/* Room Lab — drafting-sheet design system
   Paper, ink and one redline accent. Measurements are set in mono. */
:root{
  --paper:#F4F1EA; --paper-2:#ECE7DC; --sheet:#FBFAF7;
  --ink:#1C1B18; --ink-2:#4B4840; --ink-3:#7D786C; --ink-4:#A9A497;
  --rule:#D9D2C3; --rule-2:#E6E0D3;
  --red:#D8462B; --red-ink:#A8321C; --red-wash:#F7E3DC;
  --blue:#2A4FBF; --blue-wash:#E3E8F6; --green:#2F6B4F; --green-wash:#E1EDE5;
  --sans:'Pretendard Variable',Pretendard,-apple-system,BlinkMacSystemFont,'Apple SD Gothic Neo','Segoe UI','Malgun Gothic',system-ui,sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --gutter:clamp(16px,4vw,40px);
  --max:1240px;
  --header:64px;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:calc(var(--header) + 16px)}
@media (prefers-reduced-motion:no-preference){html{scroll-behavior:smooth}}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.7;letter-spacing:-.006em;word-break:keep-all;overflow-wrap:break-word;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
html[lang=en] body{letter-spacing:0;word-break:normal}
img,svg{max-width:100%;height:auto;display:block}
a{color:inherit;text-decoration-thickness:1px;text-underline-offset:.22em}
a:hover{text-decoration-color:var(--red)}
button,input,select{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{opacity:.35;cursor:not-allowed}
:focus-visible{outline:2px solid var(--blue);outline-offset:3px}
::selection{background:#F2C8BB}
.wrap{width:min(var(--max),100% - var(--gutter)*2);margin-inline:auto}
.wrap-narrow{width:min(760px,100% - var(--gutter)*2);margin-inline:auto}
.skip-link{position:absolute;left:12px;top:-60px;z-index:100;background:var(--ink);color:var(--paper);padding:10px 14px;font-size:14px;text-decoration:none}
.skip-link:focus{top:12px}
.label{font-family:var(--mono);font-size:11.5px;line-height:1.4;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-3);font-weight:500}
.num{font-family:var(--mono);font-feature-settings:"tnum";letter-spacing:0}
.muted{color:var(--ink-3)}

/* ---------- header ---------- */
.site-header{position:sticky;top:0;z-index:40;background:color-mix(in srgb,var(--paper) 92%,transparent);-webkit-backdrop-filter:saturate(1.2) blur(12px);backdrop-filter:saturate(1.2) blur(12px);border-bottom:1px solid var(--rule)}
@supports not (background:color-mix(in srgb,red,blue)){.site-header{background:rgba(244,241,234,.94)}}
.header-inner{height:var(--header);display:flex;align-items:center;gap:28px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;flex-shrink:0}
.brand-mark{width:26px;height:26px;flex-shrink:0}
.brand-name{font-weight:700;font-size:17px;letter-spacing:-.03em;line-height:1}
html[lang=en] .brand-name{letter-spacing:-.02em}
.brand-sub{font-family:var(--mono);font-size:10px;letter-spacing:.12em;color:var(--ink-3);border-left:1px solid var(--rule);padding-left:9px;margin-left:1px;line-height:1}
.nav{display:flex;align-items:center;gap:26px;margin-left:auto}
.nav a{text-decoration:none;font-size:14.5px;color:var(--ink-2);font-weight:500;padding:6px 0;position:relative}
.nav a:hover{color:var(--ink)}
.nav a[aria-current=page]{color:var(--ink)}
.nav a[aria-current=page]::after{content:"";position:absolute;left:0;right:0;bottom:-2px;height:2px;background:var(--red)}
.nav .nav-cta{background:var(--ink);color:var(--paper);padding:9px 15px;font-weight:600;font-size:14px;border-radius:2px}
.nav .nav-cta:hover{color:var(--paper);background:#000}
.nav .nav-cta::after{display:none}
.nav .nav-cta[aria-current=page]{color:var(--paper)}
.lang-switch{display:flex;align-items:center;gap:2px;font-size:13px;flex-shrink:0;border:1px solid var(--rule);border-radius:2px;padding:2px;background:var(--sheet)}
.lang-switch a{text-decoration:none;color:var(--ink-3);padding:4px 9px;line-height:1.3;font-weight:500;border-radius:1px}
.lang-switch a:hover{color:var(--ink)}
.lang-switch a.selected{background:var(--ink);color:var(--paper)}
.lang-divider{display:none}
.menu-toggle{display:none;align-items:center;gap:8px;background:none;border:0;padding:8px 2px;font-size:14px;font-weight:600;color:var(--ink)}
.menu-icon{width:18px;height:10px;position:relative;display:inline-block}
.menu-icon::before,.menu-icon::after{content:"";position:absolute;left:0;right:0;height:1.5px;background:currentColor;transition:transform .2s}
.menu-icon::before{top:0}.menu-icon::after{bottom:0}
.menu-toggle[aria-expanded=true] .menu-icon::before{transform:translateY(4.25px) rotate(45deg)}
.menu-toggle[aria-expanded=true] .menu-icon::after{transform:translateY(-4.25px) rotate(-45deg)}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:48px;padding:0 22px;background:var(--ink);color:var(--paper);border:1px solid var(--ink);border-radius:2px;font-size:15px;font-weight:600;text-decoration:none;line-height:1.2;transition:background .15s,color .15s,border-color .15s;white-space:nowrap}
.btn:hover{background:#000;color:var(--paper)}
.btn .arrow{font-family:var(--mono);font-weight:400;transition:transform .15s}
.btn:hover .arrow{transform:translateX(3px)}
.btn--ghost{background:transparent;color:var(--ink);border-color:var(--ink)}
.btn--ghost:hover{background:var(--ink);color:var(--paper)}
.btn--red{background:var(--red);border-color:var(--red)}
.btn--red:hover{background:var(--red-ink);border-color:var(--red-ink)}
.btn--sm{min-height:38px;padding:0 14px;font-size:14px}
.btn--block{width:100%}
.link-arrow{font-weight:600;text-decoration:none;border-bottom:1px solid var(--ink);padding-bottom:2px;display:inline-flex;gap:8px;align-items:baseline}
.link-arrow:hover{color:var(--red-ink);border-color:var(--red)}

