:root{
  --bg:#f4f8fb;--panel:#fff;--ink:#17324d;--muted:#6b7e8e;--line:#dce7ee;
  --blue:#2f80ed;--blue-dark:#1f5fae;--green:#2fa66a;--green-soft:#e9f7ef;
  --amber-soft:#fff7df;--shadow:0 16px 40px rgba(31,64,88,.10);--radius:20px;
}
*{box-sizing:border-box} html{scroll-behavior:smooth}
body{margin:0;color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:radial-gradient(circle at 0 0,rgba(47,128,237,.08),transparent 28rem),linear-gradient(180deg,#f9fbfd,#eef5f9)}
button,input,textarea{font:inherit} button{color:inherit}
button:focus-visible,textarea:focus-visible,input:focus-visible,a:focus-visible{outline:3px solid rgba(47,128,237,.28);outline-offset:2px}
.site-header,.page-shell,.site-footer{width:min(1240px,calc(100% - 32px));margin-left:auto;margin-right:auto}
.site-header{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:24px 0 10px}
.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink)}
.brand-mark{width:44px;height:44px;border-radius:13px;display:grid;place-items:center;color:#fff;background:linear-gradient(135deg,var(--blue),#55a9f5);font-weight:900;letter-spacing:-1px;box-shadow:0 8px 20px rgba(47,128,237,.25)}
.brand strong{display:block}.brand small{display:block;color:var(--muted);font-size:.72rem;margin-top:2px}
.home-link{text-decoration:none;color:var(--blue-dark);font-weight:800;padding:9px 12px;border-radius:11px}.home-link:hover{background:#eaf3ff}
.page-shell{padding-bottom:38px}
.hero{margin:18px 0 16px;display:grid;grid-template-columns:minmax(0,1.6fr) minmax(280px,.62fr);gap:24px;align-items:stretch}
.hero-copy,.mission-card,.panel,.formula-card,.step-nav{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
.hero-copy{padding:32px 34px;background:radial-gradient(circle at 90% 10%,rgba(117,103,179,.08),transparent 20rem),linear-gradient(135deg,#fff,#f7fbff)}
.eyebrow,.section-kicker,.panel-kicker,.mission-kicker,.formula-label{margin:0;color:var(--blue-dark);font-size:.72rem;font-weight:900;letter-spacing:.11em;text-transform:uppercase}
.hero h1{margin:8px 0 11px;font-size:clamp(2rem,4vw,3.5rem);letter-spacing:-.045em;line-height:1.02}
.hero-copy>p:not(.eyebrow){max-width:820px;margin:0;color:var(--muted);line-height:1.65;font-size:1rem}
.hero-chips{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.hero-chips span{font-size:.72rem;font-weight:800;color:#435d72;background:#eff5f8;border:1px solid #dce8ef;border-radius:999px;padding:7px 10px}
.mission-card{padding:25px;display:flex;flex-direction:column;justify-content:center;background:linear-gradient(145deg,#eef6ff,#f7f4ff)}
.mission-card strong{font-size:1.1rem;line-height:1.45;margin:8px 0 12px}.mission-card small{color:var(--muted)}
.step-nav{margin-bottom:20px;padding:6px;display:grid;grid-template-columns:repeat(5,1fr);gap:6px}
.step-tab{border:0;background:transparent;cursor:pointer;border-radius:14px;padding:12px 10px;display:grid;grid-template-columns:auto 1fr;column-gap:9px;text-align:left;align-items:center}
.step-tab>span{grid-row:1/3;width:30px;height:30px;border-radius:50%;background:#eaf1f5;color:#607484;display:grid;place-items:center;font-weight:900;font-size:.75rem}
.step-tab strong{font-size:.78rem}.step-tab small{color:var(--muted);font-size:.64rem;margin-top:1px}
.step-tab.active{background:#edf5ff}.step-tab.active>span{background:var(--blue);color:#fff}.step-tab.completed>span{background:var(--green);color:#fff}.step-tab.locked{opacity:.48;cursor:not-allowed}
