/* Starc Solutions — site stylesheet
   System: 12 × 78 + 24 inside 1200; bar 104; type 60/38/32/24/20/16/15/14/13.5/12/11 mono.
   Rules: full-bleed only at the two page boundaries; content rules are 1200 wide. */

*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scrollbar-width:none}
html::-webkit-scrollbar{width:0;height:0}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:Inter,'Noto Sans SC','Noto Sans TC','Noto Sans JP','Noto Sans KR',system-ui,sans-serif;
  font-size:16px;line-height:1.62;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility;
}
img{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4,p,ul,ol,figure,blockquote{margin:0}
ul,ol{padding:0;list-style:none}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
table{border-collapse:collapse;width:100%}
::selection{background:var(--accent);color:#fff}

:root{
  --bg:#FFFFFF; --ink:#101112; --muted:#6D7074; --line:#E4E4E1; --panel:#F6F6F3;
  --accent:#05A99C; --accent-ink:#FFFFFF; --deep:#0B4F47;
  --ease:cubic-bezier(.2,.7,.2,1); --dur:240ms; --slow:520ms;
}

/* ---------- grid ---------- */
.wrap{width:1200px;margin:0 auto}
.cols{display:grid;grid-template-columns:repeat(12,78px);column-gap:24px}

/* ---------- type ---------- */
.eyebrow{font-family:'Google Sans Code',ui-monospace,monospace;font-size:11px;line-height:1.4;
  letter-spacing:.14em;text-transform:uppercase;color:var(--accent)}
.display{font-size:60px;line-height:1.04;letter-spacing:-.03em;font-weight:600}
.display,.h1,.h2,.h3,.h4{margin:0}
.h1{font-size:38px;line-height:1.1;letter-spacing:-.025em;font-weight:600}
.h2{font-size:32px;line-height:1.15;letter-spacing:-.02em;font-weight:600}
.h3{font-size:24px;line-height:1.25;letter-spacing:-.02em;font-weight:600}
.h4{font-size:20px;line-height:1.3;letter-spacing:-.01em;font-weight:600}
.lede{font-size:17px;line-height:1.6;color:var(--muted)}
.body{font-size:16px;line-height:1.62}
.small{font-size:14px;line-height:1.65}
.tiny{font-size:13px;line-height:1.6}
.mono{font-family:'Google Sans Code',ui-monospace,monospace;font-size:11px;letter-spacing:.08em}
.label{font-family:'Google Sans Code',ui-monospace,monospace;font-size:11px;letter-spacing:.12em;
  text-transform:uppercase;color:var(--muted)}
.muted{color:var(--muted)}

/* ---------- chrome ---------- */
.nav{position:sticky;top:0;z-index:50;height:104px;border-bottom:1px solid var(--line);
  background:rgba(255,255,255,.86);backdrop-filter:saturate(160%) blur(10px);
  transition:height var(--dur) var(--ease),box-shadow var(--dur) var(--ease)}
.nav.scrolled{height:84px;box-shadow:0 1px 0 rgba(16,17,18,.04),0 12px 24px -24px rgba(16,17,18,.4)}
.navin{height:100%;display:grid;grid-template-columns:auto 1fr auto;align-items:center}
.brand{display:flex;align-items:center;flex:0 0 auto}
.brand img{height:61px;width:auto;flex:0 0 auto;transition:height var(--dur) var(--ease)}
.nav.scrolled .brand img{height:52px}
.links{display:flex;gap:30px;margin-left:48px;margin-right:24px;font-size:14px;min-width:0}
.links a{position:relative;padding:6px 0;color:var(--ink);opacity:.85;white-space:nowrap;transition:opacity var(--dur) var(--ease)}
.links a::after{content:"";position:absolute;left:0;right:0;bottom:0;height:1px;background:var(--ink);
  transform:scaleX(0);transform-origin:left;transition:transform var(--dur) var(--ease)}
.links a:hover{opacity:1}
.links a:hover::after,.links a[aria-current]::after{transform:scaleX(1)}
.act{display:flex;align-items:center;gap:28px}
.signin{font-size:14px;color:var(--muted);transition:color var(--dur) var(--ease)}
.signin:hover{color:var(--ink)}

