/* khosrowan theme — dark/light, responsive, refined */
:root {
  --font-sans: "Vazirmatn", "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI",
    Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --font-mono: "Vazirmatn", "JetBrains Mono", "SFMono-Regular", "SF Mono", Menlo,
    Consolas, "Liberation Mono", monospace;
  --container: 1180px;
  --container-narrow: 740px;
  --radius-sm: 8px;
  --radius: 14px;
  --radius-lg: 22px;
  --radius-xl: 30px;
  --space-2xs: 0.5rem;
  --space-xs: 0.75rem;
  --space-s: 1rem;
  --space-m: 1.5rem;
  --space-l: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4.5rem;
  --header-h: 68px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);

  /* Dark theme (default) */
  --bg: #0b0f14;
  --bg-elevated: #121820;
  --bg-elevated-2: #1a2330;
  --text: #e8eef5;
  --text-muted: #93a0b0;
  --text-faint: #6b7886;
  --border: #1f2937;
  --accent: #38bdf8;
  --accent-2: #a78bfa;
  --accent-soft: rgba(56, 189, 248, 0.12);
  --accent-2-soft: rgba(167, 139, 250, 0.12);
  --hero-glow: rgba(56, 189, 248, 0.14);
  --card-shadow: 0 8px 30px rgba(0, 0, 0, 0.25);
}

html[data-theme="light"] {
  --bg: #f7f9fc;
  --bg-elevated: #ffffff;
  --bg-elevated-2: #f0f4f9;
  --text: #16202c;
  --text-muted: #4b5a6b;
  --text-faint: #7c8a99;
  --border: #e2e8f0;
  --accent: #0284c7;
  --accent-2: #7c3aed;
  --accent-soft: rgba(2, 132, 199, 0.1);
  --accent-2-soft: rgba(124, 58, 237, 0.09);
  --hero-glow: rgba(2, 132, 199, 0.08);
  --card-shadow: 0 6px 24px rgba(15, 23, 42, 0.07);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
  font-size: 1.075rem;
  transition: background 0.35s ease, color 0.35s ease;
}

a { color: var(--accent); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: var(--accent-2); }

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

.container { max-width: var(--container); margin: 0 auto; padding: 0 var(--space-m); }
.container.narrow { max-width: var(--container-narrow); }

/* ── Header ─────────────────────────────────────────────────────────── */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(1.4) blur(12px);
  -webkit-backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid var(--border);
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}
.site-header.scrolled { box-shadow: 0 6px 24px rgba(0, 0, 0, 0.18); }

.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: var(--header-h); gap: var(--space-m);
}

.brand { display: flex; align-items: center; gap: var(--space-xs); color: var(--text); font-weight: 800; font-size: 1.1rem; }
.brand:hover { color: var(--text); text-decoration: none; }
.brand-mark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 38px; height: 38px; border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-weight: 800; font-size: 1.1rem;
  box-shadow: 0 4px 14px var(--hero-glow);
}

.nav { display: flex; align-items: center; gap: var(--space-l); }
.nav a { color: var(--text-muted); font-weight: 500; position: relative; padding: 4px 0; }
.nav a:hover { color: var(--text); text-decoration: none; }
.nav a::after {
  content: ""; position: absolute; left: 0; right: 100%; bottom: 0;
  height: 2px; background: linear-gradient(90deg, var(--accent), var(--accent-2));
  border-radius: 2px; transition: right 0.25s var(--ease);
}
.nav a:hover::after { right: 0; }

.nav-toggle {
  display: none; background: none; border: 1px solid var(--border);
  border-radius: 10px; width: 42px; height: 42px; cursor: pointer;
  align-items: center; justify-content: center; color: var(--text);
}
.nav-toggle span { display: block; width: 18px; height: 2px; background: currentColor; border-radius: 2px; transition: transform 0.25s var(--ease), opacity 0.2s ease; }
.nav-toggle span + span { margin-top: 5px; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.theme-toggle {
  background: var(--bg-elevated-2); border: 1px solid var(--border);
  border-radius: 10px; width: 40px; height: 40px; cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--text); font-size: 1.05rem; transition: all 0.2s ease;
}
.theme-toggle:hover { border-color: var(--accent); }

