:root{--ink:#102a43;--muted:#627d98;--line:#d9e2ec;--paper:#fff;--bg:#f4f7fb;--brand:#0f766e;--brand-dark:#115e59;--accent:#f59e0b;--danger:#b42318;--success:#067647;--shadow:0 12px 30px rgba(16,42,67,.08)}
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68px);display:grid;place-items:center;padding:24px 16px}.auth-shell+.site-footer{display:none}.auth-card{width:min(430px,100%);background:var(--paper);border:1px solid var(--line);border-radius:10px;padding:32px;box-shadow:var(--shadow)}.auth-title{margin:0 0 8px;font-size:26px}.auth-subtitle{margin:0 0 26px;color:var(--muted);font-size:14px}.field{display:grid;gap:7px;margin-bottom:17px}.field label{font-size:14px;font-weight:650}.field input,.field textarea,.field select{width:100%;border:1px solid #bcccdc;border-radius:7px;padding:12px 13px;font:inherit;color:var(--ink);background:#fff;min-height:46px}.field textarea{resize:vertical;min-height:96px}.field input:focus,.field textarea:focus,.field select:focus{outline:3px solid rgba(15,118,110,.14);border-color:var(--brand)}.btn{border:0;border-radius:7px;min-height:46px;padding:0 18px;font:inherit;font-weight:700;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;gap:8px;transition:.15s}.btn-primary{background:var(--brand);color:#fff}.btn-primary:hover{background:var(--brand-dark)}.btn-secondary{background:#e6fffb;color:#115e59}.btn-ghost{background:#eef2f6;color:var(--ink)}.btn-danger{background:#fff1f0;color:var(--danger)}.btn-block{width:100%}.auth-link{text-align:center;color:var(--muted);font-size:14px;margin:20px 0 0}.auth-link a{color:var(--brand);font-weight:700}.alert{max-width:1120px;margin:0 auto 18px;padding:12px 15px;border-radius:7px;font-size:14px}.alert.success{background:#ecfdf3;color:var(--success);border:1px solid #abefc6}.alert.error{background:#fff1f0;color:var(--danger);border:1px solid #fecdca}.hero-row{display:flex;justify-content:space-between;align-items:flex-end;gap:18px;margin-bottom:22px}.eyebrow{margin:0 0 5px;color:var(--brand);font-size:12px;font-weight:800;letter-spacing:.08em}.page-title{margin:0;font-size:30px;letter-spacing:0}.muted{color:var(--muted)}.panel{background:var(--paper);border:1px solid var(--line);border-radius:9px;box-shadow:var(--shadow);padding:24px}.grid-2{display:grid;grid-template-columns:1.05fr .95fr;gap:22px}.grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.stat-card{background:var(--paper);border:1px solid var(--line);border-radius:9px;padding:20px}.stat-label{font-size:13px;color:var(--muted)}.stat-value{font-size:32px;font-weight:800;margin-top:8px}.form-actions{display:flex;gap:10px;flex-wrap:wrap;margin-top:20px}.hint{font-size:13px;color:var(--muted);line-height:1.65}.word-preview{background:#f0fdfa;border:1px solid #99f6e4;border-radius:8px;padding:16px;margin-top:18px}.word-preview strong{font-size:21px}.study-setup{max-width:720px;margin:16px auto}.choice-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.choice{border:1px solid var(--line);border-radius:8px;padding:16px;cursor:pointer;display:block}.choice:has(input:checked){border-color:var(--brand);background:#f0fdfa}.choice input{accent-color:var(--brand);margin-right:8px}.study-card{max-width:760px;margin:10px auto}.study-meta{display:flex;justify-content:space-between;gap:12px;color:var(--muted);font-size:13px;margin-bottom:20px}.mask-word{font-size:clamp(28px,7vw,48px);letter-spacing:.14em;text-align:center;font-weight:800;margin:24px 0 28px;word-break:break-all}.meaning-box{display:grid;gap:10px;margin-bottom:22px}.meaning{border-left:3px solid var(--brand);padding:10px 13px;background:#f8fafc}.meaning b{display:block;font-size:12px;color:var(--muted);margin-bottom:4px}.audio-btn{min-height:40px}.feedback{padding:14px;border-radius:8px;margin:0 0 18px;font-weight:700}.feedback.correct{background:#ecfdf3;color:var(--success)}.feedback.wrong{background:#fff1f0;color:var(--danger)}.answer-reveal{border:1px solid #fecdca;border-radius:8px;padding:14px;margin-bottom:18px;background:#fffafa}.answer-reveal .answer{font-size:25px;font-weight:800;margin:4px 0 12px}.table-wrap{overflow-x:auto}.data-table{width:100%;border-collapse:collapse;font-size:14px}.data-table th,.data-table td{text-align:left;padding:13px 10px;border-bottom:1px solid var(--line);white-space:nowrap}.data-table th{color:var(--muted);font-weight:700}.rank{font-weight:800;color:var(--accent)}.empty{padding:34px 16px;text-align:center;color:var(--muted)}.section-title{font-size:18px;margin:0 0 16px}.small{font-size:12px;color:var(--muted)}
@media (max-width:700px){.nav-wrap{align-items:flex-start;flex-direction:column;padding:12px 16px}.main-nav{width:100%;justify-content:flex-start;gap:12px 16px;font-size:13px}.page-shell{padding:22px 14px 42px}.hero-row{align-items:flex-start;flex-direction:column}.page-title{font-size:26px}.grid-2,.grid-3{grid-template-columns:1fr;gap:14px}.panel{padding:18px}.auth-card{padding:25px 20px}.choice-grid{grid-template-columns:1fr}.mask-word{letter-spacing:.1em}.form-actions .btn{width:100%}.study-meta{font-size:12px}.data-table th,.data-table td{padding:11px 8px}}