@font-face{font-family:"BIZ UDPGothic";src:url("../first-seating/fonts/BIZUDPGothic-Regular.ttf") format("truetype");font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:"BIZ UDPGothic";src:url("../first-seating/fonts/BIZUDPGothic-Bold.ttf") format("truetype");font-weight:700;font-style:normal;font-display:swap}
:root{color-scheme:light;--ink:#243436;--muted:#657577;--accent:#157e78;--line:#dce5e4;--soft:#eef6f4;--warm:#a64f3e}
*{box-sizing:border-box;letter-spacing:0}
html{scroll-behavior:smooth;scroll-padding-top:90px}
body{margin:0;background:#fff;color:var(--ink);font-family:"BIZ UDPGothic","BIZ UDPゴシック","Yu Gothic UI",Meiryo,sans-serif;font-size:16px;line-height:1.9;font-synthesis:none}
a{color:var(--accent);text-underline-offset:4px}button{font:inherit;font-size:13px;background:#fff;color:var(--ink);border:1px solid var(--line);border-radius:4px;padding:5px 13px;cursor:pointer;white-space:nowrap}button:hover{background:var(--soft);border-color:var(--accent)}a:focus-visible,button:focus-visible,summary:focus-visible{outline:2px solid var(--accent);outline-offset:4px}
.skip{position:fixed;top:-90px;left:16px;background:white;padding:8px;z-index:10}.skip:focus{top:8px}
.site-header{height:68px;padding:0 32px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;background:#fff;position:sticky;top:0;z-index:3}
.brand{font-weight:700;font-size:17px;text-decoration:none;color:var(--ink);display:flex;align-items:center;gap:18px}.brand span{font-size:12px;color:var(--muted);font-weight:400;border-left:1px solid var(--line);padding-left:18px}.header-actions{display:flex;align-items:center;gap:18px}.edition{font-size:12px;color:var(--muted)}
.layout{display:grid;grid-template-columns:210px minmax(0,940px);gap:52px;max-width:1290px;margin:0 auto;padding:0 32px}
.library{max-width:1060px;margin:0 auto;padding:0 32px}.guide-list{margin-bottom:36px}.guide-link{display:grid;grid-template-columns:45px minmax(0,1fr) 165px;gap:22px;align-items:center;padding:26px 0;border-bottom:1px solid var(--line);text-decoration:none;color:var(--ink)}.guide-link:hover h2{color:var(--accent)}.guide-index{font-size:24px;color:#b2c9c5;font-variant-numeric:tabular-nums}.guide-link h2{font-size:21px;margin-bottom:6px}.guide-link p{font-size:13px;color:var(--muted);margin:0}.guide-link .guide-scope{font-size:11px;color:var(--accent);margin-top:6px}.guide-link img{width:165px;height:100px;object-fit:cover;object-position:top;border:1px solid var(--line);border-radius:4px}.guide-navigation{font-size:12px;display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;padding:14px 0}.related-guides{margin-top:25px;border-top:1px solid var(--line);padding-top:16px}.related-guides a{display:block;font-size:13px;margin:8px 0}.download-links{display:flex;flex-wrap:wrap;gap:10px 22px;font-size:13px;padding:14px 0;border-block:1px solid var(--line);margin:20px 0}.mode-reference{width:100%;border-collapse:collapse;font-size:13px;margin:18px 0;table-layout:fixed}.mode-reference th,.mode-reference td{padding:10px 12px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line);overflow-wrap:anywhere}.mode-reference th{background:var(--soft)}.mode-reference th:first-child{width:34%}main,article,figure{overflow-wrap:anywhere}
