/* 全局样式 */
:root {
    --primary: #4361ee;
    --secondary: #3a0ca3;
    --success: #4cc9f0;
    --light: #f8f9fa;
    --dark: #212529;
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Noto Sans SC', sans-serif;
    color: var(--dark);
    line-height: 1.6;
    padding-top: 120px; /* 导航栏高度 */
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 0;
    width: 60px;
    height: 4px;
    background: var(--primary);
    border-radius: 2px;
}

.lead {
    font-size: 1.25rem;
    font-weight: 300;
}

/* 导航栏 */
.navbar {
    transition: var(--transition);
    padding: 1rem 0;
}

.navbar-brand {
    font-size: 1.8rem;
    display: flex;
    align-items: center;
}

.navbar-brand img {
    height: 70px;
    width: auto;
    object-fit: contain;
}

.nav-link {
    font-weight: 500;
    margin: 0 0.5rem;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

/* Hero 区域 */
.hero {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    padding-top: 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    color: var(--dark);
}

.hero p {
    font-size: 1.2rem;
    color: #555;
}

/* 卡片 */
.card {
    transition: var(--transition);
    border-radius: 1rem;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow);
}

.icon-wrapper {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: rgba(67, 97, 238, 0.1);
    margin-bottom: 1.5rem;
}

/* 表单 */
form .form-control {
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    border: 1px solid #ddd;
    transition: var(--transition);
}

form .form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 0.25rem rgba(67, 97, 238, 0.25);
}

/* 页脚 */
footer a {
    text-decoration: none;
    transition: var(--transition);
}

footer a:hover {
    opacity: 0.8;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .navbar-brand img {
        height: 60px;
    }
    
    .navbar-brand {
        font-size: 1.5rem;
    }
    
    body {
        padding-top: 110px;
    }
}

@media (max-width: 576px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .navbar-brand img {
        height: 60px;
    }
    
    .navbar-brand {
        font-size: 1.3rem;
    }
    
    .btn-lg {
        padding: 0.75rem 1.5rem;
        font-size: 1rem;
    }
    
    .card-body {
        padding: 1.5rem;
    }
    
    body {
        padding-top: 100px;
    }
}

/* 工具类 */
.hover-shadow:hover {
    box-shadow: var(--shadow);
}

.bg-light {
    background-color: #f8f9fa !important;
}

.text-primary {
    color: var(--primary) !important;
}

.btn-primary {
    background-color: var(--primary);
    border-color: var(--primary);
}

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

.btn-outline-primary {
    color: var(--primary);
    border-color: var(--primary);
}

.btn-outline-primary:hover {
    background-color: var(--primary);
    border-color: var(--primary);
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}