/* AI内容工厂 - 设计系统 CSS */

:root {
  --color-primary: #5B4DFF;
  --color-primary-hover: #4A3FD9;
  --color-primary-light: #EDE9FF;
  --color-neutral-900: #0F0F1A;
  --color-neutral-800: #1A1A2E;
  --color-neutral-700: #2D2D44;
  --color-neutral-600: #4A4A68;
  --color-neutral-500: #6B6B8A;
  --color-neutral-400: #8A8AA3;
  --color-neutral-300: #B8B8C8;
  --color-neutral-200: #E2E2EA;
  --color-neutral-100: #F5F5F8;
  --color-neutral-50: #FAFAFC;
  --color-success: #22C55E;
  --color-warning: #F59E0B;
  --color-error: #EF4444;
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', sans-serif;
  --font-size-h1: 56px;
  --font-size-h2: 40px;
  --font-size-h3: 28px;
  --font-size-h4: 24px;
  --font-size-h5: 20px;
  --font-size-body: 16px;
  --font-size-small: 14px;
  --spacing-section: 80px;
  --spacing-large: 48px;
  --spacing-medium: 24px;
  --spacing-small: 16px;
  --spacing-xs: 12px;
  --spacing-xxs: 8px;
  --radius-small: 4px;
  --radius-medium: 8px;
  --radius-large: 16px;
  --radius-full: 9999px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 15px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 25px rgba(0,0,0,0.15);
  --transition-normal: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: var(--font-family);
  font-size: var(--font-size-body);
  line-height: 1.5;
  color: var(--color-neutral-800);
  background: var(--color-neutral-50);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

h1 { font-size: var(--font-size-h1); }
h2 { font-size: var(--font-size-h2); }
h3 { font-size: var(--font-size-h3); }
h4 { font-size: var(--font-size-h4); }
h5 { font-size: var(--font-size-h5); }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: var(--font-size-body);
  font-weight: 600;
  border-radius: var(--radius-medium);
  border: none;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
}

.btn:hover { transform: translateY(-2px); }

.btn-primary {
  background: var(--color-primary);
  color: white;
  box-shadow: 0 4px 14px rgba(91, 77, 255, 0.4);
}

.btn-primary:hover {
  background: var(--color-primary-hover);
  box-shadow: 0 6px 20px rgba(91, 77, 255, 0.5);
}

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

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

.btn-sm { padding: 8px 16px; font-size: var(--font-size-small); }
.btn-lg { padding: 16px 32px; font-size: var(--font-size-h5); }
.btn-xl { padding: 18px 36px; font-size: 18px; }
.btn-block { width: 100%; }

/* 卡片 */
.card {
  background: white;
  border-radius: var(--radius-large);
  padding: var(--spacing-medium);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

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

/* 导航 */
.navbar {
  background: white;
  box-shadow: var(--shadow-sm);
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 24px;
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.navbar-nav a {
  text-decoration: none;
  color: var(--color-neutral-600);
  font-weight: 500;
  transition: color 0.2s;
}

.navbar-nav a:hover,
.navbar-nav a.active {
  color: var(--color-primary);
}

/* 表单 */
.form-group { margin-bottom: var(--spacing-small); }

.form-label {
  display: block;
  margin-bottom: 8px;
  font-size: var(--font-size-small);
  font-weight: 500;
  color: var(--color-neutral-700);
}

.form-input,
.form-textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: var(--font-size-body);
  border: 2px solid var(--color-neutral-200);
  border-radius: var(--radius-medium);
  background: white;
  transition: all var(--transition-normal);
  font-family: inherit;
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-textarea {
  min-height: 200px;
  resize: vertical;
}

/* 提示条 */
.tip-bar {
  background: linear-gradient(135deg, var(--color-warning-light) 0%, #FEF9C3 100%);
  border: 1px solid var(--color-warning);
  border-radius: var(--radius-medium);
  padding: 12px 16px;
  font-size: var(--font-size-small);
  color: #92400e;
  margin-bottom: var(--spacing-medium);
}

/* 平台标签 */
.platform-tag {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 500;
}

.platform-tag.xiaohongshu { background: #FFE4E8; color: #FF2442; }
.platform-tag.wechat { background: #E8F5E9; color: #07C160; }
.platform-tag.zhihu { background: #E3F2FD; color: #0084FF; }
.platform-tag.douyin { background: #F5F5F5; color: #333; }

/* Footer */
.footer {
  background: var(--color-neutral-900);
  color: var(--color-neutral-400);
  padding: 48px 0 24px;
  font-size: var(--font-size-small);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand {
  font-size: 20px;
  font-weight: 700;
  color: white;
  margin-bottom: 12px;
}

.footer-desc {
  color: var(--color-neutral-500);
  line-height: 1.7;
}

.footer-links h4 {
  font-size: var(--font-size-small);
  font-weight: 600;
  color: white;
  margin-bottom: 16px;
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: 8px;
}

.footer-links a {
  color: var(--color-neutral-500);
  text-decoration: none;
}

.footer-links a:hover { color: white; }

.footer-bottom {
  border-top: 1px solid var(--color-neutral-800);
  padding-top: 24px;
  text-align: center;
}

.footer-bottom a {
  color: var(--color-neutral-500);
  text-decoration: none;
}

/* 响应式 */
@media (max-width: 991px) {
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 767px) {
  h1 { font-size: 36px; }
  h2 { font-size: 28px; }
  
  .navbar-nav { display: none; }
  
  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }
}
/* 移动端优化补丁 */
@media (max-width: 768px) {
    .container { padding: 0 15px; }
    .hero { padding: 80px 0 60px; }
    .hero h1 { font-size: 28px; }
    .hero p { font-size: 16px; }
    .platform-grid { grid-template-columns: repeat(2, 1fr); gap: 15px; }
    .pricing-grid { grid-template-columns: 1fr; }
    .btn-xl { width: 100%; }
    nav .container { flex-wrap: wrap; }
    nav a { padding: 8px 12px; font-size: 14px; }
    .card { padding: 20px; }
    .stat-card { padding: 15px; }
    .stat-card .number { font-size: 24px; }
    table { font-size: 14px; }
    th, td { padding: 8px; }
    .form-group input, .form-group textarea { font-size: 16px; }
}