/* AI Daily — refined tech blog */

/* ============ TOKENS ============ */
:root {
  --bg: #0a0a0f;
  --bg-soft: #12121a;
  --bg-card: #1a1a24;
  --bg-elevated: #20202c;
  --border: #2a2a38;
  --border-soft: #1f1f2c;
  --text: #e8e8ed;
  --text-dim: #9a9aab;
  --text-faint: #6a6a7a;
  --accent: #7c5cff;
  --accent-2: #00d4ff;
  --accent-glow: rgba(124, 92, 255, 0.4);
  --accent-glow-2: rgba(0, 212, 255, 0.3);
  --tag-bg: #252535;
  --tag-text: #b8b8c8;
  --success: #4ade80;
  --warning: #fbbf24;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
  --shadow-md: 0 8px 24px rgba(0,0,0,0.4);
  --shadow-glow: 0 0 0 1px var(--accent), 0 8px 32px rgba(124,92,255,0.2);
  --radius: 14px;
  --radius-sm: 8px;
  --radius-lg: 20px;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", ui-monospace, "SF Mono", Menlo, monospace;
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

/* ============ RESET ============ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; } }

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* Subtle animated background gradient */
body::before {
  content: "";
  position: fixed; inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 20% 0%, rgba(124,92,255,0.08), transparent 50%),
    radial-gradient(ellipse 60% 40% at 80% 10%, rgba(0,212,255,0.05), transparent 50%),
    radial-gradient(ellipse 100% 60% at 50% 100%, rgba(124,92,255,0.04), transparent 50%);
  pointer-events: none; z-index: 0;
  animation: bg-shift 20s ease-in-out infinite alternate;
}
body::after {
  content: "";
  position: fixed; inset: 0;
  background-image: radial-gradient(circle at 1px 1px, rgba(255,255,255,0.015) 1px, transparent 0);
  background-size: 32px 32px;
  pointer-events: none; z-index: 0;
  mask-image: radial-gradient(ellipse 100% 80% at 50% 0%, black 30%, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 100% 80% at 50% 0%, black 30%, transparent 80%);
}
@keyframes bg-shift {
  0% { transform: translate(0, 0); }
  100% { transform: translate(20px, -20px); }
}

::selection { background: var(--accent); color: white; }
::-moz-selection { background: var(--accent); color: white; }

/* Custom scrollbar */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg-soft); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 5px; border: 2px solid var(--bg-soft); }
::-webkit-scrollbar-thumb:hover { background: var(--accent); }
* { scrollbar-width: thin; scrollbar-color: var(--border) var(--bg-soft); }

/* Focus rings */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

.container { max-width: 760px; margin: 0 auto; padding: 0 24px; position: relative; z-index: 1; }

/* ============ HEADER ============ */
.site-header {
  border-bottom: 1px solid var(--border-soft);
  padding: 20px 0;
  margin-bottom: 48px;
  position: sticky; top: 0; z-index: 50;
  background: rgba(10, 10, 15, 0.75);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  transition: padding 0.3s var(--ease), background 0.3s var(--ease);
}
.site-header.scrolled { padding: 14px 0; background: rgba(10, 10, 15, 0.92); border-bottom-color: var(--border); }
.site-header .container { display: flex; align-items: center; justify-content: space-between; }

.logo {
  font-size: 1.2rem; font-weight: 700; letter-spacing: -0.02em;
  text-decoration: none; color: var(--text);
  display: flex; align-items: center; gap: 10px;
  transition: opacity 0.2s var(--ease);
}
.logo:hover { opacity: 0.85; }
.logo .dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0 var(--accent-glow);
  animation: pulse 2.4s ease-in-out infinite;
  position: relative;
}
.logo .dot::after {
  content: ""; position: absolute; inset: -4px;
  border-radius: 50%; border: 1px solid var(--accent);
  opacity: 0; animation: ping 2.4s ease-out infinite;
}
@keyframes pulse { 0%, 100% { transform: scale(1); } 50% { transform: scale(1.15); } }
@keyframes ping { 0% { transform: scale(1); opacity: 0.8; } 100% { transform: scale(2.5); opacity: 0; } }