.step-section{display:none}.step-section.active{display:block}
.section-heading{display:flex;justify-content:space-between;gap:22px;align-items:flex-start;margin:4px 2px 16px}
.section-heading h2{margin:5px 0 7px;font-size:1.65rem;letter-spacing:-.02em}
.section-heading>div>p:not(.section-kicker){margin:0;color:var(--muted);line-height:1.55;max-width:850px}
.progress-pill{min-width:125px;padding:10px 13px;border-radius:13px;border:1px solid var(--line);background:#fff;box-shadow:0 8px 20px rgba(31,64,88,.06)}
.progress-pill span{display:block;color:var(--muted);font-size:.65rem;font-weight:800}.progress-pill strong{font-size:1.2rem}
.panel{overflow:hidden}.panel-heading{padding:20px 22px 14px;display:flex;align-items:flex-start;justify-content:space-between;gap:14px}.panel-heading.compact{padding-bottom:9px}.panel-heading h3{margin:4px 0 0;font-size:1.04rem}
.score-chip,.status-chip{padding:7px 10px;border-radius:999px;background:#eef4f7;color:#5c7080;font-size:.72rem;font-weight:900;white-space:nowrap}
.practice-layout{display:grid;grid-template-columns:minmax(340px,.72fr) minmax(0,1.28fr);gap:20px}
.stage-guide{padding:0 18px 18px;display:grid;gap:8px}
.stage-guide-card{display:grid;grid-template-columns:64px 1fr;gap:12px;align-items:center;padding:10px;border:1px solid #e6edf2;border-radius:13px;background:#fbfdfe}
.stage-guide-card strong{font-size:.82rem}.stage-guide-card p{margin:2px 0 0;color:var(--muted);font-size:.7rem;line-height:1.4}
.mini-cell{width:56px;height:56px;border-radius:50%;background:#e7d8ec;border:3px solid #c4adc9;position:relative;overflow:hidden;box-shadow:inset 0 0 12px rgba(91,64,101,.12)}
.mini-nucleus{position:absolute;width:26px;height:26px;border-radius:50%;background:#a987b2;left:12px;top:12px;box-shadow:inset 0 0 0 3px rgba(91,56,103,.18)}
.prophase-mini span,.metaphase-mini span,.anaphase-mini span{position:absolute;width:5px;height:23px;border-radius:4px;background:#74537e}
.prophase-mini span:nth-child(1){left:18px;top:12px;transform:rotate(35deg)}.prophase-mini span:nth-child(2){left:31px;top:20px;transform:rotate(-31deg)}.prophase-mini span:nth-child(3){left:21px;top:29px;transform:rotate(75deg)}
.metaphase-mini span{top:16px}.metaphase-mini span:nth-child(1){left:21px}.metaphase-mini span:nth-child(2){left:27px}.metaphase-mini span:nth-child(3){left:33px}
.anaphase-mini span{height:17px;top:19px}.anaphase-mini span:nth-child(1){left:13px;transform:rotate(-32deg)}.anaphase-mini span:nth-child(2){left:20px;transform:rotate(32deg)}.anaphase-mini span:nth-child(3){right:20px;transform:rotate(-32deg)}.anaphase-mini span:nth-child(4){right:13px;transform:rotate(32deg)}
.telophase-mini .left{left:5px;top:15px;width:22px;height:22px}.telophase-mini .right{left:29px;top:15px;width:22px;height:22px}
.practice-microscope,.field-shell{position:relative;overflow:hidden;background:#d9cfe3;border-top:1px solid #e4eaf0;border-bottom:1px solid #e4eaf0}
.practice-microscope{height:390px}.practice-microscope canvas,.field-shell canvas{width:100%;height:100%;display:block;position:relative;z-index:1}
.microscope-vignette{position:absolute;inset:0;z-index:3;pointer-events:none;background:radial-gradient(circle at center,transparent 56%,rgba(24,39,51,.12) 69%,rgba(16,28,37,.88) 71%)}