.contents{position:sticky;top:98px;align-self:start;padding:0 0 32px}.nav-heading{font-size:14px;font-weight:700;margin:0 0 20px}.contents ol{padding:0;margin:0;list-style:none}.contents li{margin-bottom:6px}.contents nav a{display:flex;gap:12px;align-items:center;padding:9px 10px;border-radius:4px;font-size:13px;text-decoration:none;color:var(--muted);line-height:1.5}.contents nav a span{font-size:11px;font-variant-numeric:tabular-nums}.contents nav a:hover{background:#f4f7f6}.contents nav a[aria-current="step"]{background:var(--soft);color:var(--accent);font-weight:700}.reading-progress{margin:24px 10px 18px;font-size:11px;color:var(--muted)}progress{display:block;width:100%;height:4px;margin-top:10px;border:0;background:#e5eceb;accent-color:var(--accent)}progress::-webkit-progress-bar{background:#e5eceb}progress::-webkit-progress-value{background:var(--accent)}.help-link{font-size:12px;margin-left:10px}.sample-note{font-size:11px;color:var(--muted);margin:24px 10px}
main{min-width:0}.intro{padding:44px 0 36px;border-bottom:1px solid var(--line)}.eyebrow,.section-label{font-size:12px;color:var(--accent);font-weight:600;margin:0 0 8px}h1{font-size:34px;line-height:1.4;margin:0 0 18px}h2{font-size:24px;line-height:1.5;margin:0}h3{font-size:18px;line-height:1.6;margin:32px 0 12px}.lead{font-size:16px;color:var(--muted);margin:0 0 25px}p{margin:0 0 16px}
.scenario{display:flex;flex-wrap:wrap;gap:16px 30px;margin:0;padding:20px 0;border-top:1px solid #edf1f0}.scenario dt{font-size:11px;color:var(--muted)}.scenario dd{margin:2px 0 0;font-size:13px;font-weight:600}.before-start{border-left:3px solid var(--accent);padding:2px 0 2px 16px;margin-top:20px}.before-start strong{font-size:13px}.before-start p{font-size:13px;color:var(--muted);margin:4px 0 0}
.step{padding:40px 0;border-bottom:1px solid var(--line);scroll-margin-top:12px}.step-heading{display:flex;gap:18px;align-items:center;margin-bottom:24px}.step-number{font-size:32px;color:#b2c9c5;font-weight:700;font-variant-numeric:tabular-nums;line-height:1}.step-heading .section-label{margin:0 0 3px}.control-name{font-size:14px;color:var(--accent);font-weight:700}
.field-examples{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));margin:22px 0;border-block:1px solid var(--line);padding:12px 0;gap:12px}.field-examples dt{font-size:11px;color:var(--muted)}.field-examples dd{margin:3px 0 0;font-size:13px}
.screenshot{margin:24px 0;background:#f5f7f7;border:1px solid var(--line);border-radius:6px;overflow:hidden}.screenshot>a{display:block;cursor:zoom-in}.screenshot img{display:block;width:100%;height:auto}.screenshot.dialog-shot>a{padding:18px;background:#f1f5f4}.dialog-shot img{max-width:440px;margin:0 auto}.screenshot figcaption{display:flex;align-items:center;gap:10px;font-size:12px;line-height:1.7;color:var(--muted);background:#fff;padding:12px 14px;border-top:1px solid var(--line);flex-wrap:wrap}.caption-index{color:var(--accent);font-size:10px;white-space:nowrap}.screenshot figcaption button{margin-left:auto;font-size:11px;padding:3px 10px}
details{margin:16px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:12px 0;font-size:14px}details+details{margin-top:-17px;border-top:0}summary{cursor:pointer;font-size:14px;font-weight:600;color:var(--ink);padding:0 4px}details[open] summary{margin-bottom:16px;color:var(--accent)}details p,details ul{margin:14px 4px 0}details li{margin-bottom:10px}.supplement{display:grid;grid-template-columns:minmax(0,1fr) 260px;gap:25px;align-items:start}.supplement .screenshot{margin:0}.supplement .dialog-shot>a{padding:10px}.supplement p{font-size:14px}
.checkpoint{font-size:13px;color:var(--muted);margin:24px 0 0;display:flex;gap:14px;align-items:baseline}.checkpoint span{white-space:nowrap;color:var(--accent);font-weight:700}.notice{border-left:3px solid #c87a60;background:#fcf6f2;padding:12px 16px;margin:24px 0}.notice strong{font-size:14px;color:var(--warm)}.notice p{font-size:13px;margin:5px 0 0}
