.terrain-reference .intro-nav{display:grid;grid-template-columns:repeat(auto-fit,minmax(155px,1fr));gap:16px;margin:30px 0 45px}.intro-nav a{padding-top:12px;border-top:2px solid var(--line);text-decoration:none;font-size:13px;line-height:1.9}.intro-nav a>span{display:block;font:12px var(--mono);color:var(--muted);margin-bottom:9px}.intro-chapter{padding:8px 0 38px;margin-bottom:30px;border-bottom:1px solid var(--line);scroll-margin-top:110px}.intro-chapter>header{display:flex;align-items:baseline;gap:15px}.intro-chapter>header>span{font:14px var(--mono);color:var(--green)}.terrain-reference .intro-chapter h2{font-size:23px;line-height:1.7;margin:0 0 20px}.terrain-reference .intro-chapter>p{font-size:16px;line-height:2;margin:16px 0 22px}.intro-chapter b{font-weight:600}.intro-figure{margin:26px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:22px 0}.intro-figure figcaption{font-size:12px;line-height:1.9;color:var(--muted);margin-top:20px}.intro-comparison{display:grid;grid-template-columns:1fr 1fr;gap:30px;align-items:start}.terrain-reference .intro-figure h3{font-size:15px;margin:0 0 18px;line-height:1.9}.terrain-reference .intro-figure p{font-size:13px;line-height:1.9;color:var(--muted);margin:15px 0 0}.intro-figure svg{display:block;width:100%;max-height:265px;aspect-ratio:1.5;overflow:visible}.intro-solid{fill:var(--green)}.intro-air{fill:var(--muted);opacity:.3}.intro-boundary{stroke:var(--accent);stroke-width:.075;fill:none}.intro-height-columns{display:flex;gap:7px;align-items:end;height:230px;max-height:265px;border-bottom:1px solid var(--line)}.intro-height-columns i{flex:1;background:var(--soft);border-top:2px solid var(--green)}.intro-data-row{display:grid;grid-template-columns:1fr 32px 1fr;gap:20px;align-items:center}.intro-concept-arrow{font-size:25px;color:var(--muted);text-align:center}.intro-group-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;max-width:310px;margin:auto}.intro-group-grid>div{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;border:1px solid var(--line);padding:12px}.intro-group-grid i{aspect-ratio:1;border-radius:50%;background:var(--green);opacity:.7}.intro-definitions{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:22px;margin:28px 0}.intro-definitions dt{font-size:15px;font-weight:500;margin-bottom:9px;color:var(--green)}.intro-definitions dd{font-size:14px;line-height:1.9;margin:0}.intro-chain{list-style:none;counter-reset:chain;display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:18px;padding:0;margin:0}.intro-chain li{border-top:2px solid var(--line);padding-top:14px}.intro-chain span{display:block;font:12px var(--mono);color:var(--muted);margin-bottom:14px}.intro-chain b{display:block;font-size:14px;font-weight:500}.terrain-reference .intro-chain p{font-size:13px}.intro-next{display:inline-block;font-size:14px;margin-top:18px;text-underline-offset:5px}.intro-advanced{border-top:1px solid var(--line);padding-top:25px;margin:35px 0}.intro-advanced>summary{font-size:17px;line-height:1.9;color:var(--ink);padding:12px 0}.intro-advanced>p{font-size:14px;color:var(--muted);line-height:1.9}.intro-advanced .study-toc{margin-top:25px}.intro-primary-title{margin-top:15px}.intro-primary-title>p{font-size:16px;line-height:2}.td3-inspector-summary{font-size:13px;line-height:1.9;margin:0 0 18px}.td3-inspector>details>summary{font-size:14px;line-height:1.9}.td3-inspector details[open]>summary{margin-bottom:17px}.td3-inspector details>label{display:flex;flex-wrap:wrap;justify-content:space-between;gap:8px;font-size:12px;line-height:1.9}.td3-inspector details>label input{width:100%;accent-color:var(--green)}
.td3-inspector>.td3-inspector-summary,.td3-inspector>details{grid-column:1/-1}.td3-inspector .td3-tree-root{margin-top:15px}.td3-inspector .td3-parents{margin-bottom:15px}
@media(max-width:800px){.intro-chain{grid-template-columns:1fr}.intro-chain li{display:grid;grid-template-columns:30px 1fr;gap:6px 15px;padding:14px 0 0}.intro-chain span{grid-row:1/3;margin:0}.intro-chain p{grid-column:2;margin-top:0!important}.intro-comparison{gap:20px}.intro-definitions{grid-template-columns:1fr;gap:17px}.intro-definitions>div{display:grid;grid-template-columns:90px 1fr;gap:15px}.intro-definitions dt{font-size:14px}.td3-inspector>details{grid-column:1/-1}}
@media(max-width:600px){.intro-comparison,.intro-data-row{grid-template-columns:1fr;gap:20px}.intro-concept-arrow{transform:rotate(90deg)}.intro-figure svg{max-height:240px}.intro-height-columns{height:170px}.terrain-reference .intro-chapter h2{font-size:21px}.terrain-reference .intro-chapter>p{font-size:15px}.intro-nav{grid-template-columns:1fr!important;gap:14px!important}.intro-nav a>span{display:inline;margin-right:12px}.intro-nav a{padding-top:10px}.intro-definitions>div{grid-template-columns:75px 1fr;gap:12px}.intro-advanced>summary{font-size:16px}.intro-figure{padding:19px 0}.td3-inspector details>label{margin-top:15px}}