:root {
  --primary-color: #007AFF;
  --secondary-color: #5AC8FA;
  --accent-color: #FFD60A;
  --background-color: #F5F5F7;
  --surface-color: #FFFFFF;
  --text-primary: #1D1D1F;
  --text-secondary: #86868B;
  --border-color: #D2D2D7;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --spacing-unit: 8px;
  --border-radius: 12px;
  --max-width: 1200px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --background-color: #000000;
    --surface-color: #1C1C1E;
    --text-primary: #F5F5F7;
    --text-secondary: #86868B;
    --border-color: #424245;
  }
}

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

body {
  font-family: var(--font-family);
  background-color: var(--background-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

a:hover {
  opacity: 0.8;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
header {
  background-color: rgba(255, 255, 255, 0.8);
  border-bottom: 1px solid var(--border-color);
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

@media (prefers-color-scheme: dark) {
  header {
    background-color: rgba(28, 28, 30, 0.8);
  }
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 700;
  font-size: 24px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-image {
  height: 32px;
  width: 32px;
  object-fit: contain;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  font-weight: 500;
  font-size: 15px;
  color: var(--text-secondary);
}

.nav-links a:hover {
  color: var(--text-primary);
}

.nav-links .cta-button {
  background-color: var(--primary-color);
  color: white;
  padding: 8px 18px;
  border-radius: 20px;
}

.nav-links .cta-button:hover {
  opacity: 0.9;
}

/* Language Selector */
.lang-selector {
  position: relative;
  display: inline-block;
}

.lang-selector-toggle {
  padding: 6px 12px !important;
  border-radius: 6px;
  background-color: rgba(0, 122, 255, 0.1);
  color: var(--primary-color) !important;
  font-weight: 500 !important;
  transition: all 0.2s;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
}

.lang-selector-toggle:hover {
  background-color: rgba(0, 122, 255, 0.2);
  opacity: 1 !important;
}

.lang-selector-toggle::after {
  content: "▼";
  font-size: 10px;
  opacity: 0.7;
}

.lang-selector-menu {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  min-width: 120px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.2s ease;
  z-index: 1000;
}

.lang-selector:hover .lang-selector-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.lang-selector-menu a {
  display: block;
  padding: 10px 16px;
  color: var(--text-primary) !important;
  font-size: 14px;
  font-weight: 400 !important;
  transition: background-color 0.2s;
  border-radius: 6px;
  margin: 4px;
}

.lang-selector-menu a:hover {
  background-color: rgba(0, 122, 255, 0.1);
  opacity: 1 !important;
}

.lang-selector-menu a.current {
  color: var(--primary-color) !important;
  font-weight: 600 !important;
  background-color: rgba(0, 122, 255, 0.05);
}

/* Hero Section */
.hero {
  text-align: center;
  padding: 80px 0 40px;
}

.hero-logo {
  width: 120px;
  height: 120px;
  margin: 0 auto 40px;
  display: block;
  filter: drop-shadow(0 10px 30px rgba(0, 122, 255, 0.15));
}

.hero h1 {
  font-size: 56px;
  line-height: 1.1;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

.hero .subtitle {
  font-size: 28px;
  line-height: 1.4;
  color: var(--text-secondary);
  margin-bottom: 40px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
  font-weight: 400;
}

.hero-buttons {
  display: flex;
  justify-content: center;
  gap: 20px;
  align-items: center;
  flex-wrap: wrap;
}

.app-store-badge {
  height: 48px;
  transition: opacity 0.2s;
}

.app-store-badge:hover {
  opacity: 0.8;
}

.app-store-badge.light {
  display: block;
}

.app-store-badge.dark {
  display: none;
}

@media (prefers-color-scheme: dark) {
  .app-store-badge.light {
    display: none;
  }

  .app-store-badge.dark {
    display: block;
  }
}

.button {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 980px;
  font-size: 17px;
  font-weight: 600;
  text-align: center;
  transition: all 0.2s;
}

