/* ============================================================
   AceMyExam — Linear/Vercel-Inspired Design System
   Light & dark mode with gradient accents
   ============================================================ */

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

/* ---- Theme Variables ---- */
:root {
  /* LLM brand colors */
  --gemini-color: #4285f4;
  --chatgpt-color: #10a37f;
  --claude-color: #a97cf8;

  /* Shared */
  --radius: 10px;
  --radius-lg: 16px;
  --transition: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', 'Fira Code', 'Consolas', monospace;
}

/* ---- Dark Theme ---- */
[data-theme="dark"] {
  --bg-base: #000000;
  --bg-surface: #0B0B0C;
  --bg-elevated: #0B0B0C;
  --bg-hover: #151518;
  --bg-active: #1a1a1f;

  --border-subtle: #1F1F23;
  --border-default: #1F1F23;
  --border-strong: #2a2a30;
  --border-accent: rgba(168, 85, 247, 0.4);

  --text-primary: #FFFFFF;
  --text-secondary: #A1A1AA;
  --text-muted: #71717A;
  --text-on-accent: #ffffff;

  --accent: #a855f7;
  --accent-blue: #3b82f6;
  --accent-muted: rgba(168, 85, 247, 0.12);
  --accent-glow: rgba(168, 85, 247, 0.08);

  --success: #4ade80;
  --success-bg: rgba(74, 222, 128, 0.12);
  --warning: #fbbf24;
  --warning-bg: rgba(251, 191, 36, 0.12);
  --warning-border: rgba(251, 191, 36, 0.25);

  --prompt-bg: #0a0a0c;
  --prompt-border: #1F1F23;
  --prompt-text: #e0e0e4;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 60px rgba(168, 85, 247, 0.06);

  --gradient-accent: linear-gradient(135deg, #c084fc 0%, #3b82f6 100%);
  --gradient-accent-hover: linear-gradient(135deg, #d8b4fe 0%, #60a5fa 100%);
  --gradient-hero: linear-gradient(135deg, #c084fc 0%, #3b82f6 100%);
  --gradient-glow: radial-gradient(ellipse at center, rgba(168,85,247,0.15) 0%, rgba(59,130,246,0.1) 40%, transparent 70%);

  color-scheme: dark;
}

/* ---- Light Theme ---- */
[data-theme="light"] {
  --bg-base: #FFFFFF;
  --bg-surface: #F9F9FB;
  --bg-elevated: #F9F9FB;
  --bg-hover: #f0f0f3;
  --bg-active: #e8e8ec;

  --border-subtle: #E4E4E7;
  --border-default: #E4E4E7;
  --border-strong: #d4d4d8;
  --border-accent: rgba(168, 85, 247, 0.3);

  --text-primary: #111111;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --text-on-accent: #ffffff;

  --accent: #a855f7;
  --accent-blue: #3b82f6;
  --accent-muted: rgba(168, 85, 247, 0.08);
  --accent-glow: rgba(168, 85, 247, 0.05);

  --success: #059669;
  --success-bg: rgba(5, 150, 105, 0.08);
  --warning: #b45309;
  --warning-bg: rgba(180, 83, 9, 0.06);
  --warning-border: rgba(180, 83, 9, 0.15);

  --prompt-bg: #18181b;
  --prompt-border: #27272a;
  --prompt-text: #e4e4e8;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.1);
  --shadow-glow: 0 0 60px rgba(168, 85, 247, 0.04);

  --gradient-accent: linear-gradient(135deg, #a855f7 0%, #3b82f6 100%);
  --gradient-accent-hover: linear-gradient(135deg, #c084fc 0%, #60a5fa 100%);
  --gradient-hero: linear-gradient(135deg, #a855f7 0%, #3b82f6 100%);
  --gradient-glow: radial-gradient(ellipse at center, rgba(168,85,247,0.08) 0%, rgba(59,130,246,0.06) 40%, transparent 70%);

  color-scheme: light;
}

/* ---- Base ---- */
body {
  font-family: var(--font);
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background var(--transition-slow), color var(--transition-slow);
}

/* ---- Header ---- */
.site-header {
  background: transparent;
  border-bottom: 1px solid var(--border-subtle);
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: color-mix(in srgb, var(--bg-base) 70%, transparent);
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: inherit;
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--gradient-accent);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  box-shadow: 0 0 20px rgba(168, 85, 247, 0.2);
}

.logo-text {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.4px;
  color: var(--text-primary);
}

.logo-text span {
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 6px;
}

.header-tagline {
  font-size: 13px;
  color: var(--text-muted);
  display: none;
  letter-spacing: -0.1px;
  margin-right: 12px;
}

