header{padding:40px 0 8px;text-align:center}
h1{font-family:var(--font-display);font-weight:700;font-size:clamp(22px,3.4vw,32px);letter-spacing:-.01em;line-height:1.2;margin-bottom:12px}
.sub{color:var(--ink-soft);font-size:16px;max-width:600px;margin:0 auto}

.modes{display:flex;gap:8px;justify-content:center;margin-top:22px;flex-wrap:wrap}
.mode{border:2px solid var(--line);background:var(--card);border-radius:99px;padding:10px 18px;font-weight:800;font-size:14px;cursor:pointer;font-family:var(--font-body);color:var(--ink-soft);transition:all .15s}
.mode:hover{border-color:#C9D2F2}
.mode.active{border-color:var(--blue);background:var(--blue-soft);color:var(--blue-dark)}
.mode small{display:block;font-size:11.5px;font-weight:700;opacity:.75}

.grades{display:none;justify-content:center;gap:8px;margin-top:18px;flex-wrap:wrap}
body[data-mode="grade"] .grades{display:flex}
.grade{width:46px;height:46px;border:2px solid var(--line);background:var(--card);border-radius:12px;font-family:var(--font-mono);font-weight:600;font-size:15px;color:var(--ink);cursor:pointer;transition:all .15s}
.grade:hover{border-color:#C9D2F2}
.grade.active{border-color:var(--blue);background:var(--blue);color:#fff}
.grade:disabled{opacity:.35;cursor:not-allowed}
.grades-label{width:100%;text-align:center;font-size:13px;font-weight:700;color:var(--ink-soft);margin-bottom:2px}

.hint{display:inline-flex;align-items:center;gap:8px;margin-top:18px;background:var(--blue-soft);color:var(--blue-dark);font-weight:700;font-size:14px;border-radius:99px;padding:8px 18px;transition:background .2s,color .2s}
.hint.warn{background:var(--amber-soft);color:var(--amber-ink)}
.hint.done{background:var(--mint-soft);color:var(--mint-ink)}

main{flex:1;padding:30px 0 150px}
.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.subj{position:relative;background:var(--card);border:2px solid var(--line);border-radius:var(--radius);padding:20px 20px 16px;cursor:pointer;text-align:left;font-family:var(--font-body);transition:transform .15s,border-color .15s,box-shadow .15s,opacity .2s;user-select:none}
.subj:hover{transform:translateY(-2px);border-color:#C9D2F2;box-shadow:var(--shadow)}
.subj h3{font-size:16.5px;font-weight:800;line-height:1.3;margin-bottom:5px;padding-right:30px}
.subj p{font-size:12.5px;color:var(--ink-soft);font-weight:600}
body[data-mode="pair"] .subj .p-grade{display:none}
body[data-mode="single"] .subj .p-pair,body[data-mode="single"] .subj .p-grade{display:none}
body[data-mode="grade"] .subj .p-pair{display:none}
.subj .mark{position:absolute;top:14px;right:14px;width:24px;height:24px;border-radius:8px;border:2px solid var(--line);display:flex;align-items:center;justify-content:center;transition:all .15s}
.subj .mark svg{width:13px;height:13px;opacity:0}
.subj.selected{border-color:var(--blue);background:var(--blue-soft)}
.subj.selected .mark{background:var(--blue);border-color:var(--blue)}
.subj.selected .mark svg{opacity:1}
.subj.selected p{color:var(--blue-dark)}
.subj.compatible{border-color:#B9C1F5}
.subj.compatible::after{content:attr(data-badge);position:absolute;bottom:-9px;left:16px;background:var(--blue);color:#fff;font-size:10.5px;font-weight:800;letter-spacing:.03em;border-radius:99px;padding:2px 10px}
.subj.disabled{opacity:.38;cursor:not-allowed;transform:none!important;box-shadow:none!important}
.subj.disabled:hover{border-color:var(--line)}
.subj.shake{animation:shake .35s}
@keyframes shake{0%,100%{transform:translateX(0)}25%{transform:translateX(-5px)}75%{transform:translateX(5px)}}
@media (prefers-reduced-motion:reduce){.subj.shake{animation:none}}

.bar{position:fixed;left:0;right:0;bottom:0;z-index:60;background:rgba(255,255,255,.94);backdrop-filter:blur(12px);border-top:1px solid var(--line);transform:translateY(110%);transition:transform .25s ease}
.bar.show{transform:none}
.bar-inner{max-width:980px;margin:0 auto;padding:16px 24px;display:flex;align-items:center;gap:18px;flex-wrap:wrap}
.pair{display:flex;align-items:center;gap:10px;font-weight:800;font-size:16px;flex-wrap:wrap}
.pair .chip{background:var(--blue-soft);color:var(--blue-dark);border-radius:10px;padding:7px 14px;font-size:14.5px}
.pair .chip.g{background:var(--amber-soft);color:var(--amber-ink)}
.pair .plus{font-family:var(--font-mono);color:var(--ink-soft)}
.bar .btn{margin-left:auto}
.reset{background:none;border:none;font-family:var(--font-body);font-weight:700;font-size:14px;color:var(--ink-soft);cursor:pointer;text-decoration:underline;text-underline-offset:3px}
.reset:hover{color:var(--ink)}

@media(max-width:760px){
  .grid{grid-template-columns:repeat(2,1fr);gap:10px}
  .subj{padding:16px 14px 14px}
  .subj h3{font-size:14.5px}
  header{padding-top:26px}
  main{padding-bottom:190px}
  .bar-inner{gap:12px}
  .bar .btn{width:100%;margin-left:0}
  .mode{padding:9px 14px;font-size:13px}
}