.nav-links { display: flex; gap: 8px; }
.nav-links a {
  color: var(--text-dim); text-decoration: none; font-size: 0.88rem; font-weight: 500;
  padding: 8px 14px; border-radius: var(--radius-sm);
  transition: all 0.2s var(--ease);
}
.nav-links a:hover { color: var(--text); background: var(--bg-card); }

/* ============ HERO / INDEX HEAD ============ */
.hero { padding: 32px 0 40px; position: relative; }
.hero h1 {
  font-size: clamp(2rem, 5vw, 2.8rem); font-weight: 800; letter-spacing: -0.035em;
  background: linear-gradient(135deg, var(--text) 0%, var(--accent) 50%, var(--accent-2) 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text; margin-bottom: 12px; line-height: 1.1;
  background-size: 200% 200%;
  animation: gradient-flow 8s ease infinite;
}
@keyframes gradient-flow { 0%, 100% { background-position: 0% 50%; } 50% { background-position: 100% 50%; } }
.hero p { color: var(--text-dim); font-size: 1.05rem; max-width: 600px; }
.hero .meta {
  color: var(--text-faint); font-size: 0.85rem; margin-top: 20px;
  display: inline-flex; align-items: center; gap: 8px; flex-wrap: wrap;
}
.hero .meta .pill {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--bg-card); border: 1px solid var(--border);
  padding: 6px 12px; border-radius: 99px; font-size: 0.78rem;
}
.hero .meta .pill::before {
  content: ""; width: 6px; height: 6px; border-radius: 50%;
  background: var(--success); box-shadow: 0 0 8px var(--success);
  animation: pulse 2s ease-in-out infinite;
}

/* ============ POST LIST ============ */
.posts { display: flex; flex-direction: column; gap: 14px; padding-bottom: 80px; }

.post-card {
  display: block; padding: 24px 26px;
  background: var(--bg-card);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius);
  text-decoration: none; color: inherit;
  transition: all 0.3s var(--ease-out);
  position: relative;
  overflow: hidden;
}
.post-card::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 2px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transform: scaleX(0); transform-origin: left;
  transition: transform 0.4s var(--ease-out);
}
.post-card:hover {
  border-color: var(--accent);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}
.post-card:hover::before { transform: scaleX(1); }

.post-card .date {
  font-size: 0.75rem; color: var(--text-faint); text-transform: uppercase;
  letter-spacing: 0.08em; margin-bottom: 10px;
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
}
.post-card .date .badge {
  background: var(--tag-bg); color: var(--accent);
  padding: 3px 10px; border-radius: 6px; font-weight: 600;
  font-size: 0.68rem; letter-spacing: 0.04em;
  text-transform: none;
}
.post-card .date .new-badge {
  background: linear-gradient(135deg, var(--success), #22c55e);
  color: #052e0f; font-weight: 700;
  padding: 3px 10px; border-radius: 6px;
  font-size: 0.68rem; letter-spacing: 0.04em;
  text-transform: none;
  box-shadow: 0 2px 8px rgba(74, 222, 128, 0.3);
}
.post-card h2 {
  font-size: 1.35rem; font-weight: 700; letter-spacing: -0.018em;
  margin-bottom: 8px; color: var(--text);
  transition: color 0.2s var(--ease);
}
.post-card:hover h2 { color: var(--accent); }
.post-card p { color: var(--text-dim); font-size: 0.95rem; line-height: 1.6; }
.post-card .read-more {
  display: inline-flex; align-items: center; gap: 6px;
  color: var(--accent); font-size: 0.85rem; font-weight: 600; margin-top: 14px;
  transition: gap 0.2s var(--ease);
}
.post-card:hover .read-more { gap: 10px; }
.post-card .read-more::after { content: "→"; transition: transform 0.2s var(--ease); }
.post-card:hover .read-more::after { transform: translateX(2px); }

