/* 全局样式 */
:root {
    --primary: #1e88e5;
    --primary-dark: #1565c0;
    --secondary: #ff6d00;
    --light: #f5f7fa;
    --dark: #263238;
    --gray: #78909c;
    --success: #43a047;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f9f9f9;
    color: #333;
    line-height: 1.6;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

section {
    padding: 60px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
    position: relative;
}

    .section-title h2 {
        font-size: 2.2rem;
        color: var(--dark);
        margin-bottom: 15px;
    }

    .section-title p {
        color: var(--gray);
        max-width: 700px;
        margin: 0 auto;
        font-size: 1.1rem;
    }

    .section-title::after {
        content: '';
        position: absolute;
        bottom: -15px;
        left: 50%;
        transform: translateX(-50%);
        width: 70px;
        height: 4px;
        background: var(--primary);
        border-radius: 2px;
    }

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--primary);
    color: white;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

    .btn:hover {
        background: var(--primary-dark);
        transform: translateY(-3px);
        box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    }

.btn-secondary {
    background: var(--secondary);
}

    .btn-secondary:hover {
        background: #e65100;
    }

/* 导航栏 */
header {
    background-color: white;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    display: flex;
    align-items: center;
}

    .logo img {
        height: 40px;
        margin-right: 10px;
    }

    .logo h1 {
        font-size: 1.5rem;
        color: var(--primary);
        font-weight: 700;
    }

.nav-links {
    display: flex;
    list-style: none;
}

    .nav-links li {
        margin-left: 30px;
    }

    .nav-links a {
        text-decoration: none;
        color: var(--dark);
        font-weight: 500;
        font-size: 1.05rem;
        transition: color 0.3s;
        position: relative;
    }

        .nav-links a:hover {
            color: var(--primary);
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -5px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--primary);
            transition: width 0.3s;
        }

        .nav-links a:hover::after {
            width: 100%;
        }

/* 英雄区域 */
.hero {
    background: linear-gradient(135deg, rgba(30,136,229,0.9) 0%, rgba(33,150,243,0.9) 100%), url('https://images.unsplash.com/photo-1542831371-29b0f74f9713?ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=1200&q=80');
    background-size: cover;
    background-position: center;
    color: white;
    padding: 100px 0;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 800;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-top: 30px;
}

/* 功能区域 */
.features {
    background-color: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.feature-card {
    background: white;
    border-radius: 10px;
    padding: 30px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s ease;
}

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

.feature-icon {
    width: 80px;
    height: 80px;
    background: rgba(30,136,229,0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    color: var(--primary);
    font-size: 2rem;
}

.feature-card h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: var(--dark);
}

/* 课程区域 */
.courses {
    background-color: var(--light);
}

.course-categories {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 40px;
}

.category-btn {
    padding: 10px 25px;
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 30px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

    .category-btn.active, .category-btn:hover {
        background: var(--primary);
        color: white;
        border-color: var(--primary);
    }

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
}

.course-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s;
}

    .course-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    }

.course-image {
    height: 200px;
    background-color: #e0e0e0;
    position: relative;
    overflow: hidden;
}

    .course-image img {
        width: 100%;
        height: 100%;
        object-fit: cover;
        transition: transform 0.5s;
    }

.course-card:hover .course-image img {
    transform: scale(1.05);
}

.course-level {
    position: absolute;
    top: 15px;
    right: 15px;
    background: var(--secondary);
    color: white;
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.course-content {
    padding: 25px;
}

    .course-content h3 {
        font-size: 1.3rem;
        margin-bottom: 15px;
        color: var(--dark);
    }

.course-meta {
    display: flex;
    justify-content: space-between;
    margin-top: 20px;
    color: var(--gray);
    font-size: 0.9rem;
}



/* 注册区域 */
.cta {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-align: center;
    padding: 80px 0;
}

    .cta h2 {
        font-size: 2.5rem;
        margin-bottom: 20px;
    }

    .cta p {
        max-width: 700px;
        margin: 0 auto 30px;
        font-size: 1.1rem;
        opacity: 0.9;
    }

/* 页脚 */
footer {
    background: var(--dark);
    color: white;
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h3 {
    font-size: 1.3rem;
    margin-bottom: 25px;
    position: relative;
    padding-bottom: 10px;
}

    .footer-col h3::after {
        content: '';
        position: absolute;
        bottom: 0;
        left: 0;
        width: 50px;
        height: 2px;
        background: var(--primary);
    }

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

    .footer-links li {
        margin-bottom: 15px;
    }

    .footer-links a {
        color: #b0bec5;
        text-decoration: none;
        transition: color 0.3s;
    }

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

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

    .social-links a {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 40px;
        height: 40px;
        background: rgba(255,255,255,0.1);
        border-radius: 50%;
        color: white;
        transition: all 0.3s;
    }

        .social-links a:hover {
            background: var(--primary);
            transform: translateY(-3px);
        }

.copyright {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: #b0bec5;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.3rem;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .nav-links {
        display: none;
    }

    .section-title h2 {
        font-size: 1.8rem;
    }
}


/* 每日计划 */
.daily-plan {
    background: var(--light);
    padding: 50px 0;
}

.plan-container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--card-shadow);
}

.plan-header {
    background: var(--primary);
    color: white;
    padding: 25px;
    text-align: center;
}

    .plan-header h3 {
        font-size: 1.8rem;
        margin-bottom: 10px;
    }

.plan-body {
    padding: 30px;
}

.plan-grid {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 20px;
}

.time-slot {
    font-weight: 600;
    color: var(--primary);
    display: flex;
    align-items: center;
}

