.study-hub{max-width:860px;color:var(--text-main);margin:0 auto;padding:24px 16px 96px}.study-hub.is-review{max-width:720px;padding-bottom:0}.study-hub-head{flex-wrap:wrap;justify-content:space-between;align-items:flex-end;gap:12px;margin-bottom:16px;display:flex}.study-hub-head h1{margin:0;font-size:1.5rem}.study-hub-sub{color:var(--text-muted);margin:4px 0 0;font-size:.9rem}.study-hub-actions,.study-deck-actions{flex-wrap:wrap;gap:6px;display:flex}.study-hub-actions .material-symbols-outlined{vertical-align:-4px;margin-right:4px;font-size:18px}.study-empty{text-align:center;color:var(--text-muted);padding:48px 16px}.study-empty .material-symbols-outlined{font-size:40px}.study-hint{color:var(--text-muted);font-size:.82rem;line-height:1.5}.study-foot{margin-top:16px}.study-decks{gap:10px;margin:0;padding:0;list-style:none;display:grid}.study-deck{border:1px solid var(--border);background:var(--bg-card);border-radius:12px;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:10px;padding:12px 14px;display:flex}.study-deck-main{gap:6px;min-width:0;display:grid}.study-deck-name{overflow-wrap:anywhere}.study-deck-counts{flex-wrap:wrap;gap:6px;display:flex}.study-count{background:var(--bg-muted);color:var(--text-muted);border-radius:999px;padding:2px 8px;font-size:.78rem}.study-count.is-due.is-on{background:color-mix(in srgb, #dc2626 14%, var(--bg-muted));color:var(--text-main)}.study-count.is-new.is-on{background:color-mix(in srgb, #2563eb 14%, var(--bg-muted));color:var(--text-main)}.study-review{flex-direction:column;min-height:calc(100dvh - 120px);display:flex}.study-review-head{align-items:center;gap:8px;margin-bottom:12px;display:flex}.study-review-title{text-overflow:ellipsis;white-space:nowrap;flex:1;min-width:0;overflow:hidden}.study-review-left{color:var(--text-muted);font-size:.85rem}.study-icon-btn{color:var(--text-main);cursor:pointer;background:0 0;border:0;border-radius:8px;width:36px;height:36px}.study-icon-btn:hover{background:var(--bg-hover)}.study-card{border:1px solid var(--border);background:var(--bg-card);text-align:center;cursor:pointer;overflow-wrap:anywhere;border-radius:16px;outline:none;flex:1;padding:28px 20px;font-size:1.15rem;line-height:1.6}.study-card:focus-visible{box-shadow:0 0 0 2px var(--accent)}.study-card hr{border:0;border-top:1px dashed var(--border);margin:20px 0}.study-card-extra{color:var(--text-muted);margin-top:16px;font-size:.95rem}.study-card-source{color:var(--text-muted);margin:18px 0 0;font-size:.78rem}.study-answer-bar{padding:12px 0 calc(12px + env(safe-area-inset-bottom));background:var(--bg-main,var(--bg-card));position:sticky;bottom:0}.study-show{background:var(--accent);color:#fff;width:100%;min-height:52px;font:inherit;cursor:pointer;border:0;border-radius:12px;font-weight:650}.study-grades{grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;display:grid}.study-grade{border:1px solid var(--border);background:var(--bg-muted);min-height:56px;color:var(--text-main);font:inherit;cursor:pointer;border-radius:12px;place-content:center;gap:2px;display:grid}.study-grade-label{font-size:.92rem;font-weight:650}.study-grade-hint{color:var(--text-muted);font-size:.72rem}.study-grade.is-again{background:color-mix(in srgb, #dc2626 12%, var(--bg-muted))}.study-grade.is-good{background:color-mix(in srgb, #16a34a 12%, var(--bg-muted))}.study-grade.is-easy{background:color-mix(in srgb, #2563eb 12%, var(--bg-muted))}.study-done{text-align:center;padding:64px 16px}.study-done .material-symbols-outlined{color:var(--accent);font-size:48px}@media (max-width:520px){.study-deck-actions{width:100%}.study-card{padding:22px 14px;font-size:1.05rem}}.right-quiz-cite{background:var(--bg-muted);color:var(--text-muted);border-radius:10px;align-items:flex-start;gap:6px;padding:.4rem .55rem;font-size:.78rem;line-height:1.45;text-decoration:none;display:flex}.right-quiz-cite:hover{color:var(--text-main);background:var(--bg-hover)}.right-quiz-cite .material-symbols-outlined{font-size:16px}.right-quiz-cite em{color:var(--text-main);font-style:normal;display:block}