: real image slots (figure-or-placeholder) + mobile-friendly ============================================================ */ .figph{margin:14px 0;border-radius:18px;overflow:hidden;border:2px solid var(--line); background:#fff;box-shadow:var(--shadow-sm);position:relative} .figph img{display:block;width:100%;height:auto} .figph figcaption{display:none} .figph.missing{border-style:dashed;border-color:#c2cae0; background:repeating-linear-gradient(45deg,#fbfcff,#fbfcff 14px,#eef3fb 14px,#eef3fb 28px)} .figph.missing figcaption{display:flex;flex-direction:column;align-items:center;justify-content:center; gap:8px;min-height:190px;padding:22px;text-align:center;color:var(--ink-soft);font-weight:700} .figph.missing figcaption .fic{font-size:2.6rem;line-height:1} .figph.missing figcaption b{color:var(--ink);font-size:1rem} .figph.missing figcaption code{background:#fff;border:1px solid var(--line);border-radius:7px; padding:3px 9px;font-weight:800;color:var(--brand-dark);font-size:.86rem} .figph.concept-fig.missing figcaption{min-height:230px} .fig-grid{display:grid;gap:16px;grid-template-columns:1fr 1fr} @media(max-width:760px){.fig-grid{grid-template-columns:1fr}} .fig-stack{margin:12px 0;border-radius:18px;overflow:hidden;border:2px solid var(--line); background:#fff;box-shadow:var(--shadow-sm)} .fig-stack .figph{margin:0;border:0;border-radius:0;box-shadow:none} .fig-stack .figph + .figph{border-top:1px solid var(--line)} /* ---------------- MOBILE-FRIENDLY ---------------- */ @media(max-width:760px){ .wrap{padding:0 14px} .section{padding:18px;border-radius:18px} .section>h2{font-size:1.25rem} .act-hero h1,.hero h1{font-size:clamp(1.6rem,7vw,2.2rem)} .readout{gap:8px} .readout .stat{min-width:78px;padding:7px 10px} .readout .stat b{font-size:1.05rem} .gp-head{gap:12px} .gp-score .gp-pts{font-size:1.8rem} .sim .controls{gap:12px;padding:12px} .ctrl{min-width:120px;flex:1 1 140px} .video iframe{position:absolute} } @media(max-width:480px){ .topbar .wrap{height:56px;gap:8px} .logo-img{height:38px} .crumbs{font-size:.78rem} .secnav .wrap{padding:7px 12px;gap:4px} .secnav a{font-size:.78rem;padding:6px 9px} .section{padding:14px} .section>h2{font-size:1.12rem;gap:8px} .section>h2 .num{width:30px;height:30px;flex-basis:30px;font-size:.9rem} .chip{font-size:.84rem;padding:7px 11px} .btn{padding:11px 18px;font-size:.95rem} .simtab{padding:8px 12px;font-size:.85rem} .ctrl{min-width:100%;flex-basis:100%} .sim .controls select,.sim .controls input[type=number]{width:100%} .readout{flex-wrap:wrap} .readout .stat{flex:1 1 44%;min-width:0} .obs-item textarea{min-height:64px} .steps li{flex-direction:column} .steps li .step-img{width:100%} .grid.g-acts{grid-template-columns:1fr} .grid.g-grades{grid-template-columns:1fr 1fr} .gp-head{flex-direction:column;align-items:flex-start} .badge-row{gap:6px} .badge{font-size:.74rem;padding:5px 9px} .hots-card{flex-direction:column} .figph.missing figcaption{min-height:150px;padding:16px} } /* larger, comfortable tap targets on touch devices */ @media(hover:none){ .opt{padding:13px 15px} .simtab,.btn{min-height:42px} } /* v5b: DIY step image slots */ .steps li .step-fig{flex:0 0 210px;width:210px;margin:0;align-self:center;border-radius:14px} .steps li .step-fig img{border-radius:12px} .steps li .step-fig.missing figcaption{min-height:120px;padding:14px;gap:6px} .steps li .step-fig.missing figcaption .fic{font-size:1.9rem} .steps li .step-fig.missing figcaption code{font-size:.74rem} @media(max-width:560px){.steps li .step-fig{width:100%;flex-basis:auto}}