/* ==========================================================================
   ค่ามาตรฐานราคากลาง — โยธาไทย · app.yotathai.com/param
   ระบบดีไซน์ออกแบบใหม่: "หนังสืออ้างอิงวิศวกรรม" — กระดาษอุ่น หมึกน้ำเงินเข้ม ไฮไลต์อำพัน
   ตัวเลขใช้ tabular-nums เสมอ · รองรับสว่าง/มืด · พิมพ์ได้ · มือถือก่อน
   ========================================================================== */

:root{
  /* หมึก */
  --ink:#0b1f3a; --ink-2:#24395a; --ink-3:#5b6b85; --ink-4:#8a97ad;
  /* กระดาษ */
  --paper:#f7f5f0; --paper-2:#ffffff; --paper-3:#efece5; --paper-4:#e7e3d9;
  --line:#e3dfd5; --line-strong:#cbc5b8;
  /* ไฮไลต์อำพัน */
  --accent:#f5a524; --accent-2:#ffd27a; --accent-ink:#7a4b00; --accent-soft:#fff4dc;
  /* สถานะความเชื่อมั่น */
  --declared:#15803d; --declared-soft:#e6f6ec;
  --derived:#1d4ed8;  --derived-soft:#e8eefc;
  --verify:#b45309;   --verify-soft:#fdf1e0;
  --danger:#b91c1c;   --danger-soft:#fdecec;
  --info:#0e7490;     --info-soft:#e3f6f9;

  --shadow-1:0 1px 2px rgba(11,31,58,.06),0 1px 1px rgba(11,31,58,.04);
  --shadow-2:0 6px 16px -6px rgba(11,31,58,.16),0 2px 6px -2px rgba(11,31,58,.08);
  --shadow-3:0 24px 48px -16px rgba(11,31,58,.22);
  --ring:0 0 0 3px rgba(245,165,36,.35);

  --r-sm:8px; --r:12px; --r-lg:18px; --r-xl:26px;
  --maxw:1120px; --gutter:clamp(16px,4vw,32px);

  --font-ui:'Bai Jamjuree','Sarabun',system-ui,-apple-system,'Segoe UI',sans-serif;
  --font-body:'Sarabun','Bai Jamjuree',system-ui,-apple-system,'Segoe UI',sans-serif;
  --font-mono:'IBM Plex Mono',ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  color-scheme:light;
}
html[data-theme="dark"]{
  color-scheme:dark;
  --ink:#e9eef7; --ink-2:#c4cee0; --ink-3:#8fa0bb; --ink-4:#6c7d99;
  --paper:#0d1421; --paper-2:#141d2e; --paper-3:#1b2740; --paper-4:#233250;
  --line:#263552; --line-strong:#34486b;
  --accent:#f7b344; --accent-2:#ffd27a; --accent-ink:#ffe1a8; --accent-soft:#2b2410;
  --declared:#4ade80; --declared-soft:#0f2a1a;
  --derived:#7aa2ff;  --derived-soft:#101f3f;
  --verify:#fbbf24;   --verify-soft:#2e2208;
  --danger:#f87171;   --danger-soft:#3a1212;
  --info:#5fd3e6;     --info-soft:#0c2a30;
  --shadow-1:0 1px 2px rgba(0,0,0,.5);
  --shadow-2:0 8px 20px -8px rgba(0,0,0,.6);
  --shadow-3:0 28px 56px -20px rgba(0,0,0,.75);
}
@media (prefers-color-scheme:dark){
  html:not([data-theme="light"]){
    color-scheme:dark;
    --ink:#e9eef7; --ink-2:#c4cee0; --ink-3:#8fa0bb; --ink-4:#6c7d99;
    --paper:#0d1421; --paper-2:#141d2e; --paper-3:#1b2740; --paper-4:#233250;
    --line:#263552; --line-strong:#34486b;
    --accent:#f7b344; --accent-2:#ffd27a; --accent-ink:#ffe1a8; --accent-soft:#2b2410;
    --declared:#4ade80; --declared-soft:#0f2a1a;
    --derived:#7aa2ff;  --derived-soft:#101f3f;
    --verify:#fbbf24;   --verify-soft:#2e2208;
    --danger:#f87171;   --danger-soft:#3a1212;
    --info:#5fd3e6;     --info-soft:#0c2a30;
    --shadow-1:0 1px 2px rgba(0,0,0,.5);
    --shadow-2:0 8px 20px -8px rgba(0,0,0,.6);
    --shadow-3:0 28px 56px -20px rgba(0,0,0,.75);
  }
}