/* ---------- home: hero ---------- */
.hero{padding:clamp(40px,7vw,96px) 0 clamp(56px,8vw,112px);border-bottom:1px solid var(--rule)}
.hero-grid{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,.8fr);gap:clamp(32px,6vw,88px);align-items:center}
.hero h1{font-size:clamp(38px,5.4vw,68px);line-height:1.04;letter-spacing:-.045em;font-weight:700;margin:22px 0 0}
html[lang=en] .hero h1{letter-spacing:-.035em;line-height:1}
.hero h1 .strike{position:relative;white-space:nowrap}
.hero h1 .strike::after{content:"";position:absolute;left:-2%;right:-2%;top:54%;height:.07em;background:var(--red);transform:rotate(-2deg)}
.hero-lede{font-size:clamp(17px,1.5vw,19px);line-height:1.65;color:var(--ink-2);max-width:31em;margin:28px 0 0}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:36px}
.hero-facts{display:flex;flex-wrap:wrap;margin:44px 0 0;padding:0;list-style:none;border-top:1px solid var(--rule)}
.hero-facts li{padding:14px 22px 0 0;margin-right:22px;font-size:14px;color:var(--ink-2);border-right:1px solid var(--rule);line-height:1.4}
.hero-facts li:last-child{border-right:0}
.hero-facts b{display:block;font-family:var(--mono);font-size:11px;font-weight:500;color:var(--ink-3);letter-spacing:.07em;margin-bottom:4px}

/* drawing sheet */
.sheet{background:var(--sheet);border:1px solid var(--ink);box-shadow:8px 8px 0 var(--paper-2)}
.sheet-plot{padding:clamp(14px,2.4vw,28px)}
.sheet-plot svg{width:100%;max-height:520px}
.titleblock{display:grid;grid-template-columns:1.4fr 1fr 1fr;border-top:1px solid var(--ink);margin:0}
.titleblock div{padding:10px 14px;border-right:1px solid var(--ink);min-width:0}
.titleblock div:last-child{border-right:0}
.titleblock dt{font-family:var(--mono);font-size:10px;letter-spacing:.08em;color:var(--ink-3);text-transform:uppercase}
.titleblock dd{margin:2px 0 0;font-size:14px;font-weight:600;line-height:1.35;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.titleblock dd.num{font-weight:500}

