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button[aria-pressed=true]{background:var(--ink);color:var(--paper);border-color:var(--ink)}.tick{color:var(--pen);font-family:var(--serif);margin-left:6px;font-style:italic;font-weight:600}.ring{width:82px;height:64px;color:var(--pen);font-family:var(--serif);place-items:center;font-size:1.7rem;font-style:italic;font-weight:600;line-height:1;display:grid;position:absolute;top:26px;right:26px}.ring svg{width:100%;height:100%;position:absolute;inset:0;overflow:visible}.ring small{font-size:.7rem;font-style:normal;font-family:var(--ui);text-align:center;margin-top:2px;font-weight:500;display:block}.ring-big{width:150px;height:112px;color:var(--pen);font-family:var(--serif);place-items:center;font-size:2.4rem;font-style:italic;font-weight:600;display:grid;position:relative}.ring-big svg{width:100%;height:100%;position:absolute;inset:0;overflow:visible}@media (width<=700px){.ring{top:12px;right:8px;transform:scale(.85)}.sheet-head{padding-right:76px}}.sheet-actions{font-family:var(--ui);flex-wrap:wrap;justify-content:flex-end;gap:10px;margin-top:8px;display:flex}.tips{gap:8px;margin:0;padding-left:1.2em;display:grid}.tips li::marker{color:var(--brand)}.hello{gap:4px;display:grid}.hello h1{font-size:1.9rem}.stat-row{border:1px solid var(--line);border-radius:var(--r-lg);background:var(--paper);grid-template-columns:repeat(3,minmax(0,1fr));gap:0;display:grid;overflow:hidden}.stat{border-right:1px solid var(--line);padding:18px 20px}.stat:last-child{border-right:0}.stat b{font-variant-numeric:tabular-nums;font-size:1.7rem;font-weight:650;display:block}.stat span{color:var(--muted);font-size:.85rem}@media (width<=600px){.stat{padding:14px}.stat b{font-size:1.35rem}}.bars{gap:10px;display:grid}.bar{grid-template-columns:minmax(0,13em) minmax(0,1fr) 3.5em;align-items:center;gap:12px;font-size:.9rem;display:grid}.bar .track{background:var(--desk);border:1px solid var(--line);border-radius:999px;height:10px;overflow:hidden}.bar .fill{background:var(--brand);border-radius:999px;height:100%}.bar .fill.low{background:var(--pen)}.bar .pct{text-align:right;font-variant-numeric:tabular-nums;color:var(--muted)}@media (width<=600px){.bar{grid-template-columns:minmax(0,9em) minmax(0,1fr) 3em;gap:8px}}.next{color:inherit;grid-template-columns:auto 1fr auto;align-items:center;gap:16px;text-decoration:none;display:grid}.next .ic{background:var(--brand-soft);width:48px;height:48px;color:var(--brand);border-radius:12px;place-items:center;display:grid}.list{border:1px solid var(--line);border-radius:var(--r-lg);background:var(--paper);display:grid;overflow:hidden}.list>a,.list>button,.list>div.li,.list .li-btn,.list .li{text-align:left;border:0;border-bottom:1px solid var(--line);color:inherit;cursor:pointer;background:0 0;grid-template-columns:2.4em minmax(0,1fr) 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span{text-align:center;color:var(--muted);font-size:.72rem;position:absolute;top:-18px;left:0;right:0}.vocab-list{gap:0;display:grid}.vocab-list>div{border-bottom:1px solid var(--line);grid-template-columns:minmax(0,14em) minmax(0,1fr);gap:16px;padding:12px 4px;display:grid}.vocab-list .w{font-family:var(--serif);font-size:1.08rem;font-weight:600}.vocab-list .ex{font-family:var(--serif);color:var(--muted);font-size:.95rem;font-style:italic}@media (width<=600px){.vocab-list>div{grid-template-columns:1fr;gap:2px}}.toc-grid{columns:2;column-gap:32px}.toc-grid>div{break-inside:avoid;margin-bottom:16px}@media (width<=700px){.toc-grid{columns:1}}details.acc{border-bottom:1px solid var(--line)}details.acc summary{cursor:pointer;justify-content:space-between;gap:12px;padding:14px 4px;font-weight:600;list-style:none;display:flex}details.acc summary::-webkit-details-marker{display:none}details.acc[open] summary svg{transform:rotate(180deg)}details.acc>div{padding:0 4px 16px}.contact{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;display:flex}.contact-who{gap:2px;min-width:0;display:grid}.contact-who b{font-size:1.1rem}.contact-phone{font-variant-numeric:tabular-nums;color:var(--brand);font-size:1.05rem;font-weight:600}.contact.compact{border:1px solid var(--line);border-radius:var(--r);background:var(--desk);padding:14px 16px}.contact.compact .contact-who b{font-size:1rem}.why{border-top:1px dashed var(--line-strong);color:var(--ink);gap:4px;margin-top:8px;padding-top:8px;display:grid}.why i{font-family:var(--serif);font-size:1.02rem}.correction.right .why{color:var(--muted)}.g-ex{border-left:2px solid var(--brand-line);gap:10px;padding-left:14px;display:grid}.g-ex .en{font-family:var(--serif);font-size:1.08rem;font-style:italic}.g-ex .vi{color:var(--muted);font-size:.9rem}.btn.check-btn{min-height:32px;font-size:.82rem;font-weight:500;font-family:var(--ui);color:var(--brand);border-color:var(--brand-line);background:0 0;margin-top:6px;padding:4px 12px}.btn.check-btn:hover{background:var(--brand-soft)}.instant-toggle{cursor:pointer;align-items:center;gap:8px;min-height:36px;font-size:.88rem;font-weight:500;display:inline-flex}.instant-toggle input{width:18px;height:18px;accent-color:var(--brand)}.write-card{gap:10px;display:grid}.write-card .m{font-size:1.35rem;font-weight:600}.write-card .ex{font-family:var(--serif);color:var(--muted);font-style:italic}.hint-letters{font-family:var(--serif);letter-spacing:.12em;color:var(--muted);font-size:1.05rem}.write-in{font-family:var(--serif);color:var(--brand);font-size:1.25rem;font-style:italic}.write-in.ok{border-color:var(--ok);color:var(--ok)}.write-in.bad{border-color:var(--pen);color:var(--pen);text-decoration:line-through}