*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
a{
    text-decoration: none;
}
.flex {
    display: flex;
}
.flex-center {
    justify-content: center;
    align-items: center;
}
.flex-between {
    justify-content: space-between;
    align-items: center;
}
.wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header Styles */
.header {
    width: 100%;
    height: 80px;
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100;
}

.header .wrapper {
    height: 100%;
}

.header .logo {
    height: 40px;
}

.nav {
    display: flex;
    gap: 40px;
}

.nav a {
    color: #092e53;
    font-size: 16px;
    transition: all 0.3s;
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 4px;
}

.nav a:hover {
    color: #2e93fe;
    background: rgba(46, 147, 254, 0.1);
}

.nav-video {
    background: #2e93fe;
    color: #fff !important;
}

.nav-video:hover {
    background: #1a7ae8 !important;
    color: #fff !important;
}

/* 移动端导航样式 */
.mobile-menu-btn {
    display: none;
    width: 30px;
    height: 24px;
    position: relative;
    cursor: pointer;
    z-index: 1000;
}

.mobile-menu-btn span {
    display: block;
    position: absolute;
    height: 2px;
    width: 100%;
    background: #092e53;
    border-radius: 2px;
    transition: all 0.3s;
}

.mobile-menu-btn span:nth-child(1) { top: 0; }
.mobile-menu-btn span:nth-child(2) { top: 50%; transform: translateY(-50%); }
.mobile-menu-btn span:nth-child(3) { bottom: 0; }

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg);
    top: 50%;
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg);
    bottom: 40%;
}

/* Video Content Styles */
.video-content {
    margin-top: 120px;
    padding: 40px 0;
}

.video-title {
    font-size: 36px;
    color: #092e53;
    text-align: center;
    margin-bottom: 40px;
}

.video-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 40px;
    padding: 20px 0;
    max-width: 1200px;
    margin: 0 auto;
}

.video-item {
    background: #fff;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    transition: all 0.3s;
    width: 100%;
    gap: 30px;
    padding: 20px;
    align-items: flex-start;
}

.video-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.12);
}

.video-thumbnail {
    width: 300px;
    flex-shrink: 0;
    background: #f5f5f5;
    position: relative;
    overflow: hidden;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin: 20px auto 0;
}

.video-thumbnail video {
    width: 100%;
    height: auto;
    display: block;
    aspect-ratio: 9/20;
    background: #000;

}

.play-icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(46, 147, 254, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s;
}

.video-item:hover .play-icon {
    background: #2e93fe;
    transform: translate(-50%, -50%) scale(1.1);
}

.play-icon::after {
    content: '';
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 10px 0 10px 16px;
    border-color: transparent transparent transparent #ffffff;
    margin-left: 4px;
}

.video-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 300px;
}

.video-info h3 {
    font-size: 20px;
    color: #092e53;
    margin-bottom: 15px;
}

.video-info .desc-list {
    margin-bottom: 20px;
    list-style: none;
    padding: 0;
}

.video-info .desc-list li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 10px;
    color: #666;
    font-size: 14px;
    line-height: 1.6;
}

.video-info .desc-list li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: #2e93fe;
    font-size: 16px;
}

.video-info .app-links {
    margin-top: auto;
    padding-top: 15px;
    border-top: 1px solid #eee;
}

.video-info .app-links a {
    display: inline-block;
    padding: 8px 16px;
    background: #eaf5ff;
    color: #2e93fe;
    border-radius: 4px;
    margin-right: 10px;
    font-size: 14px;
    transition: all 0.3s;
}

.video-info .app-links a:hover {
    background: #2e93fe;
    color: #fff;
}

/* Footer Styles */
.footer {
    background: #092e53;
    color: #fff;
    padding: 40px 0 0;
    margin-top: 60px;
}

.footer .wrapper {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
}

.footer-section {
    flex: 1;
    padding: 0 20px;
}

.footer-title {
    font-size: 18px;
    margin-bottom: 20px;
    color: #fff;
}

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

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

.footer-links a {
    color: rgba(255,255,255,0.8);
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #2e93fe;
}

.contact-info {
    color: rgba(255,255,255,0.8);
    line-height: 1.8;
}

.copyright {
    text-align: center;
    padding: 20px 0;
    background: #051a2f;
    color: rgba(255,255,255,0.6);
}

@media (max-width: 1024px) {
    .video-item {
        flex-direction: column;
        padding: 15px;
        align-items: center;
    }

    .video-thumbnail {
        width: 280px;
        margin: 0 auto;
    }

    .video-info {
        min-width: auto;
        width: 100%;
    }
}

@media (max-width: 768px) {
    .header {
        padding: 0 20px;
    }

    .mobile-menu-btn {
        display: block;
    }

    .nav {
        position: fixed;
        top: 80px;
        left: 0;
        width: 100%;
        background: #fff;
        padding: 20px;
        flex-direction: column;
        align-items: center;
        gap: 20px;
        box-shadow: 0 4px 10px rgba(0,0,0,0.1);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s;
    }

    .nav.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav a {
        width: 100%;
        text-align: center;
        padding: 12px;
    }

    .video-list {
        grid-template-columns: 1fr;
        padding: 20px;
    }

    .footer .wrapper {
        flex-direction: column;
    }

    .footer-section {
        margin-bottom: 30px;
    }

    .video-thumbnail {
        width: 240px;
    }

    .video-info {
        padding: 15px 0;
    }
}

@media (min-width: 769px) and (max-width: 1200px) {
    .video-list {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1201px) {
    .video-list {
        grid-template-columns: repeat(3, 1fr);
    }
}

.video-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.video-section {
    flex: 1;
    background: #fff;
    border-radius: 16px;
    padding: 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.video-section h2 {
    font-size: 24px;
    color: #092e53;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid #eef6fd;
}

.video-section p {
    color: #666;
    line-height: 1.8;
    margin-bottom: 20px;
}

.video-wrapper {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    background: #000;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.video-wrapper video {
    width: 100%;
    height: auto;
    display: block;
}

@media (max-width: 1200px) {
    .video-container {
        padding: 20px;
    }
}

@media (max-width: 768px) {
    .video-section {
        padding: 20px;
    }

    .video-section h2 {
        font-size: 20px;
    }
}