/* ---------- sections ---------- */
.band{padding:clamp(64px,9vw,128px) 0;border-bottom:1px solid var(--rule)}
.band:last-of-type{border-bottom:0}
.band-head{display:grid;grid-template-columns:120px minmax(0,1fr) minmax(0,.8fr);gap:24px 40px;align-items:end;margin-bottom:clamp(36px,5vw,64px)}
.band-head .label{align-self:start;padding-top:12px}
.band-head h2{font-size:clamp(28px,3.4vw,46px);line-height:1.15;letter-spacing:-.035em;margin:0;font-weight:700}
html[lang=en] .band-head h2{letter-spacing:-.025em}
.band-head p{margin:0;color:var(--ink-2);font-size:16px}
.band-head .band-link{justify-self:start}

/* contrast block: one layout, two numbers */
.contrast{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);border:1px solid var(--ink);background:var(--sheet)}
.contrast-plot{padding:clamp(18px,3vw,36px);border-right:1px solid var(--ink)}
.contrast-plot svg{max-height:440px;margin:auto}
.contrast-read{display:flex;flex-direction:column}
.metric{padding:clamp(20px,3vw,34px);border-bottom:1px solid var(--rule)}
.metric-value{font-family:var(--mono);font-size:clamp(40px,5.5vw,72px);line-height:1;letter-spacing:-.04em;font-weight:500}
.metric-value.is-red{color:var(--red)}
.metric p{margin:12px 0 0;color:var(--ink-2);max-width:30em}
.contrast-foot{padding:clamp(20px,3vw,34px);margin-top:auto;font-size:15px;color:var(--ink-2)}
.contrast-foot p{margin:0 0 14px}

/* study index */
.study-list{list-style:none;margin:0;padding:0;border-top:1px solid var(--ink)}
.study-row{display:grid;grid-template-columns:56px minmax(0,1fr) 170px 96px 88px;gap:24px;align-items:center;padding:22px 0;border-bottom:1px solid var(--rule);text-decoration:none;transition:background .15s}
.study-row:hover{background:var(--sheet)}
.study-row:hover .study-title{text-decoration:underline;text-decoration-color:var(--red);text-decoration-thickness:2px}
.study-no{font-family:var(--mono);font-size:13px;color:var(--ink-3);padding-left:4px}
.study-title{font-size:clamp(17px,1.6vw,20px);font-weight:600;line-height:1.4;letter-spacing:-.02em;display:block}
.study-cat{display:block;font-size:13px;color:var(--ink-3);margin-top:4px}
.study-spec{font-family:var(--mono);font-size:13px;color:var(--ink-2)}
.study-time{font-family:var(--mono);font-size:13px;color:var(--ink-3);text-align:right}
.study-thumb{width:88px;height:64px;border:1px solid var(--rule);background:var(--sheet);padding:4px}
.study-thumb svg{width:100%;height:100%}

/* steps */
.steps{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:0;border-top:1px solid var(--ink)}
.steps li{padding:28px 32px 8px 0;margin-right:32px;border-right:1px solid var(--rule)}
.steps li:last-child{border-right:0;margin-right:0}
.steps .step-no{font-family:var(--mono);font-size:44px;line-height:1;color:var(--red);font-weight:400}
.steps h3{font-size:19px;margin:22px 0 8px;letter-spacing:-.02em}
.steps p{margin:0;color:var(--ink-2);font-size:15.5px}

/* dark call to action */
.cta-band{background:var(--ink);color:var(--paper);padding:clamp(56px,8vw,104px) 0}
.cta-inner{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:32px;align-items:end}
.cta-band h2{font-size:clamp(30px,4.2vw,58px);line-height:1.1;letter-spacing:-.04em;margin:0;max-width:14em}
html[lang=en] .cta-band h2{letter-spacing:-.03em}
.cta-band p{color:#BDB8AC;margin:16px 0 0;max-width:34em}
.cta-band .btn{background:var(--paper);color:var(--ink);border-color:var(--paper)}
.cta-band .btn:hover{background:#fff}

