/* ============================================================
   BASE — Variables, Reset, Typography, Layout
   ============================================================ */

:root {
  /* Background layers */
  --bg-0: #080808;
  --bg-1: #0f0f0f;
  --bg-2: #161616;
  --bg-3: #1e1e1e;

  /* Borders */
  --border-subtle: #161616;
  --border: #242424;
  --border-hover: #333333;

  /* Text */
  --text-0: #f0f0f0;
  --text-1: #909090;
  --text-2: #555555;

  /* Accent — Indigo */
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --accent-dim: rgba(99, 102, 241, 0.12);
  --accent-glow: rgba(99, 102, 241, 0.28);

  /* Typography */
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;

  /* Layout */
  --nav-height: 64px;
  --max-width: 1160px;
  --max-width-narrow: 720px;
  --max-width-xs: 480px;

  /* Border-radius */
  --r-xs:   4px;
  --r-sm:   6px;
  --r-md:   10px;
  --r-lg:   14px;
  --r-xl:   20px;
  --r-full: 9999px;

  /* Shadows */
  --shadow-sm:     0 1px 3px rgba(0,0,0,0.5);
  --shadow-md:     0 4px 20px rgba(0,0,0,0.4);
  --shadow-lg:     0 12px 48px rgba(0,0,0,0.5);
  --shadow-accent: 0 0 32px var(--accent-glow);

  /* Easing */
  --ease:     cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in:  cubic-bezier(0.4, 0, 1, 1);
}

/* ── Reset ─────────────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg-0);
  color: var(--text-0);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
  min-height: 100vh;
}

::selection {
  background: var(--accent-dim);
  color: var(--text-0);
}

::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: var(--bg-0); }
::-webkit-scrollbar-thumb { background: var(--bg-3); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--border-hover); }

/* ── Typography ─────────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-0);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.03em;
}

h1 { font-size: clamp(38px, 6.5vw, 80px); }
h2 { font-size: clamp(28px, 4.5vw, 56px); }
h3 { font-size: clamp(20px, 2.5vw, 30px); }
h4 { font-size: clamp(16px, 1.8vw, 20px); font-weight: 600; letter-spacing: -0.02em; }
h5 { font-size: 16px; font-weight: 600; letter-spacing: -0.01em; }
h6 { font-size: 14px; font-weight: 600; letter-spacing: 0; }

p {
  color: var(--text-1);
  line-height: 1.75;
  font-size: 16px;
}

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

ul, ol { list-style: none; }

img { max-width: 100%; height: auto; display: block; }

button { cursor: pointer; font-family: var(--font); border: none; background: none; }

input, textarea, select { font-family: var(--font); }

/* ── Layout ─────────────────────────────────────────────────── */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

@media (min-width: 768px)  { .container { padding: 0 48px; } }
@media (min-width: 1280px) { .container { padding: 0 40px; } }

.section        { padding: 128px 0; }
.section--sm    { padding: 80px 0; }
.section--xs    { padding: 56px 0; }

@media (max-width: 768px) {
  .section      { padding: 80px 0; }
  .section--sm  { padding: 64px 0; }
  .section--xs  { padding: 40px 0; }
}

/* ── Utilities ──────────────────────────────────────────────── */
.text-accent  { color: var(--accent); }
.text-muted   { color: var(--text-1); }
.text-dim     { color: var(--text-2); }
.text-center  { text-align: center; }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

hr.divider {
  border: none;
  height: 1px;
  background: var(--border-subtle);
}