/* ---------- base ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:84px}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}
body{
  margin:0;background:var(--paper);color:var(--ink);
  font-family:var(--font-body);font-size:17px;line-height:1.7;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
  font-variant-numeric:tabular-nums;
}
body::before{ /* พื้นผิวกระดาษจางๆ */
  content:"";position:fixed;inset:0;pointer-events:none;z-index:0;
  background:
    radial-gradient(1200px 500px at 15% -10%,rgba(245,165,36,.10),transparent 60%),
    radial-gradient(900px 400px at 110% 10%,rgba(11,31,58,.06),transparent 60%);
}
html[data-theme="dark"] body::before{
  background:
    radial-gradient(1200px 500px at 15% -10%,rgba(247,179,68,.08),transparent 60%),
    radial-gradient(900px 400px at 110% 10%,rgba(122,162,255,.07),transparent 60%);
}
h1,h2,h3,h4{font-family:var(--font-ui);line-height:1.25;margin:0 0 .5em;color:var(--ink);letter-spacing:-.01em}
h1{font-size:clamp(1.75rem,3.6vw,2.5rem);font-weight:700}
h2{font-size:clamp(1.3rem,2.4vw,1.65rem);font-weight:700}
h3{font-size:1.15rem;font-weight:600}
p{margin:0 0 1em}
a{color:var(--derived);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:3px}
code,kbd,pre{font-family:var(--font-mono)}
code{font-size:.92em;background:var(--paper-3);padding:.1em .4em;border-radius:6px}
pre{background:var(--paper-3);border:1px solid var(--line);border-radius:var(--r);padding:14px 16px;overflow:auto;font-size:.95em;line-height:1.6}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:none;box-shadow:var(--ring);border-radius:6px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 var(--gutter);position:relative;z-index:1}
.visually-hidden{position:absolute!important;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.num{font-variant-numeric:tabular-nums;font-feature-settings:"tnum" 1}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:color-mix(in srgb,var(--paper) 82%,transparent);
  backdrop-filter:saturate(1.4) blur(12px);-webkit-backdrop-filter:saturate(1.4) blur(12px);
  border-bottom:1px solid var(--line);
}
.site-header .wrap{display:flex;align-items:center;gap:12px;min-height:64px}
.brand{display:flex;align-items:center;gap:10px;color:var(--ink);font-family:var(--font-ui);font-weight:700;font-size:1.05rem;text-decoration:none!important;line-height:1.1}
.brand-mark{width:38px;height:38px;border-radius:10px;background:linear-gradient(135deg,var(--ink) 0%,var(--ink-2) 100%);display:grid;place-items:center;color:var(--accent);flex:none;box-shadow:var(--shadow-1)}
.brand-mark svg{width:22px;height:22px}
.brand small{display:block;font-weight:500;font-size:.72rem;color:var(--ink-3);letter-spacing:.02em}
.header-spacer{flex:1}
.hdr-btn{display:inline-flex;align-items:center;gap:6px;height:38px;padding:0 12px;border-radius:999px;border:1px solid var(--line);background:var(--paper-2);color:var(--ink-2);font:600 .88rem var(--font-ui);cursor:pointer;text-decoration:none!important;transition:background .15s,border-color .15s,transform .1s}
.hdr-btn:hover{background:var(--paper-3);border-color:var(--line-strong)}
.hdr-btn:active{transform:translateY(1px)}
.hdr-btn svg{width:18px;height:18px}
.hdr-btn .lbl{display:none}
@media (min-width:640px){.hdr-btn .lbl{display:inline}}
#btnTheme .moon{display:none}
html[data-theme="dark"] #btnTheme .sun{display:none}
html[data-theme="dark"] #btnTheme .moon{display:inline}

