:root {
    --primary-color: #2B5797;
    --danger-color: #E53935;
    --secondary-color: #607D8B;
    --light-bg: #f8f9fa;
    --dark-text: #212121;
}

/* 全局样式 */
body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--dark-text);
    line-height: 1.6;
}

/* 导航栏样式 */
.navbar-brand h5 {
    color: white;
    font-size: 1.2rem;
}

.navbar-nav .nav-link {
    font-weight: 500;
    transition: all 0.3s ease;
}

.navbar-nav .nav-link:hover {
    color: var(--danger-color) !important;
}

/* 服务卡片样式 */
.service-card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.service-icon i {
    font-size: 3rem;
}

/* 城市选择样式 */
.city-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    gap: 10px;
    max-height: 200px;
    overflow-y: auto;
}

.city-item {
    display: block;
    padding: 8px 12px;
    background: var(--light-bg);
    color: var(--primary-color);
    text-decoration: none;
    border-radius: 20px;
    text-align: center;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.city-item:hover {
    background: var(--primary-color);
    color: white;
    transform: scale(1.05);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .city-container {
        grid-template-columns: repeat(auto-fill, minmax(60px, 1fr));
    }
    
    .service-icon i {
        font-size: 2rem;
    }
}
/* ========= 联系我们 ========= */
.accordion-button:not(.collapsed){
    background-color:var(--danger-color);
    color:#fff;
}
.accordion-button:focus{
    box-shadow:none;
}
/* 时间线 */
.timeline::before{
    content:'';
    position:absolute;
    left:50%;
    top:0;
    bottom:0;
    width:2px;
    background:var(--primary-color);
    transform:translateX(-50%);
}
/* 城市网格 */
.city-grid{
    display:grid;
    grid-template-columns:repeat(auto-fill, minmax 70px, 1fr);
    gap:8px;
    max-height:220px;
    overflow-y:auto;
}
.city-grid .city-item{
    background:#f1f3f5;
    color:var(--primary-color);
    border-radius:20px;
    padding:6px 0;
    text-align:center;
    font-size:.8rem;
    text-decoration:none;
    transition:all .3s;
}
.city-grid .city-item:hover{
    background:var(--primary-color);
    color:#fff;
    transform:scale(1.05);
}
/* 返回顶部 */
#backToTop{
    z-index:1050;
}
/* 移动端固定底部 */
@media(max-width:576px){
    .navbar-brand h5{font-size:1rem;}
    .timeline::before{display:none;}
}