/* ─────────────────────────────────────────────────────────────
   Sharingan site — terminal-noir, crimson eye.
   Display: Space Grotesk · Body: IBM Plex Sans · Mono: JetBrains Mono
   ───────────────────────────────────────────────────────────── */

:root {
  --bg: #0b0a09;
  --bg-raised: #14110f;
  --bg-panel: #181411;
  --line: #2a241f;
  --line-soft: #1f1a16;
  --ink: #ede9e3;
  --ink-dim: #a39a8f;
  --ink-faint: #6e665c;
  --crimson: #e23b3b;
  --crimson-bright: #ff5249;
  --crimson-dim: #8f2424;
  --ok: #4cc38a;
  --warn: #e5a13b;
  --info: #62a0ea;
  --mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --display: "Space Grotesk", system-ui, sans-serif;
  --body: "IBM Plex Sans", system-ui, sans-serif;
  --maxw: 1080px;
}

/* warm-paper light theme — cohesive with the terminal-noir dark default */
:root[data-theme="light"] {
  --bg: #f5f1ea;
  --bg-raised: #fffdf8;
  --bg-panel: #efe8dd;
  --line: #dbd3c5;
  --line-soft: #e7e0d3;
  --ink: #1c1815;
  --ink-dim: #5b544b;
  --ink-faint: #8c8377;
  --crimson: #d12e2e;
  --crimson-bright: #be1f1f;
  --crimson-dim: #e3aaaa;
  --ok: #1a8f57;
  --warn: #9a6712;
  --info: #2c66b3;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* grain overlay */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 2000;
  opacity: 0.5;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.04 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}
/* the dark grain is too heavy on paper — lighten it */
:root[data-theme="light"] body::before { opacity: 0.22; }

::selection { background: var(--crimson-dim); color: var(--ink); }

a { color: inherit; text-decoration: none; }

/* ── nav ─────────────────────────────────────────────────── */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--line-soft);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(12px);
}
.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  height: 58px;
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-brand {
  font-family: var(--mono);
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  letter-spacing: 0.04em;
  color: var(--ink);
}
.nav-brand .eye { width: 20px; height: 20px; }
.nav-links {
  font-family: var(--mono);
  display: flex;
  gap: 22px;
  margin-left: auto;
  font-size: 13px;
  color: var(--ink-dim);
}
.nav-links a { transition: color 0.15s; }
.nav-links a:hover, .nav-links a.active { color: var(--crimson-bright); }
.nav-gh {
  border: 1px solid var(--line);
  padding: 5px 14px;
  border-radius: 4px;
  color: var(--ink);
  transition: border-color 0.15s, color 0.15s;
}
.nav-gh:hover { border-color: var(--crimson); color: var(--crimson-bright); }
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 28px;
  padding: 0;
  background: none;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--ink-dim);
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}
.theme-toggle:hover { color: var(--crimson-bright); border-color: var(--crimson); }
.theme-toggle svg {
  width: 15px;
  height: 15px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.theme-toggle .ic-moon { display: none; }
:root[data-theme="light"] .theme-toggle .ic-sun { display: none; }
:root[data-theme="light"] .theme-toggle .ic-moon { display: inline; }

/* ── shared bits ─────────────────────────────────────────── */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.kicker {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--crimson-bright);
}
.kicker::before { content: "// "; color: var(--ink-faint); }

h2.display {
  font-family: var(--display);
  font-weight: 600;
  font-size: clamp(30px, 4.6vw, 44px);
  line-height: 1.12;
  letter-spacing: -0.01em;
  margin: 14px 0 18px;
}
h2.display em { color: var(--crimson-bright); font-style: italic; }

.lede { color: var(--ink-dim); max-width: 640px; }

code { font-family: var(--mono); }

.codeblock {
  background: var(--bg-raised);
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
  font-size: 13.5px;
}
.codeblock .cb-head {
  font-family: var(--mono);
  display: flex;
  align-items: center;
  padding: 8px 14px;
  border-bottom: 1px solid var(--line-soft);
  color: var(--ink-faint);
  font-size: 11.5px;
  letter-spacing: 0.08em;
}
.codeblock .cb-head .dots { display: flex; gap: 5px; margin-right: 12px; }
.codeblock .cb-head .dots i {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--line); display: block;
}
.codeblock .cb-head .dots i:first-child { background: var(--crimson-dim); }
.codeblock pre {
  padding: 16px 18px;
  overflow-x: auto;
  line-height: 1.7;
}
.cb-copy {
  margin-left: auto;
  background: none;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--ink-faint);
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 0.08em;
  padding: 3px 9px;
  cursor: pointer;
  transition: color .15s, border-color .15s;
}
.cb-copy:hover { color: var(--crimson-bright); border-color: var(--crimson); }

/* syntax tints */
.k { color: var(--crimson-bright); }            /* keyword */
.f { color: var(--info); }                      /* function/type */
.s { color: var(--ok); }                        /* string */
.c { color: var(--ink-faint); font-style: italic; } /* comment */
.n { color: var(--warn); }                      /* number/const */

/* ── buttons ─────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--mono);
  font-size: 13.5px;
  letter-spacing: 0.04em;
  padding: 11px 22px;
  border-radius: 5px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform .15s, box-shadow .15s, border-color .15s, background .15s;
}
.btn-primary {
  background: var(--crimson);
  color: #fff;
  box-shadow: 0 0 0 0 rgba(226, 59, 59, 0.35);
}
.btn-primary:hover {
  background: var(--crimson-bright);
  transform: translateY(-1px);
  box-shadow: 0 6px 24px -6px rgba(226, 59, 59, 0.55);
}
.btn-ghost {
  border-color: var(--line);
  color: var(--ink-dim);
}
.btn-ghost:hover { border-color: var(--crimson); color: var(--ink); }

/* ── footer ──────────────────────────────────────────────── */
footer {
  font-family: var(--mono);
  border-top: 1px solid var(--line-soft);
  margin-top: 110px;
  padding: 44px 0 60px;
  color: var(--ink-faint);
  font-size: 12.5px;
}
footer .wrap { display: flex; flex-wrap: wrap; gap: 18px; align-items: center; }
footer a { color: var(--ink-dim); }
footer a:hover { color: var(--crimson-bright); }
footer .spacer { flex: 1; }

/* ── reveal animation ────────────────────────────────────── */
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(18px);
    animation: rise 0.7s cubic-bezier(0.2, 0.7, 0.2, 1) forwards;
  }
  .reveal.d1 { animation-delay: 0.08s; }
  .reveal.d2 { animation-delay: 0.16s; }
  .reveal.d3 { animation-delay: 0.26s; }
  .reveal.d4 { animation-delay: 0.38s; }
  @keyframes rise { to { opacity: 1; transform: none; } }
}

@media (max-width: 720px) {
  .nav-links { gap: 14px; }
  .nav-links a.hide-sm { display: none; }
}