/* ---------- hero + search ---------- */
.hero{padding:clamp(28px,6vw,64px) 0 clamp(20px,4vw,36px);text-align:center}
.hero .eyebrow{display:inline-flex;align-items:center;gap:8px;font:600 .8rem var(--font-ui);letter-spacing:.08em;text-transform:uppercase;color:var(--accent-ink);background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 45%,transparent);padding:6px 12px;border-radius:999px;margin-bottom:16px}
.hero .eyebrow svg{width:15px;height:15px;flex:none}
.section-h h2 svg,.block h2 svg{flex:none}
.hero h1{margin-bottom:10px}
.hero h1 .hl{background:linear-gradient(transparent 62%,var(--accent-2) 62%);padding:0 .1em}
.hero .lead{max-width:720px;margin:0 auto 26px;color:var(--ink-2);font-size:1.08rem}
.hero .stats{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 18px;margin-top:18px;font:600 .86rem var(--font-ui);color:var(--ink-3)}
.hero .stats b{color:var(--ink);font-size:1.05rem}

.search{position:relative;max-width:760px;margin:0 auto}
.search-box{display:flex;align-items:center;gap:10px;background:var(--paper-2);border:1.5px solid var(--line-strong);border-radius:16px;padding:6px 8px 6px 16px;box-shadow:var(--shadow-2);transition:border-color .15s,box-shadow .15s}
.search-box:focus-within{border-color:var(--accent);box-shadow:var(--shadow-2),var(--ring)}
.search-box svg{width:22px;height:22px;color:var(--ink-3);flex:none}
.search-box input{flex:1;min-width:0;border:0;outline:0;background:transparent;font:500 1.12rem var(--font-body);color:var(--ink);padding:10px 0}
.search-box input::placeholder{color:var(--ink-4)}
.search-box .kbd{display:none;font:500 .72rem var(--font-mono);color:var(--ink-3);border:1px solid var(--line);border-radius:6px;padding:2px 7px;background:var(--paper-3)}
@media (min-width:640px){.search-box .kbd{display:inline-block}}
.search-box .clear{display:none;width:34px;height:34px;border-radius:10px;border:0;background:var(--paper-3);color:var(--ink-2);cursor:pointer}
.search-box.has-q .clear{display:grid;place-items:center}
.search-box .clear svg{width:16px;height:16px}

.results{position:absolute;left:0;right:0;top:calc(100% + 8px);z-index:40;background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);box-shadow:var(--shadow-3);overflow:hidden;display:none;text-align:left;max-height:min(70vh,640px);overflow-y:auto}
.results.open{display:block}
.results .meta{display:flex;justify-content:space-between;align-items:center;padding:10px 16px;font:600 .8rem var(--font-ui);color:var(--ink-3);border-bottom:1px solid var(--line);background:var(--paper-3);position:sticky;top:0}
.results .empty{padding:28px 16px;text-align:center;color:var(--ink-3)}
.results .empty b{color:var(--ink)}
.rgroup{padding:6px 0}
.rgroup+.rgroup{border-top:1px solid var(--line)}
.rgroup-h{padding:6px 16px 2px;font:700 .74rem var(--font-ui);letter-spacing:.06em;text-transform:uppercase;color:var(--ink-4)}
.ritem{display:grid;grid-template-columns:1fr auto;gap:4px 14px;align-items:center;padding:10px 16px;color:inherit;text-decoration:none!important;border-left:3px solid transparent}
.ritem:hover,.ritem[aria-selected="true"]{background:var(--paper-3);border-left-color:var(--accent)}
.ritem .t{font:600 1rem var(--font-ui);color:var(--ink);line-height:1.3}
.ritem .s{grid-column:1;font-size:.88rem;color:var(--ink-3);line-height:1.45;display:-webkit-box;-webkit-line-clamp:1;-webkit-box-orient:vertical;overflow:hidden}
.ritem .t{grid-column:1;grid-row:1}
.ritem .v{grid-column:2;grid-row:1/3;text-align:right;font:700 1.05rem var(--font-ui);color:var(--ink);white-space:nowrap}
.ritem .v small{display:block;font:500 .74rem var(--font-body);color:var(--ink-3)}
.ritem mark{background:var(--accent-2);color:inherit;padding:0 .08em;border-radius:3px}
html[data-theme="dark"] .ritem mark{background:#5c4410;color:#ffe1a8}

.chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-top:16px}
.chip{display:inline-flex;align-items:center;gap:6px;padding:7px 12px;border-radius:999px;border:1px solid var(--line);background:var(--paper-2);color:var(--ink-2);font:500 .86rem var(--font-ui);text-decoration:none!important;transition:all .15s;cursor:pointer}
.chip:hover{border-color:var(--accent);background:var(--accent-soft);color:var(--accent-ink)}
.chip.active{background:var(--ink);color:var(--paper);border-color:var(--ink)}

/* ---------- sections ---------- */
.section{padding:clamp(22px,4vw,40px) 0}
.section-h{display:flex;align-items:end;justify-content:space-between;gap:16px;margin-bottom:18px;flex-wrap:wrap}
.section-h p{margin:0;color:var(--ink-3);max-width:640px}
.section-h .more{font:600 .9rem var(--font-ui);white-space:nowrap}

.grid{display:grid;gap:14px}
.grid-cat{grid-template-columns:repeat(auto-fill,minmax(250px,1fr))}
.grid-2{grid-template-columns:repeat(auto-fill,minmax(320px,1fr))}

.cat-card{display:flex;flex-direction:column;gap:10px;background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);padding:18px;color:inherit;text-decoration:none!important;position:relative;overflow:hidden;transition:transform .15s,box-shadow .15s,border-color .15s;min-height:150px}
.cat-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-2);border-color:var(--line-strong)}
.cat-card .ic{width:44px;height:44px;border-radius:12px;display:grid;place-items:center;background:var(--accent-soft);color:var(--accent-ink);border:1px solid color-mix(in srgb,var(--accent) 35%,transparent)}
.cat-card .ic svg{width:24px;height:24px}
.cat-card h3{margin:0;font-size:1.08rem}
.cat-card p{margin:0;color:var(--ink-3);font-size:.92rem;line-height:1.5;flex:1}
.cat-card .cnt{font:700 .82rem var(--font-ui);color:var(--ink-3)}
.cat-card .cnt b{color:var(--ink);font-size:1rem}

/* ---------- entry card (list) ---------- */
.ecard{display:grid;grid-template-columns:1fr auto;gap:8px 16px;background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);padding:16px 18px;color:inherit;text-decoration:none!important;transition:transform .15s,box-shadow .15s,border-color .15s;position:relative}
.ecard:hover{transform:translateY(-1px);box-shadow:var(--shadow-2);border-color:var(--line-strong)}
.ecard .t{font:600 1.05rem var(--font-ui);line-height:1.3;color:var(--ink)}
.ecard .s{grid-column:1;color:var(--ink-3);font-size:.92rem;line-height:1.5;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.ecard .t{grid-column:1;grid-row:1}
.ecard .v{grid-column:2;grid-row:1/3;align-self:start;text-align:right;font:700 1.35rem var(--font-ui);color:var(--ink);white-space:nowrap;letter-spacing:-.01em}
.ecard .v small{display:block;font:500 .76rem var(--font-body);color:var(--ink-3);letter-spacing:0}
.ecard .foot{grid-column:1/-1;display:flex;flex-wrap:wrap;gap:6px;align-items:center;margin-top:2px}
.ecard.has-warn{border-color:color-mix(in srgb,var(--danger) 45%,var(--line))}
@media (max-width:520px){.ecard{grid-template-columns:1fr}.ecard .v{grid-column:1;grid-row:auto;text-align:left;font-size:1.25rem}.ecard .v small{display:inline;margin-left:6px}}

/* ---------- badges ---------- */
.badge{display:inline-flex;align-items:center;gap:5px;padding:3px 9px;border-radius:999px;font:700 .72rem var(--font-ui);letter-spacing:.02em;border:1px solid transparent;white-space:nowrap}
.badge svg{width:12px;height:12px}
.badge.declared{background:var(--declared-soft);color:var(--declared);border-color:color-mix(in srgb,var(--declared) 35%,transparent)}
.badge.derived{background:var(--derived-soft);color:var(--derived);border-color:color-mix(in srgb,var(--derived) 35%,transparent)}
.badge.verify{background:var(--verify-soft);color:var(--verify);border-color:color-mix(in srgb,var(--verify) 35%,transparent)}
.badge.warn{background:var(--danger-soft);color:var(--danger);border-color:color-mix(in srgb,var(--danger) 35%,transparent)}
.badge.wg{background:var(--paper-3);color:var(--ink-2);border-color:var(--line)}
.badge.cat{background:var(--paper-3);color:var(--ink-2);border-color:var(--line)}

