/* Hisab — "Midnight Amber" design system. Dark-first, amber accent.
   Sibling of SizeMint v2's Midnight Ultraviolet; own accent, own voice. */

@font-face{
  font-family:"Space Grotesk";font-style:normal;font-weight:500;font-display:swap;
  src:url("fonts/space-grotesk-latin-500-normal.woff2") format("woff2");
}
@font-face{
  font-family:"Space Grotesk";font-style:normal;font-weight:700;font-display:swap;
  src:url("fonts/space-grotesk-latin-700-normal.woff2") format("woff2");
}
@font-face{
  font-family:"Inter";font-style:normal;font-weight:400;font-display:swap;
  src:url("fonts/inter-latin-400-normal.woff2") format("woff2");
}
@font-face{
  font-family:"Inter";font-style:normal;font-weight:500;font-display:swap;
  src:url("fonts/inter-latin-500-normal.woff2") format("woff2");
}
@font-face{
  font-family:"Inter";font-style:normal;font-weight:600;font-display:swap;
  src:url("fonts/inter-latin-600-normal.woff2") format("woff2");
}

:root{
  --bg:#0c0c11;
  --bg-2:#101018;
  --card:rgba(255,255,255,.045);
  --card-solid:#14141c;
  --ink:#f5f1e8;
  --ink-soft:#d8d2c2;
  --muted:#a09a89;
  --line:rgba(255,255,255,.09);
  --line-soft:rgba(255,255,255,.055);
  --amber:#f5b942;
  --amber-deep:#e08a1e;
  --amber-ink:#201303;
  --amber-soft:rgba(245,185,66,.12);
  --grad:linear-gradient(120deg,#f5b942,#ff8c42);
  --radius:18px;
  --shadow:0 24px 70px rgba(0,0,0,.42);
  --shadow-sm:0 10px 30px rgba(0,0,0,.3);
  --font-display:"Space Grotesk","Inter",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-body:"Inter",system-ui,-apple-system,"Segoe UI",sans-serif;
}
[data-theme="light"]{
  --bg:#faf6ec;
  --bg-2:#f3edde;
  --card:rgba(255,255,255,.75);
  --card-solid:#fffdf7;
  --ink:#1c1508;
  --ink-soft:#3d3423;
  --muted:#6f6656;
  --line:rgba(28,21,8,.12);
  --line-soft:rgba(28,21,8,.07);
  --amber:#b97a12;
  --amber-deep:#d18a1b;
  --amber-ink:#fff8e8;
  --amber-soft:rgba(185,122,18,.12);
  --grad:linear-gradient(120deg,#d99a22,#e07b2a);
  --shadow:0 24px 70px rgba(60,42,8,.14);
  --shadow-sm:0 10px 30px rgba(60,42,8,.1);
}

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:var(--font-body);font-size:16px;line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
body::before{ /* ambient amber glow */
  content:"";position:fixed;inset:0;pointer-events:none;z-index:0;
  background:
    radial-gradient(640px 420px at 12% -4%,rgba(245,185,66,.09),transparent 60%),
    radial-gradient(760px 520px at 96% 8%,rgba(255,140,66,.06),transparent 60%);
}
[data-theme="light"] body::before{
  background:
    radial-gradient(640px 420px at 12% -4%,rgba(185,122,18,.08),transparent 60%),
    radial-gradient(760px 520px at 96% 8%,rgba(224,123,42,.06),transparent 60%);
}
main,header.site-header,footer.site-footer{position:relative;z-index:1}
img,svg{max-width:100%}
a{color:inherit}
::selection{background:var(--amber);color:var(--amber-ink)}

.container{width:min(1120px,92vw);margin:0 auto}
.narrow{width:min(760px,92vw);margin:0 auto}

