/* ============================================================
   SizeCast — product site + docs design system
   Deep-ink identity · #4D7DFF accent · clean geometric sans
   Shared by the overview page, guide, FAQ, privacy, changelog.
   ============================================================ */
:root{
  --ink-0:#0B0E1C; --ink-1:#0E1226; --ink-2:#141a33; --ink-3:#1b2140;
  --panel:#161d38; --panel-2:#1b2342; --elev:#212a4d;
  --tx:#F4F6FF; --tx-2:rgba(244,246,255,.70); --tx-3:rgba(244,246,255,.48);
  --accent:#4D7DFF; --accent-2:#6C9BFF; --accent-soft:rgba(77,125,255,.14);
  --accent-line:rgba(120,158,255,.36);
  --ok:#2FB877; --ok-soft:rgba(47,184,119,.14);
  --line:rgba(255,255,255,.09); --line-2:rgba(255,255,255,.15);
  --paper:#fff; --paper-ink:#141414; --paper-2:#5a6478;
  --disp:"SF Pro Display",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --mono:ui-monospace,"SF Mono",SFMono-Regular,Menlo,Consolas,monospace;
  --gut:clamp(1.15rem,4.2vw,3.5rem); --maxw:1200px; --readw:72ch;
  --e:cubic-bezier(.4,0,.2,1); --d1:.16s; --d2:.32s;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%;overflow-x:clip}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{margin:0;color:var(--tx);font-family:var(--sans);font-size:16.5px;line-height:1.62;font-weight:400;
  -webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;overflow-x:clip;letter-spacing:.005em;
  background:radial-gradient(120% 80% at 82% -5%,rgba(77,125,255,.16),transparent 52%),
             linear-gradient(168deg,#1A2140 0%,#131731 46%,#0B0E1C 100%);
  background-attachment:fixed;min-height:100vh}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:3px}
::selection{background:var(--accent);color:#fff}
h1,h2,h3,h4{font-family:var(--disp);font-weight:800;line-height:1.06;letter-spacing:-.02em;margin:0}
p{margin:0 0 1rem}
.mono{font-family:var(--mono)}
hr{border:0;border-top:1px solid var(--line);margin:0}

/* ---------- atoms ---------- */
.wrap{max-width:var(--maxw);margin:0 auto;padding-inline:var(--gut)}
.eyebrow{font-family:var(--mono);font-size:12px;font-weight:600;letter-spacing:.16em;text-transform:uppercase;color:var(--accent-2);
  display:inline-flex;align-items:center;gap:.6em}
.eyebrow::before{content:"";width:26px;height:3px;border-radius:2px;background:var(--accent)}
.btn{display:inline-flex;align-items:center;gap:.55em;font-family:var(--sans);font-size:.94rem;font-weight:600;
  padding:.85em 1.5em;border-radius:11px;border:1px solid var(--line-2);color:var(--tx);cursor:pointer;
  background:rgba(255,255,255,.03);transition:background var(--d1) var(--e),border-color var(--d1) var(--e),transform var(--d1) var(--e)}
.btn:hover{border-color:var(--tx-2);transform:translateY(-1px)}
.btn--solid{background:var(--accent);border-color:var(--accent);color:#fff;box-shadow:0 12px 30px -10px rgba(77,125,255,.6)}
.btn--solid:hover{background:var(--accent-2);border-color:var(--accent-2)}
.btn .ar{transition:transform var(--d1) var(--e)}
.btn:hover .ar{transform:translateX(3px)}
.badge{display:inline-flex;align-items:center;gap:.5em;font-family:var(--mono);font-size:11px;font-weight:600;letter-spacing:.06em;
  text-transform:uppercase;padding:.4em .8em;border-radius:999px;background:var(--accent-soft);border:1px solid var(--accent-line);color:var(--accent-2)}
.badge .dot{width:6px;height:6px;border-radius:50%;background:var(--accent-2)}
.card{background:rgba(255,255,255,.028);border:1px solid var(--line);border-radius:18px;padding:1.6rem}
.card--glow{box-shadow:0 0 90px rgba(77,125,255,.10)}

