/* 全局变量 - 学术稳重风格 */
:root {
    --primary-color: #1a5f7a; /* 深蓝绿 */
    --secondary-color: #159895; /* 青绿 */
    --accent-color: #ffc857; /* 活力黄 */
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-main: #2c3e50;
    --text-light: #576574;
    --border-radius: 6px;
    --shadow: 0 4px 12px rgba(26, 95, 122, 0.1);
    --font-family: 'Georgia', 'Times New Roman', 'PingFang SC', serif; /* 衬线体增加学术感 */
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

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

/* 顶部导航 */
.ad-header {
    background: var(--surface-color);
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 4px solid var(--primary-color);
}

.header-flex {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
}

.nav-links a {
    margin: 0 20px;
    font-weight: 600;
    color: var(--text-main);
    font-size: 1rem;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--secondary-color);
}

.btn-apply {
    background: var(--primary-color);
    color: var(--white);
    padding: 10px 25px;
    border-radius: var(--border-radius);
    font-weight: bold;
    box-shadow: 0 4px 10px rgba(26, 95, 122, 0.3);
}

.btn-apply:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

/* 英雄区域 */
.hero-banner {
    padding: 100px 0;
    background: linear-gradient(to right, #eef2f3, #8e9eab);
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 60px;
}

.hero-text {
    flex: 1;
}

.tag-year {
    display: inline-block;
    background: var(--accent-color);
    color: var(--text-main);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.9rem;
    margin-bottom: 20px;
    font-weight: bold;
}

.hero-text h1 {
    font-size: 3.5rem;
    color: var(--primary-color);
    margin-bottom: 15px;
    line-height: 1.1;
}

.subtitle {
    font-size: 1.3rem;
    color: var(--text-light);
    margin-bottom: 30px;
    font-style: italic;
}

.stats-row {
    display: flex;
    gap: 40px;
    margin-bottom: 40px;
    border-top: 1px solid #ddd;
    border-bottom: 1px solid #ddd;
    padding: 20px 0;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-item strong {
    font-size: 1.8rem;
    color: var(--secondary-color);
}

.stat-item span {
    font-size: 0.9rem;
    color: var(--text-light);
}

.hero-btns {
    display: flex;
    gap: 20px;
}

.btn-primary {
    padding: 15px 35px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: var(--border-radius);
    font-weight: bold;
    font-size: 1.1rem;
}

.btn-primary:hover {
    background: var(--secondary-color);
    transform: translateY(-2px);
}

.btn-secondary {
    padding: 15px 35px;
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    border-radius: var(--border-radius);
    font-weight: bold;
    font-size: 1.1rem;
}

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

.hero-img-box {
    flex: 1;
}

.hero-img-box img {
    width: 100%;
    border-radius: var(--border-radius);
    box-shadow: 0 15px 30px rgba(0,0,0,0.15);
    border: 8px solid var(--white);
}

/* 通用区块 */
.section-area {
    padding: 80px 0;
}

.bg-white {
    background: #ffffff;
}

.bg-gray {
    background: #f1f2f6;
}

.bg-blue {
    background: var(--primary-color);
    color: var(--white);
}

.section-head {
    text-align: center;
    margin-bottom: 60px;
}

.section-head h2 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.section-head.light h2 {
    color: var(--white);
}

.section-head p {
    color: var(--text-light);
    font-size: 1.1rem;
}

.section-head.light p {
    color: #e0e0e0;
}

/* 专业卡片 */
.major-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 30px;
}

.major-card {
    background: var(--surface-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s;
    border: 1px solid #eee;
}

.major-card:hover {
    transform: translateY(-10px);
}

.card-img img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.card-body {
    padding: 25px;
}

.card-body h3 {
    font-size: 1.4rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.card-body p {
    color: var(--text-light);
    margin-bottom: 20px;
    font-size: 0.95rem;
}

.tags {
    display: flex;
    gap: 10px;
}

.tags li {
    background: #eef2f3;
    color: var(--primary-color);
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: bold;
}

/* 校园Flex布局 */
.campus-flex {
    display: flex;
    gap: 50px;
    align-items: center;
}

.campus-info {
    flex: 1;
}

.info-item {
    margin-bottom: 30px;
    padding-left: 20px;
    border-left: 4px solid var(--secondary-color);
}

.info-item h3 {
    font-size: 1.3rem;
    margin-bottom: 8px;
    color: var(--primary-color);
}

.info-item p {
    color: var(--text-light);
}

.campus-gallery {
    flex: 1;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
}

.campus-gallery img:first-child {
    grid-column: span 2;
    height: 200px;
    object-fit: cover;
    border-radius: var(--border-radius);
}

.campus-gallery img:not(:first-child) {
    height: 150px;
    object-fit: cover;
    border-radius: var(--border-radius);
}

/* 报名流程 */
.process-steps {
    display: flex;
    justify-content: space-between;
    margin-bottom: 50px;
    position: relative;
}

.process-steps::before {
    content: '';
    position: absolute;
    top: 25px;
    left: 50px;
    right: 50px;
    height: 2px;
    background: rgba(255,255,255,0.3);
    z-index: 0;
}

.step {
    position: relative;
    z-index: 1;
    text-align: center;
    flex: 1;
    padding: 0 10px;
}

.step-num {
    width: 50px;
    height: 50px;
    background: var(--accent-color);
    color: var(--text-main);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
    margin: 0 auto 20px;
    border: 4px solid var(--primary-color);
}

.step h4 {
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.step p {
    font-size: 0.9rem;
    opacity: 0.8;
}

.cta-center {
    text-align: center;
}

.btn-large {
    display: inline-block;
    padding: 15px 50px;
    background: var(--accent-color);
    color: var(--text-main);
    border-radius: 30px;
    font-weight: bold;
    font-size: 1.2rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.btn-large:hover {
    background: #ffdb85;
    transform: scale(1.05);
}

/* 页脚 */
.site-footer {
    background: #154360;
    color: #d6eaf8;
    padding: 60px 0 20px;
}

.footer-layout {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h4 {
    color: var(--white);
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-col ul li {
    margin-bottom: 10px;
}

.footer-col ul li a:hover {
    color: var(--accent-color);
}

.copyright {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #1a5f7a;
    font-size: 0.85rem;
}

/* 响应式适配 */
@media (max-width: 768px) {
    .header-flex {
        flex-direction: column;
        height: auto;
        padding: 15px 0;
        gap: 15px;
    }

    .nav-links {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
        gap: 10px;
    }

    .hero-content {
        flex-direction: column-reverse;
        text-align: center;
    }

    .stats-row {
        justify-content: center;
    }

    .hero-btns {
        justify-content: center;
    }

    .campus-flex {
        flex-direction: column;
    }

    .process-steps {
        flex-direction: column;
        gap: 30px;
    }

    .process-steps::before {
        display: none;
    }

    .footer-layout {
        grid-template-columns: 1fr;
        text-align: center;
    }
}