.choice-grid{padding:15px 18px 8px;display:grid;grid-template-columns:repeat(5,1fr);gap:8px}
.choice-grid button,.claim-choices button{border:1px solid #d9e4eb;background:#fff;padding:10px;border-radius:10px;cursor:pointer;font-weight:800;font-size:.76rem}
.choice-grid button:hover,.claim-choices button:hover{background:#f3f8fb}.choice-grid button.selected,.claim-choices button.selected{background:#eaf3ff;border-color:#9ec8f7;color:var(--blue-dark)}.choice-grid button:disabled{opacity:.6;cursor:not-allowed}
.feedback{margin:10px 18px;padding:11px 13px;border-radius:11px;font-size:.78rem;line-height:1.45;border:1px solid #dfe8ee;background:#f6f9fb;color:#5d7282}
.feedback.correct{background:var(--green-soft);border-color:#c9e8d6;color:#276444}.feedback.incorrect{background:#fff0ef;border-color:#f0cdca;color:#8a4844}.feedback.notice{background:var(--amber-soft);border-color:#efdda5;color:#745b1e}
.panel-actions{padding:2px 18px 18px;display:flex;justify-content:flex-end;gap:8px}.panel-actions.stacked{display:grid}
.primary-btn,.secondary-btn{border:0;border-radius:11px;cursor:pointer;font-weight:900;padding:11px 14px}
.primary-btn{color:#fff;background:linear-gradient(135deg,var(--blue),#4a9bf0);box-shadow:0 8px 18px rgba(47,128,237,.22)}
.secondary-btn{color:var(--blue-dark);background:#edf5ff;border:1px solid #d9eaff}.primary-btn:disabled,.secondary-btn:disabled{opacity:.48;cursor:not-allowed;box-shadow:none}
.full-width{width:calc(100% - 36px);margin:3px 18px 18px}.danger-lite{color:#96524e;background:#fff2f1;border-color:#f0d6d3}
.sample-selector{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-bottom:12px}
.sample-tab{border:1px solid var(--line);background:#fff;border-radius:13px;padding:11px 14px;cursor:pointer;text-align:left;font-weight:900;box-shadow:0 6px 16px rgba(31,64,88,.05)}
.sample-tab small{display:block;margin-top:3px;font-size:.64rem;color:var(--muted);font-weight:700}.sample-tab.active{background:#edf5ff;border-color:#bcd9f8;color:var(--blue-dark)}
.sample-tab.complete{border-color:#bfe4cf;background:#f2fbf6}.sample-tab.complete small{color:var(--green)}
.microscope-layout{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(300px,.68fr);gap:20px}.field-shell{height:530px}
.field-hint{padding:11px 18px 16px;color:var(--muted);font-size:.75rem;line-height:1.45}.field-hint strong{color:#496278}
.cell-inspector{height:245px;margin:0 18px 12px;border:1px solid var(--line);border-radius:14px;overflow:hidden;background:#e0d4e7;position:relative}
.cell-inspector canvas{width:100%;height:100%;display:block}.inspector-placeholder{position:absolute;inset:0;display:grid;place-items:center;text-align:center;padding:20px;color:#7c8d9a;font-size:.76rem;z-index:2;background:#f8fbfd}.cell-inspector:not(.empty) .inspector-placeholder{display:none}
.binary-choices{display:grid;grid-template-columns:1fr 1fr;gap:8px;padding:0 18px 12px}.classification-btn{border:1px solid #dbe5eb;background:#fff;border-radius:12px;cursor:pointer;padding:10px;text-align:left}
.classification-btn strong{display:block;font-size:.78rem}.classification-btn span{display:block;color:var(--muted);font-size:.64rem;margin-top:2px}.classification-btn.selected{border-color:#94c4f8;background:#edf5ff}.classification-btn:disabled{opacity:.45;cursor:not-allowed}