@media (min-width: 768px) {
  .header-tagline { display: block; }
}

/* ---- Header Nav ---- */
.header-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.header-nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  transition: var(--transition);
  letter-spacing: -0.1px;
  padding: 6px 12px;
  border-radius: 8px;
}

.header-nav a:hover {
  color: var(--text-primary);
  background: var(--bg-hover);
}

.header-nav a.active {
  color: var(--text-primary);
}

/* ---- Theme Toggle ---- */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--border-default);
  border-radius: 10px;
  background: transparent;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 16px;
  transition: var(--transition);
  flex-shrink: 0;
}

.theme-toggle:hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
  color: var(--text-primary);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  display: none;
  line-height: 1;
}

[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* ---- Main Layout ---- */
.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px 96px;
}

/* ---- Hero ---- */
.hero {
  text-align: center;
  padding: 96px 0 48px;
  position: relative;
}

.hero-glow {
  position: absolute;
  top: -60px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 500px;
  background: var(--gradient-glow);
  filter: blur(80px);
  pointer-events: none;
  z-index: -1;
  opacity: 0.8;
}

.hero h1 {
  font-size: clamp(36px, 6vw, 64px);
  font-weight: 700;
  letter-spacing: -2px;
  line-height: 1.1;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.hero h1 span {
  background: var(--gradient-hero);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto;
  letter-spacing: -0.2px;
  line-height: 1.6;
}

/* ---- Step Indicators ---- */
.steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  margin: 32px 0 0;
  flex-wrap: wrap;
}

.step-pill {
  display: flex;
  align-items: center;
  gap: 6px;
  background: transparent;
  border: 1px solid var(--border-default);
  border-radius: 100px;
  padding: 6px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
  letter-spacing: -0.1px;
}

.step-pill.active {
  border-color: var(--border-accent);
  background: var(--accent-muted);
  color: var(--accent);
}

.step-pill.done {
  border-color: rgba(52, 211, 153, 0.3);
  background: var(--success-bg);
  color: var(--success);
}

.step-num {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: currentColor;
  color: var(--bg-base);
  font-size: 10px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  opacity: 0.3;
}

.step-pill.active .step-num,
.step-pill.done .step-num {
  opacity: 1;
}

.step-arrow {
  color: var(--text-muted);
  font-size: 12px;
  opacity: 0.4;
}

/* ---- Product Preview ---- */
.product-preview {
  max-width: 900px;
  margin: 48px auto 0;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  position: relative;
}

.product-preview-glow {
  position: absolute;
  top: -40px;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 300px;
  background: var(--gradient-glow);
  filter: blur(60px);
  pointer-events: none;
  z-index: -1;
  opacity: 0.5;
}

.preview-titlebar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-default);
  background: var(--bg-elevated);
}

.preview-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--border-strong);
}

.preview-titlebar-text {
  font-size: 12px;
  color: var(--text-muted);
  margin-left: 4px;
  font-weight: 500;
}

.preview-steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  padding: 32px 24px;
  flex-wrap: wrap;
}

.preview-step {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
}

.preview-step-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: white;
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.preview-step-label {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
  white-space: nowrap;
}

.preview-step-arrow {
  color: var(--text-muted);
  font-size: 16px;
  opacity: 0.3;
  padding: 0 4px;
}

/* ---- Section Block ---- */
.section-block {
  background: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-top: 24px;
  transition: opacity 0.2s, background var(--transition-slow), border-color var(--transition-slow);
  animation: fadeSlideIn 0.4s ease;
}

.section-block.locked {
  opacity: 0.35;
  pointer-events: none;
}

.section-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 0.6px;
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-title-num {
  width: 24px;
  height: 24px;
  border-radius: 7px;
  background: var(--gradient-accent);
  color: var(--text-on-accent);
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ---- Test Cards ---- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.test-card {
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 20px 18px;
  cursor: pointer;
  transition: all 0.2s ease;
  background: var(--bg-elevated);
  text-align: left;
  position: relative;
  overflow: hidden;
}

.test-card:hover {
  border-color: var(--border-strong);
  background: var(--bg-hover);
  transform: scale(1.01);
}

.test-card.selected {
  border-color: var(--accent);
  background: var(--accent-muted);
  box-shadow: 0 0 0 1px var(--accent), var(--shadow-glow);
}

.test-card-icon {
  font-size: 26px;
  margin-bottom: 12px;
}

.test-card-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 2px;
  letter-spacing: -0.3px;
}

.test-card-subtitle {
  font-size: 12px;
  color: var(--text-secondary);
  font-weight: 500;
}

