@charset "UTF-8";
:root { --paper:#f7f6f0; --white:#fffefa; --ink:#193e39; --muted:#626e65; --line:#dddfd4; --green:#e4ebe0; --accent:#a4432e; --review:#fff0d9; font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif; color:var(--ink); background:var(--paper); font-synthesis:none; scroll-padding-top:calc(var(--header-height, 89px) + 16px); }
* { box-sizing:border-box; }
body { margin:0; }
button,input,textarea,select { font:inherit; }
a { color:inherit; }
button { cursor:pointer; }
button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible { outline:2px solid var(--accent); outline-offset:3px; }
.mobile-topic { display:none; }
.topbar { position:sticky; top:0; z-index:2; display:flex; justify-content:space-between; align-items:center; gap:16px; padding:16px max(28px,calc((100vw - 1310px) / 2)); border-bottom:1px solid var(--line); background:var(--paper); }
.brand { display:flex; gap:12px; align-items:center; font-size:18px; font-weight:600; text-decoration:none; }
.brand span { color:var(--accent); font-size:31px; line-height:1; }
.modes { display:flex; gap:4px; padding:4px; border:1px solid var(--line); border-radius:7px; }
.modes button { border:0; background:transparent; color:var(--muted); border-radius:4px; padding:9px 17px; font-size:12px; min-height:36px; }
.modes button:hover { background:var(--green); }
.modes button[aria-pressed="true"] { background:var(--ink); color:var(--white); }
.layout { display:grid; grid-template-columns:142px minmax(0,1fr); gap:45px; max-width:1366px; padding:30px 28px 55px; margin:auto; align-items:start; }
#topic-nav { display:grid; gap:5px; position:sticky; top:112px; padding-top:4px; }
#topic-nav a { display:block; padding:11px 12px; border-radius:5px; text-decoration:none; font-size:13px; }
#topic-nav a:hover { background:var(--green); }
#topic-nav a[aria-current] { background:var(--ink); color:var(--white); }
main { min-width:0; }
.intro { margin-bottom:31px; }
h1 { font:400 36px/1.15 Georgia,'Times New Roman',serif; letter-spacing:-.035em; margin:0 0 10px; }
.intro p { margin:0; color:var(--muted); font-size:13px; line-height:1.7; max-width:680px; }
.topic { margin-bottom:43px; }
.topic-heading { display:flex; align-items:baseline; flex-wrap:wrap; gap:8px 23px; margin-bottom:17px; }
h2 { font-size:19px; letter-spacing:-.025em; font-weight:500; margin:0; }
.tip { font-size:12px; color:var(--muted); margin:0; line-height:1.6; }
.exercise { display:grid; grid-template-columns:minmax(0,.75fr) minmax(0,1.25fr); gap:28px; padding:21px 0; border-top:1px solid var(--line); }
.exercise:last-child { border-bottom:1px solid var(--line); }
.prompt { font:400 22px/1.45 Georgia,'Times New Roman',serif; letter-spacing:-.02em; margin:6px 0 0; overflow-wrap:anywhere; }
.work-area { min-width:0; }
.write-form { display:flex; align-items:flex-start; gap:9px; }
.practice-input { display:block; width:100%; min-width:0; padding:10px 12px; min-height:46px; max-height:16rem; resize:vertical; border:1px solid #cbd4c7; border-radius:5px; background:var(--white); color:var(--ink); font-size:16px; line-height:1.5; }
.practice-input::placeholder { color:#768174; }
.practice-input[data-result="match"] { border-color:#8ba48c; background:#edf3e9; }
.practice-input[data-result="review"] { border-color:#be8958; }
.check-button { padding:10px 14px; min-height:46px; flex-shrink:0; border:1px solid var(--ink); border-radius:5px; background:var(--ink); color:var(--white); font-size:12px; }
.check-button:hover { background:#2c534b; }
.exercise-actions { display:flex; flex-wrap:wrap; gap:6px 20px; margin-top:6px; }
.text-button { border:0; padding:8px 0; color:var(--muted); background:transparent; font-size:12px; text-decoration:underline; text-underline-offset:3px; }
.text-button:hover { color:var(--ink); }
.feedback:empty { display:none; }
.hint { font-size:13px; line-height:1.65; color:var(--muted); margin:10px 0 0; }
.hint-start { font-size:13px; margin:6px 0 0; line-height:1.6; }
.hint-start span { font-weight:500; }
.answer { margin-top:12px; padding:15px 18px; background:#eeeede; border-radius:6px; }
.answer.match { background:var(--green); }
.answer-label { font-size:11px; color:var(--muted); }
.model { font:400 21px/1.5 Georgia,'Times New Roman',serif; overflow-wrap:anywhere; margin:6px 0; }
.lesson { font-size:12px; line-height:1.65; margin:8px 0 0; color:var(--muted); }
.audio-controls { display:flex; align-items:center; flex-wrap:wrap; gap:7px; margin:9px 0 2px; }
.audio-button { display:inline-flex; align-items:center; justify-content:center; gap:7px; padding:8px 10px; min-height:36px; border:1px solid #c5cec0; border-radius:5px; background:var(--white); color:var(--ink); font:12px/1.4 -apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif; }
.audio-button:hover { background:var(--green); }
.audio-button[aria-pressed="true"] { background:var(--ink); border-color:var(--ink); color:var(--white); }
