/* ===== Vibe Coding with Claude Code — Global Styles ===== */
@import url('https://fonts.googleapis.com/css2?family=DM+Serif+Display:ital@0;1&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --bg: #FAF8F5;
  --bg-alt: #F0EDE8;
  --text: #1a1a1a;
  --text-muted: #5a5a5a;
  --accent: #D4A853;
  --accent-hover: #C49843;
  --sage: #7B9E6B;
  --sage-light: #e8f0e4;
  --terminal-bg: #1e1e2e;
  --terminal-text: #cdd6f4;
  --terminal-green: #a6e3a1;
  --terminal-blue: #89b4fa;
  --terminal-amber: #f9e2af;
  --terminal-red: #f38ba8;
  --terminal-purple: #cba6f7;
  --code-bg: #2d2d3f;
  --badge-starter: #7B9E6B;
  --badge-beginner: #5b8ec9;
  --badge-intermediate: #D4A853;
  --badge-advanced: #d97756;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --radius: 12px;
  --radius-sm: 8px;
  --max-width: 800px;
  --max-width-wide: 1100px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: 'DM Serif Display', Georgia, serif;
  line-height: 1.2;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.2rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.2rem); }
h3 { font-size: clamp(1.2rem, 2.5vw, 1.5rem); }

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

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

/* ===== Navigation ===== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 248, 245, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
  padding: 0.75rem 1.5rem;
}
.site-nav .nav-inner {
  max-width: var(--max-width-wide);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.site-nav .nav-brand {
  font-family: 'DM Serif Display', serif;
  font-size: 1.1rem;
  color: var(--text);
  white-space: nowrap;
}
.site-nav .nav-brand span { color: var(--accent); }
.site-nav .nav-progress {
  flex: 1;
  max-width: 200px;
  height: 6px;
  background: var(--bg-alt);
  border-radius: 3px;
  overflow: hidden;
}
.site-nav .nav-progress-bar {
  height: 100%;
  background: var(--sage);
  border-radius: 3px;
  transition: width 0.5s ease;
}
.site-nav .nav-menu-btn {
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  color: var(--text);
}
.nav-dropdown {
  display: none;
  position: absolute;
  top: 100%;
  right: 0;
  left: 0;
  background: var(--bg);
  border-bottom: 1px solid rgba(0,0,0,0.08);
  box-shadow: var(--shadow-md);
  padding: 1rem 1.5rem;
}
.nav-dropdown.open { display: block; }
.nav-dropdown a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.6rem 0;
  color: var(--text);
  font-size: 0.95rem;
  border-bottom: 1px solid rgba(0,0,0,0.04);
}
.nav-dropdown a:last-child { border-bottom: none; }
.nav-dropdown a:hover { color: var(--accent); }
.nav-dropdown .lesson-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--bg-alt);
  font-size: 0.8rem;
  font-weight: 600;
  flex-shrink: 0;
}
.nav-dropdown a.completed .lesson-num {
  background: var(--sage);
  color: #fff;
}
.nav-dropdown a.active { color: var(--accent); font-weight: 600; }

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 420px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 4rem 1.5rem;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  filter: brightness(0.35);
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
}
.hero h1 {
  color: #fff;
  margin-bottom: 1rem;
  text-shadow: 0 2px 20px rgba(0,0,0,0.3);
}
.hero p {
  color: rgba(255,255,255,0.9);
  font-size: 1.15rem;
  line-height: 1.6;
  text-shadow: 0 1px 8px rgba(0,0,0,0.3);
}

/* ===== Content Container ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2rem 1.5rem;
}
.container-wide {
  max-width: var(--max-width-wide);
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

/* ===== Section ===== */
section { margin-bottom: 3rem; }
section h2 { margin-bottom: 1.25rem; }
section p { margin-bottom: 1rem; }

/* ===== Lesson Card Grid ===== */
.lesson-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}
.lesson-card {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
}
.lesson-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.lesson-card-header {
  padding: 1.5rem 1.5rem 0.75rem;
  display: flex;
  align-items: flex-start;
  gap: 1rem;
}
.lesson-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-alt);
  font-family: 'DM Serif Display', serif;
  font-size: 1.2rem;
  color: var(--text);
  flex-shrink: 0;
}
.lesson-card-header h3 {
  font-size: 1.15rem;
  margin: 0;
}
.lesson-card-body {
  padding: 0 1.5rem 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}
.lesson-card-body p {
  color: var(--text-muted);
  font-size: 0.95rem;
  flex: 1;
}
.lesson-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
  font-size: 0.85rem;
}
.lesson-meta .time {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  color: var(--text-muted);
}
.badge {
  display: inline-block;
  padding: 0.2rem 0.7rem;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #fff;
}
.badge-starter { background: var(--badge-starter); }
.badge-beginner { background: var(--badge-beginner); }
.badge-intermediate { background: var(--badge-intermediate); }
.badge-advanced { background: var(--badge-advanced); }

.lesson-card .cta-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  margin-top: 0.75rem;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--accent);
}