/* ---------- footer ---------- */
.site-footer{border-top:1px solid var(--ink);padding:56px 0 32px;background:var(--paper)}
.footer-grid{display:grid;grid-template-columns:minmax(0,1.6fr) repeat(2,minmax(0,1fr));gap:40px}
.footer-about p{color:var(--ink-2);font-size:14px;max-width:30em;margin:16px 0 0}
.footer-col h2{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-3);font-weight:500;margin:0 0 14px}
.footer-col ul{list-style:none;margin:0;padding:0;display:grid;gap:8px}
.footer-col a{text-decoration:none;font-size:14.5px;color:var(--ink-2)}
.footer-col a:hover{color:var(--ink);text-decoration:underline}
.footer-base{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-top:56px;padding-top:18px;border-top:1px solid var(--rule);font-size:13px;color:var(--ink-3)}
.footer-base a{color:var(--ink-2)}

/* ---------- inner pages ---------- */
.page-head{padding:clamp(44px,7vw,96px) 0 clamp(32px,4vw,56px);border-bottom:1px solid var(--rule)}
.page-head h1{font-size:clamp(34px,5vw,64px);line-height:1.08;letter-spacing:-.04em;margin:16px 0 0;font-weight:700;max-width:16em}
html[lang=en] .page-head h1{letter-spacing:-.03em}
.page-head .lede{font-size:clamp(17px,1.5vw,19px);color:var(--ink-2);max-width:36em;margin:20px 0 0}
.page-head--split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.7fr);gap:40px;align-items:end}
.page-head--split .lede{margin:0}
.breadcrumb{font-size:13px;color:var(--ink-3);display:flex;gap:8px;flex-wrap:wrap;padding-top:28px}
.breadcrumb a{color:var(--ink-2);text-decoration:none}
.breadcrumb a:hover{text-decoration:underline}

/* long-form text */
.prose{font-size:17px;line-height:1.85;color:var(--ink)}
html[lang=en] .prose{line-height:1.7;font-size:17.5px}
.prose>*:first-child{margin-top:0}
.prose p{margin:0 0 1.15em}
.prose h2{font-size:clamp(22px,2.2vw,27px);line-height:1.35;letter-spacing:-.03em;margin:2.3em 0 .7em;font-weight:700}
html[lang=en] .prose h2{letter-spacing:-.02em}
.prose h3{font-size:19px;margin:1.8em 0 .5em;letter-spacing:-.02em}
.prose ul,.prose ol{padding-left:1.25em;margin:0 0 1.3em}
.prose li{margin:.35em 0;padding-left:.2em}
.prose li::marker{color:var(--ink-3);font-family:var(--mono);font-size:.9em}
.prose strong{font-weight:650}
.prose code{font-family:var(--mono);font-size:.86em;background:var(--paper-2);padding:.1em .35em;border-radius:2px}
.prose blockquote{margin:1.6em 0;padding:4px 0 4px 20px;border-left:3px solid var(--red);color:var(--ink-2);font-size:1.05em}
.prose blockquote p:last-child{margin:0}
.prose a{text-decoration-color:var(--ink-4)}
.prose table{width:100%;border-collapse:collapse;margin:1.6em 0 1.8em;font-size:15px;line-height:1.5}
.prose th,.prose td{padding:11px 12px 11px 0;text-align:left;border-bottom:1px solid var(--rule);vertical-align:top}
.prose thead th{font-family:var(--mono);font-size:11px;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-3);font-weight:500;border-bottom:1px solid var(--ink)}
.prose td.r,.prose th.r{text-align:right;padding-right:0;font-family:var(--mono);font-feature-settings:"tnum"}
.prose tfoot td,.prose tfoot th{font-weight:650;border-bottom:0;border-top:1px solid var(--ink)}
.table-scroll{overflow-x:auto;-webkit-overflow-scrolling:touch}
.aside-note{background:var(--sheet);border:1px solid var(--rule);border-left:3px solid var(--ink);padding:18px 20px;margin:1.8em 0;font-size:15.5px;line-height:1.7}
.aside-note p{margin:0}
.aside-note p+p{margin-top:.7em}
.aside-note .label{display:block;margin-bottom:6px}
.formula{font-family:var(--mono);font-size:15px;background:var(--sheet);border:1px solid var(--rule);padding:16px 18px;margin:1.4em 0;line-height:1.6;overflow-x:auto}
.formula small{display:block;color:var(--ink-3);font-size:13px;margin-top:4px}

