/* ===== CSS Variables (from extension design system) ===== */
:root {
  --bg-primary: #f5f6fa;
  --bg-secondary: #edeef3;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8f9fc;

  --teal: #0d9488;
  --teal-dim: rgba(13, 148, 136, 0.08);
  --teal-glow: rgba(13, 148, 136, 0.15);
  --third-party: #2563eb;

  --text-primary: #1a1a2e;
  --text-secondary: #5a6078;
  --text-muted: #9ca3b8;

  --border: rgba(0, 0, 0, 0.08);
  --border-light: rgba(0, 0, 0, 0.12);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 20px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08), 0 2px 4px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.1), 0 4px 8px rgba(0, 0, 0, 0.05);

  --font: "Inter", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", ui-monospace, monospace;
}

/* ===== Reset & Base ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
}

a {
  color: var(--teal);
  text-decoration: none;
  transition: opacity 0.2s ease;
}

a:hover {
  opacity: 0.8;
}

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

/* ===== Layout ===== */
.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Animations ===== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@keyframes scaleIn {
  from { opacity: 0; transform: scale(0.85); }
  to { opacity: 1; transform: scale(1); }
}

.fade-in-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Hero ===== */
.hero {
  text-align: center;
  padding: 100px 0 80px;
}

.hero-icon {
  width: 200px;
  height: auto;
  margin-bottom: 32px;
  margin-left: 52px;
  animation: scaleIn 0.7s cubic-bezier(0.34, 1.56, 0.64, 1) both;
}

.hero h1 {
  font-size: 60px;
  font-weight: 800;
  letter-spacing: -1.5px;
  margin-bottom: 12px;
  color: var(--text-primary);
  animation: fadeInUp 0.6s ease 0.15s both;
}

.hero-tagline {
  font-size: 24px;
  color: var(--text-secondary);
  margin-bottom: 32px;
  animation: fadeInUp 0.6s ease 0.25s both;
}

.hero-usps {
  list-style: none;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 10px 28px;
  font-size: 17px;
  color: var(--text-muted);
  margin-bottom: 48px;
  animation: fadeInUp 0.6s ease 0.35s both;
}

.hero-usps li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.hero-usps li::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
  flex-shrink: 0;
}

/* ===== CTA Button ===== */
.cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 16px 40px;
  background: var(--teal);
  color: #ffffff;
  font-size: 18px;
  font-weight: 600;
  font-family: var(--font);
  border: none;
  border-radius: var(--radius-xl);
  cursor: pointer;
  transition: all 0.25s ease;
  box-shadow: 0 2px 8px var(--teal-glow);
  text-decoration: none;
}

.hero .cta-btn {
  animation: fadeInUp 0.6s ease 0.45s both;
}

.cta-btn:hover {
  opacity: 0.9;
  transform: translateY(-2px);
  box-shadow: 0 4px 16px var(--teal-glow);
}

.cta-btn:active {
  transform: translateY(0);
}

/* ===== Section Shared ===== */
section {
  padding: 64px 0;
}

section h2 {
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
}

/* ===== About ===== */
.about {
  text-align: center;
  border-top: 1px solid var(--border);
}

.about p {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto;
}

/* ===== Screenshot ===== */
.screenshot {
  padding: 0 0 64px;
  margin-top: -20px;
}

.screenshot .container {
  max-width: 1200px;
  padding: 0 24px;
}

.screenshot-img {
  width: 100%;
  display: block;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  transition: all 0.3s ease;
}

.screenshot-img:hover {
  transform: translateY(-3px);
  box-shadow: 0 14px 40px rgba(0, 0, 0, 0.14), 0 6px 12px rgba(0, 0, 0, 0.06);
}

/* ===== Features ===== */
.features {
  border-top: 1px solid var(--border);
}

.features h2 {
  text-align: center;
  margin-bottom: 40px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px 24px;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-sm);
}

.feature-card:hover {
  border-color: var(--border-light);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.feature-emoji {
  font-size: 32px;
  display: block;
  margin-bottom: 12px;
  text-align: center;
}

.feature-card h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-primary);
  text-align: center;
}

.feature-card p {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-secondary);
}

/* ===== FAQ ===== */
.faq {
  border-top: 1px solid var(--border);
}

.faq h2 {
  text-align: center;
  margin-bottom: 40px;
}

.faq-list {
  max-width: 680px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.faq-list details {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: box-shadow 0.3s ease, border-color 0.3s ease;
}

.faq-list details[open] {
  box-shadow: var(--shadow-sm);
  border-color: var(--border-light);
}

.faq-list details[open] summary {
  border-bottom: 1px solid var(--border);
}

.faq-list summary {
  padding: 18px 24px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  color: var(--text-primary);
  transition: background 0.2s ease;
}

.faq-list summary:hover {
  background: var(--bg-card-hover);
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  content: "+";
  font-size: 20px;
  font-weight: 300;
  color: var(--text-muted);
  flex-shrink: 0;
  transition: transform 0.2s ease;
}

.faq-list details[open] summary::after {
  content: "\2212";
}

.faq-answer {
  padding: 12px 24px 20px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
  animation: faqReveal 0.3s ease both;
}

@keyframes faqReveal {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Open Source ===== */
.open-source {
  text-align: center;
  border-top: 1px solid var(--border);
}

.open-source p {
  font-size: 17px;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.github-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  color: var(--text-primary);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s ease;
  box-shadow: var(--shadow-sm);
}

.github-btn:hover {
  border-color: var(--border-light);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  opacity: 1;
}

.github-btn svg {
  width: 20px;
  height: 20px;
}

/* ===== Bottom CTA ===== */
.bottom-cta {
  text-align: center;
  border-top: 1px solid var(--border);
}

.bottom-cta h2 {
  margin-bottom: 24px;
}

.bottom-cta-buttons {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* ===== Footer ===== */
.site-footer {
  padding: 32px 0;
  text-align: center;
  border-top: 1px solid var(--border);
  font-size: 14px;
  color: var(--text-muted);
}

.site-footer a {
  color: var(--text-secondary);
  text-decoration: underline;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero {
    padding: 72px 0 56px;
  }

  .hero-icon {
    width: 150px;
    height: auto;
  }

  .hero h1 {
    font-size: 42px;
  }

  .hero-tagline {
    font-size: 20px;
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  section h2 {
    font-size: 28px;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 32px;
  }

  .hero-icon {
    width: 130px;
    height: auto;
  }

  .hero-usps {
    flex-direction: column;
    align-items: center;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .cta-btn {
    width: 100%;
    justify-content: center;
  }

  section {
    padding: 48px 0;
  }
}