:root{
 --primary:#126c72;--primary2:#18858c;--charcoal:#172126;--bg:#f6f8f9;--surface:#fff;
 --border:#e5eaec;--muted:#718087;--ink:#172126;--danger:#a6413b;--warn:#9a6a15;--ok:#2f7554;
 --radius:20px;--shadow:0 12px 34px rgba(23,33,38,.08);
 --font:"Segoe UI Variable Text","Segoe UI",system-ui,-apple-system,BlinkMacSystemFont,Arial,sans-serif;
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:var(--font);background:var(--bg);color:var(--ink);-webkit-font-smoothing:antialiased}
button,input,textarea,select{font:inherit}button{cursor:pointer}.app{min-height:100vh}.topbar{height:72px;background:var(--charcoal);color:#fff;display:flex;align-items:center;position:sticky;top:0;z-index:50;border-bottom:1px solid #27343a}.topbar__in{width:min(1320px,calc(100% - 32px));margin:0 auto;display:flex;align-items:center;gap:18px}.brand{display:flex;align-items:center;gap:12px;font-weight:900}.brand__mark{width:38px;height:38px;border-radius:11px;display:grid;place-items:center;background:#fff;color:var(--primary);font-weight:950}.brand small{display:block;color:#91a2a8;font-weight:600;font-size:10px;letter-spacing:.08em;text-transform:uppercase}.search{margin-left:auto;display:flex;align-items:center;gap:8px}.search input{width:280px;height:42px;border:1px solid #34444b;border-radius:11px;background:#202c31;color:#fff;padding:0 13px;outline:none}.search input:focus{border-color:#54c6cc}.shell{width:min(1320px,calc(100% - 32px));margin:0 auto;display:grid;grid-template-columns:218px minmax(0,1fr);gap:26px;padding:26px 0 48px}.sidebar{position:sticky;top:98px;height:max-content}.nav{display:grid;gap:7px}.nav button{min-height:45px;border:0;border-radius:12px;padding:0 13px;text-align:left;background:transparent;color:#516168;font-weight:760}.nav button:hover,.nav button.active{background:#fff;color:var(--primary);box-shadow:0 5px 20px rgba(23,33,38,.05)}.nav small{display:block;padding:16px 13px 5px;color:#95a1a6;font-size:10px;letter-spacing:.12em;text-transform:uppercase;font-weight:900}.main{min-width:0}.hero{padding:30px;border-radius:26px;background:linear-gradient(135deg,#172126,#1f4447);color:#fff;box-shadow:var(--shadow);display:grid;grid-template-columns:1.1fr .9fr;gap:24px}.hero h1{font-size:clamp(32px,5vw,52px);line-height:1.02;letter-spacing:-.045em;margin:8px 0 12px}.hero p{color:#d2dddf;line-height:1.65}.eyebrow{font-size:11px;letter-spacing:.14em;text-transform:uppercase;font-weight:900;color:#7ce0e5}.hero__side{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.hero-stat{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.11);border-radius:16px;padding:16px}.hero-stat b{display:block;font-size:24px}.hero-stat span{color:#b6c6ca;font-size:11px}.actions{display:flex;flex-wrap:wrap;gap:9px;margin-top:18px}.btn{min-height:44px;padding:0 15px;border-radius:11px;border:1px solid transparent;font-weight:850}.btn--primary{background:#fff;color:var(--primary)}.btn--teal{background:var(--primary);color:#fff}.btn--ghost{background:transparent;border-color:#ccd7da;color:var(--ink)}.btn--darkghost{background:transparent;border-color:#4b5e65;color:#fff}.btn--danger{background:#fff0ef;color:var(--danger);border-color:#f1d3d0}.section{margin-top:26px}.section-head{display:flex;justify-content:space-between;align-items:end;gap:18px;margin-bottom:14px}.section-head h2{margin:0;font-size:24px;letter-spacing:-.025em}.section-head p{margin:4px 0 0;color:var(--muted);font-size:13px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}.subject{background:#fff;border:1px solid var(--border);border-radius:18px;padding:18px;box-shadow:0 4px 18px rgba(23,33,38,.035);transition:.18s}.subject:hover{transform:translateY(-2px);box-shadow:var(--shadow)}.subject__top{display:flex;align-items:center;justify-content:space-between;gap:10px}.subject__icon{width:44px;height:44px;border-radius:13px;color:#fff;display:grid;place-items:center;font-weight:950;font-size:12px}.subject h3{margin:16px 0 7px;font-size:18px}.subject p{margin:0;color:var(--muted);font-size:12px;line-height:1.55}.progress{height:7px;background:#edf1f2;border-radius:999px;overflow:hidden;margin-top:15px}.progress i{display:block;height:100%;background:var(--primary);border-radius:999px}.subject__meta{display:flex;justify-content:space-between;margin-top:8px;font-size:10px;color:#8b999e}.panel{background:#fff;border:1px solid var(--border);border-radius:20px;padding:20px;box-shadow:0 5px 22px rgba(23,33,38,.04)}.topic-list{display:grid;gap:10px}.topic{display:grid;grid-template-columns:1fr auto;gap:12px;align-items:center;padding:15px;border:1px solid var(--border);border-radius:14px}.topic h4{margin:0 0 4px}.topic p{margin:0;color:var(--muted);font-size:12px}.pill{display:inline-flex;min-height:29px;align-items:center;padding:0 