/* plates (figures) */
.plate{margin:2em 0;border:1px solid var(--ink);background:var(--sheet)}
.plate-svg{padding:clamp(12px,2.5vw,26px)}
.plate-svg svg{max-height:560px;margin:auto}
.plate figcaption{display:flex;gap:14px;align-items:baseline;border-top:1px solid var(--ink);padding:10px 14px;font-size:14px;color:var(--ink-2);line-height:1.5}
.plate figcaption .label{flex-shrink:0;color:var(--ink)}
.plate--pair{display:grid;grid-template-columns:1fr 1fr}
.plate--pair>div{border-right:1px solid var(--ink)}
.plate--pair>div:last-child{border-right:0}

/* article layout */
.article-head{padding:clamp(20px,3vw,32px) 0 clamp(28px,4vw,44px)}
.article-head .kicker{display:flex;gap:14px;align-items:center;flex-wrap:wrap}
.article-head .kicker .cat{font-size:14px;font-weight:600;color:var(--red-ink)}
.article-head h1{font-size:clamp(30px,4.4vw,54px);line-height:1.14;letter-spacing:-.04em;margin:16px 0 0;font-weight:700;max-width:20em}
html[lang=en] .article-head h1{letter-spacing:-.028em;line-height:1.1}
.article-head .dek{font-size:clamp(17px,1.6vw,20px);line-height:1.65;color:var(--ink-2);max-width:38em;margin:20px 0 0}
.byline{display:flex;gap:6px 18px;flex-wrap:wrap;margin-top:24px;font-size:13.5px;color:var(--ink-3)}
.byline span+span::before{content:"";display:inline-block;width:4px;height:4px;background:var(--ink-4);border-radius:50%;margin-right:18px;vertical-align:middle;position:relative;top:-1px}
.article-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:clamp(32px,6vw,88px);align-items:start;border-top:1px solid var(--ink);padding-top:clamp(28px,4vw,48px)}
.article-body{max-width:700px;padding-bottom:clamp(40px,6vw,80px)}
.article-body>.plate:first-child{margin-top:0}
.rail{position:sticky;top:calc(var(--header) + 24px);display:grid;gap:20px}
.spec{border:1px solid var(--ink);background:var(--sheet)}
.spec-title{padding:10px 14px;border-bottom:1px solid var(--ink);display:flex;justify-content:space-between;align-items:center}
.spec dl{margin:0;padding:4px 14px 6px}
.spec dl div{display:flex;justify-content:space-between;gap:12px;padding:8px 0;border-bottom:1px solid var(--rule-2);font-size:14px}
.spec dl div:last-child{border-bottom:0}
.spec dt{color:var(--ink-3)}
.spec dd{margin:0;font-family:var(--mono);font-size:13px;text-align:right}
.spec .verdict{font-family:var(--sans);font-size:13px;font-weight:600;padding:1px 7px;border-radius:2px}
.verdict.ok{background:var(--green-wash);color:var(--green)}
.verdict.no{background:var(--red-wash);color:var(--red-ink)}
.spec-actions{padding:12px 14px 14px;display:grid;gap:8px;border-top:1px solid var(--ink)}
.rail-links h2{margin:0 0 10px}
.rail-links ul{list-style:none;margin:0;padding:0;border-top:1px solid var(--rule)}
.rail-links li a{display:block;padding:12px 0;border-bottom:1px solid var(--rule);font-size:14.5px;line-height:1.45;text-decoration:none;color:var(--ink-2)}
.rail-links li a:hover{color:var(--ink);text-decoration:underline}
.source{margin-top:3em;padding-top:18px;border-top:1px solid var(--rule);font-size:14px;color:var(--ink-3);line-height:1.7}
.source p{margin:.3em 0 0}
.next-read{margin-top:40px;border-top:1px solid var(--ink);padding-top:20px}
.next-read a{display:block;text-decoration:none;font-size:clamp(20px,2.2vw,26px);font-weight:650;letter-spacing:-.03em;line-height:1.3;margin-top:8px}
.next-read a:hover{text-decoration:underline;text-decoration-color:var(--red)}

