:root {
    --primary-color: #007bff;
    --primary-hover: #0056b3;
    --primary-highlight: #0069d9;
    --text-color-light: #333;
    --bg-color-light: #ffffff;
    --card-bg-light: #f8f9fa;
    --border-color-light: #e0e0e0;
    --text-color-dark: #f0f0f0;
    --bg-color-dark: #121212;
    --card-bg-dark: #1e1e1e;
    --border-color-dark: #333;
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif
}

html {
    scroll-behavior: smooth
}

body {
    font-family: var(--font-family);
    margin: 0;
    padding: 0;
    background-color: var(--bg-color-light);
    color: var(--text-color-light);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
    padding-top: 70px
}

[data-theme="dark"] body {
    background-color: var(--bg-color-dark);
    color: var(--text-color-dark)
}

.container {
    max-width: 1140px;
    margin: 0 auto;
    padding: 0 20px
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 0.75rem
}

h1 {
    font-size: 3rem
}

h2 {
    font-size: 2.25rem
}

h3 {
    font-size: 1.5rem
}

p {
    margin-bottom: 1rem
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color 0.2s ease
}

@media (hover:hover) {
    a:hover {
        color: var(--primary-hover)
    }
}

img {
    max-width: 100%;
    height: auto
}

.section {
    padding: 70px 0
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 50px;
    color: var(--primary-color)
}

[data-theme="dark"] .section-title {
    color: #4dabf7
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    text-align: center;
    border: 2px solid transparent;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease
}

.btn i {
    margin-right: 8px
}

.btn-large {
    padding: 15px 30px;
    font-size: 1.15rem
}

.btn-primary {
    background-color: var(--primary-color);
    color: #ffffff;
    border-color: var(--primary-color)
}

@media (hover:hover) {
    .btn-primary:hover {
        background-color: var(--primary-hover);
        border-color: var(--primary-hover);
        color: #ffffff;
        transform: translateY(-2px);
        box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15)
    }
}

.btn-primary:active {
    background-color: #004494;
    border-color: #004494;
    color: #ffffff;
    transform: translateY(0);
    box-shadow: none
}

.btn-secondary {
    background-color: transparent;
    color: #ffffff;
    border-color: #ffffff
}

@media (hover:hover) {
    .btn-secondary:hover {
        background-color: rgba(255, 255, 255, 0.1);
        color: #ffffff;
        transform: translateY(-2px);
        box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1)
    }
}

.btn-secondary:active {
    background-color: rgba(255, 255, 255, 0.2);
    transform: translateY(0);
    box-shadow: none
}

.btn-back {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--card-bg-light);
    color: var(--text-color-light);
    border: 1px solid var(--border-color-light);
    cursor: pointer;
    transition: all 0.2s ease
}

[data-theme="dark"] .btn-back {
    background-color: var(--card-bg-dark);
    color: var(--text-color-dark);
    border-color: var(--border-color-dark)
}

@media (hover:hover) {
    .btn-back:hover {
        background-color: var(--primary-color);
        color: white;
        border-color: var(--primary-color);
        transform: translateY(-2px)
    }
}

.btn-back:active {
    background-color: var(--primary-hover);
    color: white;
    border-color: var(--primary-hover);
    transform: translateY(0)
}

.header {
    background-color: var(--bg-color-light);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    padding: 10px 0;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transition: background-color 0.3s, box-shadow 0.3s
}

[data-theme="dark"] .header {
    background-color: var(--card-bg-dark);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2)
}

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

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--text-color-light)
}

[data-theme="dark"] .logo {
    color: var(--text-color-dark)
}

.logo img {
    height: 50px;
    margin-right: 10px
}

.logo .title {
    font-size: 1.3rem;
    font-weight: 600
}

.theme-toggle-btn {
    background: none;
    border: 1px solid var(--border-color-light);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-size: 1.2rem;
    cursor: pointer;
    color: var(--text-color-light);
    transition: all 0.2s ease
}

[data-theme="dark"] .theme-toggle-btn {
    color: var(--text-color-dark);
    border-color: var(--border-color-dark)
}

@media (hover:hover) {
    .theme-toggle-btn:hover {
        background-color: var(--card-bg-light)
    }