h1,h2,h3{font-family:var(--font-display);line-height:1.12;letter-spacing:-.01em;margin:0 0 .5em}
h1{font-size:clamp(2.4rem,5.4vw,4rem);font-weight:700}
h2{font-size:clamp(1.5rem,3vw,2.1rem);font-weight:700}
h3{font-size:1.15rem;font-weight:500}
p{margin:0 0 1em;color:var(--ink-soft)}
.grad-text{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.eyebrow{
  display:flex;align-items:center;gap:.6em;
  font-size:.78rem;font-weight:600;letter-spacing:.22em;text-transform:uppercase;
  color:var(--muted);margin:0 0 1.1em;
}
.eyebrow::before{content:"";width:26px;height:2px;background:var(--grad);border-radius:2px}
.page-lead{font-size:1.12rem;max-width:60ch}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:50;
  background:color-mix(in srgb,var(--bg) 82%,transparent);
  -webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
  border-bottom:1px solid var(--line-soft);
}
.nav-wrap{display:flex;align-items:center;gap:1.4rem;padding:.85rem 0}
.brand{display:flex;align-items:center;gap:.6rem;text-decoration:none;font-family:var(--font-display);font-weight:700;font-size:1.3rem}
.logo-mark{
  display:grid;place-items:center;width:36px;height:36px;border-radius:11px;
  background:var(--grad);color:#fff;font-weight:700;font-size:1.15rem;
  box-shadow:0 6px 18px rgba(245,185,66,.35);
}
.nav{display:flex;gap:1.1rem;margin-left:auto}
.nav a{text-decoration:none;color:var(--muted);font-weight:500;font-size:.95rem;padding:.35rem .1rem;border-bottom:2px solid transparent}
.nav a:hover{color:var(--ink)}
.nav a[aria-current="page"]{color:var(--ink);border-bottom-color:var(--amber)}
.theme-toggle{
  display:flex;align-items:center;gap:.45rem;cursor:pointer;
  background:var(--card);border:1px solid var(--line);color:var(--ink);
  border-radius:999px;padding:.42rem .85rem;font-size:.85rem;font-weight:600;font-family:var(--font-body);
}
.theme-toggle:hover{border-color:var(--amber)}

/* ---------- hero ---------- */
.hero{padding:4.2rem 0 2.6rem}
.hero-grid{display:grid;gap:2.2rem;align-items:center}
@media(min-width:900px){.hero-grid{grid-template-columns:1.25fr .9fr}}
.hero-copy{font-size:1.1rem;max-width:52ch}
.hero-badges{display:flex;flex-wrap:wrap;gap:.6rem;margin-top:1.4rem;list-style:none;padding:0}
.hero-badges li{
  border:1px solid var(--line);border-radius:999px;padding:.4rem .9rem;
  font-size:.85rem;color:var(--ink-soft);background:var(--card);
}
.hero-card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:1.6rem;box-shadow:var(--shadow);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.stat-row{display:flex;justify-content:space-between;align-items:baseline;gap:1rem;padding:.7rem 0;border-bottom:1px dashed var(--line-soft)}
.stat-row:last-child{border-bottom:0}
.stat-row span{color:var(--muted);font-size:.92rem}
.stat-row strong{font-family:var(--font-display);font-size:1.25rem;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}

/* ---------- calculator grid (homepage) ---------- */
.calc-grid-home{display:grid;gap:1rem;margin:2.4rem 0}
@media(min-width:640px){.calc-grid-home{grid-template-columns:repeat(2,1fr)}}
@media(min-width:960px){.calc-grid-home{grid-template-columns:repeat(3,1fr)}}
.tool-card{
  display:block;text-decoration:none;background:var(--card);
  border:1px solid var(--line);border-radius:var(--radius);padding:1.4rem;
  transition:transform .25s ease,border-color .25s ease,box-shadow .25s ease;
}
.tool-card:hover{transform:translateY(-4px);border-color:var(--amber);box-shadow:var(--shadow-sm)}
.tool-card h3{margin:.7rem 0 .3rem;font-size:1.15rem}
.tool-card p{font-size:.92rem;margin:0;color:var(--muted)}
.tool-glyph{
  display:grid;place-items:center;width:46px;height:46px;border-radius:14px;
  background:var(--amber-soft);color:var(--amber);font-size:1.35rem;font-weight:700;
  font-family:var(--font-display);
}

