/* 全局样式 */
:root {
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --dark-color: #343a40;
    --light-color: #f8f9fa;
    --white-color: #ffffff;
    --text-color: #333333;
    --border-color: #dee2e6;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

/* 导航栏 */
.header {
    background-color: var(--white-color);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-menu a {
    color: var(--text-color);
    font-weight: 500;
    transition: var(--transition);
}

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

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--dark-color);
    transition: var(--transition);
}

/* 主内容区 */
.main-content {
    min-height: calc(100vh - 200px);
}

/* 首页Hero区域 */
.hero-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, #0056b3 100%);
    color: var(--white-color);
    padding: 100px 0;
    text-align: center;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.cta-button {
    background-color: var(--white-color);
    color: var(--primary-color);
    padding: 12px 30px;
    border-radius: 50px;
    font-size: 1rem;
    font-weight: 600;
    transition: var(--transition);
}

.cta-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

/* 通用section样式 */
section {
    padding: 80px 0;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--dark-color);
}

/* 关于部分 */
.about-section {
    background-color: var(--light-color);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.8;
}

.about-image img {
    border-radius: 10px;
    box-shadow: var(--shadow);
}

/* 项目部分 */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background-color: var(--white-color);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.project-image {
    height: 200px;
    overflow: hidden;
    background-color: var(--light-color);
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.project-card:hover .project-image img {
    transform: scale(1.1);
}

.project-info {
    padding: 1.5rem;
}

.project-info h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}

.project-info p {
    color: var(--secondary-color);
}

/* 联系部分 */
.contact-section {
    background-color: var(--light-color);
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark-color);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--white-color);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.1);
}

.submit-button {
    background-color: var(--primary-color);
    color: var(--white-color);
    padding: 12px 40px;
    border-radius: 5px;
    font-size: 1rem;
    font-weight: 600;
    transition: var(--transition);
    width: 100%;
}

.submit-button:hover {
    background-color: #0056b3;
}

/* 页脚 */
.footer {
    background-color: var(--dark-color);
    color: var(--white-color);
    padding: 2rem 0;
    text-align: center;
}

.footer .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.social-links {
    display: flex;
    gap: 1.5rem;
}

.social-links a {
    color: var(--white-color);
    transition: var(--transition);
}

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

/* 消息提示框 */
.message-box {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 15px 25px;
    border-radius: 5px;
    color: var(--white-color);
    font-weight: 500;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 9999;
    display: none;
    animation: slideIn 0.3s ease;
}

.message-box.success {
    background-color: #28a745;
}

.message-box.error {
    background-color: #dc3545;
}

.message-box.info {
    background-color: var(--primary-color);
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* 滚动动画 */
.fade-out {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in {
    opacity: 1;
    transform: translateY(0);
}

/* 导航栏滚动效果 */
.header.scrolled {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

/* 平板设备 */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .footer .container {
        flex-direction: column;
        text-align: center;
    }

    .message-box {
        right: 10px;
        left: 10px;
        top: 10px;
    }
}