/* === PLAYWRIGHT PYTHON LEARNING HUB === */
/* Terminal-editorial hybrid aesthetic */

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

:root {
  --bg-primary: #0a0e17;
  --bg-secondary: #0f1520;
  --bg-card: #131a28;
  --bg-card-hover: #182035;
  --bg-code: #0d1117;
  --text-primary: #e2e8f0;
  --text-secondary: #8899b0;
  --text-muted: #4a5a72;
  --accent-green: #2dd4a8;
  --accent-green-dim: rgba(45,212,168,0.15);
  --accent-cyan: #22d3ee;
  --accent-orange: #fb923c;
  --accent-purple: #a78bfa;
  --accent-red: #f87171;
  --accent-yellow: #fbbf24;
  --border-color: #1e293b;
  --border-glow: rgba(45,212,168,0.3);
  --font-display: 'Outfit', 'Noto Sans SC', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  --font-body: 'Outfit', 'Noto Sans SC', sans-serif;
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* === NOISE OVERLAY === */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)' opacity='0.03'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 9999;
}

/* === GRID BACKGROUND === */
.grid-bg {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(45,212,168,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(45,212,168,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: 0;
}

/* === NAVIGATION === */
nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 0 2rem;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(10,14,23,0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.nav-logo .pw-icon {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  color: var(--bg-primary);
  font-weight: 700;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 0.45rem 1rem;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  position: relative;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--accent-green);
  background: var(--accent-green-dim);
}

.nav-hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
}

/* === LAYOUT === */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  position: relative;
  z-index: 1;
}

.page-content {
  padding-top: 100px;
  padding-bottom: 80px;
  min-height: 100vh;
}

section { margin-bottom: 5rem; }

/* === TYPOGRAPHY === */
h1, h2, h3, h4 { font-family: var(--font-display); line-height: 1.2; }

h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 900;
  letter-spacing: -0.03em;
}

h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 1.5rem;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

p { color: var(--text-secondary); margin-bottom: 1rem; }
p.lead { font-size: 1.15rem; line-height: 1.8; }

.gradient-text {
  background: linear-gradient(135deg, var(--accent-green), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.tag {
  display: inline-block;
  padding: 0.2rem 0.65rem;
  font-size: 0.72rem;
  font-family: var(--font-mono);
  font-weight: 500;
  border-radius: 999px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.tag-green { background: var(--accent-green-dim); color: var(--accent-green); }
.tag-cyan { background: rgba(34,211,238,0.12); color: var(--accent-cyan); }
.tag-orange { background: rgba(251,146,60,0.12); color: var(--accent-orange); }
.tag-purple { background: rgba(167,139,250,0.12); color: var(--accent-purple); }
.tag-red { background: rgba(248,113,113,0.12); color: var(--accent-red); }

/* === CODE BLOCKS === */
.code-block {
  background: var(--bg-code);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
  margin: 1.25rem 0;
  font-size: 0.85rem;
}

.code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.6rem 1rem;
  background: rgba(30,41,59,0.5);
  border-bottom: 1px solid var(--border-color);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.code-dots {
  display: flex;
  gap: 6px;
}

.code-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.code-dots span:nth-child(1) { background: var(--accent-red); opacity: 0.7; }
.code-dots span:nth-child(2) { background: var(--accent-yellow); opacity: 0.7; }
.code-dots span:nth-child(3) { background: var(--accent-green); opacity: 0.7; }

.code-block pre {
  padding: 1.25rem;
  overflow-x: auto;
  font-family: var(--font-mono);
  line-height: 1.65;
  color: var(--text-primary);
}

.code-block .kw { color: var(--accent-purple); }
.code-block .fn { color: var(--accent-cyan); }
.code-block .str { color: var(--accent-green); }
.code-block .cm { color: var(--text-muted); font-style: italic; }
.code-block .op { color: var(--accent-orange); }
.code-block .num { color: var(--accent-orange); }
.code-block .cls { color: var(--accent-yellow); }
.code-block .param { color: var(--accent-red); font-style: italic; }

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: rgba(45,212,168,0.08);
  color: var(--accent-green);
  padding: 0.15em 0.45em;
  border-radius: 4px;
}

/* === CARDS === */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--accent-green), var(--accent-cyan));
  opacity: 0;
  transition: var(--transition);
}

.card:hover {
  border-color: var(--border-glow);
  background: var(--bg-card-hover);
  transform: translateY(-2px);
}

.card:hover::before { opacity: 1; }

.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin-bottom: 1rem;
}

.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 1.25rem; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 1.25rem; }
.grid-4 { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.25rem; }

/* === HERO === */
.hero {
  padding: 6rem 0 4rem;
  text-align: center;
  position: relative;
}

.hero-glow {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.12;
  pointer-events: none;
}

.hero-glow-1 {
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-green);
}

.hero-glow-2 {
  top: -100px;
  right: -100px;
  background: var(--accent-cyan);
  width: 400px;
  height: 400px;
  opacity: 0.08;
}

.hero h1 { margin-bottom: 1.25rem; }

.hero .subtitle {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 2.5rem;
  line-height: 1.8;
}

/* === BUTTONS === */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0.7rem 1.5rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 0.92rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: var(--transition);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-green), #1eb896);
  color: var(--bg-primary);
}

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 30px rgba(45,212,168,0.3);
}

.btn-ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

.btn-ghost:hover {
  border-color: var(--accent-green);
  color: var(--accent-green);
}

.btn-group { display: flex; gap: 0.75rem; justify-content: center; flex-wrap: wrap; }

/* === TABLE === */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  margin: 1.5rem 0;
}

.comparison-table thead th {
  padding: 1rem 1.25rem;
  text-align: left;
  font-weight: 600;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  border-bottom: 2px solid var(--border-color);
  white-space: nowrap;
}

.comparison-table thead th:first-child { color: var(--text-primary); }

.comparison-table tbody td {
  padding: 0.9rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-secondary);
}

.comparison-table tbody tr:hover td {
  background: rgba(45,212,168,0.03);
}

.comparison-table .check { color: var(--accent-green); font-weight: 700; }
.comparison-table .cross { color: var(--accent-red); opacity: 0.5; }
.comparison-table .partial { color: var(--accent-yellow); }
.comparison-table .highlight-col { background: rgba(45,212,168,0.04); }

/* === SECTION HEADER === */
.section-header {
  margin-bottom: 2.5rem;
}

.section-header .overline {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--accent-green);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.5rem;
  display: block;
}

/* === STEP LIST === */
.steps {
  counter-reset: step;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.step {
  counter-increment: step;
  display: flex;
  gap: 1.25rem;
  align-items: flex-start;
}

.step-num {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  background: var(--accent-green-dim);
  color: var(--accent-green);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.9rem;
}

.step-content h3 { margin-bottom: 0.35rem; }
.step-content p { margin-bottom: 0; }

/* === TABS === */
.tabs {
  display: flex;
  gap: 0.25rem;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 2rem;
  overflow-x: auto;
}

.tab-btn {
  padding: 0.65rem 1.25rem;
  background: none;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  position: relative;
  white-space: nowrap;
  transition: var(--transition);
}

.tab-btn:hover { color: var(--text-secondary); }

.tab-btn.active {
  color: var(--accent-green);
}

.tab-btn.active::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-green);
}

.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* === FOOTER === */
footer {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border-color);
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
  position: relative;
  z-index: 1;
}

footer a {
  color: var(--accent-green);
  text-decoration: none;
}

/* === ARCHITECTURE DIAGRAM === */
.arch-diagram {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 2.5rem;
  margin: 2rem 0;
  position: relative;
  overflow: hidden;
}

.arch-layer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.arch-box {
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  text-align: center;
  border: 1px solid;
  min-width: 140px;
}

.arch-arrow {
  text-align: center;
  color: var(--text-muted);
  font-size: 1.5rem;
  margin: 0.5rem 0;
  letter-spacing: 0.3em;
}

.arch-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  text-align: center;
}

/* === TIMELINE === */
.timeline {
  position: relative;
  padding-left: 2rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent-green), var(--accent-cyan), transparent);
}

.timeline-item {
  position: relative;
  padding-bottom: 2rem;
  padding-left: 1.5rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2rem;
  top: 6px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent-green);
  border: 2px solid var(--bg-primary);
  transform: translateX(-50%);
  margin-left: 1px;
}

/* === ANIMATIONS === */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.animate-in {
  opacity: 0;
  animation: fadeInUp 0.6s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }
.delay-5 { animation-delay: 0.5s; }
.delay-6 { animation-delay: 0.6s; }

/* === SCROLL REVEAL === */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* === LANGUAGE SWITCHER === */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 2px;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 3px;
  margin-left: 0.75rem;
}

.lang-switcher a {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 0.3rem 0.75rem;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--text-muted);
  text-decoration: none;
  border-radius: 6px;
  transition: var(--transition);
  white-space: nowrap;
}

.lang-switcher a:hover { color: var(--text-secondary); }

.lang-switcher a.lang-active {
  color: var(--bg-primary);
  background: var(--accent-green);
}

.lang-switcher .lang-ts.lang-active {
  background: #3178c6;
  color: #fff;
}

.lang-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  display: inline-block;
}

.lang-dot-py { background: #3776ab; }
.lang-dot-ts { background: #3178c6; }

/* === RESPONSIVE === */
@media (max-width: 768px) {
  .container { padding: 0 1.25rem; }
  nav { padding: 0 1.25rem; }
  .nav-links { display: none; }
  .nav-hamburger { display: block; }
  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(10,14,23,0.97);
    backdrop-filter: blur(20px);
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
  }
  .hero { padding: 3rem 0 2rem; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .comparison-table { font-size: 0.8rem; }
  .comparison-table thead th,
  .comparison-table tbody td { padding: 0.65rem 0.75rem; }
  .arch-diagram { padding: 1.5rem; }
}