/* study index page */
.studies-page .study-list{margin-top:0}

/* text pages (about/method/privacy/contact) */
.doc-layout{display:grid;grid-template-columns:220px minmax(0,1fr);gap:clamp(28px,6vw,96px);padding-top:clamp(32px,5vw,64px);align-items:start}
.doc-toc{position:sticky;top:calc(var(--header) + 24px);font-size:14px}
.doc-toc ol{list-style:none;margin:12px 0 0;padding:0;border-top:1px solid var(--rule)}
.doc-toc a{display:block;padding:9px 0;border-bottom:1px solid var(--rule-2);text-decoration:none;color:var(--ink-2);line-height:1.4}
.doc-toc a:hover{color:var(--ink)}
.doc-body{max-width:700px;min-width:0}
.doc-layout>*,.article-layout>*{min-width:0}
.doc-body .table-scroll table{min-width:620px;font-size:14px}
.contact-card{border:1px solid var(--ink);background:var(--sheet);padding:22px;margin:0 0 2em}
.contact-card a{font-size:clamp(19px,2.4vw,26px);font-weight:650;letter-spacing:-.02em;word-break:break-all}

/* ---------- planner ---------- */
.planner-head{padding:clamp(28px,4vw,48px) 0 clamp(20px,3vw,32px);display:grid;grid-template-columns:minmax(0,1fr) minmax(0,.9fr);gap:12px 40px;align-items:end}
.planner-head h1{font-size:clamp(28px,3.6vw,44px);line-height:1.12;letter-spacing:-.04em;margin:12px 0 0}
html[lang=en] .planner-head h1{letter-spacing:-.025em}
.planner-head p{margin:0;color:var(--ink-2);font-size:15.5px}
.planner{display:grid;grid-template-columns:320px minmax(0,1fr);border:1px solid var(--ink);background:var(--sheet)}
.planner-side{border-right:1px solid var(--ink);display:flex;flex-direction:column}
.panel{padding:20px 20px 22px;border-bottom:1px solid var(--rule)}
.panel:last-child{border-bottom:0}
.panel-title{display:flex;align-items:baseline;gap:10px;margin:0 0 14px;font-size:15px;font-weight:650;letter-spacing:-.02em}
.panel-title .label{color:var(--red-ink)}
.field{display:grid;gap:5px;min-width:0}
.field label{font-size:12.5px;color:var(--ink-3);font-weight:500}
.field input,.field select{width:100%;height:42px;border:1px solid var(--rule);border-radius:2px;background:#fff;padding:0 11px;font-size:15px;transition:border-color .15s}
.field input{font-family:var(--mono);font-size:14.5px}
.field input:hover,.field select:hover{border-color:var(--ink-4)}
.field input:focus,.field select:focus{border-color:var(--ink);outline:none;box-shadow:0 0 0 3px var(--blue-wash)}
.field-row{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.field-row--4{grid-template-columns:repeat(4,minmax(0,1fr))}
.hint{font-size:13px;color:var(--ink-3);line-height:1.55;margin:10px 0 0}
.preset-chips{display:flex;flex-wrap:wrap;gap:6px;margin-top:14px}
.preset-chips button{border:1px solid var(--rule);background:transparent;padding:6px 10px;font-size:13px;border-radius:2px;color:var(--ink-2)}
.preset-chips button:hover{border-color:var(--ink);color:var(--ink)}
.add-row{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:8px;align-items:end}
.check{display:flex;gap:9px;align-items:center;font-size:14px;cursor:pointer}
.check input{width:17px;height:17px;accent-color:var(--ink)}
.side-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}
.btn-quiet{border:1px solid var(--rule);background:transparent;padding:7px 12px;font-size:13.5px;border-radius:2px;color:var(--ink-2)}
.btn-quiet:hover:not(:disabled){border-color:var(--ink);color:var(--ink)}
.planner-stage{display:flex;flex-direction:column;min-width:0}
.stage-head{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:12px 16px;border-bottom:1px solid var(--rule)}
.stage-head h2{margin:0;font-size:15px;font-weight:650;display:flex;gap:10px;align-items:center}
.toolbar{display:flex;gap:6px}
.floor-area{background:var(--paper);padding:clamp(10px,2.5vw,28px);display:flex;justify-content:center;touch-action:none;border-bottom:1px solid var(--rule)}
.floor-svg{width:100%;max-height:min(66vh,640px);user-select:none;-webkit-user-select:none}
.floor-svg .furniture{cursor:grab}
.floor-svg .furniture:active{cursor:grabbing}
.floor-svg .furniture:focus{outline:none}
.floor-svg .furniture:focus-visible rect:first-child{stroke:var(--blue);stroke-width:3}
.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));border-bottom:1px solid var(--rule)}
.stat{padding:14px 16px;border-right:1px solid var(--rule);min-width:0}
.stat:last-child{border-right:0}
.stat .k{font-family:var(--mono);font-size:10.5px;letter-spacing:.07em;text-transform:uppercase;color:var(--ink-3)}
.stat .v{font-family:var(--mono);font-size:clamp(20px,2.2vw,26px);font-weight:500;letter-spacing:-.03em;margin-top:4px;line-height:1.2}
.stat .v[data-state=ok]{color:var(--green)}
.stat .v[data-state=warn]{color:var(--red)}
.stat .s{font-size:12.5px;color:var(--ink-3);margin-top:2px;line-height:1.4}
.alert{margin:0;padding:12px 16px 12px 14px;font-size:14px;line-height:1.55;border-left:3px solid var(--ink-4);background:var(--paper);border-bottom:1px solid var(--rule)}
.alert.warn{border-left-color:var(--red);background:var(--red-wash);color:#5A2414}
.alert.ok{border-left-color:var(--green);background:var(--green-wash);color:#1E4634}
.inspector{padding:16px;border-bottom:1px solid var(--rule)}
.inspector-head{display:flex;justify-content:space-between;align-items:baseline;gap:10px;margin:0 0 12px;font-size:15px;font-weight:650}
.inspector-head #selected-name{color:var(--blue)}
.inspector-empty{margin:0;font-size:14px;color:var(--ink-3)}
#selection-controls:not([hidden])~.inspector-empty{display:none}
.edit-actions{display:flex;gap:6px;flex-wrap:wrap;margin-top:12px}
.stage-actions{display:flex;gap:10px;flex-wrap:wrap;padding:16px;align-items:center}
.stage-actions .mini-note{flex-basis:100%;margin:4px 0 0;font-size:13px;color:var(--ink-3);line-height:1.55}
.planner-controls-mobile{display:none}
.noscript{padding:16px;background:var(--red-wash);border:1px solid var(--red)}
.planner-faq{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:0;border-top:1px solid var(--ink);margin-top:clamp(48px,6vw,80px)}
.planner-faq>div{padding:24px 28px 8px 0;margin-right:28px;border-right:1px solid var(--rule)}
.planner-faq>div:last-child{border-right:0;margin-right:0}
.planner-faq h2{font-size:17px;margin:0 0 8px;letter-spacing:-.02em}
.planner-faq p{margin:0;font-size:15px;color:var(--ink-2)}

