/* 公共样式（从 style.css 提取） */
body { font-family: 'Segoe UI', Arial, Helvetica, sans-serif; background: #f7f9fb; color: #222; margin: 0; }
.header { 
  background: #4285f4;
  color: #fff;
  padding: 36px 0 32px 0;
  box-shadow: 0 4px 20px rgba(79,195,247,0.25);
  position: relative;
  overflow: hidden;
}
.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(circle at 20% 50%, rgba(255,255,255,0.15) 0%, transparent 50%),
              radial-gradient(circle at 80% 80%, rgba(255,255,255,0.1) 0%, transparent 50%);
  pointer-events: none;
}
.header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
}
/* Header顶部区域 */
.header-top {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: relative;
  z-index: 1;
  min-height: 70px;
}
.header-left { flex: 1; }
.header-right { flex-shrink: 0; }
.logo-link { text-decoration: none; color: inherit; display: inline-block; }
.logo { display: flex; align-items: center; gap: 16px; transition: transform 0.2s; }
.logo:hover { transform: translateX(2px); }
.logo-icon { width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; background: rgba(255,255,255,0.15); border-radius: 10px; color: rgba(255,255,255,0.95); flex-shrink: 0; backdrop-filter: blur(10px); box-shadow: 0 2px 8px rgba(0,0,0,0.1); transition: all 0.3s; }
.logo:hover .logo-icon { background: rgba(255,255,255,0.2); transform: rotate(5deg); }
.logo-icon svg { width: 24px; height: 24px; }
.logo-text h1 { margin: 0; font-size: 1.75rem; letter-spacing: 0.3px; font-weight: 700; text-shadow: 0 2px 10px rgba(0,0,0,0.15); line-height: 1.3; color: #fff; }
.logo-text p { margin: 3px 0 0 0; font-size: 0.88rem; opacity: 0.92; font-weight: 400; text-shadow: 0 1px 5px rgba(0,0,0,0.1); color: #fff; }
.header-nav { display: flex; gap: 8px; align-items: center; }
.nav-link { color: #fff; text-decoration: none; padding: 10px 20px; border-radius: 22px; font-size: 0.94rem; font-weight: 500; transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); background: rgba(255,255,255,0.15); border: 1px solid rgba(255,255,255,0.25); backdrop-filter: blur(12px); box-shadow: 0 2px 8px rgba(0,0,0,0.08); white-space: nowrap; }
.nav-link:hover { background: rgba(255,255,255,0.25); border-color: rgba(255,255,255,0.35); transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,0.15); }
.nav-link.active { background: rgba(255,255,255,0.3); border-color: rgba(255,255,255,0.45); font-weight: 600; box-shadow: 0 2px 10px rgba(0,0,0,0.12); }
.header-search { max-width: 1080px; margin: 24px auto 0 auto; padding: 0 32px; position: relative; z-index: 1; }
/* 分类导航 */
.category-nav { background: #fff; border-bottom: 1px solid #e0e7f0; padding: 18px 0; margin-bottom: 24px; box-shadow: 0 2px 8px rgba(0,0,0,0.04); position: sticky; top: 0; z-index: 100; }
.category-container { max-width: 1080px; margin: 0 auto; padding: 0 32px; display: flex; gap: 12px; flex-wrap: wrap; }
.category-btn { background: #f8fbff; border: 1px solid #d3e7ff; color: #4285f4; padding: 8px 20px; border-radius: 20px; font-size: 0.95rem; cursor: pointer; transition: all 0.2s; font-family: inherit; text-decoration: none; display: inline-block; }
.category-btn:hover { background: #e3f1fa; border-color: #4285f4; }
.category-btn.active { background: #4285f4; color: #fff; border-color: #4285f4; font-weight: 500; }
.category-section { margin-bottom: 40px; }
.category-section:last-child { margin-bottom: 0; }
.category-title { color: #4285f4; font-size: 1.3rem; margin: 0 0 20px 0; padding-bottom: 12px; border-bottom: 2px solid #e3f1fa; font-weight: 600; }
.search-form { margin: 0; padding: 0; }
.search-box-wrapper { display: flex; align-items: center; max-width: 600px; margin: 0 auto; background: rgba(255,255,255,0.98); border: 2px solid rgba(255,255,255,0.4); border-radius: 50px; padding: 6px 6px 6px 22px; transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); backdrop-filter: blur(12px); box-shadow: 0 2px 12px rgba(0,0,0,0.1); }
.search-box-wrapper:focus-within { border-color: rgba(255,255,255,0.9); box-shadow: 0 6px 24px rgba(0,0,0,0.25), 0 0 0 4px rgba(255,255,255,0.2); background: #fff; transform: translateY(-1px); }
.search-input { flex: 1; border: none; outline: none; font-size: 16px; padding: 10px 10px; background: transparent; color: #333; font-weight: 400; }