/* ---------- nav ---------- */
.nav{position:sticky;top:0;z-index:200;height:66px;display:flex;align-items:center;gap:1rem;
  padding-inline:var(--gut);border-bottom:1px solid transparent;transition:background var(--d2),border-color var(--d2),backdrop-filter var(--d2)}
.nav.solid{background:color-mix(in srgb,#0B0E1C 74%,transparent);backdrop-filter:saturate(160%) blur(16px);border-bottom-color:var(--line)}
.nav .brand{display:flex;align-items:center;gap:.6rem;font-family:var(--disp);font-weight:800;font-size:1.16rem;letter-spacing:-.02em}
.nav .brand img{width:30px;height:30px;border-radius:8px}
.nav .sp{flex:1}
.nav .links{display:flex;align-items:center;gap:.2rem}
.nav .links a{font-size:.9rem;font-weight:500;color:var(--tx-2);padding:.5rem .85rem;border-radius:8px}
.nav .links a:hover,.nav .links a.on{color:var(--tx);background:rgba(255,255,255,.05)}
.nav .burger{display:none;width:42px;height:42px;border:1px solid var(--line-2);border-radius:10px;background:rgba(255,255,255,.03);color:var(--tx);cursor:pointer;align-items:center;justify-content:center}
.nav .burger svg{width:18px;height:18px}
@media(max-width:840px){
  .nav .links{position:fixed;top:66px;left:0;right:0;flex-direction:column;align-items:stretch;gap:0;
    background:#0d1122;border-bottom:1px solid var(--line);padding:.5rem var(--gut) 1.1rem;transform:translateY(-140%);
    transition:transform var(--d2) var(--e);z-index:-1}
  .nav .links.open{transform:none}
  .nav .links a{padding:.9rem .3rem;border-bottom:1px solid var(--line)}
  .nav .links .btn{margin-top:.7rem;justify-content:center}
  .nav .desk-btn{display:none}
  .nav .burger{display:flex}
}

/* ---------- hero ---------- */
.hero{position:relative;padding:clamp(3.5rem,9vw,7rem) 0 clamp(2.5rem,6vw,4.5rem)}
.hero__glow{position:absolute;top:-10%;right:-5%;width:640px;height:640px;border-radius:50%;pointer-events:none;
  background:radial-gradient(circle,rgba(77,125,255,.22),transparent 62%)}
.hero h1{font-size:clamp(2.5rem,1.4rem + 5.4vw,5rem);letter-spacing:-.03em;margin:1rem 0 0;max-width:15ch}
.hero h1 em{font-style:normal;color:var(--accent-2)}
.hero__sub{max-width:54ch;font-size:clamp(1.08rem,1rem + .6vw,1.35rem);color:var(--tx-2);margin:1.4rem 0 0;line-height:1.5}
.hero__cta{display:flex;flex-wrap:wrap;gap:.7rem;margin-top:2rem}
.hero__stats{display:flex;flex-wrap:wrap;gap:2.4rem;margin-top:clamp(2.2rem,5vw,3.4rem)}
.hero__stats .n{font-family:var(--disp);font-weight:800;font-size:1.7rem;letter-spacing:-.02em;display:block}
.hero__stats .l{font-size:.85rem;color:var(--tx-3);margin-top:.15rem}

/* ---------- sections ---------- */
.sec{padding-block:clamp(3rem,7vw,5.5rem)}
.sec-head{max-width:60ch;margin-bottom:clamp(1.8rem,4vw,2.8rem)}
.sec-head h2{font-size:clamp(1.7rem,1.1rem + 2.4vw,2.7rem);margin:.6rem 0 .7rem}
.lead{font-size:clamp(1.02rem,.98rem + .4vw,1.18rem);color:var(--tx-2);line-height:1.55;max-width:58ch}

.grid{display:grid;gap:1rem}
.grid--3{grid-template-columns:repeat(3,1fr)}
.grid--2{grid-template-columns:repeat(2,1fr)}
@media(max-width:900px){.grid--3{grid-template-columns:1fr 1fr}}
@media(max-width:620px){.grid--3,.grid--2{grid-template-columns:1fr}}
.feat h3{font-size:1.14rem;margin:0 0 .4rem}
.feat p{color:var(--tx-2);font-size:.97rem;margin:0}
.feat__ic{width:44px;height:44px;border-radius:11px;background:var(--accent-soft);border:1px solid var(--accent-line);
  display:flex;align-items:center;justify-content:center;margin-bottom:1rem;color:var(--accent-2)}
.feat__ic svg{width:22px;height:22px}

/* steps */
.steps{counter-reset:s;display:grid;gap:1rem}
.step{display:flex;gap:1.2rem;align-items:flex-start;padding:1.4rem 1.5rem;background:rgba(255,255,255,.028);
  border:1px solid var(--line);border-radius:16px}
.step::before{counter-increment:s;content:counter(s);flex:0 0 auto;width:38px;height:38px;border-radius:10px;
  background:var(--accent);color:#fff;font-family:var(--disp);font-weight:800;display:flex;align-items:center;justify-content:center;font-size:1.05rem}
.step h3{font-size:1.1rem;margin:.35rem 0 .35rem}
.step p{color:var(--tx-2);margin:0;font-size:.97rem}

/* pricing */
.plans{display:grid;grid-template-columns:1fr 1fr;gap:1.1rem;max-width:820px}
@media(max-width:620px){.plans{grid-template-columns:1fr}}
.plan{background:rgba(255,255,255,.028);border:1px solid var(--line);border-radius:20px;padding:1.9rem}
.plan.hi{border-color:var(--accent-line);background:linear-gradient(180deg,var(--accent-soft),rgba(255,255,255,.02))}
.plan h3{font-size:1.3rem;margin:0}
.plan .price{font-family:var(--disp);font-weight:800;font-size:2.4rem;letter-spacing:-.02em;margin:.5rem 0 .1rem}
.plan .price small{font-size:1rem;font-weight:600;color:var(--tx-3)}
.plan ul{list-style:none;padding:0;margin:1.2rem 0 0;display:grid;gap:.6rem}
.plan li{display:flex;gap:.6rem;font-size:.96rem;color:var(--tx-2)}
.plan li svg{flex:0 0 auto;width:19px;height:19px;color:var(--accent-2);margin-top:.15em}