/* toast */
.toast{position:fixed;left:50%;bottom:24px;transform:translate(-50%,20px);background:var(--ink);color:var(--paper);padding:11px 18px;font-size:14px;border-radius:2px;opacity:0;pointer-events:none;transition:opacity .2s,transform .2s;z-index:60;max-width:calc(100% - 32px)}
.toast.show{opacity:1;transform:translate(-50%,0)}

/* gateway & 404 */
.gateway{min-height:100vh;display:grid;place-items:center;padding:40px var(--gutter)}
.gateway-box{width:min(640px,100%)}
.gateway h1{font-size:clamp(28px,5vw,44px);line-height:1.2;letter-spacing:-.03em;margin:28px 0 8px}
.gateway p{color:var(--ink-2);margin:0}
.gateway-choices{display:grid;grid-template-columns:1fr 1fr;border:1px solid var(--ink);margin-top:32px;background:var(--sheet)}
.gateway-choices a{padding:22px;text-decoration:none;display:flex;flex-direction:column;gap:6px;min-height:120px;justify-content:space-between}
.gateway-choices a+a{border-left:1px solid var(--ink)}
.gateway-choices a:hover{background:var(--ink);color:var(--paper)}
.gateway-choices strong{font-size:24px;letter-spacing:-.02em}
.gateway-choices span{font-size:14px;opacity:.75}