.search-input::placeholder { color: #999; font-weight: 400; }
.search-btn { background: #4285f4; border: none; border-radius: 50%; width: 42px; height: 42px; display: flex; align-items: center; justify-content: center; cursor: pointer; color: #fff; transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); flex-shrink: 0; box-shadow: 0 2px 8px rgba(66,133,244,0.3); }
.search-btn:hover { background: linear-gradient(135deg, #2568d6, #2d8f47); transform: scale(1.08); box-shadow: 0 4px 12px rgba(66,133,244,0.4); }
.search-btn:active { transform: scale(0.96); }
/* 主体与通用排版 */
.main { max-width: 1080px; background: #fff; margin: 32px auto 0 auto; border-radius: 9px; box-shadow: 0 2px 18px rgba(0,0,0,0.07); padding: 36px 32px 48px 32px; }
h2 { color: #4285f4; border-left: 4px solid #4285f4; padding-left:12px; font-size:1.35rem; margin-bottom:14px; }
.content { font-size: 1.13rem; line-height: 1.85; }
.footer { text-align: center; color: #888; padding: 32px 0 17px 0; font-size: 1rem; margin-top: 60px; }
@media (max-width: 600px) { .main { padding: 20px 7px 40px 7px; } .header { padding: 32px 0 24px 0; } .header h1 { font-size: 1.9rem; } .header p { font-size: 0.95rem; } }
/* 工具卡片网格与卡片 */
.tools-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; margin: 32px 0; }
.tool-card { background: linear-gradient(135deg, #f8fbff 0%, #f0f7ff 100%); border: 2px solid #d3e7ff; border-radius: 12px; padding: 32px 24px; transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s; cursor: pointer; position: relative; overflow: hidden; }
.tool-card::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 4px; background: linear-gradient(90deg, #4285f4, #34a853, #fbbc04, #ea4335); opacity: 0; transition: opacity 0.2s; }
.tool-card:hover { transform: translateY(-4px); box-shadow: 0 8px 24px rgba(66,133,244,0.15); border-color: #4285f4; }
.tool-card:hover::before { opacity: 1; }
.tool-icon { font-size: 2.2rem; margin-bottom: 12px; display: block; text-align: center; }
.tool-title { color: #4285f4; font-size: 1.5rem; margin: 0 0 12px 0; font-weight: bold; text-align: center; height:45px;overflow:hidden}
.tool-description { color: #555; font-size: 1rem; line-height: 1.6; margin: 0 0 20px 0; text-align: left; min-height: 72px; }
.tool-link { display: block; background: #4285f4; color: #fff; text-align: center; padding: 12px 24px; border-radius: 6px; text-decoration: none; font-size: 1rem; font-weight: 500; transition: background 0.2s, box-shadow 0.2s; box-shadow: 0 2px 6px rgba(66,133,244,0.2); }
.tool-link:hover { background: #2568d6; box-shadow: 0 4px 12px rgba(66,133,244,0.3); }
/* 响应式 */
@media (max-width: 1200px) { .tools-grid { grid-template-columns: repeat(3, 1fr); gap: 20px; } }
@media (max-width: 900px) { .tools-grid { grid-template-columns: repeat(2, 1fr); gap: 18px; } }
@media (max-width: 680px) {
  .header { padding: 28px 0 24px 0; }
  .header-top { padding: 0 16px; flex-direction: column; align-items: flex-start; gap: 18px; min-height: auto; }
  .header-right { width: 100%; }
  .header-nav { width: 100%; justify-content: flex-start; flex-wrap: wrap; gap: 6px; }
  .nav-link { font-size: 0.88rem; padding: 8px 16px; }
  .logo-icon { width: 36px; height: 36px; }
  .logo-icon svg { width: 20px; height: 20px; }
  .logo-text h1 { font-size: 1.45rem; }
  .logo-text p { font-size: 0.82rem; }
  .header-search { padding: 0 16px; }
  .search-box-wrapper { max-width: 100%; padding: 4px 4px 4px 16px; }
  .search-input { font-size: 14px; padding: 10px 6px; }
  .search-btn { width: 36px; height: 36px; }
  .category-container { padding: 0 16px; gap: 8px; }
  .category-btn { padding: 6px 16px; font-size: 0.9rem; }
  .tools-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .tool-card { padding: 24px 20px; }
  .tool-icon { font-size: 2rem; }
  .tool-title { font-size: 1.3rem; }
  .tool-description { min-height: auto; font-size: 0.95rem; }
}
@media (max-width: 480px) { .tools-grid { grid-template-columns: 1fr; gap: 16px; } }
/* 列表样式 */
ul, ol { padding-left: 1.55em; margin-left: 0; }
ul li, ol li { font-size: 1.05em; line-height: 1.83; position: relative; }
ul li::marker, ol li::marker { color: #44aaff; font-size: 1.2em; font-weight: bold; }
.main .content ul li::marker, .main .content ol li::marker { color: #3598dc; font-size: 1.15em; }