/* ---------- entry page ---------- */
.crumbs{display:flex;flex-wrap:wrap;gap:6px;align-items:center;font:500 .86rem var(--font-ui);color:var(--ink-3);padding:16px 0 4px}
.crumbs a{color:var(--ink-3)}
.crumbs a:hover{color:var(--ink)}
.crumbs .sep{opacity:.5}
.entry-head{padding:8px 0 20px}
.entry-head .cat-line{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:12px}
.entry-head h1{max-width:900px}
.entry-head .summary{font-size:1.12rem;color:var(--ink-2);max-width:820px;margin:0}

.value-hero{display:grid;grid-template-columns:1fr auto;gap:16px;align-items:center;background:linear-gradient(135deg,var(--paper-2),var(--paper-3));border:1px solid var(--line);border-radius:var(--r-xl);padding:clamp(18px,3vw,28px);margin:6px 0 22px;box-shadow:var(--shadow-1);position:relative;overflow:hidden}
.value-hero::after{content:"";position:absolute;inset:auto -40px -60px auto;width:220px;height:220px;border-radius:50%;background:radial-gradient(circle,color-mix(in srgb,var(--accent) 22%,transparent),transparent 70%);pointer-events:none}
.value-hero .lbl{font:600 .78rem var(--font-ui);letter-spacing:.08em;text-transform:uppercase;color:var(--ink-3);margin-bottom:4px}
.value-hero .val{font:700 clamp(2.2rem,6vw,3.6rem) var(--font-ui);letter-spacing:-.02em;line-height:1.05;color:var(--ink);word-break:break-word}
.value-hero .unit{font:600 clamp(1rem,2.4vw,1.35rem) var(--font-body);color:var(--ink-2);margin-left:.35em;white-space:nowrap}
.value-hero .side{display:flex;flex-direction:column;gap:8px;align-items:flex-end;position:relative;z-index:1}
.value-hero .conf{text-align:right;font-size:.82rem;color:var(--ink-3);max-width:220px;line-height:1.4}
@media (max-width:640px){.value-hero{grid-template-columns:1fr}.value-hero .side{align-items:flex-start}.value-hero .conf{text-align:left;max-width:none}}
.value-hero.is-formula .val{font-family:var(--font-mono);font-size:clamp(1.15rem,3.2vw,1.7rem);font-weight:600;letter-spacing:0;line-height:1.4}

.entry-body{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;align-items:start}
@media (max-width:900px){.entry-body{grid-template-columns:1fr}}
.entry-main>*+*{margin-top:18px}
.block{background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);padding:18px 20px;box-shadow:var(--shadow-1)}
.block>h2{font-size:1.05rem;display:flex;align-items:center;gap:8px;margin-bottom:10px;color:var(--ink)}
.block>h2 svg{width:18px;height:18px;color:var(--ink-3)}
.block p:last-child{margin-bottom:0}
.block ol,.block ul{margin:0;padding-left:1.3em}
.block li+li{margin-top:.35em}
.block .tbl{overflow-x:auto;margin:6px -4px 0;padding:0 4px}
.block table{font-size:.95rem}
.block th{text-align:left;font:700 .82rem var(--font-ui);color:var(--ink-3);letter-spacing:.02em;border-bottom:2px solid var(--line-strong);padding:8px 10px;white-space:nowrap;background:var(--paper-3);position:sticky;top:0}
.block td{padding:8px 10px;border-bottom:1px solid var(--line);vertical-align:top}
.block tr:last-child td{border-bottom:0}
.block td.n,.block th.n{text-align:right;font-variant-numeric:tabular-nums}
.block tbody tr:hover td{background:color-mix(in srgb,var(--accent-soft) 60%,transparent)}

