/* Layout: forest-green header + textured hero band, tool card lifted over the band, content column below */
:root{
  --bg:#f4f7f3;color-scheme:light;--panel:#ffffff;--ink:#1f2a22;--muted:#5b6a5f;--line:#d9e0d8;
  --brand:#24412b;--brand-2:#2f5a39;--sand:#e0b65a;--sand-ink:#3a2d10;
  --accent:#2f6b3c;--accent-soft:#e3efe2;--shadow:0 10px 30px rgba(20,40,25,.12);
  --font:system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.65 var(--font)}
a{color:var(--accent)}
.wrap{max-width:1000px;margin:0 auto;padding-left:max(16px,env(safe-area-inset-left));padding-right:max(16px,env(safe-area-inset-right))}

/* Header */
header.site{background:var(--brand);color:#fff}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;padding-block:12px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;text-decoration:none;line-height:1.1}
.brand .mark{width:38px;height:38px;flex:none}
.brand b{display:block;font-size:20px;font-weight:800;letter-spacing:-.2px}
.brand b em{font-style:normal;color:var(--sand)}
.brand small{display:block;font-size:11px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:var(--sand)}
nav.main{display:flex;gap:6px;flex-wrap:wrap}
nav.main a{color:#dfe9e1;text-decoration:none;font-size:15px;padding:6px 12px;border-radius:999px}
nav.main a:hover{background:rgba(255,255,255,.1);color:#fff}
nav.main a[aria-current]{background:var(--sand);color:var(--sand-ink);font-weight:700}

/* Hero band */
.hero{background:linear-gradient(180deg,var(--brand-2),var(--brand));color:#fff;position:relative;overflow:hidden;padding-block:28px 96px}
.hero .wrap{position:relative}
.hero h1{font-size:clamp(30px,5vw,46px);line-height:1.1;margin:0 0 10px;text-wrap:balance}
.hero p{margin:0;max-width:62ch;color:#dbe8de;font-size:17px}
.crumbs{font-size:13px;color:#cfe0d3;margin-bottom:8px}
.crumbs a{color:#cfe0d3}
.badges{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}
.badges span{font-size:13px;background:rgba(255,255,255,.12);border:1px solid rgba(255,255,255,.18);padding:4px 10px;border-radius:999px}

main{padding-bottom:56px}
.lift{margin-top:-72px;position:relative}
.plain{padding-top:28px}

/* Tool */
.tool{background:var(--panel);border-radius:16px;box-shadow:var(--shadow);padding:22px;display:grid;grid-template-columns:1.1fr 1fr;gap:22px}
@media (max-width:760px){.tool{grid-template-columns:1fr;padding:16px}}
.fields{display:grid;gap:12px;align-content:start}
.row{display:grid;grid-template-columns:1fr 1fr;gap:12px}
label{display:block;font-size:13px;font-weight:600;color:var(--muted);margin-bottom:4px}
input,select{width:100%;font:inherit;font-size:16px;padding:10px 12px;border:1px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink)}
input:focus,select:focus{outline:2px solid var(--accent);outline-offset:1px}
.unit{display:flex;gap:6px}.unit input{flex:1;min-width:0}.unit select{width:auto}
.results{background:linear-gradient(160deg,var(--accent-soft),var(--panel));border:1px solid var(--line);border-radius:12px;padding:16px;display:grid;gap:12px;align-content:start}
.results .k{font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
.big{font-size:44px;font-weight:800;line-height:1;font-variant-numeric:tabular-nums;color:var(--accent)}
.big small{font-size:18px;font-weight:700;color:var(--muted)}
.res-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.res{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:10px 12px}
.res b{display:block;font-size:20px;font-variant-numeric:tabular-nums}
.res span{font-size:13px;color:var(--muted)}
.note{font-size:13px;color:var(--muted);margin:0}

/* Feature strip */
.features{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:20px 0 8px}
@media (max-width:640px){.features{grid-template-columns:1fr}}
.feature{display:flex;gap:10px;align-items:flex-start;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:12px}
.feature svg{width:28px;height:28px;flex:none;color:var(--accent)}
.feature b{display:block;font-size:15px}
.feature span{font-size:13px;color:var(--muted)}

