/* ===================================
   搭子旅行 官网 - 全局样式
   =================================== */

/* ===== 设计令牌 ===== */
:root {
  /* 品牌色 - 青柠绿系，清爽旅行风 */
  --primary: #7CB342;
  --primary-light: #AED581;
  --primary-dark: #558B2F;
  --primary-bg: #F1F8E9;
  --primary-glow: rgba(124, 179, 66, 0.15);

  /* 功能色 - 旅行主题 */
  --secondary: #37474F;
  --accent: #26A69A;
  --accent-light: #80CBC4;
  --accent-bg: #E0F2F1;
  --warning: #FFA726;
  --danger: #EF5350;
  --info: #42A5F5;
  --purple: #7E57C2;

  /* 中性色 */
  --bg: #FFFFFF;
  --bg-soft: #FAFBFC;
  --bg-muted: #F0F2F5;
  --bg-dark: #0F1923;
  --bg-dark-soft: #1A2B3C;

  /* 文字色 */
  --text: #1A2B3C;
  --text-secondary: #5A6B7D;
  --text-muted: #9AABB8;
  --text-inverse: #FFFFFF;

  /* 边框 */
  --border: #E4E8EC;
  --border-light: #F0F2F5;

  /* 阴影 */
  --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.1);
  --shadow-xl: 0 16px 60px rgba(0,0,0,0.14);
  --shadow-primary: 0 8px 30px rgba(124, 179, 66, 0.25);
  --shadow-glass: 0 8px 32px rgba(0,0,0,0.06);

  /* 圆角 */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;

  /* 排版 */
  --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-display: 'Inter', 'Noto Sans SC', sans-serif;

  /* 布局 */
  --container: 1200px;
  --container-wide: 1400px;
  --nav-height: 72px;
  --nav-height-mobile: 60px;

  /* 动效 */
  --ease-out: cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
  --duration-fast: 0.2s;
  --duration-normal: 0.35s;
  --duration-slow: 0.6s;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--duration-fast) var(--ease-smooth);
}

ul, ol { list-style: none; }

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

button, input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  border: none;
  outline: none;
  background: none;
}

button { cursor: pointer; }

::selection {
  background: var(--primary);
  color: #fff;
}

/* ===== 容器 ===== */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

.container--wide {
  max-width: var(--container-wide);
}

/* ===== 排版 ===== */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.25;
  color: var(--text);
}

.text-gradient {
  background: linear-gradient(135deg, var(--primary) 0%, #26A69A 50%, #42A5F5 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }

/* ===== 间距工具 ===== */
.section {
  padding: 100px 0;
}

.section--sm {
  padding: 72px 0;
}

.section--lg {
  padding: 120px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 18px;
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  background: var(--primary-bg);
  border-radius: var(--radius-full);
  margin-bottom: 18px;
  letter-spacing: 0.3px;
}

.section-title {
  font-size: 40px;
  font-weight: 900;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}

.section-desc {
  font-size: 17px;
  color: var(--text-secondary);
  max-width: 580px;
  margin: 0 auto;
  line-height: 1.75;
}

/* ===== 动画基础 ===== */
.fade-up {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity var(--duration-slow) var(--ease-out),
              transform var(--duration-slow) var(--ease-out);
}

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

.fade-up-delay-1 { transition-delay: 0.1s; }
.fade-up-delay-2 { transition-delay: 0.2s; }
.fade-up-delay-3 { transition-delay: 0.3s; }
.fade-up-delay-4 { transition-delay: 0.4s; }
.fade-up-delay-5 { transition-delay: 0.5s; }

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

@keyframes pulse-glow {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}

@keyframes spin-slow {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* ===== 响应式断点 ===== */
@media (max-width: 1024px) {
  .section { padding: 80px 0; }
  .section--lg { padding: 100px 0; }
  .section-title { font-size: 34px; }
  .section-header { margin-bottom: 48px; }
}

@media (max-width: 768px) {
  :root {
    --nav-height: var(--nav-height-mobile);
  }
  .container { padding: 0 16px; }
  .section { padding: 60px 0; }
  .section--lg { padding: 80px 0; }
  .section-title { font-size: 28px; }
  .section-desc { font-size: 15px; }
  .section-header { margin-bottom: 36px; }
}