.btn{display:inline-flex;align-items:center;justify-content:center;height:44px;padding:0 22px;
  background:var(--accent);color:var(--accent-ink);font-size:14px;font-weight:600;line-height:1;
  border:1px solid var(--accent);transition:background var(--dur) var(--ease),color var(--dur) var(--ease),
  border-color var(--dur) var(--ease),transform var(--dur) var(--ease)}
.btn:hover{background:var(--deep);border-color:var(--deep);transform:translateY(-1px)}
.btn-lg{height:48px;padding:0 26px;font-size:14.5px}
.btn-ghost{display:inline-flex;align-items:center;justify-content:center;height:44px;padding:0 22px;
  border:1px solid var(--line);font-size:14px;font-weight:500;line-height:1;
  transition:border-color var(--dur) var(--ease),transform var(--dur) var(--ease)}
.btn-ghost:hover{border-color:var(--ink);transform:translateY(-1px)}
.btn-lg.btn-ghost{height:48px;padding:0 26px;font-size:14.5px}

.footer{padding:56px 0 28px;border-top:1px solid var(--line)}
.footer .top{display:grid;grid-template-columns:1fr 3fr;column-gap:24px}
.footer .mark img{height:64px;width:auto}
.footer .cols3{display:grid;grid-template-columns:repeat(3,1fr);column-gap:24px}
.footer .cols3 div{display:flex;flex-direction:column;gap:10px;font-size:13.5px;color:var(--muted)}
.footer .cols3 .h{font-family:'Google Sans Code',ui-monospace,monospace;font-size:11px;letter-spacing:.12em;
  text-transform:uppercase;color:var(--ink);margin-bottom:2px}
.footer .cols3 a{transition:color var(--dur) var(--ease)}
.footer .cols3 a:hover{color:var(--ink)}
.footer .base{display:flex;justify-content:space-between;margin-top:40px;padding-top:16px;
  border-top:1px solid var(--line);font-size:12px;color:var(--muted)}

/* ---------- atoms ---------- */
.tag{display:inline-flex;align-items:center;height:26px;padding:0 10px;border:1px solid var(--line);
  font-size:12px;line-height:1;transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease)}
.tag:hover{border-color:var(--ink)}
.tags{display:flex;flex-wrap:wrap;gap:8px}
.frame{border:1px solid var(--line);background:#fff;padding:14px;transition:border-color var(--dur) var(--ease)}
.frame img{width:100%;height:auto;border:0}
.frame .cap{display:flex;justify-content:space-between;gap:16px;padding:12px 2px 0;
  font-family:'Google Sans Code',ui-monospace,monospace;font-size:10.5px;letter-spacing:.06em;color:var(--muted)}
.eq{overflow:visible}
.katex{font-size:1.02em}
.katex-display{margin:0}

/* ---------- structure ---------- */
.rule-top{border-top:1px solid var(--line)}
.sec{margin:64px 0}
.sec-tight{margin:48px 0}
.split{margin-top:48px}
.split{padding-top:0}
.split > .wrap{border-top:1px solid var(--line);padding-top:64px}

/* ---------- motion ---------- */
[data-reveal]{opacity:0;transform:translateY(16px);
  transition:opacity var(--slow) var(--ease),transform var(--slow) var(--ease);
  transition-delay:calc(var(--i,0) * 70ms);will-change:opacity,transform}
[data-reveal].in{opacity:1;transform:none}
[data-reveal="fade"]{transform:none}
[data-reveal="clip"]{opacity:1;transform:none;clip-path:inset(0 0 100% 0);
  transition:clip-path 720ms var(--ease);transition-delay:calc(var(--i,0) * 70ms)}
[data-reveal="clip"].in{clip-path:inset(0 0 0 0)}

@keyframes caret{0%,49%{opacity:1}50%,100%{opacity:0}}
.caret{display:inline-block;width:1px;height:1em;background:var(--ink);vertical-align:-2px;
  margin-left:2px;animation:caret 1.05s steps(1) infinite}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.001ms !important;animation-iteration-count:1 !important;
    transition-duration:.001ms !important}
  [data-reveal]{opacity:1;transform:none;clip-path:none}
}