/* ============ SINGLE POST ============ */
.post { padding: 24px 0 80px; }

/* Reading progress bar */
.reading-progress {
  position: fixed; top: 0; left: 0; right: 0; height: 3px;
  background: var(--accent);
  transform-origin: left;
  transform: scaleX(0);
  z-index: 100;
  transition: transform 0.1s linear;
  box-shadow: 0 0 8px var(--accent-glow);
}

.hero-image {
  margin: 0 0 36px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  position: relative;
  aspect-ratio: 16/9;
  max-height: 480px;
}
.hero-image img {
  display: block;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: 0;
  animation: fade-in 0.6s var(--ease-out) 0.2s forwards;
}
@keyframes fade-in { to { opacity: 1; } }
.hero-image .credit {
  position: absolute; bottom: 10px; right: 12px;
  background: rgba(0, 0, 0, 0.7);
  color: var(--text-dim);
  padding: 5px 11px;
  border-radius: 99px;
  font-size: 0.72rem;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,0.1);
}

.post-header { margin-bottom: 36px; padding-bottom: 24px; border-bottom: 1px solid var(--border-soft); }
.post-header .meta-row {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  color: var(--text-faint); font-size: 0.82rem; margin-bottom: 14px;
}
.post-header .meta-row .dot-sep { width: 3px; height: 3px; background: var(--text-faint); border-radius: 50%; }
.post-header h1 {
  font-size: clamp(1.8rem, 4.5vw, 2.4rem); font-weight: 800; letter-spacing: -0.028em;
  line-height: 1.2; margin-bottom: 16px;
}
.post-header .summary { color: var(--text-dim); font-size: 1.1rem; line-height: 1.6; font-weight: 400; }
.post-header .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 20px; }
.tag {
  background: var(--tag-bg); color: var(--tag-text);
  padding: 5px 12px; border-radius: 99px; font-size: 0.78rem; font-weight: 500;
  transition: all 0.2s var(--ease);
  border: 1px solid transparent;
}
.tag:hover { background: var(--bg-elevated); color: var(--text); border-color: var(--border); }

.post-body { font-size: 1.05rem; line-height: 1.85; color: var(--text); }
.post-body > * + * { margin-top: 1em; }
.post-body h2 {
  font-size: 1.5rem; font-weight: 700; letter-spacing: -0.02em;
  margin-top: 2.5em !important; margin-bottom: 0.8em !important;
  color: var(--text); padding-top: 4px;
  scroll-margin-top: 100px;
}
.post-body h3 {
  font-size: 1.2rem; font-weight: 700;
  margin-top: 2em !important; margin-bottom: 0.6em !important;
  color: var(--text);
  scroll-margin-top: 100px;
}
.post-body p { color: var(--text); }
.post-body p:first-of-type::first-letter {
  float: left; font-size: 3.4em; line-height: 0.85; font-weight: 800;
  margin: 0.08em 0.1em 0 0; color: var(--accent);
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.post-body a { color: var(--accent); text-decoration: none; border-bottom: 1px solid transparent; transition: border-color 0.2s var(--ease); }
.post-body a:hover { border-bottom-color: var(--accent); }
.post-body strong { color: var(--text); font-weight: 700; }
.post-body em { color: var(--text-dim); }
.post-body ul, .post-body ol { margin: 1.2em 0 1.2em 1.5em; }
.post-body li { margin-bottom: 0.5em; }
.post-body li::marker { color: var(--accent); }
.post-body code {
  background: var(--bg-soft); padding: 2px 7px; border-radius: 5px;
  font-family: var(--font-mono); font-size: 0.88em;
  color: var(--accent-2);
  border: 1px solid var(--border-soft);
}
.post-body pre {
  background: var(--bg-soft); border: 1px solid var(--border);
  padding: 18px 22px; border-radius: var(--radius-sm); overflow-x: auto;
  font-size: 0.9rem; line-height: 1.6;
}
.post-body pre code { background: none; padding: 0; color: var(--text); border: none; }
.post-body blockquote {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 20px; margin: 1.5em 0;
  color: var(--text-dim); font-style: italic;
  background: linear-gradient(90deg, rgba(124,92,255,0.05), transparent 30%);
  border-radius: 0 8px 8px 0;
}
.post-body img { max-width: 100%; border-radius: var(--radius-sm); border: 1px solid var(--border); }
.post-body hr { border: none; height: 1px; background: var(--border); margin: 2.5em 0; }
.post-body table { width: 100%; border-collapse: collapse; margin: 1.5em 0; font-size: 0.95rem; }
.post-body th, .post-body td { padding: 10px 14px; text-align: left; border-bottom: 1px solid var(--border-soft); }
.post-body th { background: var(--bg-soft); font-weight: 600; color: var(--text); }
.post-body tr:hover td { background: var(--bg-soft); }