    [data-theme="dark"] .theme-toggle-btn:hover {
        background-color: var(--border-color-dark)
    }
}

.theme-toggle-btn:active {
    transform: scale(0.95)
}

#hero {
    background-color: #2c3e50;
    background-image: url('https://gkmh.guokevr.cn/images/Landscape_S03.jpg');
    background-size: cover;
    background-position: center;
    color: #ffffff;
    text-align: center;
    padding: 120px 0;
    position: relative
}

.hero-bg-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
    z-index: 1
}

.hero-content {
    position: relative;
    z-index: 2
}

.hero-title {
    font-size: 3.5rem;
    margin-bottom: 20px;
    font-weight: 700
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 40px;
    font-weight: 300;
    opacity: 0.9
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 40px
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px
}

.feature-card {
    background-color: var(--card-bg-light);
    border: 1px solid var(--border-color-light);
    border-radius: 10px;
    padding: 30px;
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03)
}

[data-theme="dark"] .feature-card {
    background-color: var(--card-bg-dark);
    border-color: var(--border-color-dark);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1)
}

@media (hover:hover) {
    .feature-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 8px 25px rgba(0, 0, 0, 0.07)
    }

    [data-theme="dark"] .feature-card:hover {
        border-color: var(--primary-color);
        box-shadow: 0 8px 25px rgba(0, 123, 255, 0.1)
    }
}

.feature-card i {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 2.5rem
}

.feature-card h3 {
    margin-bottom: 10px;
    font-size: 1.25rem
}

.feature-card p {
    font-size: 0.95rem;
    color: #666;
    margin-bottom: 0
}

[data-theme="dark"] .feature-card p {
    color: #aaa
}

#preview {
    background-color: var(--card-bg-light)
}

[data-theme="dark"] #preview {
    background-color: #000
}

.swiper {
    width: 100%;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1)
}

.swiper-slide {
    position: relative;
    background: #000;
    padding-bottom: 56.25%;
    overflow: hidden
}

.swiper-slide img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.9
}

.slide-caption {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background-color: rgba(0, 0, 0, 0.6);
    color: #ffffff;
    padding: 5px 15px;
    border-radius: 5px;
    font-size: 0.9rem;
    backdrop-filter: blur(5px)
}

.swiper-button-prev,
.swiper-button-next {
    color: #ffffff;
    text-shadow: 0 0 8px rgba(0, 0, 0, 0.6)
}

.swiper-pagination-bullet-active {
    background: var(--primary-color)
}

.showcase-header {
    padding: 20px 0;
    display: flex;
    align-items: center;
    gap: 15px
}

.category-nav {
    position: sticky;
    top: 70px;
    z-index: 90;
    background-color: var(--bg-color-light);
    padding: 15px 0;
    box-shadow: 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
    transition: background-color 0.3s
}

[data-theme="dark"] .category-nav {
    background-color: var(--bg-color-dark);
    box-shadow: 0 4px 6px -4px rgba(0, 0, 0, 0.5)
}

.tabs-wrapper {
    display: flex;
    gap: 12px;
    overflow-x: auto;
    padding-bottom: 5px;
    scrollbar-width: none;
    -ms-overflow-style: none
}

.tabs-wrapper::-webkit-scrollbar {
    display: none
}

.tab-btn {
    padding: 8px 20px;
    border-radius: 20px;
    border: 1px solid var(--border-color-light);
    background-color: var(--card-bg-light);
    color: var(--text-color-light);
    font-size: 0.95rem;
    cursor: pointer;
    white-space: nowrap;
    transition: all 0.2s ease
}

[data-theme="dark"] .tab-btn {
    background-color: var(--card-bg-dark);
    color: var(--text-color-dark);
    border-color: var(--border-color-dark)
}

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

@media (hover:hover) {
    .tab-btn:not(.active):hover {
        border-color: var(--primary-color);
        color: var(--primary-color)
    }
}

.tab-btn:active {
    transform: scale(0.96);
    background-color: var(--primary-hover);
    color: white;
    border-color: var(--primary-hover)
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 15px;
    padding-bottom: 50px
}

.video-card {
    position: relative;
    aspect-ratio: 9 / 16;
    background-color: #000;
    border-radius: 8px;
    overflow: hidden;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease
}