.callout{border-radius:var(--r-lg);padding:16px 18px 16px 52px;position:relative;border:1px solid;line-height:1.6}
.callout::before{content:"";position:absolute;left:16px;top:17px;width:24px;height:24px;background-repeat:no-repeat;background-size:24px}
.callout h2{font-size:1rem;margin-bottom:6px}
.callout p:last-child{margin-bottom:0}
.callout.warn{background:var(--danger-soft);border-color:color-mix(in srgb,var(--danger) 40%,transparent);color:var(--ink)}
.callout.warn h2{color:var(--danger)}
.callout.warn::before{background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23b91c1c' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'><path d='M10.3 3.9 1.8 18a2 2 0 0 0 1.7 3h17a2 2 0 0 0 1.7-3L13.7 3.9a2 2 0 0 0-3.4 0z'/><path d='M12 9v4M12 17h.01'/></svg>")}
.callout.info{background:var(--info-soft);border-color:color-mix(in srgb,var(--info) 40%,transparent)}
.callout.info h2{color:var(--info)}
.callout.info::before{background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%230e7490' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'><circle cx='12' cy='12' r='10'/><path d='M12 16v-4M12 8h.01'/></svg>")}
.callout.scope{background:var(--paper-3);border-color:var(--line)}
.callout.scope h2{color:var(--ink-2)}
.callout.scope::before{background-image:url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%235b6b85' stroke-width='2.2' stroke-linecap='round' stroke-linejoin='round'><path d='M3 6h18M6 12h12M9 18h6'/></svg>")}

.cite{display:grid;grid-template-columns:1fr auto;gap:12px;align-items:start;background:var(--paper-3);border:1px dashed var(--line-strong);border-radius:var(--r);padding:12px 14px}
.cite .doc{font:600 .95rem var(--font-ui);color:var(--ink)}
.cite .ref{font-size:.9rem;color:var(--ink-2);margin-top:2px}
.cite .ref code{background:var(--paper-2)}
.copy-btn{display:inline-flex;align-items:center;gap:6px;height:34px;padding:0 12px;border-radius:9px;border:1px solid var(--line-strong);background:var(--paper-2);color:var(--ink-2);font:600 .82rem var(--font-ui);cursor:pointer;white-space:nowrap;transition:all .15s}
.copy-btn:hover{border-color:var(--accent);color:var(--accent-ink);background:var(--accent-soft)}
.copy-btn svg{width:15px;height:15px}
.copy-btn.done{border-color:var(--declared);color:var(--declared);background:var(--declared-soft)}

.formula{font-family:var(--font-mono);font-size:1.02rem;line-height:1.7;background:var(--ink);color:#fff;padding:16px 18px;border-radius:var(--r);overflow:auto;white-space:pre-wrap;word-break:break-word}
html[data-theme="dark"] .formula{background:#08101c;border:1px solid var(--line)}
.vars{margin-top:12px}
.vars th:first-child,.vars td:first-child{font-family:var(--font-mono);font-weight:600;white-space:nowrap}

.steps{counter-reset:s;list-style:none;padding:0!important;margin:0}
.steps li{position:relative;padding-left:40px;margin-top:10px!important}
.steps li::before{counter-increment:s;content:counter(s);position:absolute;left:0;top:1px;width:28px;height:28px;border-radius:50%;background:var(--ink);color:var(--paper);font:700 .85rem var(--font-ui);display:grid;place-items:center}
.example{background:var(--accent-soft);border:1px solid color-mix(in srgb,var(--accent) 40%,transparent);border-radius:var(--r);padding:14px 16px;white-space:pre-wrap;font-size:.98rem;line-height:1.7}

.entry-side>*+*{margin-top:14px}
.side-block{background:var(--paper-2);border:1px solid var(--line);border-radius:var(--r-lg);padding:16px 18px}
.side-block h3{font-size:.86rem;letter-spacing:.06em;text-transform:uppercase;color:var(--ink-3);margin-bottom:10px}
.side-block .kv{display:grid;grid-template-columns:auto 1fr;gap:6px 12px;font-size:.92rem}
.side-block .kv dt{color:var(--ink-3);white-space:nowrap}
.side-block .kv dd{margin:0;color:var(--ink);font-weight:500}
.related{list-style:none;margin:0;padding:0}
.related li+li{border-top:1px solid var(--line)}
.related a{display:block;padding:9px 0;color:var(--ink);font:500 .93rem var(--font-body);line-height:1.4}
.related a:hover{color:var(--derived)}
.related a small{display:block;color:var(--ink-3);font-size:.8rem}
.kw-list{display:flex;flex-wrap:wrap;gap:6px}
.kw-list span{font-size:.8rem;padding:3px 9px;border-radius:999px;background:var(--paper-3);color:var(--ink-2);border:1px solid var(--line)}