.post-footer {
  margin-top: 56px; padding-top: 28px; border-top: 1px solid var(--border-soft);
  display: flex; justify-content: space-between; align-items: center; gap: 16px; flex-wrap: wrap;
  color: var(--text-faint); font-size: 0.85rem;
}
.post-footer .actions { display: flex; gap: 8px; }
.post-footer .action-btn {
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--bg-card); border: 1px solid var(--border-soft);
  color: var(--text-dim); padding: 8px 14px; border-radius: var(--radius-sm);
  font-size: 0.82rem; font-weight: 500; cursor: pointer;
  text-decoration: none; font-family: inherit;
  transition: all 0.2s var(--ease);
}
.post-footer .action-btn:hover { color: var(--text); border-color: var(--accent); background: var(--bg-elevated); }
.post-footer .action-btn.copied { color: var(--success); border-color: var(--success); }

/* Back to top */
.back-to-top {
  position: fixed; bottom: 24px; right: 24px;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--bg-card); border: 1px solid var(--border);
  color: var(--text-dim); cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  opacity: 0; transform: translateY(10px); pointer-events: none;
  transition: all 0.3s var(--ease);
  z-index: 40;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
}
.back-to-top.visible { opacity: 1; transform: translateY(0); pointer-events: auto; }
.back-to-top:hover { color: var(--accent); border-color: var(--accent); transform: translateY(-2px); }

/* ============ FOOTER ============ */
.site-footer {
  border-top: 1px solid var(--border-soft);
  padding: 32px 0; margin-top: 48px;
  color: var(--text-faint); font-size: 0.85rem; text-align: center;
  position: relative; z-index: 1;
}
.site-footer a { color: var(--text-dim); text-decoration: none; transition: color 0.2s var(--ease); }
.site-footer a:hover { color: var(--accent); }
.site-footer .heart { color: var(--accent); }

/* ============ RESPONSIVE ============ */
@media (max-width: 600px) {
  .container { padding: 0 18px; }
  .hero { padding: 20px 0 28px; }
  .hero h1 { font-size: 1.85rem; }
  .post-card { padding: 20px; }
  .post-card h2 { font-size: 1.15rem; }
  .post-header h1 { font-size: 1.7rem; }
  .post-body { font-size: 1rem; }
  .post-body p:first-of-type::first-letter { font-size: 2.8em; }
  .nav-links a { padding: 6px 10px; font-size: 0.82rem; }
  .post-footer { flex-direction: column; align-items: flex-start; }
  .back-to-top { bottom: 16px; right: 16px; width: 40px; height: 40px; }
}

/* ============ PRINT ============ */
@media print {
  body::before, body::after { display: none; }
  .site-header, .site-footer, .reading-progress, .back-to-top, .post-footer .actions { display: none; }
  .post-body { font-size: 12pt; color: black; }
  .post-body a { color: black; text-decoration: underline; }
  .post-card { break-inside: avoid; }
}