/* 响应式设计 */

/* 平板电脑 */
@media (max-width: 992px) {
    /* 导航调整 */
    .main-nav li {
        margin: 0 10px;
    }
    
    .logo-image {
        height: auto;
        width: auto;
        max-height: 45px;
        max-width: 180px;
    }
    
    /* 主横幅区域 */
    .hero-banner {
        padding: 0 5px;
    }
    
    .hero-image {
        max-width: 1000px;
    }
    
    /* 课程横幅区域 */
    .course-banner {
        padding: 0 5px;
    }
    
    .course-banner-image {
        max-width: 1000px;
    }
    
    /* 介绍部分平板适配 */
    .intro-section {
        padding: 60px 0;
    }
    
    .intro-content {
        max-width: 700px;
        padding: 0 30px;
    }
    
    .section-title {
        font-size: 2.5rem;
    }
    
    .intro-text {
        font-size: 1.2rem;
    }
    
    /* 特色网格 */
    .features-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    /* 课程页面平板适配 */
    .course-item {
        grid-template-columns: 240px 1fr;
    }
    
    .course-certificate {
        min-height: 180px;
        padding: 15px;
    }
    
    .instructors-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .section-title-en {
        font-size: 2rem;
    }
    
    .section-title-zh {
        font-size: 1.5rem;
    }
    
    /* 关于页面 */
    .about-intro {
        flex-direction: column;
        text-align: center;
    }
    
    .about-image {
        max-width: 500px;
        margin: 0 auto;
    }
    
    /* 页脚 */
    .footer-info {
        flex-direction: column;
        gap: 30px;
        align-items: center;
    }
    
    .footer-qr-section,
    .footer-contact-section {
        align-items: center;
        text-align: center;
    }
    
    .footer-qr-section img {
        width: 90px;
        height: 90px;
    }
    
    .footer-qr-text {
        height: 90px;
    }
    
    .footer-qr-title {
        font-size: 1.3rem;
    }
    
    .footer-contact-title {
        font-size: 1.3rem;
    }
    
    .footer-contact-section {
        height: auto;
    }
    
    .footer-contact-info img {
        width: 30px;
        height: 30px;
    }
    
    .footer-logo,
    .footer-contact {
        text-align: center;
    }
    
    .footer-qr img {
        width: 100px;
        height: 100px;
    }
    
    /* 二维码浮窗平板适配 */
    .qr-modal-content {
        max-width: 80%;
    }
}

/* 手机 */
@media (max-width: 768px) {
    /* 导航栏 */
    header .container {
        height: 60px;
    }
    
    .logo-image {
        height: auto;
        width: auto;
        max-height: 40px;
        max-width: 160px;
    }
    
    nav {
        display: flex;
        align-items: center;
        gap: 10px;
    }
    
    .main-nav {
        display: none;
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        width: 100%;
        background-color: var(--white);
        flex-direction: column;
        padding: 20px 0;
        box-shadow: var(--shadow);
        z-index: 1001;
    }
    
    .main-nav.active {
        display: flex;
    }
    
    .main-nav li {
        margin: 10px 20px;
    }
    
    .mobile-menu-toggle {
        display: block;
        order: 2;
    }
    
    .language-toggle {
        order: 1;
        margin-left: 0;
        margin-right: 10px;
    }
    
    .language-toggle a {
        padding: 6px 16px;
        font-size: 12px;
        border-radius: 18px;
        white-space: nowrap;
        min-width: 50px;
        text-align: center;
    }
    
    /* 主横幅区域 */
    .hero-banner {
        padding: 0 10px;
    }
    
    .hero-image {
        max-width: 100%;
    }
    
    /* 课程横幅区域 */
    .course-banner {
        padding: 0 10px;
    }
    
    .course-banner-image {
        max-width: 100%;
    }
    
    /* 介绍部分手机适配 */
    .intro-section {
        padding: 50px 0;
    }
    
    .intro-content {
        max-width: 100%;
        padding: 0 20px;
    }
    
    .section-title {
        font-size: 2rem;
        margin-bottom: 25px;
    }
    
    .intro-text {
        font-size: 1.1rem;
        margin-bottom: 40px;
    }
    
    /* 按钮 */
    .cta-buttons {
        flex-direction: column;
        align-items: center;
        gap: 15px;
    }
    
    .btn {
        width: 100%;
        max-width: 280px;
        padding: 12px 28px;
        font-size: 15px;
    }
    
    /* 课程页面手机适配 */
    .course-item {
        grid-template-columns: 1fr;
    }
    
    .course-certificate {
        min-height: 150px;
        padding: 20px;
    }
    
    .course-certificate img {
        max-width: 200px;
    }
    
    .course-info {
        padding: 25px;
    }
    
    .course-footprint {
        bottom: 0;
        right: 0;
        width: 140px;
        height: auto;
    }
    
    .instructor-card {
        flex-direction: column;
        text-align: center;
        padding: 25px;
    }
    
    .instructor-photo {
        width: 100px;
        height: 100px;
        margin: 0 auto 20px;
    }
    
    .instructor-info {
        text-align: center;
    }
    
    .section-title-en {
        font-size: 1.8rem;
    }
    
    .section-title-zh {
        font-size: 1.3rem;
    }
    
    .instructors-section {
        padding: 60px 0;
    }
    
    /* 页脚 */
    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
        text-align: center;
    }
    
    .footer-info {
        flex-direction: column;
        gap: 25px;
        align-items: center;
    }
    
    /* 二维码浮窗手机适配 */
    .qr-modal-content {
        max-width: 85%;
    }
    
    .qr-close {
        top: -8px;
        right: -8px;
        font-size: 18px;
        width: 26px;
        height: 26px;
    }
    
    .qr-text {
        font-size: clamp(0.9rem, 5vw, 1.8rem);
    }
}

/* 小型手机 */
@media (max-width: 480px) {
    /* 内边距调整 */
    .features-preview,
    .under-construction {
        padding: 40px 0;
    }
    
    .intro-section {
        padding: 40px 0;
    }
    
    .container {
        padding: 0 15px;
    }
    
    .intro-content {
        padding: 0 15px;
    }
    
    .logo-image {
        height: auto;
        width: auto;
        max-height: 35px;
        max-width: 140px;
    }
    
    /* 主横幅区域 */
    .hero-banner {
        padding: 0 15px;
    }
    
    .hero-image {
        max-width: 100%;
    }
    
    /* 课程横幅区域 */
    .course-banner {
        padding: 0 15px;
    }
    
    /* 介绍文字 */
    .section-title {
        font-size: 1.8rem;
    }
    
    .intro-text {
        font-size: 1rem;
        line-height: 1.7;
    }
    
    /* 课程页面小屏手机适配 */
    .course-certificate {
        padding: 15px;
    }
    
    .course-certificate img {
        max-width: 180px;
    }
    
    .course-info {
        padding: 20px;
    }
    
    .course-footprint {
        bottom: 0;
        right: 0;
        width: 120px;
        height: auto;
    }
    
    .instructor-card {
        padding: 20px;
    }
    
    .instructor-photo {
        width: 80px;
        height: 80px;
    }
    
    .section-title-en {
        font-size: 1.5rem;
    }
    
    .section-title-zh {
        font-size: 1.2rem;
    }
    
    /* 二维码浮窗小屏手机适配 */
    .qr-modal-content {
        max-width: 90%;
    }
    
    .qr-text {
        font-size: clamp(0.8rem, 6vw, 1.6rem);
    }
}