/* ---------- category page ---------- */
.cat-head{padding:14px 0 18px;display:grid;grid-template-columns:auto 1fr;gap:16px;align-items:center}
@media (max-width:520px){.cat-head{grid-template-columns:1fr;gap:10px}}
.cat-head .ic{width:60px;height:60px;border-radius:16px;display:grid;place-items:center;background:var(--accent-soft);color:var(--accent-ink);border:1px solid color-mix(in srgb,var(--accent) 35%,transparent)}
.cat-head .ic svg{width:30px;height:30px}
.cat-head p{margin:0;color:var(--ink-2);max-width:760px}
.toolbar{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin:8px 0 18px}
.toolbar .lbl{font:600 .82rem var(--font-ui);color:var(--ink-3);margin-right:4px}
.list{display:grid;gap:12px}
.count-line{font:600 .86rem var(--font-ui);color:var(--ink-3);margin:0 0 12px}

/* ---------- highlight strip (hidden rules) ---------- */
.rule-card{background:var(--ink);color:#e9eef7;border-radius:var(--r-lg);padding:18px 20px;display:flex;flex-direction:column;gap:8px;text-decoration:none!important;position:relative;overflow:hidden;transition:transform .15s}
.rule-card:hover{transform:translateY(-2px)}
.rule-card::before{content:"";position:absolute;right:-30px;top:-30px;width:140px;height:140px;border-radius:50%;background:radial-gradient(circle,rgba(245,165,36,.35),transparent 70%)}
.rule-card .v{font:700 1.7rem var(--font-ui);color:var(--accent-2);letter-spacing:-.01em;line-height:1.1}
.rule-card .t{font:600 1rem var(--font-ui);color:#fff}
.rule-card .s{font-size:.88rem;color:#b9c6da;line-height:1.5}
html[data-theme="dark"] .rule-card{background:#1b2740;border:1px solid var(--line)}

/* ---------- ads (มาตรฐานเครือ) ---------- */
.ad-slot{margin:22px auto;max-width:var(--maxw);padding:0 var(--gutter);display:none}
.ad-slot.filled{display:block}
.ad-slot .ad-label{display:none;font:500 .7rem var(--font-ui);color:var(--ink-4);text-align:center;margin-bottom:4px;letter-spacing:.06em}
.ad-slot.filled .ad-label{display:block}

/* ---------- footer ---------- */
.site-footer{margin-top:clamp(32px,6vw,64px);border-top:1px solid var(--line);background:var(--paper-3);padding:32px 0 40px;color:var(--ink-3);font-size:.9rem}
.site-footer .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:20px}
.site-footer h4{font-size:.82rem;letter-spacing:.06em;text-transform:uppercase;color:var(--ink-2);margin-bottom:8px}
.site-footer ul{list-style:none;margin:0;padding:0}
.site-footer li+li{margin-top:4px}
.site-footer a{color:var(--ink-2)}
.site-footer .disc{margin-top:22px;padding-top:16px;border-top:1px solid var(--line);font-size:.84rem;line-height:1.6}
.site-footer .disc b{color:var(--ink-2)}

/* ---------- utilities ---------- */
.muted{color:var(--ink-3)}
.mt-0{margin-top:0!important}
.hide{display:none!important}
.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%) translateY(20px);background:var(--ink);color:var(--paper);padding:10px 16px;border-radius:999px;font:600 .88rem var(--font-ui);box-shadow:var(--shadow-3);opacity:0;pointer-events:none;transition:all .2s;z-index:80}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* ---------- print ---------- */
@media print{
  body{background:#fff;color:#000;font-size:12pt}
  body::before,.site-header,.site-footer,.ad-slot,.search,.chips,.copy-btn,.entry-side .side-block.no-print,.toast{display:none!important}
  .wrap{max-width:none;padding:0}
  .block,.callout,.value-hero,.cite{box-shadow:none;border-color:#999;break-inside:avoid}
  .value-hero::after{display:none}
  .formula{background:#111;color:#fff;-webkit-print-color-adjust:exact;print-color-adjust:exact}
  .entry-body{grid-template-columns:1fr}
  a{color:#000;text-decoration:none}
  .cite{border-style:solid}
  .print-src{display:block!important;margin-top:16px;font-size:10pt;color:#333}
}
.print-src{display:none}