.test-card-desc {
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 8px;
  line-height: 1.5;
}

.test-card .check {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: white;
  font-size: 10px;
  display: none;
  align-items: center;
  justify-content: center;
}

.test-card.selected .check {
  display: flex;
}

/* ---- Section / Grade Pills ---- */
.section-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.section-pill {
  border: 1px solid var(--border-default);
  border-radius: 10px;
  padding: 10px 16px;
  cursor: pointer;
  transition: all 0.2s ease;
  background: var(--bg-elevated);
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 6px;
  letter-spacing: -0.1px;
}

.section-pill:hover {
  border-color: var(--border-strong);
  color: var(--text-primary);
  background: var(--bg-hover);
  transform: scale(1.02);
}

.section-pill.selected {
  border-color: var(--accent);
  background: var(--accent-muted);
  color: var(--accent);
  font-weight: 600;
  box-shadow: 0 0 0 1px var(--accent);
}

.section-pill .pill-meta {
  font-size: 11px;
  font-weight: 400;
  color: var(--text-muted);
}

.section-pill.selected .pill-meta {
  color: color-mix(in srgb, var(--accent) 60%, transparent);
}

/* ---- LLM Cards ---- */
.llm-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.llm-card {
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 20px;
  cursor: pointer;
  transition: all 0.2s ease;
  background: var(--bg-elevated);
  position: relative;
  overflow: hidden;
}

.llm-card:hover {
  border-color: var(--border-strong);
  background: var(--bg-hover);
  transform: scale(1.01);
}

.llm-card.selected {
  box-shadow: 0 0 0 1px var(--llm-color), 0 0 30px color-mix(in srgb, var(--llm-color) 12%, transparent);
}

.llm-card[data-llm="gemini"] { --llm-color: var(--gemini-color); }
.llm-card[data-llm="chatgpt"] { --llm-color: var(--chatgpt-color); }
.llm-card[data-llm="claude"] { --llm-color: var(--claude-color); }

.llm-card:hover,
.llm-card.selected {
  border-color: var(--llm-color);
}

.llm-card.selected {
  background: color-mix(in srgb, var(--llm-color) 6%, var(--bg-elevated));
}

.llm-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 12px;
}

.llm-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 17px;
  font-weight: 900;
  color: white;
}

.llm-card[data-llm="gemini"] .llm-icon { background: var(--gemini-color); }
.llm-card[data-llm="chatgpt"] .llm-icon { background: var(--chatgpt-color); }
.llm-card[data-llm="claude"] .llm-icon { background: var(--claude-color); }

.llm-badge {
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding: 3px 8px;
  border-radius: 6px;
  white-space: nowrap;
}

.llm-badge.recommended {
  background: var(--warning-bg);
  color: var(--warning);
  border: 1px solid var(--warning-border);
}

.llm-card-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.2px;
}

.llm-card-company {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.llm-card-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.llm-strengths {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}

.strength-tag {
  font-size: 11px;
  padding: 3px 8px;
  border-radius: 6px;
  background: var(--bg-hover);
  color: var(--text-secondary);
  border: 1px solid var(--border-default);
}

.llm-card.selected .strength-tag {
  background: color-mix(in srgb, var(--llm-color) 8%, var(--bg-elevated));
  border-color: color-mix(in srgb, var(--llm-color) 20%, transparent);
  color: var(--llm-color);
}

.llm-card .check {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--llm-color);
  color: white;
  font-size: 10px;
  display: none;
  align-items: center;
  justify-content: center;
}

.llm-card.selected .check {
  display: flex;
}

/* ---- Recommendation Banner ---- */
.recommendation-banner {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  background: var(--warning-bg);
  border: 1px solid var(--warning-border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 14px;
  font-size: 13px;
  color: var(--warning);
  line-height: 1.5;
}

.recommendation-banner .icon {
  font-size: 16px;
  flex-shrink: 0;
  margin-top: 1px;
}

.recommendation-banner strong { font-weight: 600; }

.recommendation-banner a {
  color: var(--warning);
  font-weight: 600;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.recommendation-banner a:hover { opacity: 0.8; }

/* ---- Prompt Output ---- */
.prompt-output {
  margin-top: 24px;
  display: none;
}

.prompt-output.visible {
  display: block;
  animation: fadeSlideIn 0.35s ease;
}

@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

.prompt-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 16px;
}

.prompt-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
  letter-spacing: -0.2px;
}

.prompt-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.meta-tag {
  font-size: 11px;
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--bg-hover);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
  font-weight: 500;
}

