/* ====================================================
   JIUM LABS — base styles
   ==================================================== */
:root {
  --bg: #FAFAF9;
  --bg-elev: #FFFFFF;
  --bg-sunken: #F4F4F2;
  --fg: #18181B;
  --fg-muted: #6B6B72;
  --fg-subtle: #9A9AA2;
  --border: #E7E6E2;
  --border-strong: #D8D7D2;
  --accent: oklch(0.55 0.15 260);
  --accent-soft: oklch(0.55 0.15 260 / 0.10);
  --accent-fg: #FFFFFF;
  --radius-sm: 6px;
  --radius: 10px;
  --radius-lg: 16px;
  --radius-xl: 22px;
  --shadow-sm: 0 1px 0 rgba(20,20,30,.04), 0 1px 2px rgba(20,20,30,.04);
  --shadow: 0 1px 0 rgba(20,20,30,.04), 0 8px 24px -8px rgba(20,20,30,.08);
  --container: 1200px;
  --gutter: 24px;
  --section-y: 112px;
  --font-sans: "Pretendard Variable", Pretendard, ui-sans-serif, system-ui, -apple-system, "Helvetica Neue", Arial, "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}
[data-theme="dark"] {
  --bg: #0E0E10;
  --bg-elev: #161618;
  --bg-sunken: #0A0A0C;
  --fg: #F4F4F5;
  --fg-muted: #A1A1A8;
  --fg-subtle: #6E6E76;
  --border: #232327;
  --border-strong: #303036;
  --shadow-sm: 0 1px 0 rgba(0,0,0,.4);
  --shadow: 0 1px 0 rgba(0,0,0,.4), 0 8px 28px -8px rgba(0,0,0,.6);
}
[data-accent="indigo"]  { --accent: oklch(0.55 0.15 260); --accent-soft: oklch(0.55 0.15 260 / 0.10); }
[data-accent="emerald"] { --accent: oklch(0.58 0.13 158); --accent-soft: oklch(0.58 0.13 158 / 0.10); }
[data-accent="amber"]   { --accent: oklch(0.70 0.15 70);  --accent-soft: oklch(0.70 0.15 70 / 0.12); --accent-fg:#1a1306; }
[data-accent="rose"]    { --accent: oklch(0.62 0.16 18);  --accent-soft: oklch(0.62 0.16 18 / 0.10); }
[data-accent="ink"]     { --accent: var(--fg); --accent-soft: color-mix(in oklab, var(--fg) 8%, transparent); --accent-fg: var(--bg); }

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; text-decoration: none; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 16px; background: var(--fg); color: var(--bg); padding: 8px 12px; border-radius: 6px; z-index: 100; }

.container { max-width: var(--container); margin: 0 auto; padding: 0 var(--gutter); }
.mono { font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.02em; text-transform: uppercase; color: var(--fg-muted); }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; padding: 6px 10px 6px 8px; border: 1px solid var(--border); border-radius: 999px; font-family: var(--font-mono); font-size: 11.5px; letter-spacing: 0.06em; text-transform: uppercase; color: var(--fg-muted); background: var(--bg-elev); }
.eyebrow::before { content: ""; width: 6px; height: 6px; border-radius: 999px; background: var(--accent); display: inline-block; }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 6px; height: 40px; padding: 0 16px; border-radius: 8px; font: inherit; font-weight: 500; font-size: 14px; cursor: pointer; border: 1px solid transparent; transition: background .15s, border-color .15s, color .15s, transform .05s; }
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--fg); color: var(--bg); }
.btn--primary:hover { background: color-mix(in oklab, var(--fg) 88%, var(--bg)); }
.btn--accent { background: var(--accent); color: var(--accent-fg); }
.btn--accent:hover { background: color-mix(in oklab, var(--accent) 88%, black); }
.btn--ghost { background: transparent; color: var(--fg); }
.btn--ghost:hover { background: var(--bg-sunken); }
.btn--outline { background: transparent; color: var(--fg); border-color: var(--border-strong); }
.btn--outline:hover { background: var(--bg-sunken); }
.btn--lg { height: 48px; padding: 0 20px; font-size: 15px; }

/* NAV */
.nav { position: sticky; top: 0; z-index: 50; background: color-mix(in oklab, var(--bg) 84%, transparent); backdrop-filter: saturate(140%) blur(10px); border-bottom: 1px solid var(--border); }
.nav__inner { display: flex; align-items: center; gap: 32px; height: 64px; }
.brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 600; letter-spacing: -0.01em; }
.brand__mark { display: inline-flex; align-items: center; justify-content: center; width: 28px; height: 28px; border-radius: 7px; background: var(--fg); color: var(--bg); }
.brand__name { font-size: 15px; letter-spacing: 0.04em; }
.nav__links { display: flex; gap: 26px; margin-left: 8px; }
.nav__links a { font-size: 14px; color: var(--fg-muted); }
.nav__links a:hover { color: var(--fg); }
.nav__actions { margin-left: auto; display: flex; gap: 8px; align-items: center; }
@media (max-width: 880px) { .nav__links { display: none; } }

/* SECTION */
.section { padding: var(--section-y) 0; border-top: 1px solid var(--border); }
.section--flush { border-top: 0; }
.section__head { display: flex; flex-direction: column; gap: 16px; max-width: 720px; margin-bottom: 56px; }
.section__head h2 { margin: 0; font-size: clamp(28px, 3vw, 40px); line-height: 1.12; letter-spacing: -0.02em; font-weight: 600; }
.section__head p { margin: 0; color: var(--fg-muted); font-size: 17px; line-height: 1.55; max-width: 60ch; }

/* FOOTER */
.footer { border-top: 1px solid var(--border); background: var(--bg-sunken); padding: 72px 0 56px; }
.footer__inner { display: grid; grid-template-columns: 1.4fr 2fr; gap: 56px; }
.footer__tag { color: var(--fg-muted); margin: 18px 0 24px; line-height: 1.55; max-width: 36ch; }
.footer__legal { font-family: var(--font-mono); font-size: 11.5px; color: var(--fg-subtle); letter-spacing: 0.04em; }
.footer__cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.footer__cols h4 { font-size: 12px; font-family: var(--font-mono); font-weight: 500; letter-spacing: 0.08em; text-transform: uppercase; color: var(--fg-subtle); margin: 0 0 14px; }
.footer__cols a { display: block; font-size: 14px; color: var(--fg); padding: 6px 0; }
.footer__cols a:hover { color: var(--accent); }
@media (max-width: 880px) { .footer__inner { grid-template-columns: 1fr; gap: 40px; } .footer__cols { grid-template-columns: repeat(2, 1fr); } }