@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

/* ==========================================================================
   Light Theme (Default / Root)
   ========================================================================== */
:root {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f1f5f9;
  --border-color: #e2e8f0;
  --border-glow: rgba(6, 182, 212, 0.3);
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --accent-cyan: #0891b2;
  --accent-blue: #2563eb;
  --accent-indigo: #4f46e5;
  --accent-purple: #9333ea;
  --accent-emerald: #059669;
  --gradient-primary: linear-gradient(135deg, #06b6d4 0%, #6366f1 50%, #8b5cf6 100%);
  --gradient-card: linear-gradient(180deg, rgba(255, 255, 255, 0.9) 0%, rgba(248, 250, 252, 0.9) 100%);
  --shadow-glow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

/* ==========================================================================
   Dark Theme (html.dark)
   ========================================================================== */
html.dark {
  --bg-primary: #090d16;
  --bg-secondary: #0f172a;
  --bg-card: rgba(15, 23, 42, 0.75);
  --bg-card-hover: rgba(30, 41, 59, 0.85);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(56, 189, 248, 0.3);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent-cyan: #38bdf8;
  --accent-blue: #3b82f6;
  --accent-indigo: #6366f1;
  --accent-purple: #a855f7;
  --accent-emerald: #10b981;
  --gradient-primary: linear-gradient(135deg, #38bdf8 0%, #6366f1 50%, #a855f7 100%);
  --gradient-card: linear-gradient(180deg, rgba(255, 255, 255, 0.03) 0%, rgba(255, 255, 255, 0) 100%);
  --shadow-glow: 0 0 25px rgba(56, 189, 248, 0.15);
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.2s ease, color 0.2s ease;
}

/* Background Atmosphere */
html.dark body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100vw;
  height: 600px;
  background: radial-gradient(circle at 50% 0%, rgba(56, 189, 248, 0.12) 0%, rgba(99, 102, 241, 0.05) 50%, transparent 80%);
  pointer-events: none;
  z-index: 0;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
  width: 100%;
  position: relative;
  z-index: 1;
}

/* Form Controls */
.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 0.95rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.form-control:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.15);
}

/* Code Typography */
pre, code {
  font-family: var(--font-mono);
}

/* Article Markdown Typography */
.article-content {
  color: var(--text-primary);
}

.article-content h2 {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-top: 2.5rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
  letter-spacing: -0.025em;
}

.article-content h3 {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.article-content p {
  margin-bottom: 1.35rem;
  line-height: 1.8;
  color: var(--text-secondary);
}

.article-content ul, .article-content ol {
  margin: 1rem 0 1.5rem 1.5rem;
  color: var(--text-secondary);
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-content code {
  background: rgba(148, 163, 184, 0.15);
  border: 1px solid rgba(148, 163, 184, 0.25);
  padding: 0.2rem 0.45rem;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--accent-cyan);
}

html.dark .article-content code {
  background: rgba(30, 41, 59, 0.8);
  border-color: rgba(56, 189, 248, 0.2);
  color: #38bdf8;
}

.article-content pre {
  background: #0f172a;
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.25rem;
  overflow-x: auto;
  margin: 1.75rem 0;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
  color: #93c5fd;
}

html.dark .article-content pre {
  background: #060911;
  border-color: #1e293b;
}

.article-content blockquote {
  border-left: 4px solid var(--accent-cyan);
  background: rgba(6, 182, 212, 0.05);
  padding: 1rem 1.25rem;
  border-radius: 0 12px 12px 0;
  margin: 1.5rem 0;
  font-style: italic;
  color: var(--text-secondary);
}