/* ── Hero ───────────────────────────────────────────────────────────── */
.hero {
  padding: var(--space-2xl) 0 var(--space-xl);
  position: relative;
  background:
    radial-gradient(60% 55% at 78% 20%, var(--hero-glow), transparent 70%),
    radial-gradient(50% 45% at 12% 75%, var(--accent-2-soft), transparent 65%);
}
.hero-grid { display: grid; grid-template-columns: 1.5fr 0.85fr; gap: var(--space-xl); align-items: center; }
.hero .eyebrow { margin-bottom: var(--space-xs); }
.hero-title { font-size: clamp(2rem, 4.5vw, 3.25rem); line-height: 1.25; margin: 0 0 var(--space-s); font-weight: 800; letter-spacing: -0.01em; }
.hero-lede { color: var(--text-muted); font-size: 1.15rem; max-width: 56ch; margin: 0 0 var(--space-m); }
.hero-cta { display: flex; gap: var(--space-s); flex-wrap: wrap; margin-bottom: var(--space-m); }
.hero-note { color: var(--accent); font-weight: 500; }

.hero-visual {
  display: flex; justify-content: center;
}
.avatar-wrap {
  width: 220px; height: 220px; border-radius: 30px; overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
  background: var(--bg-elevated);
}
.avatar-wrap img { width: 100%; height: 100%; object-fit: cover; display: block; }

.rotator { color: transparent; background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; }
.rotator .word { display: inline-block; animation: word-in 0.5s var(--ease); }
@keyframes word-in { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* ── Buttons ────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex; align-items: center; gap: var(--space-2xs);
  border-radius: 12px; padding: 0.65rem 1.4rem; font-weight: 600;
  font-size: 0.98rem; border: 1px solid transparent; cursor: pointer;
  transition: all 0.22s var(--ease); white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; box-shadow: 0 8px 22px var(--hero-glow);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 28px var(--hero-glow); color: #fff; }
.btn-ghost { border-color: var(--border); color: var(--text); background: transparent; }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }

/* ── Sections ───────────────────────────────────────────────────────── */
.section-tight { padding: var(--space-2xl) 0; border-top: 1px solid var(--border); }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; margin-bottom: var(--space-l); gap: var(--space-m); }
.eyebrow { color: var(--accent); font-size: 0.9rem; font-weight: 700; letter-spacing: 0.04em; }
.section-head h2, .page-header h1 { margin: 0 0 var(--space-2xs); font-weight: 800; letter-spacing: -0.01em; }
.section-head h2 { font-size: clamp(1.5rem, 3vw, 2rem); }
.link-arrow { color: var(--accent); font-weight: 600; white-space: nowrap; }
.link-arrow:hover { color: var(--accent-2); }

/* ── Cards ──────────────────────────────────────────────────────────── */
.post-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: var(--space-m); }
.post-card {
  background: var(--bg-elevated); border: 1px solid var(--border);
  border-radius: var(--radius); padding: var(--space-l);
  display: flex; flex-direction: column; gap: var(--space-xs);
  transition: transform 0.25s var(--ease), box-shadow 0.25s ease, border-color 0.25s ease;
}
.post-card:hover { transform: translateY(-4px); box-shadow: var(--card-shadow); border-color: color-mix(in srgb, var(--accent) 35%, var(--border)); }
.post-card h3 { margin: 0; font-size: 1.18rem; line-height: 1.5; }
.post-card h3 a { color: var(--text); }
.post-card h3 a:hover { color: var(--accent); text-decoration: none; }
.post-card p { color: var(--text-muted); margin: 0; font-size: 0.95rem; flex: 1; }
.post-card time, .post-meta { color: var(--text-faint); font-size: 0.85rem; }
.post-tags { display: flex; flex-wrap: wrap; gap: var(--space-2xs); margin-top: var(--space-xs); }
.post-tags span, .tag { background: var(--accent-soft); color: var(--accent); border-radius: 999px; padding: 2px 12px; font-size: 0.8rem; font-weight: 500; }

/* ── Page header / prose ────────────────────────────────────────────── */
.page-header { padding: var(--space-2xl) 0 var(--space-l); }
.page-header h1 { font-size: clamp(1.8rem, 3.5vw, 2.6rem); }
.page-header .post-meta { display: flex; gap: var(--space-m); flex-wrap: wrap; margin-top: var(--space-xs); }