9px;border-radius:999px;background:#edf6f6;color:var(--primary);font-size:10px;font-weight:850}.study-grid{display:grid;grid-template-columns:1fr 340px;gap:16px}.flash-wrap{perspective:1000px}.flash{min-height:390px;position:relative;transform-style:preserve-3d;transition:transform .45s}.flash.flipped{transform:rotateY(180deg)}.face{position:absolute;inset:0;backface-visibility:hidden;background:#fff;border:1px solid var(--border);border-radius:24px;padding:28px;box-shadow:var(--shadow);display:flex;flex-direction:column;justify-content:center}.back{transform:rotateY(180deg);background:#172126;color:#fff}.face small{color:var(--primary);font-weight:900;letter-spacing:.1em;text-transform:uppercase}.back small{color:#77d7dc}.face h2{font-size:30px;line-height:1.15;letter-spacing:-.035em}.face p{font-size:17px;line-height:1.7}.card-controls{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-top:12px}.rating{min-height:44px;border-radius:11px;border:1px solid var(--border);font-weight:850}.wrong{background:#fff1f0;color:#963b36}.unsure{background:#fff8e8;color:#8a651a}.known{background:#eef8f3;color:#2f7554}.sidebox{display:grid;gap:12px}.metric{padding:16px;background:#fff;border:1px solid var(--border);border-radius:16px}.metric b{font-size:22px}.metric span{display:block;color:var(--muted);font-size:11px}.quiz{display:grid;gap:12px}.question{background:#fff;border:1px solid var(--border);border-radius:20px;padding:22px}.question h3{margin:5px 0 16px}.options{display:grid;gap:8px}.option{min-height:48px;text-align:left;padding:10px 13px;border:1px solid var(--border);border-radius:12px;background:#fff;color:var(--ink)}.option:hover{border-color:#95bfc2}.option.correct{background:#ecf8f2;border-color:#94ccb0}.option.wrong{background:#fff0ef;border-color:#e2aaa6}.feedback{margin-top:12px;padding:12px;border-radius:11px;background:#f3f6f7;color:#4e5c62;font-size:12px}.exam-head{display:flex;justify-content:space-between;gap:12px;align-items:center}.exam-score{font-size:32px;font-weight:950;color:var(--primary)}.errors{display:grid;gap:10px}.error-row{padding:15px;border:1px solid #f0d4d2;border-radius:14px;background:#fff9f8}.week{display:grid;grid-template-columns:repeat(7,1fr);gap:9px}.day{background:#fff;border:1px solid var(--border);border-radius:15px;padding:14px}.day b{font-size:12px}.day ul{padding-left:16px;margin:10px 0 0;color:#617077;font-size:11px}.notearea{width:100%;min-height:180px;border:1px solid var(--border);border-radius:15px;padding:14px;resize:vertical;outline:none}.notearea:focus{border-color:#8cbfc2}.empty{padding:30px;border:1px dashed #cbd5d8;border-radius:18px;text-align:center;color:var(--muted);background:#fff}.toolbar{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-bottom:13px}.toolbar select,.toolbar input{min-height:42px;border:1px solid var(--border);border-radius:10px;background:#fff;padding:0 11px}.toast{position:fixed;right:18px;bottom:18px;z-index:80;padding:12px 15px;background:#172126;color:#fff;border-radius:12px;box-shadow:var(--shadow);font-size:12px}.footer-note{margin-top:34px;color:#88969b;font-size:10px;line-height:1.6}.mobile-nav{display:none}
@media(max-width:1050px){.shell{grid-template-columns:1fr}.sidebar{display:none}.grid{grid-template-columns:repeat(2,1fr)}.week{grid-template-columns:repeat(4,1fr)}.hero{grid-template-columns:1fr}.study-grid{grid-template-columns:1fr}.mobile-nav{display:grid;position:fixed;left:0;right:0;bottom:0;z-index:70;grid-template-columns:repeat(5,1fr);background:#fff;border-top:1px solid var(--border);padding:6px 5px calc(6px + env(safe-area-inset-bottom))}.mobile-nav button{min-height:48px;border:0;background:transparent;color:#66757b;font-size:10px;font-weight:850}.mobile-nav button.active{color:var(--primary)}body{padding-bottom:62px}}
@media(max-width:680px){.topbar{height:64px}.topbar__in{width:calc(100% - 24px)}.search input{width:150px}.shell{width:calc(100% - 22px);padding-top:14px}.hero{padding:21px;border-radius:20px}.hero h1{font-size:34px}.hero__side{grid-template-columns:1fr 1fr}.grid{grid-template-columns:1fr}.week{grid-template-columns:1fr 1fr}.section-head{display:block}.flash{min-height:420px}.face{padding:20px}.face h2{font-size:25px}.card-controls{grid-template-columns:1fr}.exam-head{align-items:flex-start;flex-direction:column}}

.sek-note{border-left:4px solid var(--primary)}

.session-task{min-height:380px}.workedsteps{padding-left:22px;color:#5f6d73;line-height:1.8}.workedsteps li{margin:8px 0}.errorclass{margin-top:12px;padding-top:12px;border-top:1px solid var(--border)}.session-task label{display:block;margin:12px 0;color:#65747a}.session-task select{min-height:40px;border:1px solid var(--border);border-radius:9px;padding:0 10px;background:#fff}