/* ========================================
   甬战全站基础样式
   所有产品页面统一引用，保证视觉一致
   ======================================== */

/* CSS变量 - 主题色 */
:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #f1f3f5;
  --text-primary: #1a1a2e;
  --text-secondary: #4a5568;
  --text-tertiary: #718096;
  --border-color: #e2e8f0;
  --border-light: #edf2f7;
  --accent-primary: #6366f1;
  --accent-hover: #4f46e5;
  --accent-light: #eef2ff;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.08);
  --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.1);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --header-height: 64px;
  --max-width: 1200px;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-tertiary: #94a3b8;
  --border-color: #334155;
  --border-light: #1e293b;
  --accent-primary: #818cf8;
  --accent-hover: #a5b4fc;
  --accent-light: #312e81;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.4);
  --shadow-lg: 0 10px 25px -5px rgba(0,0,0,0.5);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  transition: background-color 0.3s ease, color 0.3s ease;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-primary);
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
  color: inherit;
}

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

/* 通用按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent-primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background: var(--border-light);
}

/* 卡片 */
.card {
  background: var(--bg-primary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.card:hover {
  box-shadow: var(--shadow-md);
}

/* 回到顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent-primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all 0.3s ease;
  box-shadow: var(--shadow-lg);
  z-index: 999;
  border: none;
  font-size: 18px;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
}

/* 页面内容区 - 适配fixed header */
.main,
.main-content,
.hero,
.page-content {
  padding-top: calc(var(--header-height) + 20px);
}

@media (max-width: 768px) {
  .main,
  .main-content,
  .hero,
  .page-content {
    padding-top: calc(var(--header-height) + 12px);
  }
}

/* 响应式 */
@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }
}