:root{color-scheme:light;--ink:#183c50;--muted:#70828e;--line:#e3e9ed;--teal:#168b7d}
*{box-sizing:border-box}body{margin:0;background:#f6f8fa;color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}a:focus-visible{outline:3px solid #2979b8;outline-offset:6px}
.page-header,main,footer{width:calc(100% - 96px);max-width:1120px;margin-inline:auto}.page-header{min-height:108px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);font-size:13px;color:var(--muted)}.domain{font-size:18px;font-weight:600;letter-spacing:.01em;color:var(--ink)}
main{padding:64px 0 56px}.eyebrow{font-size:13px;font-weight:500;letter-spacing:.12em;margin:0 0 18px;color:var(--teal)}h1{font-size:clamp(32px,4vw,48px);font-weight:600;letter-spacing:-.025em;line-height:1.35;margin:0}.intro-copy{color:var(--muted);font-size:15px;line-height:1.9;margin:22px 0 0}.entry-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:44px}
.entry-card{background:#fff;border:1px solid var(--line);border-radius:18px;padding:34px;display:flex;flex-direction:column;min-width:0;min-height:348px}.card-brand{display:flex;align-items:center;gap:14px;min-height:44px}.card-brand img{object-fit:contain;flex:none}.card-brand h2{font-size:25px;font-weight:600;letter-spacing:-.01em;line-height:1.4;margin:0}.card-brand .yddx-wordmark{font-family:"Songti SC","STSong",serif;font-weight:400;letter-spacing:.04em;color:#163e5d}.card-tagline{font-size:14px;line-height:1.6;margin:18px 0 0;color:#566d7c}.card-description{font-size:14px;line-height:1.9;color:var(--muted);margin:22px 0 28px}.tool-note{font-size:12px;color:#82949f;line-height:1.8;margin:22px 0 0}
.tool-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:12px;margin-top:auto}.ai .tool-grid{grid-template-columns:minmax(0,1fr)}.tool-link{min-width:0;min-height:94px;display:flex;flex-direction:column;justify-content:center;gap:10px;padding:17px 15px;border:1px solid #dce6eb;border-radius:11px;background:#f7fafb;color:#167b6e;transition:background .2s,border-color .2s}.tool-link:hover{background:#edf4f7;border-color:#a5c1cc}.tool-heading{display:flex;align-items:center;gap:8px;min-height:24px}.tool-heading svg{flex:none}.tool-heading h3{font-size:17px;line-height:1.4;margin:0;font-weight:600}.tool-arrow{margin-left:auto;color:currentColor;opacity:.7;font-size:17px}.tool-description{font-size:12px;line-height:1.6;color:#647e8c}.ai-tool{color:#285c7b}.drawing-tool{color:#236c8d}.tool-link:focus-visible{outline-offset:3px}
footer{border-top:1px solid var(--line);padding:22px 0 32px;display:flex;justify-content:space-between;align-items:center;gap:20px;font-size:12px;color:#82949f}footer nav{display:flex;gap:24px}footer a:hover{color:var(--ink)}
@media(max-width:760px){.page-header,main,footer{width:calc(100% - 40px)}.page-header{min-height:76px;font-size:11px}.domain{font-size:16px}main{padding:38px 0 32px}.entry-grid{grid-template-columns:1fr;gap:16px;margin-top:30px}.entry-card{padding:26px;min-height:0}.card-brand h2{font-size:23px}h1{font-size:33px}.intro-copy{font-size:14px;margin-top:16px}.card-description{margin-top:18px}footer{align-items:flex-start;flex-direction:column;gap:16px;padding-bottom:28px}footer nav{gap:22px}}
@media(min-width:761px) and (max-width:980px){.entry-card{padding:28px}.tool-grid{grid-template-columns:1fr;min-height:200px}.ai .tool-grid{align-content:end}.tool-link{padding:14px 16px;gap:8px}}
@media(max-width:420px){.tool-grid{grid-template-columns:1fr;gap:10px}.tool-link{padding:14px 16px;gap:5px}.tool-description{padding-left:30px}}
@media(prefers-reduced-motion:reduce){.tool-link{transition:none}}