/* ---------- responsive ---------- */
@media (max-width:1100px){
  .study-row{grid-template-columns:44px minmax(0,1fr) 150px 80px}
  .study-thumb{display:none}
  .planner{grid-template-columns:290px minmax(0,1fr)}
  .field-row--4{grid-template-columns:1fr 1fr}
}
@media (max-width:960px){
  .header-inner{gap:14px}
  .menu-toggle{display:inline-flex;margin-left:auto;order:3}
  .lang-switch{order:2;margin-left:auto}
  .menu-toggle{margin-left:0}
  .nav{display:none;position:fixed;inset:var(--header) 0 auto 0;flex-direction:column;align-items:stretch;gap:0;background:var(--paper);border-bottom:1px solid var(--ink);padding:8px var(--gutter) 20px;margin:0;max-height:calc(100vh - var(--header));overflow:auto}
  .nav.open{display:flex}
  .nav a{padding:16px 0;border-bottom:1px solid var(--rule);font-size:18px;font-weight:600;color:var(--ink)}
  .nav a[aria-current=page]::after{display:none}
  .nav a[aria-current=page]{color:var(--red-ink)}
  .nav .nav-cta{margin-top:16px;text-align:center;padding:14px;border-bottom:0;font-size:16px}
  .hero-grid{grid-template-columns:1fr}
  .band-head{grid-template-columns:1fr;gap:14px}
  .band-head .label{padding-top:0}
  .contrast{grid-template-columns:1fr}
  .contrast-plot{border-right:0;border-bottom:1px solid var(--ink)}
  .steps{grid-template-columns:1fr}
  .steps li{border-right:0;margin-right:0;padding:24px 0;border-bottom:1px solid var(--rule)}
  .steps li:last-child{border-bottom:0}
  .cta-inner{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-about{grid-column:1/-1}
  .page-head--split{grid-template-columns:1fr;gap:20px}
  .article-layout{grid-template-columns:1fr}
  .rail{position:static;order:-1}
  .rail-links{display:none}
  .doc-layout{grid-template-columns:1fr}
  .doc-toc{position:static}
  .planner-head{grid-template-columns:1fr}
  .planner{grid-template-columns:1fr}
  .planner-side{border-right:0;border-top:1px solid var(--ink);order:2}
  .planner-stage{order:1}
  .planner-controls-mobile{display:block}
  .planner-faq{grid-template-columns:1fr}
  .planner-faq>div{border-right:0;margin-right:0;padding:22px 0;border-bottom:1px solid var(--rule)}
}
@media (max-width:640px){
  :root{--header:58px}
  body{font-size:15.5px}
  .brand-sub{display:none}
  .hero{padding-top:28px}
  .hero-facts li{padding-right:14px;margin-right:14px;font-size:13px}
  .hero-actions .btn{flex:1 1 auto}
  .titleblock{grid-template-columns:1fr 1fr}
  .titleblock div:first-child{grid-column:1/-1;border-right:0;border-bottom:1px solid var(--ink)}
  .sheet{box-shadow:5px 5px 0 var(--paper-2)}
  .study-row{grid-template-columns:32px minmax(0,1fr);gap:4px 12px;padding:18px 0}
  .study-spec{grid-column:2;font-size:12px}
  .study-time{display:none}
  .prose{font-size:16.5px}
  html[lang=en] .prose{font-size:17px}
  .plate--pair{grid-template-columns:1fr}
  .plate--pair>div{border-right:0;border-bottom:1px solid var(--ink)}
  .plate--pair>div:last-child{border-bottom:0}
  .plate figcaption{flex-direction:column;gap:2px}
  .footer-grid{grid-template-columns:1fr 1fr;gap:28px}
  .stats{grid-template-columns:1fr 1fr}
  .stat:nth-child(2){border-right:0}
  .stat:last-child{grid-column:1/-1;border-top:1px solid var(--rule)}
  .stage-head{flex-wrap:wrap}
  .stage-actions .btn{flex:1 1 100%}
  .gateway-choices{grid-template-columns:1fr}
  .gateway-choices a+a{border-left:0;border-top:1px solid var(--ink)}
  .lang-switch{font-size:12px}
  .lang-switch a{padding:4px 7px}
}
@media (max-width:380px){
  .brand-name{font-size:15.5px}
  .lang-switch a{padding:4px 5px}
  .menu-toggle .menu-label{display:none}
  .header-inner{gap:10px}
}
@media print{
  .site-header,.site-footer,.rail,.cta-band,.planner-side,.stage-actions,.toolbar{display:none!important}
  body{background:#fff}
}