.classification-summary{margin:0 18px 10px;display:grid;grid-template-columns:repeat(3,1fr);gap:7px}.classification-summary div{padding:9px;border-radius:10px;background:#f6f9fb;border:1px solid #e3ebf0}.classification-summary span{display:block;color:var(--muted);font-size:.61rem}.classification-summary strong{font-size:1.05rem}
.formula-card{margin-bottom:16px;padding:18px 22px;display:flex;justify-content:space-between;align-items:center;gap:18px;background:linear-gradient(135deg,#f3f8ff,#f9f7ff)}
.formula-card strong{display:block;font-size:1.15rem;margin-top:4px}.formula-example{color:var(--muted);font-size:.76rem}
.table-wrap{overflow:auto;padding:0 18px 18px}table{width:100%;border-collapse:collapse}th{color:#6b7d8c;font-size:.66rem;text-transform:uppercase;letter-spacing:.05em;text-align:left;padding:10px;border-bottom:1px solid var(--line);white-space:nowrap}td{padding:11px 10px;border-bottom:1px solid #edf2f5;font-size:.78rem}
.analysis-table input{width:96px;border:1px solid #cad9e3;border-radius:9px;padding:7px 8px}.check-index-btn{border:0;background:#edf5ff;color:var(--blue-dark);font-weight:900;border-radius:8px;padding:7px 9px;cursor:pointer}.index-ok{color:var(--green);font-weight:900}.index-fix{color:#aa594f;font-weight:800}
.context-panel{margin-top:16px;padding:18px 20px;display:grid;grid-template-columns:auto 1fr;gap:14px;background:#fff9e9;border-color:#efdda4}.context-icon{width:36px;height:36px;border-radius:50%;display:grid;place-items:center;background:#f1c96b;color:#694c11;font-weight:900}.context-panel h3{margin:3px 0 5px}.context-panel p:last-child{margin:0;color:#66592f;line-height:1.5;font-size:.84rem}.hidden{display:none!important}.section-actions{display:flex;justify-content:flex-end;margin-top:16px}
.test-layout{display:grid;grid-template-columns:minmax(300px,.7fr) minmax(0,1.3fr);gap:20px}.test-list{padding:0 14px 10px;display:grid;gap:8px}
.test-btn{border:1px solid #dde7ed;background:#fff;border-radius:12px;padding:10px;cursor:pointer;display:grid;grid-template-columns:auto 1fr auto;gap:9px;align-items:center;text-align:left}.test-btn:hover{background:#f8fbfd}.test-btn.selected{background:#edf5ff;border-color:#abd0f8}.test-btn.completed{background:#f1faf5;border-color:#c7e8d5}
.test-number{width:28px;height:28px;border-radius:50%;background:#edf2f5;color:#607586;display:grid;place-items:center;font-size:.7rem;font-weight:900}.test-btn strong{display:block;font-size:.77rem}.test-btn small{display:block;margin-top:2px;color:var(--muted);font-size:.62rem;line-height:1.35}.test-state{font-size:.64rem;font-weight:900;color:var(--blue-dark)}.test-btn.completed .test-state{color:var(--green)}
.test-explainer{margin:4px 18px 10px;padding:12px;background:#f6f9fb;border-radius:11px}.test-explainer strong{font-size:.78rem}.test-explainer p{margin:4px 0 0;color:var(--muted);font-size:.68rem;line-height:1.42}
.culture-grid{padding:0 18px 14px;display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.culture-card{min-width:0}.culture-label{display:flex;justify-content:space-between;gap:6px;align-items:baseline;margin-bottom:7px}.culture-label strong{font-size:.76rem}.culture-label span{font-size:.63rem;color:var(--muted);text-align:right}