.reading-progress { position: fixed; top: 0; left: 0; height: 3px; width: 0; background: linear-gradient(90deg, var(--accent), var(--accent-2)); z-index: 100; border-radius: 0 3px 3px 0; }

.prose { font-size: 1.05rem; }
.prose h1, .prose h2, .prose h3, .prose h4 { line-height: 1.4; margin: 1.6em 0 0.55em; color: var(--text); }
.prose h2 { font-size: 1.55rem; }
.prose h3 { font-size: 1.25rem; }
.prose p { margin: 0 0 1.1em; }
.prose ul, .prose ol { margin: 0 0 1.1em; padding-inline-start: 1.4em; }
.prose li { margin-bottom: 0.35em; }
.prose code { background: var(--bg-elevated-2); border-radius: 6px; padding: 2px 6px; font-family: var(--font-mono); font-size: 0.9em; }
.prose pre { background: var(--bg-elevated); border: 1px solid var(--border); border-radius: var(--radius); padding: var(--space-m); overflow-x: auto; margin: 0 0 1.1em; }
.prose pre code { background: none; padding: 0; }
.prose blockquote { border-inline-start: 3px solid var(--accent); margin: 0 0 1.1em; padding: var(--space-2xs) var(--space-m); color: var(--text-muted); background: var(--bg-elevated); border-radius: 0 10px 10px 0; }
.prose a { text-decoration: underline; }
.prose hr { border: none; border-top: 1px solid var(--border); margin: var(--space-xl) 0; }

/* ── Footer ─────────────────────────────────────────────────────────── */
.site-footer { border-top: 1px solid var(--border); background: var(--bg-elevated); padding: var(--space-xl) 0 var(--space-m); margin-top: var(--space-2xl); }
.footer-grid { display: flex; justify-content: space-between; gap: var(--space-l); flex-wrap: wrap; }
.footer-note { color: var(--text-muted); max-width: 40ch; margin: 0; }
.footer-social { list-style: none; display: flex; gap: var(--space-s); margin: 0; padding: 0; flex-wrap: wrap; }
.footer-social a {
  color: var(--text-muted); border: 1px solid var(--border);
  border-radius: 999px; padding: 5px 14px; font-size: 0.9rem;
  transition: all 0.2s ease;
}
.footer-social a:hover { color: var(--accent); border-color: var(--accent); text-decoration: none; }
.footer-copy { color: var(--text-faint); font-size: 0.85rem; margin-top: var(--space-l); }

/* ── Reveal on scroll ───────────────────────────────────────────────── */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.7s var(--ease), transform 0.7s var(--ease); }
.reveal.visible { opacity: 1; transform: translateY(0); }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
}

/* ── Pagination ─────────────────────────────────────────────────────── */
.pagination { display: flex; gap: var(--space-2xs); margin: var(--space-xl) 0; justify-content: center; flex-wrap: wrap; }
.pagination a, .pagination span { padding: 6px 14px; border: 1px solid var(--border); border-radius: 10px; color: var(--text-muted); }
.pagination a:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.pagination .active { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; border-color: transparent; }

/* ── Responsive ─────────────────────────────────────────────────────── */
@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; text-align: center; }
  .hero-lede { margin-inline: auto; }
  .hero-cta { justify-content: center; }
  .avatar-wrap { width: 160px; height: 160px; }
  .nav-toggle { display: inline-flex; }
  .nav {
    position: fixed; top: var(--header-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--bg-elevated); border-bottom: 1px solid var(--border);
    padding: var(--space-xs) var(--space-m) var(--space-m);
    transform: translateY(-8px); opacity: 0; pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s var(--ease);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
  }
  .nav.open { opacity: 1; transform: translateY(0); pointer-events: auto; }
  .nav a { padding: 0.85rem 0; border-bottom: 1px solid var(--border); }
  .nav a:last-child { border-bottom: none; }
  .nav a::after { display: none; }
  .header-inner { gap: var(--space-xs); }
}
@media (max-width: 520px) {
  :root { --space-2xl: 3rem; }
  .section-head { flex-direction: column; align-items: flex-start; gap: var(--space-xs); }
  .post-grid { grid-template-columns: 1fr; }
}