@font-face{font-family:Barlow;src:url('fonts/BarlowCondensed-Light.ttf') format('truetype');font-style:normal;font-weight:300;font-display:swap}
@font-face{font-family:Plex;src:url('fonts/IBMPlexMono-Regular.ttf') format('truetype');font-weight:400;font-display:swap}
:root{color-scheme:dark;--ink:#080f12;--panel:#0d171a;--text:#e5e9de;--muted:#9bada7;--line:#2d3e3e;--amber:#ffb347;--mint:#b6dac6;--display:Barlow,'PingFang SC','Microsoft YaHei',sans-serif;--mono:Plex,'SFMono-Regular',Consolas,monospace;--body:'Helvetica Neue','PingFang SC','Microsoft YaHei',sans-serif}
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56px;display:flex;align-items:center;gap:35px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-family:var(--mono);font-size:11px;line-height:1.5;letter-spacing:.07em}.brand svg{width:36px;height:36px;color:var(--mint)}nav{display:flex;gap:30px;margin-left:auto}nav a{font-size:13px;text-decoration:none}nav a:hover,.links a:hover{color:var(--amber)}.languages{display:flex;padding-left:20px;border-left:1px solid var(--line);gap:5px}.languages button{border:0;background:transparent;color:var(--muted);padding:7px;font-size:12px}.languages button[aria-pressed=true]{color:var(--amber);box-shadow:0 1px var(--amber)}main{padding:0 56px}.hero{padding:45px 0 48px}.hero-top{display:flex;justify-content:space-between;align-items:center;gap:20px}.eyebrow,.discipline{font:11px/1.6 var(--mono);letter-spacing:.10em;text-transform:uppercase}.eyebrow{color:var(--amber)}.discipline{color:var(--muted);font-size:10px}.hero-body{display:grid;grid-template-columns:1.6fr 1fr;align-items:end;gap:50px;margin-top:30px}h1{font-size:clamp(75px,8.8vw,144px);line-height:.9;letter-spacing:-.025em}h1 em{font-style:normal;color:var(--mint)}.hero-intro{max-width:360px;justify-self:end;padding-bottom:6px}.cross{display:block;font-family:var(--mono);font-size:28px;color:var(--amber);margin-bottom:22px}.hero-intro p{font-size:16px;color:var(--muted);line-height:1.7}.text-link{display:inline-block;margin-top:24px;font-size:13px;text-decoration:none;color:var(--text)}.study{border:1px solid var(--line);scroll-margin-top:24px}.study-bar{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:17px 24px;font:10px/1.5 var(--mono);letter-spacing:.06em}.study-bar 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svg{width:30px;height:38px;stroke:currentColor;fill:none;stroke-width:1}.viewport-note{position:absolute;bottom:25px;right:24px;font:8px/1.5 var(--mono);color:var(--muted);letter-spacing:.05em}.transport{display:flex;gap:16px;align-items:center;padding:17px 24px}.transport button{min-height:36px;background:transparent;border:1px solid var(--line);padding:8px 13px;font:11px var(--mono)}.transport #play{background:var(--mint);border-color:var(--mint);color:var(--ink);min-width:145px}.transport #play:hover{background:var(--text)}#restart{font-size:22px;line-height:1;padding:4px 11px}.transport input{flex:1;min-width:40px;accent-color:var(--amber);height:26px;cursor:pointer}.transport output{font:10px var(--mono);color:var(--muted);white-space:nowrap;min-width:95px;text-align:right}.chapters{display:grid;grid-template-columns:repeat(5,1fr);border-top:1px solid var(--line)}.chapters button{background:transparent;border:0;border-right:1px solid var(--line);text-align:left;padding:20px 22px;position:relative}.chapters button:last-child{border-right:0}.chapters button small{font:9px var(--mono);color:var(--muted);display:block;margin-bottom:10px}.chapters button span{font-size:13px}.chapters button[aria-pressed=true]{background:#182321;box-shadow:inset 0 2px var(--amber)}.chapters button[aria-pressed=true] small{color:var(--amber)}.chapters button:hover{background:#182321}.study-caption{border-top:1px solid var(--line);padding:24px;display:grid;grid-template-columns:1.3fr 1fr;gap:65px}.study-caption p{font-size:12px;line-height:1.7;color:var(--muted)}.study-caption p:first-child{font-size:14px;color:var(--text)}.noscript{padding:20px;color:var(--amber)}.grammar,.make,.notes{padding:100px 0;border-bottom:1px solid var(--line)}.section-heading{display:grid;grid-template-columns:1.4fr 1fr;align-items:end;gap:70px;margin-bottom:55px}.section-heading 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0}.copy:hover{color:var(--amber)}#copy-status{font-size:11px;color:var(--mint);display:block;margin-top:7px}.prompt{display:grid;grid-template-columns:1fr 2.3fr;gap:25px 60px;background:var(--panel);border-top:1px solid var(--amber);padding:35px}.prompt blockquote{margin:0;font-size:20px;line-height:1.6}.prompt a{grid-column:2;font-size:12px;color:var(--mint)}.package-note{max-width:780px;font-size:12px;color:var(--muted);margin-top:24px}.links{display:flex;flex-wrap:wrap;gap:18px 30px;margin-top:32px}.links a{font-size:12px}.credits{padding:75px 0}.credits h2{font-size:52px;margin:18px 0 25px}.credits>p:not(.eyebrow){max-width:790px;font-size:14px;color:var(--muted)}.credits>.font-note{font-size:11px!important;margin-top:38px;max-width:690px!important}.font-links{margin-top:12px}.font-links a{font-size:10px;color:var(--muted)}footer{display:flex;justify-content:space-between;gap:25px;padding:30px 56px 40px;border-top:1px solid var(--line);font-size:11px;color:var(--muted)}footer a{text-decoration:none}footer .brand{color:var(--text);font-size:10px}html[lang=zh-CN] h1{font-size:clamp(56px,6.5vw,100px);line-height:1.15;font-weight:300}html[lang=zh-CN] .section-heading h2{font-size:clamp(44px,4.9vw,65px);line-height:1.25}html[lang=zh-CN] .credits h2{font-size:38px}
@media(min-width:1600px){main{padding:0 72px}}
@media(max-width:1000px){.masthead{padding:24px 32px;gap:20px}main{padding:0 32px}nav{gap:20px}.hero-body{gap:35px;grid-template-columns:1.5fr 1fr}.hero-intro p{font-size:14px}.chapters button{padding:18px 14px}.principles{gap:28px}.steps{gap:24px}.palette{gap:15px}.palette>div{column-gap:8px}.palette span{font-size:11px}.prompt{gap:25px 30px}.study-caption{gap:30px}footer{padding:30px 32px;flex-wrap:wrap}.grammar,.make,.notes{padding:75px 0}}
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@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

.final-screening{--screen-accent:#ffb347;--screen-on-accent:#080f12}