/* ---------- calculator workspace ---------- */
.workspace{display:grid;gap:1.2rem;margin:2rem 0 3rem}
@media(min-width:900px){.workspace{grid-template-columns:1fr 1fr;align-items:start}}
.calc-form{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:1.6rem;box-shadow:var(--shadow-sm);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.field{margin-bottom:1.15rem}
.field label{display:block;font-weight:600;font-size:.92rem;margin-bottom:.4rem}
.field .hint{display:block;font-weight:400;font-size:.8rem;color:var(--muted);margin-top:.3rem}
.field input,.field select{
  width:100%;padding:.75rem .9rem;font-size:1rem;font-family:var(--font-body);
  color:var(--ink);background:var(--bg-2);border:1px solid var(--line);
  border-radius:12px;outline:none;
}
.field input:focus,.field select:focus{border-color:var(--amber);box-shadow:0 0 0 3px var(--amber-soft)}
.field-row{display:grid;grid-template-columns:1fr 1fr;gap:.9rem}
.results{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:1.6rem;box-shadow:var(--shadow);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.result-hero{margin-bottom:1.1rem}
.result-hero span{display:block;font-size:.85rem;color:var(--muted);letter-spacing:.08em;text-transform:uppercase;margin-bottom:.25rem}
.result-hero strong{font-family:var(--font-display);font-size:clamp(2rem,4.6vw,2.9rem);font-weight:700;background:var(--grad);-webkit-background-clip:text;background-clip:text;color:transparent}
.result-rows{display:grid;gap:0}
.result-rows>div{display:flex;justify-content:space-between;align-items:baseline;gap:1rem;padding:.65rem 0;border-top:1px dashed var(--line-soft)}
.result-rows dt{color:var(--muted);font-size:.92rem}
.result-rows dd{margin:0;font-weight:600;font-family:var(--font-display);font-size:1.05rem;text-align:right}
.result-note{font-size:.82rem;color:var(--muted);margin:.9rem 0 0}

/* ---------- content sections ---------- */
.section{padding:2.6rem 0}
.explain p{max-width:68ch}
.faq details{
  background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:1rem 1.2rem;margin-bottom:.7rem;
}
.faq summary{cursor:pointer;font-weight:600;font-family:var(--font-display);font-size:1.02rem;list-style:none;display:flex;justify-content:space-between;align-items:center;gap:1rem}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";color:var(--amber);font-size:1.4rem;font-weight:700;flex:none}
.faq details[open] summary::after{content:"–"}
.faq details p{margin:.7rem 0 0;color:var(--ink-soft)}
.qa-block{margin:1.6rem 0}
.qa-block h3{color:var(--amber);margin-bottom:.3rem}
.related{display:flex;flex-wrap:wrap;gap:.6rem;margin:2rem 0}
.related a{
  text-decoration:none;border:1px solid var(--line);border-radius:999px;
  padding:.45rem 1rem;font-size:.88rem;color:var(--ink-soft);background:var(--card);
}
.related a:hover{border-color:var(--amber);color:var(--ink)}
.maker-notes{
  border-left:3px solid var(--amber);padding:.4rem 0 .4rem 1.2rem;margin:1.8rem 0;
}
.maker-notes p strong{color:var(--ink)}

/* ---------- footer ---------- */
.site-footer{border-top:1px solid var(--line-soft);margin-top:3rem;padding:2.4rem 0 2rem}
.foot-grid{display:grid;gap:1.6rem}
@media(min-width:800px){.foot-grid{grid-template-columns:1.2fr 2fr}}
.foot-links{display:grid;grid-template-columns:repeat(2,1fr);gap:.4rem 1.2rem;list-style:none;margin:0;padding:0}
.foot-links a{text-decoration:none;color:var(--muted);font-size:.9rem}
.foot-links a:hover{color:var(--amber)}
.disclaimer{font-size:.8rem;color:var(--muted);margin-top:1.2rem;max-width:70ch}
.copyright{font-size:.82rem;color:var(--muted);margin-top:.6rem}

.btn{
  display:inline-block;text-decoration:none;cursor:pointer;border:0;
  background:var(--grad);color:#fff;font-weight:700;font-family:var(--font-display);
  padding:.85rem 1.7rem;border-radius:14px;font-size:1rem;
  box-shadow:0 10px 26px rgba(245,185,66,.32);transition:transform .2s ease;
}
.btn:hover{transform:translateY(-2px)}
.text-center{text-align:center}
.mt{margin-top:2rem}

@media(max-width:640px){
  .nav{display:none}
  .field-row{grid-template-columns:1fr}
  .hero{padding:2.8rem 0 1.8rem}
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{transition:none!important;scroll-behavior:auto!important}
}