.culture-dish{aspect-ratio:1/1;border-radius:50%;position:relative;overflow:hidden;background:radial-gradient(circle at 45% 40%,rgba(255,255,255,.8),rgba(230,215,237,.95) 68%,rgba(190,168,200,.95) 69%,rgba(235,227,240,.95) 74%);border:6px solid #d7e1e8;box-shadow:inset 0 0 20px rgba(80,54,89,.13),0 7px 16px rgba(31,64,88,.07)}
.culture-cell{position:absolute;border-radius:50%;background:#b98ac2;border:1px solid rgba(95,64,104,.25);box-shadow:inset 0 0 0 2px rgba(255,255,255,.16);transform:scale(.2);opacity:0;transition:transform .55s ease,opacity .55s ease}.culture-cell.visible{transform:scale(1);opacity:1}.culture-cell.dividing{background:#8f6fa1}.culture-cell.paused{background:#a8b6c4}.culture-cell.dysregulated{background:#865a9d;box-shadow:0 0 0 2px rgba(134,90,157,.14)}
.results-panel{margin-top:20px}.empty-row td{text-align:center;color:#8797a4;padding:26px 12px}
.evidence-board{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-bottom:20px}.evidence-card{background:#fff;border:1px solid var(--line);border-radius:16px;padding:17px;box-shadow:0 10px 24px rgba(31,64,88,.07)}.evidence-card h3{margin:0 0 9px;font-size:1rem}.evidence-line{display:flex;justify-content:space-between;gap:12px;padding:7px 0;border-top:1px solid #edf2f5;font-size:.72rem}.evidence-line:first-of-type{border-top:0}.evidence-line span{color:var(--muted)}.evidence-line strong{text-align:right}.evidence-card .context-tag{display:inline-block;margin-top:10px;padding:6px 8px;border-radius:999px;background:#f5f7f9;color:#617482;font-size:.63rem;font-weight:800}
.claim-choices{display:grid;grid-template-columns:repeat(3,1fr);gap:9px;padding:0 18px 6px}.cer-grid{padding:5px 18px 18px;display:grid;grid-template-columns:1fr 1fr;gap:12px}.cer-grid label:first-child{grid-column:1/-1}.cer-grid label span{display:block;margin-bottom:6px;font-size:.72rem;font-weight:900;color:#526a7c}.cer-grid textarea{width:100%;resize:vertical;border:1px solid #cedce5;border-radius:11px;padding:11px;color:var(--ink);line-height:1.45;background:#fbfdfe}
.final-actions{padding:0 18px 20px;display:flex;flex-wrap:wrap;gap:8px}.limitation-panel{margin-top:18px;padding:17px 20px;display:grid;grid-template-columns:auto 1fr;gap:12px;background:#f7fafc}.limitation-icon{width:32px;height:32px;border-radius:50%;display:grid;place-items:center;background:#e8eff4;color:#5b7182;font-weight:900}.limitation-panel h3{margin:1px 0 4px;font-size:.88rem}.limitation-panel p{margin:0;color:var(--muted);font-size:.75rem;line-height:1.5}
.site-footer{margin-bottom:28px;padding:18px 3px;display:flex;justify-content:space-between;gap:18px;color:#718493;font-size:.75rem}
@media (max-width:1000px){.hero,.practice-layout,.microscope-layout,.test-layout{grid-template-columns:1fr}.reference-panel{order:2}.field-shell{height:480px}}
@media (max-width:800px){.step-nav{grid-template-columns:1fr}.step-tab{grid-template-columns:auto 1fr auto}.step-tab small{grid-column:3;grid-row:1/3;align-self:center}.culture-grid,.evidence-board,.sample-selector{grid-template-columns:1fr}}
@media (max-width:650px){.site-header,.section-heading,.site-footer,.formula-card{flex-direction:column;align-items:flex-start}.hero-copy{padding:24px}.choice-grid{grid-template-columns:1fr 1fr}.binary-choices{grid-template-columns:1fr}.cer-grid{grid-template-columns:1fr}.cer-grid label:first-child{grid-column:auto}.field-shell{height:400px}.site-header,.page-shell,.site-footer{width:min(100% - 20px,1240px)}}