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p{color:#39405d}.form{display:flex;gap:12px;flex-wrap:wrap;align-items:end}label{font-weight:650;font-size:.85rem;display:grid;gap:5px}select,input[type=search]{border:1px solid var(--line);border-radius:9px;padding:10px;background:var(--surface);color:inherit;max-width:100%}.progress{height:10px;background:#e9e7f2;border-radius:10px;overflow:hidden}.progress i{display:block;height:100%;background:var(--accent)}.qnav{display:flex;flex-wrap:wrap;gap:6px}.qnav button{width:39px;height:39px;border-radius:9px;border:1px solid var(--line);background:var(--surface);color:inherit}.qnav button.current{outline:2px solid var(--accent)}.qnav button.answered{background:#e6e0fb}.qnav button.flagged{border-color:#e89d45;border-width:3px}.term{font-size:1.7rem;font-weight:800;text-align:center;padding:35px 10px}.flip{min-height:230px;display:grid;place-items:center;text-align:center;cursor:pointer}.note{font-size:.85rem}.danger{color:var(--bad)}.mobile-only{display:none}footer{margin:30px 0;color:var(--muted);font-size:.8rem}.dark{color:#e9e9f2;background:#0d1324;--surface:#182238;--muted:#aab4ca;--line:#34405a;--accent:#aa90ff;--good:#72d7ae;--bad:#ff8998}.dark .option.selected,.dark .qnav button.answered{background:#342c57}.dark .option.correct{background:#173d35}.dark .option.wrong{background:#44232f}.dark .feedback{background:#292447}.dark .feedback p{color:#d6d0ed}.dark .btn.secondary{background:#392e64;color:#e2d9ff}@media(max-width:850px){.shell{display:block}aside{position:sticky;top:0;z-index:5;padding:8px 12px;gap:6px;box-shadow:0 4px 15px #10182a33}.brand,.sidebar-note{display:none}nav{display:flex;overflow:auto;scrollbar-width:none}nav button{white-space:nowrap;padding:9px 11px;font-size:.82rem}main{padding:22px 16px 80px}.stats{grid-template-columns:repeat(2,1fr)}.grid{grid-template-columns:1fr}.hero{display:block}.hero .btn{margin-top:8px}.card{padding:18px}.question{font-size:1.2rem}}@media(max-width:420px){.stats{gap:8px}.stat{padding:14px}.stat 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