.meta-tag.llm-tag[data-llm="gemini"] {
  background: color-mix(in srgb, var(--gemini-color) 10%, var(--bg-elevated));
  color: var(--gemini-color);
  border-color: color-mix(in srgb, var(--gemini-color) 20%, transparent);
}

.meta-tag.llm-tag[data-llm="chatgpt"] {
  background: color-mix(in srgb, var(--chatgpt-color) 10%, var(--bg-elevated));
  color: var(--chatgpt-color);
  border-color: color-mix(in srgb, var(--chatgpt-color) 20%, transparent);
}

.meta-tag.llm-tag[data-llm="claude"] {
  background: color-mix(in srgb, var(--claude-color) 10%, var(--bg-elevated));
  color: var(--claude-color);
  border-color: color-mix(in srgb, var(--claude-color) 20%, transparent);
}

.prompt-box {
  background: var(--prompt-bg);
  border-radius: var(--radius-lg);
  padding: 24px;
  position: relative;
  border: 1px solid var(--prompt-border);
}

.prompt-text {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--prompt-text);
  white-space: pre-wrap;
  word-break: break-word;
}

.copy-btn {
  position: absolute;
  top: 14px;
  right: 14px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  color: #71717a;
  border-radius: 8px;
  padding: 6px 14px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 5px;
  font-family: var(--font);
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  color: #d4d4d8;
}

.copy-btn.copied {
  background: rgba(52, 211, 153, 0.15);
  border-color: rgba(52, 211, 153, 0.3);
  color: #34d399;
}

.prompt-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 16px;
  flex-wrap: wrap;
}

.open-llm-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s ease;
  color: white;
  border: none;
  cursor: pointer;
  font-family: var(--font);
}

.open-llm-btn[data-llm="gemini"] { background: var(--gemini-color); }
.open-llm-btn[data-llm="chatgpt"] { background: var(--chatgpt-color); }
.open-llm-btn[data-llm="claude"] { background: var(--claude-color); }

.open-llm-btn:hover {
  filter: brightness(1.15);
  transform: translateY(-1px);
}

.copy-big-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  color: var(--text-secondary);
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font);
}

.copy-big-btn:hover {
  border-color: var(--border-strong);
  color: var(--text-primary);
  background: var(--bg-hover);
}

.copy-big-btn.copied {
  border-color: rgba(52, 211, 153, 0.3);
  color: var(--success);
  background: var(--success-bg);
}

/* ---- Instruction Card ---- */
.instructions-card {
  background: var(--accent-muted);
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-lg);
  padding: 18px 20px;
  margin-top: 18px;
  font-size: 13px;
  color: var(--accent);
  line-height: 1.6;
}

.instructions-card strong { font-weight: 600; }
.instructions-card ol { padding-left: 18px; margin-top: 8px; }
.instructions-card li { margin-bottom: 4px; }

/* ---- Reset button ---- */
.reset-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: 1px solid var(--border-default);
  color: var(--text-muted);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  padding: 8px 16px;
  border-radius: 10px;
  transition: var(--transition);
  margin-top: 16px;
  font-family: var(--font);
}

.reset-btn:hover {
  color: var(--text-secondary);
  border-color: var(--border-strong);
  background: var(--bg-hover);
}

/* ---- Footer ---- */
.site-footer {
  text-align: center;
  padding: 32px 24px;
  color: var(--text-muted);
  font-size: 13px;
  border-top: 1px solid var(--border-default);
  margin-top: 96px;
  letter-spacing: -0.1px;
}

.site-footer strong {
  color: var(--text-secondary);
}

/* ---- Experience Cards ---- */
.experience-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.experience-card {
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  cursor: pointer;
  transition: all 0.2s ease;
  background: var(--bg-elevated);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  text-align: left;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.experience-card:hover {
  border-color: var(--border-strong);
  background: var(--bg-hover);
  transform: scale(1.02);
  box-shadow: var(--shadow);
}

.experience-card.selected {
  border-color: var(--accent);
  background: var(--accent-muted);
  box-shadow: 0 0 0 1px var(--accent), var(--shadow-glow);
}

.experience-card-icon {
  font-size: 32px;
  margin-bottom: 16px;
}

.experience-card-name {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.4px;
}

.experience-card-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 18px;
}

.experience-features {
  list-style: none;
  padding: 0;
  margin: 0 0 24px 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex-grow: 1;
}

.experience-features li {
  font-size: 14px;
  color: var(--text-secondary);
  padding-left: 24px;
  position: relative;
  line-height: 1.4;
}

.experience-features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--success);
  font-weight: 700;
  font-size: 13px;
}