@media (hover:hover) {
    .video-card:hover {
        transform: scale(1.02);
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
        z-index: 5
    }

    .video-card:hover .play-overlay {
        background-color: rgba(0, 0, 0, 0.1)
    }

    .video-card:hover .play-overlay i {
        transform: scale(1.1);
        opacity: 1
    }
}

.video-card:active {
    transform: scale(0.98)
}

.video-poster {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block
}

.play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.2);
    transition: background-color 0.3s ease
}

.play-overlay i {
    color: white;
    font-size: 2.5rem;
    text-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
    opacity: 0.8;
    transition: transform 0.3s ease, opacity 0.3s ease
}

.video-info {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 10px;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
    color: white;
    font-size: 0.85rem;
    pointer-events: none
}

.page-view {
    display: none;
    animation: fadeIn 0.4s ease-in-out
}

.page-view.active {
    display: block
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px)
    }

    to {
        opacity: 1;
        transform: translateY(0)
    }
}

.video-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s;
    backdrop-filter: blur(5px)
}

.video-modal.active {
    display: flex
}

.modal-content {
    position: relative;
    width: 100%;
    height: 100%;
    max-width: 500px;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    margin: auto
}

.video-wrapper {
    width: 100%;
    height: 100%;
    background: #000;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
    position: relative
}

.video-wrapper video {
    width: 100%;
    height: 100%;
    object-fit: contain
}

.close-btn {
    position: absolute;
    top: -40px;
    right: 0;
    background: none;
    border: none;
    color: white;
    font-size: 2rem;
    cursor: pointer;
    z-index: 2001;
    transition: color 0.2s
}

@media (hover:hover) {
    .close-btn:hover {
        color: var(--primary-color)
    }
}

.close-btn:active {
    transform: scale(0.9)
}

.modal-video-title {
    color: #fff;
    text-align: center;
    margin-top: 15px;
    font-weight: normal;
    font-size: 1rem
}

.footer {
    background-color: var(--card-bg-light);
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--border-color-light)
}

[data-theme="dark"] .footer {
    background-color: var(--card-bg-dark);
    border-top-color: var(--border-color-dark)
}

.copyright {
    margin: 0;
    font-size: 0.9rem;
    color: #777
}

[data-theme="dark"] .copyright {
    color: #888
}

@media (max-width:1200px) {
    .video-grid {
        grid-template-columns: repeat(4, 1fr)
    }
}

@media (max-width:992px) {
    .video-grid {
        grid-template-columns: repeat(3, 1fr)
    }
}

@media (max-width:768px) {
    .category-nav {
        top: 60px
    }

    .video-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px
    }

    .modal-content {
        max-width: 100%;
        max-height: 100%;
        border-radius: 0
    }

    .video-wrapper {
        border-radius: 0
    }

    .close-btn {
        top: 20px;
        right: 20px;
        background: rgba(0, 0, 0, 0.5);
        width: 40px;
        height: 40px;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem
    }

    .modal-video-title {
        position: absolute;
        bottom: 40px;
        left: 20px;
        text-align: left;
        text-shadow: 0 1px 3px rgba(0, 0, 0, 0.8);
        margin: 0;
        pointer-events: none
    }
}

@media (max-width:576px) {
    .features-grid {
        grid-template-columns: 1fr
    }

    .section-title {
        margin-bottom: 30px
    }

    .swiper {
        border-radius: 0
    }

    .container {
        padding: 0 15px
    }

    .hero-title {
        font-size: 2.2rem
    }

    .hero-subtitle {
        font-size: 1.1rem
    }

    .btn-back {
        width: 35px;
        height: 35px
    }

    .tab-btn {
        padding: 6px 15px;
        font-size: 0.85rem
    }
}


/* 新增：置顶标签样式 */
.top-tag {
    position: absolute;
    top: 0;
    left: 0;
    background-color: #000000; /* 黑底 */
    color: #ff9900;            /* 橙字 */
    padding: 4px 8px;
    font-size: 12px;
    font-weight: bold;
    border-bottom-right-radius: 8px; /* 右下角圆角 */
    z-index: 10; /* 确保在海报上方 */
    box-shadow: 2px 2px 5px rgba(0,0,0,0.5);
}