/* Ai管家 Website Styles - Light Theme */
@import url('https://cdn.jsdelivr.net/npm/tailwindcss@2.2.19/dist/tailwind.min.css');

/* Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Noto+Sans+SC:wght@400;500;600;700&display=swap');

/* CSS Variables */
:root {
  /* Primary Colors — sky / blue accent */
  --primary-50: #F4FBF8;
  --primary-100: #E8F8F1;
  --primary-200: #bae6fd;
  --primary-300: #7dd3fc;
  --primary-400: #6EF5C4;
  --primary-500: #177A59;
  --primary-600: #20D492;
  --primary-700: #14A873;
  --primary-800: #075985;
  --primary-900: #0c4a6e;

  /* Background Colors — light blue gradient theme */
  --bg-primary: #ffffff;
  --bg-secondary: #F0FDF4;
  --bg-tertiary: #E8F8F1;
  --bg-hero: #F5F5F5;

  /* Text Colors */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  --text-muted: #cbd5e1;

  /* Border Colors */
  --border-light: #e2e8f0;
  --border-medium: #cbd5e1;

  /* Shadow */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --shadow-glow: 0 0 40px -10px var(--primary-300);

  /* Typography */
  --font-sans: 'Inter', 'Noto Sans SC', system-ui, -apple-system, sans-serif;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: linear-gradient(180deg, #E8F8F1 0%, #F4FBF8 35%, #ffffff 100%);
  background-attachment: fixed;
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

/* Navigation Styles */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  background-color: rgba(240, 249, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition-base);
}

.navbar.scrolled {
  box-shadow: var(--shadow-md);
}

.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.9375rem;
  padding: 0.5rem 0.75rem;
  border-radius: 0.5rem;
  transition: var(--transition-fast);
  text-decoration: none;
}

.nav-link:hover {
  color: var(--primary-700);
  background-color: var(--primary-100);
}

.nav-link.active {
  color: var(--primary-700);
  background-color: var(--primary-100);
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-primary);
}

.mobile-menu {
  display: none;
  padding: 1rem;
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-light);
}

.mobile-menu.active {
  display: block;
}

@media (max-width: 768px) {
  .mobile-menu-btn {
    display: block;
  }
  .nav-links {
    display: none;
  }
}

/* Hero Section */
.hero-section {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 5rem;
}

.hero-section.hero-has-bg {
  background: var(--hero-dark-bg) !important;
}

.hero-section::before {
  display: none;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  line-height: 1.1;
  background: linear-gradient(135deg, var(--primary-600) 0%, var(--primary-500) 50%, var(--primary-400) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(1.25rem, 2.5vw, 1.5rem);
  color: var(--text-secondary);
  margin-top: 1rem;
  max-width: 600px;
}

.hero-description {
  font-size: 1.125rem;
  color: var(--text-tertiary);
  margin-top: 1.5rem;
  max-width: 560px;
  line-height: 1.7;
}

/* Buttons */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--primary-500) 0%, var(--primary-600) 100%);
  color: white;
  font-weight: 600;
  padding: 0.875rem 1.75rem;
  border-radius: 0.75rem;
  border: none;
  cursor: pointer;
  transition: var(--transition-base);
  text-decoration: none;
  box-shadow: 0 4px 14px 0 rgba(32, 212, 146, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(32, 212, 146, 0.28);
  filter: brightness(1.05);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-weight: 600;
  padding: 0.875rem 1.75rem;
  border-radius: 0.75rem;
  border: 1px solid var(--border-light);
  cursor: pointer;
  transition: var(--transition-base);
  text-decoration: none;
}

.btn-secondary:hover {
  background-color: var(--bg-secondary);
  border-color: var(--border-medium);
  transform: translateY(-2px);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background-color: transparent;
  color: var(--text-secondary);
  font-weight: 500;
  padding: 0.75rem 1.25rem;
  border-radius: 0.75rem;
  border: none;
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
}

.btn-ghost:hover {
  color: var(--primary-700);
  background-color: var(--primary-100);
}

/* Feature Cards */
.feature-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-light);
  border-radius: 1rem;
  padding: 1.5rem;
  transition: var(--transition-base);
  text-decoration: none;
  color: inherit;
  display: block;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-200);
}

.feature-icon {
  width: 3rem;
  height: 3rem;
  border-radius: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}

/* Section Styles */
.section {
  padding: 5rem 1rem;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

/* Screenshot Carousel */
.screenshot-container {
  position: relative;
  border-radius: 1rem;
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--border-light);
}

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

/* Download Cards */
.download-card {
  background-color: var(--bg-primary);
  border: 2px solid var(--border-light);
  border-radius: 1rem;
  padding: 2rem;
  text-align: center;
  transition: var(--transition-base);
}

.download-card.featured {
  border-color: var(--primary-300);
  box-shadow: var(--shadow-glow);
}

.download-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.platform-icon {
  width: 4rem;
  height: 4rem;
  background-color: var(--bg-secondary);
  border-radius: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
}

/* 主站统一页脚样式由 /css/main.css 与 /css/gptbots-style.css 提供（见 #qqai-site-footer） */

/* Language Switcher */
.lang-switch {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  background-color: var(--bg-secondary);
  padding: 0.25rem;
  border-radius: 0.5rem;
}

.lang-btn {
  padding: 0.375rem 0.75rem;
  border-radius: 0.375rem;
  border: none;
  background: none;
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition-fast);
}

.lang-btn.active {
  background-color: var(--bg-primary);
  color: var(--primary-700);
  box-shadow: var(--shadow-sm);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.toast {
  background-color: var(--text-primary);
  color: white;
  padding: 0.875rem 1.25rem;
  border-radius: 0.75rem;
  box-shadow: var(--shadow-lg);
  animation: slideIn 0.3s ease, fadeOut 0.3s ease 2.7s;
}

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes fadeOut {
  to {
    opacity: 0;
  }
}

/* Grid Layouts */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1280px) {
  .features-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* Container */
.container {
  width: 100%;
  max-width: none;
  margin: 0 auto;
  padding: 0 clamp(16px, 3vw, 48px);
}

@media (min-width: 640px) {
  .container {
    padding: 0 clamp(20px, 3.5vw, 56px);
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 clamp(24px, 5vw, 80px);
  }
}

/* Animation Utilities */
.animate-float {
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-10px);
  }
}

.animate-pulse-glow {
  animation: pulse-glow 4s ease-in-out infinite;
}

@keyframes pulse-glow {
  0%, 100% {
    opacity: 0.5;
    transform: scale(1);
  }
  50% {
    opacity: 0.8;
    transform: scale(1.05);
  }
}

/* Gradient Text */
.gradient-text {
  background: linear-gradient(135deg, var(--primary-600) 0%, var(--primary-500) 50%, var(--primary-400) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Badge */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-primary {
  background-color: var(--primary-100);
  color: var(--primary-700);
}

.badge-secondary {
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
}

/* Code Block */
.code-block {
  background-color: #1e293b;
  color: #e2e8f0;
  padding: 1rem;
  border-radius: 0.75rem;
  font-family: 'Monaco', 'Menlo', monospace;
  font-size: 0.875rem;
  overflow-x: auto;
}

/* Utility Classes */
.text-balance {
  text-wrap: balance;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Section surfaces: blend white content areas into site blue gradient */
.section.bg-white {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.97) 0%, #F4FBF8 100%);
}