.experience-card-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-on-accent);
  background: var(--gradient-accent);
  transition: all 0.2s ease;
  letter-spacing: -0.1px;
  align-self: flex-start;
}

.experience-card:hover .experience-card-btn {
  filter: brightness(1.1);
  box-shadow: 0 4px 16px rgba(168, 85, 247, 0.2);
}

.experience-card.selected .experience-card-btn {
  box-shadow: 0 0 20px rgba(168, 85, 247, 0.15);
}

/* ---- Advanced Steps ---- */
.context-textarea {
  width: 100%;
  min-height: 100px;
  padding: 16px;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 14px;
  line-height: 1.6;
  resize: vertical;
  transition: var(--transition);
}

.context-textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-muted);
}

.context-textarea::placeholder { color: var(--text-muted); }

.context-hint {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 8px;
}

.questions-input-row {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 20px;
}

.questions-input {
  width: 100px;
  padding: 12px 16px;
  border: 1px solid var(--border-default);
  border-radius: var(--radius);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 16px;
  font-weight: 600;
  text-align: center;
  transition: var(--transition);
  -moz-appearance: textfield;
}

.questions-input::-webkit-inner-spin-button,
.questions-input::-webkit-outer-spin-button { opacity: 1; }

.questions-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-muted);
}

.questions-range {
  font-size: 13px;
  color: var(--text-muted);
}

.generate-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 700;
  color: var(--text-on-accent);
  background: var(--gradient-accent);
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: var(--font);
  letter-spacing: -0.2px;
}

.generate-btn:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(168, 85, 247, 0.25);
}

/* ---- About Page ---- */
.about-hero {
  text-align: center;
  padding: 96px 0 48px;
  position: relative;
}

.about-hero h1 {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -1.5px;
  line-height: 1.1;
  margin-bottom: 16px;
}

.about-hero h1 span {
  background: var(--gradient-hero);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.about-hero p {
  font-size: 18px;
  color: var(--text-secondary);
}

.about-content {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 24px;
  padding-bottom: 48px;
}

.about-section {
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  padding: 32px 28px;
}

.about-section h2 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 16px;
}

.about-section p {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.how-steps {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.how-step {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.how-step-num {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gradient-accent);
  color: var(--text-on-accent);
  font-size: 14px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.how-step strong {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  display: block;
  margin-bottom: 2px;
}

.how-step p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin: 0;
}

.supported-tests {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

.supported-test {
  text-align: center;
  padding: 20px 14px;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  background: var(--bg-elevated);
  transition: all 0.2s ease;
}

.supported-test:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow);
}

.supported-test-icon { font-size: 32px; margin-bottom: 10px; }

.supported-test strong {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-primary);
  display: block;
  margin-bottom: 6px;
}

.supported-test p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.5;
  margin: 0;
}

.about-cta {
  text-align: center;
  padding: 12px 0;
}

.about-cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 36px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-on-accent);
  background: var(--gradient-accent);
  text-decoration: none;
  transition: all 0.2s ease;
  letter-spacing: -0.2px;
}

.about-cta-btn:hover {
  filter: brightness(1.1);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(168, 85, 247, 0.25);
}

/* ---- Fade-in animation for sections ---- */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.fade-in {
  animation: fadeSlideIn 0.5s ease;
}

/* ---- Utility ---- */
.hidden { display: none !important; }

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .main-content { padding: 0 16px 60px; }
  .section-block { padding: 20px 16px; }
  .card-grid { grid-template-columns: 1fr 1fr; }
  .llm-grid { grid-template-columns: 1fr; }
  .experience-grid { grid-template-columns: 1fr; }
  .hero { padding: 64px 0 32px; }
  .hero h1 { letter-spacing: -1px; }
  .prompt-box { padding: 16px; }
  .copy-btn { position: static; margin-bottom: 10px; width: fit-content; }
  .steps { gap: 3px; }
  .step-pill { padding: 5px 10px; font-size: 12px; }
  .supported-tests { grid-template-columns: 1fr; }
  .about-section { padding: 24px 18px; }
  .header-tagline { display: none; }
  .preview-steps { gap: 0; padding: 20px 16px; }
  .preview-step { padding: 6px 8px; }
  .preview-step-label { font-size: 12px; }
  .product-preview { margin-top: 32px; }
  .about-hero { padding: 64px 0 32px; }
  .experience-card { padding: 24px 20px; }
}

@media (max-width: 480px) {
  .card-grid { grid-template-columns: 1fr; }
  .preview-step-arrow { display: none; }
  .preview-steps { flex-direction: column; align-items: flex-start; }
}