    .time-slot::before {
        content: '';
        display: inline-block;
        width: 12px;
        height: 12px;
        background: var(--primary);
        border-radius: 50%;
        margin-right: 10px;
    }

.activity {
    background: rgba(30, 136, 229, 0.05);
    padding: 15px;
    border-radius: 8px;
    border-left: 3px solid var(--primary);
}



.container2 {
    width: 100%;
    max-width: 1800px;
    margin: 0 auto;
    padding: 0 20px;
}
.timeline-container {
    background: white;
    border-radius: 20px;
    box-shadow: var(--card-shadow);
    padding: 40px;
    margin: 0 auto 60px;
    max-width: 1800px;
    position: relative;
}

.timeline-header {
    text-align: center;
    margin-bottom: 50px;
}

    .timeline-header h2 {
        font-size: 2.5rem;
        color: var(--dark);
        margin-bottom: 15px;
    }

    .timeline-header p {
        color: var(--gray);
        font-size: 1.1rem;
        max-width: 700px;
        margin: 0 auto;
    }

    .timeline-header::after {
        content: '';
        display: block;
        width: 100px;
        height: 4px;
        background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
        border-radius: 2px;
        margin: 20px auto 0;
    }

.timeline-horizontal {
    display: flex;
    justify-content: space-between;
    position: relative;
}

.timeline-line {
    position: absolute;
    top: 100px;
    left: 5%;
    width: 90%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
    z-index: 1;
    border-radius: 2px;
}
.phase {
    width: 23%;
    background: white;
    border-radius: 15px;
    box-shadow: var(--card-shadow);
    padding: 30px;
    position: relative;
    z-index: 2;
    transition: var(--transition);
    border-top: 4px solid var(--primary);
}

    .phase:hover {
        transform: translateY(-10px);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.12);
    }

    .phase:nth-child(2) {
        border-top-color: #43a047;
    }

    .phase:nth-child(3) {
        border-top-color: #ff6d00;
    }

    .phase:nth-child(4) {
        border-top-color: #ab47bc;
    }

.phase-number {
    width: 50px;
    height: 50px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin: -40px auto 25px;
    position: relative;
    box-shadow: 0 5px 15px rgba(30, 136, 229, 0.4);
}

.phase:nth-child(2) .phase-number {
    background: #43a047;
    box-shadow: 0 5px 15px rgba(67, 160, 71, 0.4);
}

.phase:nth-child(3) .phase-number {
    background: #ff6d00;
    box-shadow: 0 5px 15px rgba(255, 109, 0, 0.4);
}

.phase:nth-child(4) .phase-number {
    background: #ab47bc;
    box-shadow: 0 5px 15px rgba(171, 71, 188, 0.4);
}

.phase-title {
    font-size: 1.4rem;
    color: var(--dark);
    margin-bottom: 20px;
    text-align: center;
    font-weight: 700;
}

.phase-duration {
    background: rgba(30, 136, 229, 0.1);
    color: var(--primary);
    padding: 6px 15px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    display: inline-block;
    margin-bottom: 20px;
}

.phase:nth-child(2) .phase-duration {
    background: rgba(67, 160, 71, 0.1);
    color: #43a047;
}

.phase:nth-child(3) .phase-duration {
    background: rgba(255, 109, 0, 0.1);
    color: #ff6d00;
}

.phase:nth-child(4) .phase-duration {
    background: rgba(171, 71, 188, 0.1);
    color: #ab47bc;
}

.phase-section {
    margin-bottom: 25px;
}

    .phase-section h4 {
        color: var(--primary);
        margin-bottom: 12px;
        font-size: 1.1rem;
        display: flex;
        align-items: center;
        gap: 8px;
    }

        .phase-section h4 i {
            font-size: 1.2rem;
        }

    .phase-section ul {
        list-style-type: none;
        padding-left: 5px;
    }

    .phase-section li {
        margin-bottom: 10px;
        padding-left: 25px;
        position: relative;
        font-size: 0.95rem;
    }

        .phase-section li::before {
            content: '•';
            position: absolute;
            left: 10px;
            color: var(--primary);
            font-weight: bold;
        }
.resources-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    margin-top: 10px;
}

.resource-card {
    background: var(--light);
    border-radius: 10px;
    padding: 15px;
    transition: var(--transition);
    border-left: 3px solid var(--primary);
}

    .resource-card:hover {
        background: rgba(30, 136, 229, 0.1);
        transform: translateX(5px);
    }

    .resource-card h5 {
        color: var(--dark);
        margin-bottom: 5px;
        font-size: 1rem;
    }

    .resource-card p {
        font-size: 0.85rem;
        color: var(--gray);
        line-height: 1.5;
    }
/* 下拉菜单 */
.dropdown {
    position: relative;
}

.dropdown-content {
    display: none;
    position: absolute;
    background: white;
    min-width: 200px;
    box-shadow: 0 8px 16px rgba(0,0,0,0.1);
    border-radius: 8px;
    z-index: 1;
    top: 100%;
    left: 0;
    padding: 10px 0;
}

.dropdown:hover .dropdown-content {
    display: block;
}

.dropdown-content a {
    display: block;
    padding: 10px 20px;
    color: var(--dark);
    text-decoration: none;
    transition: all 0.2s;
}

    .dropdown-content a:hover {
        background: rgba(74, 110, 224, 0.05);
        color: var(--primary);
    }