/* Content */
.content{max-width:760px;background:var(--panel);border:1px solid var(--line);border-radius:16px;padding:8px 28px 28px;margin-top:24px}
@media (max-width:640px){.content{padding:4px 16px 20px}}
.content h2:first-child{margin-top:24px}
h2{font-size:26px;line-height:1.25;margin:44px 0 10px;text-wrap:balance}
h3{font-size:18px;margin:24px 0 6px}
.tbl{overflow-x:auto;margin:12px 0;background:var(--panel);border:1px solid var(--line);border-radius:12px}
table{border-collapse:collapse;width:100%;font-size:15px}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line)}
tr:last-child td{border-bottom:0}
th{font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);background:var(--bg)}
td.n{font-variant-numeric:tabular-nums}
.types{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:12px;margin:12px 0}
.type{background:var(--panel);border:1px solid var(--line);border-radius:12px;overflow:hidden}
.type img{display:block;width:100%;height:auto;aspect-ratio:700/196;object-fit:cover}
.type div{padding:10px 12px}
.type b{display:block}
.type span{font-size:14px;color:var(--muted)}
figure.diagram{margin:16px 0;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:12px}
figure.diagram svg{display:block;width:100%;height:auto}
figure.diagram figcaption{font-size:13px;color:var(--muted);margin-top:6px}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin-top:12px}
.card{display:flex;flex-direction:column;gap:0;align-items:stretch;padding:0 !important;overflow:hidden;background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:14px;text-decoration:none;color:var(--ink);transition:transform .15s}
.card:hover{transform:translateY(-2px);border-color:var(--accent)}
.card img{width:100%;height:150px;object-fit:cover;display:block}
.card div{padding:12px 14px 14px}
.card b{display:block;color:var(--accent)}
.card span{font-size:14px;color:var(--muted)}
details{background:var(--panel);border:1px solid var(--line);border-radius:10px;padding:12px 14px;margin:8px 0}
summary{font-weight:600;cursor:pointer}
details p{margin:8px 0 0}

footer.site{background:var(--brand);color:#cfdcd2;padding-block:28px;font-size:14px}
footer.site .wrap{display:flex;gap:16px;flex-wrap:wrap;justify-content:space-between;align-items:center}
footer.site a{color:#cfdcd2}
footer.site .brand b{font-size:16px}
@media (prefers-reduced-motion:reduce){.card{transition:none}}
.stack{display:grid;gap:14px;margin:16px 0}
.srow{display:grid;grid-template-columns:1fr 1fr;gap:16px;align-items:center;background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:14px}
.srow img{width:100%;height:170px;object-fit:cover;border-radius:10px;display:block}
.stxt{display:flex;gap:12px;align-items:flex-start}
.snum{flex:none;width:34px;height:34px;border-radius:50%;background:var(--brand);color:#fff;font-weight:800;display:grid;place-items:center}
.stxt small{font-size:12px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:var(--muted)}
.stxt h3{margin:2px 0 4px;font-size:20px}
.stxt p{margin:0;font-size:15px}
.stxt .sdepth{display:inline-block;background:var(--accent-soft);color:var(--accent);font-weight:700;font-size:13px;padding:2px 10px;border-radius:999px;margin-bottom:6px}
@media (max-width:640px){.srow{grid-template-columns:1fr}.srow img{height:150px}}
.copy{font:inherit;font-weight:700;font-size:14px;background:var(--brand);color:#fff;border:0;border-radius:10px;padding:10px 14px;cursor:pointer}
.copy:hover{background:var(--accent)}
.copy:focus-visible{outline:2px solid var(--sand);outline-offset:2px}
.toc{background:var(--bg);border:1px solid var(--line);border-radius:12px;padding:12px 16px;margin-top:20px}
.toc b{font-size:13px;letter-spacing:.08em;text-transform:uppercase;color:var(--muted)}
.toc ol{margin:6px 0 0;padding-left:20px;columns:2;column-gap:24px;font-size:15px}
@media (max-width:640px){.toc ol{columns:1}}
.toc a{text-decoration:none}
.updated{margin-top:24px}
h2[id]{scroll-margin-top:16px}

.tool[data-tool=gravel] .res-grid{grid-template-columns:repeat(3,1fr);gap:8px}
@media (max-width:420px){.tool[data-tool=gravel] .res-grid{grid-template-columns:1fr 1fr}}
.res{padding:8px 10px}.res b{font-size:18px}.res span{font-size:12px}
.results{gap:10px}
.copy{padding:8px 12px;justify-self:start}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chips button{font:inherit;font-size:14px;border:1px solid var(--line);background:var(--bg);color:var(--ink);border-radius:999px;padding:7px 12px;cursor:pointer}
.chips button:hover,.chips button.on{border-color:var(--accent);background:var(--accent-soft);color:var(--accent);font-weight:600}
.tool[data-tool=gravel] .res-grid .res:last-child{grid-column:1/-1;display:flex;align-items:baseline;gap:10px}