.example-rules{border-block:1px solid var(--line);margin:22px 0;padding:6px 0}.example-rules p{display:flex;align-items:baseline;gap:16px;margin:0;padding:10px 0;font-size:13px}.example-rules p+p{border-top:1px solid #edf1f0}.example-rules span{color:var(--muted);font-size:11px;white-space:nowrap}.example-rules strong{font-weight:500;flex:1}.example-rules small{font-size:11px;white-space:nowrap;color:var(--accent)}.instruction-list{padding-left:24px;font-size:15px}.instruction-list li{margin-bottom:10px;padding-left:6px}.finish{margin-top:32px;padding:24px 0 0;border-top:1px solid var(--line)}.finish h3{margin:4px 0 10px}.finish p{font-size:14px}.finish a{font-size:13px}
.troubleshooting{padding:40px 0}.troubleshooting h2{margin-bottom:24px;font-size:22px}.article-footer{border-top:1px solid var(--line);padding:24px 0 36px;color:var(--muted);font-size:11px}.article-footer p{margin:0 0 6px}
dialog{border:0;border-radius:6px;padding:0;width:min(1400px,94%);max-height:94dvh;background:#f5f7f7;color:var(--ink)}dialog::backdrop{background:rgb(20 32 31 / .7)}.viewer-toolbar{display:flex;align-items:center;justify-content:space-between;padding:10px 16px;background:#fff;gap:16px}.viewer-toolbar p{font-size:13px;margin:0}.viewer-image{overflow:auto;max-height:calc(94dvh - 65px);padding:16px;text-align:center}.viewer-image img{max-width:100%;height:auto;vertical-align:top}
@media(max-width:1000px){.layout{grid-template-columns:170px minmax(0,1fr);gap:26px;padding:0 22px}.site-header{padding:0 22px}.contents nav a{font-size:12px;padding:8px 6px}.supplement{grid-template-columns:minmax(0,1fr) 220px}}
@media(max-width:720px){html{scroll-padding-top:78px}.site-header{height:60px;padding:0 16px}.brand{font-size:14px;gap:8px}.brand span{font-size:10px;padding-left:8px}.edition{display:none}.header-actions{gap:8px}.layout{display:block;padding:0 18px}.contents{position:static;padding:18px 0 0}.nav-heading,.reading-progress,.sample-note,.help-link{display:none}.contents ol{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:3px 6px}.contents li{margin:0}.contents nav a{padding:8px;font-size:12px}.intro{padding-top:28px}h1{font-size:28px}h2{font-size:21px}.lead{font-size:14px}.lead br{display:none}.scenario{gap:14px 22px}.step{padding:30px 0}.step-heading{gap:13px}.step-number{font-size:28px}body{font-size:15px}.field-examples{grid-template-columns:repeat(2,minmax(0,1fr))}.supplement{display:block}.supplement .screenshot{margin-top:20px}.supplement .dialog-shot img{max-width:340px}.checkpoint{display:block}.checkpoint span{display:block;margin-bottom:4px}.screenshot figcaption{font-size:11px}.example-rules p{flex-wrap:wrap;gap:4px 10px}.example-rules strong{flex-basis:calc(100% - 42px)}.example-rules small{margin-left:36px}.viewer-toolbar p{font-size:11px}.viewer-image{padding:6px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
@media(max-width:720px){.library{padding:0 18px}.guide-link{grid-template-columns:30px minmax(0,1fr);gap:12px;padding:22px 0}.guide-link img{display:none}.guide-link h2{font-size:18px}.guide-index{font-size:22px}.mode-reference th,.mode-reference td{padding:8px 6px;font-size:12px}.guide-navigation{font-size:11px}.download-links{display:block}.download-links a{display:block;margin:8px 0}}
@media print{html{scroll-behavior:auto}body{font-size:11pt}.site-header{position:static;padding:0;height:45px}.header-actions,.contents,.skip,figcaption button,.finish a,dialog{display:none!important}.layout{display:block;padding:0;max-width:none}h1{font-size:24pt}h2{font-size:18pt}.intro{padding-top:20px}.step{padding:22px 0}.screenshot{break-inside:avoid;max-width:680px;margin:16px auto}.dialog-shot img{max-width:250px}.notice,.checkpoint{break-inside:avoid}details{display:none}.article-footer{font-size:9pt}}