.button-secondary {
  background-color: transparent;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.button-secondary:hover {
  background-color: rgba(0, 122, 255, 0.1);
}

/* Screenshot Showcase */
.screenshot-showcase {
  padding: 60px 0;
}

.screenshot-showcase h2 {
  font-size: 40px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 50px;
  letter-spacing: -0.01em;
}

.screenshot-container {
  max-width: 900px;
  margin: 0 auto 80px;
  text-align: center;
}

.screenshot-container:last-child {
  margin-bottom: 0;
}

.screenshot-container h3 {
  font-size: 32px;
  font-weight: 600;
  margin-bottom: 15px;
}

.screenshot-container p {
  font-size: 20px;
  color: var(--text-secondary);
  margin-bottom: 30px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.screenshot-wrapper {
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.screenshot-wrapper img {
  width: 100%;
  height: auto;
  display: block;
}

.screenshot-wrapper img.light-mode {
  display: block;
}

.screenshot-wrapper img.dark-mode {
  display: none;
}

@media (prefers-color-scheme: dark) {
  .screenshot-wrapper img.light-mode {
    display: none;
  }

  .screenshot-wrapper img.dark-mode {
    display: block;
  }
}

/* Features Grid */
.features {
  padding: 80px 0;
  background-color: var(--surface-color);
}

.features h2 {
  font-size: 40px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 60px;
  letter-spacing: -0.01em;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 40px;
}

.feature-card {
  text-align: center;
  padding: 30px 20px;
}

.feature-icon {
  font-size: 48px;
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 24px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.feature-card p {
  font-size: 17px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Help/Doc Page */
.doc-content {
  padding: 60px 0;
  max-width: 800px;
  margin: 0 auto;
}

.doc-content h1 {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 40px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.doc-content h2 {
  font-size: 32px;
  font-weight: 600;
  margin-top: 50px;
  margin-bottom: 20px;
}

.doc-content h3 {
  font-size: 24px;
  font-weight: 600;
  margin-top: 30px;
  margin-bottom: 15px;
}

.doc-content ul {
  padding-left: 24px;
  margin-bottom: 20px;
}

.doc-content li {
  margin-bottom: 10px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.doc-content p {
  margin-bottom: 20px;
  color: var(--text-secondary);
  font-size: 17px;
  line-height: 1.7;
}

.doc-content strong {
  color: var(--text-primary);
  font-weight: 600;
}

.doc-content code {
  background-color: rgba(0, 0, 0, 0.05);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'SF Mono', Monaco, 'Courier New', monospace;
  font-size: 0.9em;
}

.pro-badge {
  height: 20px;
  vertical-align: middle;
  margin-left: 6px;
  margin-right: 4px;
  display: inline-block;
}

@media (prefers-color-scheme: dark) {
  .doc-content code {
    background-color: rgba(255, 255, 255, 0.1);
  }
}

/* Footer */
footer {
  background-color: var(--surface-color);
  padding: 40px 0;
  margin-top: 80px;
  border-top: 1px solid var(--border-color);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-secondary);
  font-size: 14px;
  flex-wrap: wrap;
  gap: 20px;
}

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 14px;
}

.footer-links a:hover {
  color: var(--text-primary);
}

/* Responsive Design */
@media (max-width: 768px) {
  .hero-logo {
    width: 80px;
    height: 80px;
    margin-bottom: 30px;
  }

  .hero h1 {
    font-size: 40px;
  }

  .hero .subtitle {
    font-size: 22px;
  }

  .screenshot-showcase h2,
  .features h2 {
    font-size: 32px;
  }

  .screenshot-container h3 {
    font-size: 26px;
  }

  .screenshot-container p {
    font-size: 18px;
  }

  .nav-links {
    gap: 16px;
  }

  .footer-content {
    flex-direction: column;
    text-align: center;
  }
}