.audio-button [aria-hidden] { font-size:10px; }
.audio-error { flex-basis:100%; font:12px/1.5 -apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif; color:var(--accent); }
.audio-error:empty { display:none; }
mark { background:var(--review); color:inherit; border-bottom:2px solid #b57835; padding:1px 0; }
.reference-table { width:100%; border-collapse:collapse; table-layout:fixed; }
.reference-table th { text-align:left; font-size:11px; font-weight:500; color:var(--muted); padding:0 20px 11px 0; border-bottom:1px solid var(--line); }
.reference-table td { font-size:13px; line-height:1.6; border-bottom:1px solid var(--line); padding:14px 20px 14px 0; vertical-align:middle; overflow-wrap:anywhere; }
.reference-table td.model { font-size:20px; }
.reference-table th:last-child,.reference-table td:last-child { padding-right:0; }
.sr-only { position:absolute; width:1px; height:1px; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; }
.skip-link { position:absolute; top:-70px; left:14px; padding:12px; z-index:5; background:var(--white); }
.skip-link:focus { top:12px; }
.print-credit { display:none; }
.site-credit { max-width:1366px; margin:auto; padding:0 28px 30px; font-size:11px; line-height:1.8; color:var(--muted); }
.credits-page { max-width:760px; margin:0 auto; padding:45px 24px; font-size:15px; line-height:1.8; }
.credits-page h1 { margin-top:28px; }
.credits-page h2 { margin-top:30px; }
.noscript { padding:25px; }
@media(max-width:1000px) {
 .layout { grid-template-columns:115px minmax(0,1fr); gap:24px; padding:26px 22px 45px; }
 #topic-nav a { padding:11px 8px; font-size:12px; }
 .topbar { padding:15px 22px; }
 .exercise { gap:19px; grid-template-columns:minmax(0,.65fr) minmax(0,1.35fr); }
 .prompt { font-size:20px; }
 .check-button { padding:10px; }
}
@media(max-width:720px) {
 .topbar { display:grid; grid-template-columns:auto minmax(0,1fr); padding:10px 16px; gap:8px 10px; }
 .brand { font-size:15px; gap:7px; min-height:44px; }
 .brand span { font-size:26px; }
 .modes { justify-self:end; gap:1px; padding:3px; }
 .modes button { padding:9px 8px; font-size:12px; min-height:44px; }
 .mobile-topic { display:block; grid-column:1/-1; width:100%; min-width:0; min-height:44px; padding:9px 12px; border:1px solid #cbd4c7; border-radius:5px; background:var(--white); color:var(--ink); font-size:16px; }
 .layout { display:block; padding:18px 18px 35px; }
 #topic-nav { display:none; }
 h1 { font-size:31px; }
 .intro { margin-bottom:27px; }
 .intro p,.tip,.hint,.hint-start,.lesson { font-size:14px; }
 .answer-label { font-size:12px; }
 .topic-heading { display:block; margin-bottom:15px; }
 .tip { margin-top:7px; }
 .exercise { grid-template-columns:1fr; gap:13px; padding:19px 0; }
 .prompt { margin:0; font-size:23px; }
 .practice-input { font-size:16px; resize:none; }
 .check-button { padding:10px 12px; font-size:13px; }
 .exercise-actions { gap:6px 12px; margin-left:-8px; }
 .text-button { min-height:44px; min-width:44px; padding:10px 8px; font-size:14px; }
 .audio-button { min-height:44px; font-size:14px; padding:9px 11px; }
 .answer { padding:14px; }
 .topic { margin-bottom:35px; }
 .reference-table td { font-size:14px; padding-right:12px; }
 .reference-table .model { font-size:21px; }
 .reference-table th { padding-right:12px; }
 .reference-table:not(.local-reference),.reference-table:not(.local-reference) tbody { display:block; }
 .reference-table:not(.local-reference) thead { position:absolute; width:1px; height:1px; overflow:hidden; clip-path:inset(50%); }
 .reference-table:not(.local-reference) tr { display:block; padding:16px 0; border-top:1px solid var(--line); }
 .reference-table:not(.local-reference) tr:last-child { border-bottom:1px solid var(--line); }
 .reference-table:not(.local-reference) td { display:block; padding:0; border:0; }
 .reference-table:not(.local-reference) td:first-child { color:var(--muted); margin-bottom:5px; }
 .reference-table .audio-controls { margin-top:10px; }
 .local-reference .model { font-size:18px; }
 .site-credit { padding:0 18px 24px; }
 .site-credit a { display:inline-flex; align-items:center; min-height:44px; font-size:12px; }
}
@media(max-width:360px) {
 .topbar { padding:11px 12px; gap:7px; }
 .brand { gap:5px; font-size:14px; }
 .modes button { padding:9px 6px; }
 .layout { padding-left:14px; padding-right:14px; }
 .write-form { gap:7px; }
 .check-button { padding:10px; }
}
@media(pointer:coarse) {
 #topic-nav a,button,.brand { min-height:44px; min-width:44px; }
 .text-button { padding-left:8px; padding-right:8px; }
}
@media print {
 .topbar,#topic-nav,.intro p,.exercise-actions,.write-form,.skip-link,.audio-controls { display:none!important; }
 .layout { display:block; padding:0; }
 body { background:white; color:black; }
 .topic { break-inside:avoid; margin-bottom:23px; }
 h1 { font-size:27px; } h2 { font-size:18px; }
 .model { font-size:15px; }
 .print-credit { display:block; font-size:9px; line-height:1.5; }
}