/* ===== Lesson Page Styles ===== */
.lesson-header {
  padding: 2.5rem 1.5rem 2rem;
  background: var(--bg-alt);
  border-bottom: 1px solid rgba(0,0,0,0.06);
}
.lesson-header .container {
  padding: 0;
  max-width: var(--max-width);
  margin: 0 auto;
}
.lesson-header .lesson-label {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}
.lesson-header h1 {
  color: var(--text);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin-bottom: 0.75rem;
}
.lesson-header .objectives {
  list-style: none;
  padding: 0;
}
.lesson-header .objectives li {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 0.25rem 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}
.lesson-header .objectives li svg { flex-shrink: 0; margin-top: 3px; color: var(--sage); }

/* ===== Terminal Mockup ===== */
.terminal {
  background: var(--terminal-bg);
  border-radius: var(--radius);
  overflow: hidden;
  margin: 1.5rem 0;
  box-shadow: var(--shadow-md);
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.88rem;
  line-height: 1.6;
}
.terminal-header {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 0.75rem 1rem;
  background: rgba(0,0,0,0.2);
}
.terminal-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}
.terminal-dot.red { background: #f38ba8; }
.terminal-dot.yellow { background: #f9e2af; }
.terminal-dot.green { background: #a6e3a1; }
.terminal-title {
  margin-left: 0.5rem;
  color: rgba(255,255,255,0.5);
  font-size: 0.8rem;
}
.terminal-body {
  padding: 1rem 1.25rem;
  overflow-x: auto;
}
.terminal-line {
  white-space: pre-wrap;
  word-break: break-word;
}
.terminal-line .prompt {
  color: var(--terminal-green);
}
.terminal-line .command {
  color: var(--terminal-text);
}
.terminal-line .output {
  color: rgba(205, 214, 244, 0.7);
}
.terminal-line .highlight {
  color: var(--terminal-amber);
}
.terminal-line .blue { color: var(--terminal-blue); }
.terminal-line .purple { color: var(--terminal-purple); }
.terminal-line .green { color: var(--terminal-green); }
.terminal-line .red { color: var(--terminal-red); }

/* ===== Code Mockup (Editor) ===== */
.editor-mockup {
  background: var(--code-bg);
  border-radius: var(--radius);
  overflow: hidden;
  margin: 1.5rem 0;
  box-shadow: var(--shadow-md);
}
.editor-tab-bar {
  display: flex;
  gap: 0;
  background: rgba(0,0,0,0.3);
  padding: 0;
}
.editor-tab {
  padding: 0.5rem 1rem;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.78rem;
  color: rgba(255,255,255,0.5);
  border-bottom: 2px solid transparent;
}
.editor-tab.active {
  color: rgba(255,255,255,0.9);
  background: var(--code-bg);
  border-bottom-color: var(--accent);
}
.editor-body {
  padding: 1rem 0;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85rem;
  line-height: 1.7;
  overflow-x: auto;
}
.editor-line {
  display: flex;
  padding: 0 1rem;
}
.editor-line:hover { background: rgba(255,255,255,0.03); }
.editor-line .line-num {
  color: rgba(255,255,255,0.2);
  width: 3ch;
  text-align: right;
  margin-right: 1.5rem;
  flex-shrink: 0;
  user-select: none;
}
.editor-line .line-content {
  color: var(--terminal-text);
  white-space: pre;
}
.editor-line .tag { color: var(--terminal-red); }
.editor-line .attr { color: var(--terminal-amber); }
.editor-line .val { color: var(--terminal-green); }
.editor-line .comment { color: rgba(255,255,255,0.3); font-style: italic; }
.editor-line .keyword { color: var(--terminal-purple); }
.editor-line .string { color: var(--terminal-green); }
.editor-line .func { color: var(--terminal-blue); }

/* ===== Callout Boxes ===== */
.callout {
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-sm);
  margin: 1.5rem 0;
  font-size: 0.95rem;
}
.callout-title {
  font-weight: 700;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.callout-try {
  background: var(--sage-light);
  border-left: 4px solid var(--sage);
}
.callout-try .callout-title { color: var(--sage); }
.callout-tip {
  background: #fdf6e3;
  border-left: 4px solid var(--accent);
}
.callout-tip .callout-title { color: var(--accent-hover); }
.callout-warning {
  background: #fef2f2;
  border-left: 4px solid var(--terminal-red);
}
.callout-warning .callout-title { color: #b91c1c; }