/* ---------- doc / prose pages ---------- */
.doc{padding:clamp(2rem,5vw,3.5rem) 0 5rem}
.doc__head{max-width:var(--readw);margin-bottom:2.4rem}
.doc__head h1{font-size:clamp(2rem,1.4rem + 3vw,3.2rem);margin:.8rem 0 .6rem}
.doc__meta{font-family:var(--mono);font-size:12px;letter-spacing:.06em;color:var(--tx-3);text-transform:uppercase}
.prose{max-width:var(--readw)}
.prose h2{font-size:clamp(1.35rem,1.1rem + 1.1vw,1.75rem);margin:2.6rem 0 .9rem;scroll-margin-top:84px}
.prose h3{font-size:1.16rem;margin:1.8rem 0 .6rem}
.prose p,.prose li{color:var(--tx-2);line-height:1.68}
.prose ul,.prose ol{padding-left:1.3rem;margin:0 0 1.1rem}
.prose li{margin:.35rem 0}
.prose strong{color:var(--tx);font-weight:600}
.prose a{color:var(--accent-2);text-decoration:underline;text-underline-offset:2px;text-decoration-thickness:1px}
.prose code{font-family:var(--mono);font-size:.88em;background:rgba(255,255,255,.06);border:1px solid var(--line);
  padding:.12em .45em;border-radius:5px;color:var(--accent-2)}
.callout{background:var(--accent-soft);border:1px solid var(--accent-line);border-radius:14px;padding:1.1rem 1.3rem;margin:1.4rem 0}
.callout p:last-child{margin:0}
.callout strong{color:var(--accent-2)}

/* FAQ */
.faq{max-width:var(--readw);display:grid;gap:.7rem}
.qa{background:rgba(255,255,255,.028);border:1px solid var(--line);border-radius:14px;overflow:hidden}
.qa summary{list-style:none;cursor:pointer;padding:1.15rem 1.4rem;font-family:var(--disp);font-weight:700;font-size:1.06rem;
  display:flex;align-items:center;justify-content:space-between;gap:1rem}
.qa summary::-webkit-details-marker{display:none}
.qa summary .pm{flex:0 0 auto;width:22px;height:22px;position:relative;transition:transform var(--d2) var(--e)}
.qa summary .pm::before,.qa summary .pm::after{content:"";position:absolute;background:var(--accent-2);border-radius:2px}
.qa summary .pm::before{top:10px;left:3px;right:3px;height:2px}
.qa summary .pm::after{left:10px;top:3px;bottom:3px;width:2px;transition:opacity var(--d1)}
.qa[open] summary .pm::after{opacity:0}
.qa__body{padding:0 1.4rem 1.3rem;color:var(--tx-2)}
.qa__body p:last-child{margin:0}

/* changelog */
.log{max-width:var(--readw);display:grid;gap:1.6rem}
.rel{border-left:2px solid var(--line-2);padding-left:1.5rem;position:relative}
.rel::before{content:"";position:absolute;left:-7px;top:4px;width:12px;height:12px;border-radius:50%;background:var(--accent);border:2px solid #0B0E1C}
.rel h3{font-size:1.2rem;display:flex;align-items:center;gap:.7rem}
.rel .ver{font-family:var(--mono);font-size:12px;color:var(--tx-3)}
.rel ul{list-style:none;padding:0;margin:.7rem 0 0;display:grid;gap:.45rem}
.rel li{display:flex;gap:.6rem;color:var(--tx-2);font-size:.97rem}
.rel li::before{content:"";flex:0 0 auto;width:6px;height:6px;border-radius:50%;background:var(--accent-2);margin-top:.6em}

/* ---------- footer ---------- */
.foot{border-top:1px solid var(--line);padding-block:2.6rem;margin-top:2rem}
.foot__row{display:flex;flex-wrap:wrap;gap:1.4rem;align-items:center;justify-content:space-between}
.foot__brand{display:flex;align-items:center;gap:.6rem;font-family:var(--disp);font-weight:800}
.foot__brand img{width:26px;height:26px;border-radius:7px}
.foot__links{display:flex;flex-wrap:wrap;gap:.3rem 1.3rem}
.foot__links a{color:var(--tx-3);font-size:.9rem}
.foot__links a:hover{color:var(--tx)}
.foot__fine{color:var(--tx-3);font-size:.85rem;margin-top:1.4rem}
.foot__fine a{color:var(--tx-2);text-decoration:underline;text-underline-offset:2px}