/* ===== Quiz / Interactive ===== */
.quiz {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
  margin: 2rem 0;
}
.quiz h3 { font-size: 1.1rem; margin-bottom: 1rem; }
.quiz-question { margin-bottom: 1.5rem; }
.quiz-question p { font-weight: 500; margin-bottom: 0.75rem; }
.quiz-options { display: flex; flex-direction: column; gap: 0.5rem; }
.quiz-option {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border: 2px solid var(--bg-alt);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s;
  font-size: 0.95rem;
}
.quiz-option:hover { border-color: var(--accent); background: #fffdf5; }
.quiz-option.selected { border-color: var(--accent); background: #fffdf5; }
.quiz-option.correct { border-color: var(--sage); background: var(--sage-light); }
.quiz-option.incorrect { border-color: var(--terminal-red); background: #fef2f2; }
.quiz-option .option-marker {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  border: 2px solid var(--bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 0.75rem;
  font-weight: 700;
}
.quiz-option.selected .option-marker { border-color: var(--accent); background: var(--accent); color: #fff; }
.quiz-option.correct .option-marker { border-color: var(--sage); background: var(--sage); color: #fff; }
.quiz-option.incorrect .option-marker { border-color: var(--terminal-red); background: var(--terminal-red); color: #fff; }
.quiz-feedback {
  margin-top: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  display: none;
}
.quiz-feedback.show { display: block; }
.quiz-feedback.correct { background: var(--sage-light); color: #2d5a1e; }
.quiz-feedback.incorrect { background: #fef2f2; color: #991b1b; }
.quiz-btn {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 0.6rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background 0.2s;
  margin-top: 1rem;
}
.quiz-btn:hover { background: var(--accent-hover); }

/* ===== Flashcards ===== */
.flashcard-deck {
  perspective: 1000px;
  margin: 2rem 0;
}
.flashcard-counter {
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.flashcard {
  width: 100%;
  max-width: 500px;
  margin: 0 auto;
  height: 280px;
  cursor: pointer;
  position: relative;
}
.flashcard-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}
.flashcard.flipped .flashcard-inner { transform: rotateY(180deg); }
.flashcard-front, .flashcard-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  text-align: center;
}
.flashcard-front {
  background: #fff;
  box-shadow: var(--shadow-md);
}
.flashcard-front h4 { font-size: 1.3rem; margin-bottom: 0.5rem; }
.flashcard-front p { color: var(--text-muted); font-size: 0.9rem; }
.flashcard-back {
  background: var(--terminal-bg);
  color: var(--terminal-text);
  transform: rotateY(180deg);
  box-shadow: var(--shadow-md);
}
.flashcard-back h4 { font-size: 1.2rem; color: var(--terminal-green); margin-bottom: 0.5rem; }
.flashcard-back p { color: rgba(205, 214, 244, 0.8); font-size: 0.9rem; }
.flashcard-nav {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1rem;
}
.flashcard-nav button {
  background: var(--bg-alt);
  border: none;
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.9rem;
  font-weight: 500;
  transition: background 0.2s;
}
.flashcard-nav button:hover { background: #e0dcd7; }

/* ===== Fill in the Blank ===== */
.fill-blank {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
  margin: 2rem 0;
}
.fill-blank h3 { font-size: 1.1rem; margin-bottom: 1rem; }
.fill-blank-item {
  margin-bottom: 1.25rem;
  padding-bottom: 1.25rem;
  border-bottom: 1px solid var(--bg-alt);
}
.fill-blank-item:last-child { border-bottom: none; margin-bottom: 0; padding-bottom: 0; }
.fill-blank-sentence {
  font-size: 1rem;
  line-height: 1.8;
  margin-bottom: 0.5rem;
}
.fill-blank-input {
  display: inline-block;
  border: none;
  border-bottom: 2px solid var(--accent);
  background: transparent;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.9rem;
  padding: 0.2rem 0.5rem;
  min-width: 120px;
  outline: none;
  transition: border-color 0.2s;
}
.fill-blank-input:focus { border-bottom-color: var(--sage); }
.fill-blank-input.correct { border-bottom-color: var(--sage); color: #2d5a1e; }
.fill-blank-input.incorrect { border-bottom-color: var(--terminal-red); color: #991b1b; }

/* ===== Lesson Navigation ===== */
.lesson-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 2rem 0;
  margin-top: 3rem;
  border-top: 1px solid var(--bg-alt);
}
.lesson-nav a {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 1.25rem;
  background: #fff;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  font-weight: 500;
  font-size: 0.9rem;
  color: var(--text);
  transition: box-shadow 0.2s, transform 0.2s;
}
.lesson-nav a:hover { box-shadow: var(--shadow-md); transform: translateY(-1px); }
.lesson-nav .home-link { color: var(--text-muted); }

/* ===== Footer ===== */
.site-footer {
  text-align: center;
  padding: 2rem 1.5rem;
  color: var(--text-muted);
  font-size: 0.85rem;
  border-top: 1px solid rgba(0,0,0,0.06);
  margin-top: 2rem;
}

/* ===== Comparison (Before/After) ===== */
.comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin: 1.5rem 0;
}
.comparison-panel {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.comparison-label {
  padding: 0.6rem 1rem;
  font-weight: 700;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-align: center;
}
.comparison-panel.bad .comparison-label { background: #fef2f2; color: #991b1b; }
.comparison-panel.good .comparison-label { background: var(--sage-light); color: #2d5a1e; }
.comparison-panel .terminal { margin: 0; border-radius: 0; box-shadow: none; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  body { font-size: 16px; }
  .lesson-grid { grid-template-columns: 1fr; }
  .comparison { grid-template-columns: 1fr; }
  .hero { min-height: 340px; padding: 3rem 1.5rem; }
  .container, .container-wide { padding: 1.5rem 1rem; }
}

/* ===== Utility ===== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  border: 0;
}
.text-muted { color: var(--text-muted); }
.text-accent { color: var(--accent); }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }