/* ===== 全局重置 & 基础 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    background: #f8faff;
    color: #2d3e4f;
    line-height: 1.6;
    padding: 0 0 20px 0;
}
.container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 20px;
}
a {
    color: #2a7de1;
    text-decoration: none;
    transition: color 0.2s;
}
a:hover {
    color: #ff6b6b;
}

/* ===== 头部 ===== */
header {
    background: linear-gradient(135deg, #1a2a3a, #0f1a26);
    color: #fff;
    padding: 16px 0;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}
.logo a {
    font-size: 28px;
    font-weight: 700;
    color: #fff;
    letter-spacing: 1px;
}
.logo i {
    color: #ffd93d;
    margin-right: 8px;
}
nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}
nav ul li a {
    color: #cbd5e1;
    font-size: 16px;
    padding: 6px 12px;
    border-radius: 20px;
    transition: 0.3s;
}
nav ul li a:hover {
    background: rgba(255,255,255,0.15);
    color: #fff;
}

/* ===== 收藏提示 ===== */
.bookmark {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: #cbd5e1;
    background: rgba(255, 255, 255, 0.08);
    padding: 6px 14px;
    border-radius: 30px;
    white-space: nowrap;
}
.bookmark i {
    font-size: 16px;
}
.bookmark a {
    color: #ffd93d !important;
    font-weight: 600;
}
.bookmark a:hover {
    color: #fff !important;
    text-decoration: underline;
}

/* ===== 主标题 ===== */
.page-title {
    font-size: 2.2rem;
    margin: 30px 0 10px;
    display: flex;
    align-items: center;
    gap: 12px;
    color: #1a2a3a;
}
.page-title i {
    color: #ff6b6b;
}
.sub-title {
    color: #5a6f80;
    font-size: 1.1rem;
    margin-bottom: 30px;
    border-left: 4px solid #2a7de1;
    padding-left: 16px;
}

/* ===== 视频网格 ===== */
.video-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 28px 20px;
    margin-bottom: 40px;
}

@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) {
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
}
@media (max-width: 480px) {
    .video-grid {
        grid-template-columns: repeat(2, 1fr);  /* 改为两列 */
        gap: 12px;
    }
}

.video-card {
    background: #ffffff;
    border-radius: 18px;
    box-shadow: 0 6px 20px rgba(0, 20, 40, 0.08);
    overflow: hidden;
    transition: transform 0.25s ease, box-shadow 0.3s;
    display: flex;
    flex-direction: column;
}
.video-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 14px 35px rgba(0, 20, 40, 0.15);
}

.img-link {
    display: block;
    position: relative;
    width: 100%;
    padding-top: 166.67%;
    overflow: hidden;
    background: #e9edf2;
}
.img-wrapper {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}
.img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.4s;
}
.video-card:hover .img-wrapper img {
    transform: scale(1.04);
}

.play-icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: rgba(255, 255, 255, 0.9);
    font-size: 52px;
    text-shadow: 0 4px 12px rgba(0,0,0,0.4);
    transition: 0.3s;
    pointer-events: none;
}
.video-card:hover .play-icon {
    font-size: 62px;
    color: #ffd93d;
}

.video-card h3 {
    font-size: 1.1rem;
    padding: 14px 16px 4px;
    font-weight: 600;
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
    line-height: 1.4;
}
.video-card h3 a {
    color: #1a2a3a;
}
.video-card h3 a:hover {
    color: #ff6b6b;
}

.video-card p {
    padding: 0 16px 8px;
    font-size: 0.9rem;
    color: #5a6f80;
    flex: 1;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    text-overflow: ellipsis;
    line-height: 1.5;
}

.video-card .tags {
    padding: 0 16px 16px;
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}
.video-card .tags a {
    background: #eef3f8;
    padding: 2px 12px;
    border-radius: 30px;
    font-size: 0.75rem;
    color: #2a7de1;
    transition: 0.2s;
}
.video-card .tags a:hover {
    background: #2a7de1;
    color: #fff;
}

/* ===== 标签云 ===== */
.tag-cloud {
    background: #ffffff;
    border-radius: 24px;
    padding: 30px 0 25px;
    margin: 20px 0 30px;
    box-shadow: 0 4px 18px rgba(0,0,0,0.04);
}
.tag-cloud h3 {
    font-size: 1.5rem;
    margin-bottom: 18px;
    color: #1a2a3a;
}
.tag-cloud h3 i {
    color: #ff6b6b;
    margin-right: 10px;
}
.cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 10px 14px;
    justify-content: center;
}
.cloud a {
    background: #f0f4fa;
    padding: 6px 18px;
    border-radius: 40px;
    font-size: 0.9rem;
    color: #1a2a3a;
    transition: 0.2s;
    border: 1px solid transparent;
}
.cloud a:hover {
    background: #2a7de1;
    color: #fff;
    border-color: #2a7de1;
    transform: scale(1.02);
}

/* ===== 页脚 ===== */
footer {
    background: #0f1a26;
    color: #a0b3c4;
    padding: 24px 0;
    text-align: center;
    border-radius: 30px 30px 0 0;
    margin-top: 30px;
}
footer a {
    color: #ffd93d;
}
footer a:hover {
    color: #fff;
}
footer p {
    margin: 6px 0;
    font-size: 0.95rem;
}

/* ===== 响应式调整 ===== */
@media (max-width: 768px) {
    header .container {
        flex-direction: column;
        align-items: stretch;
        gap: 12px;
    }
    nav ul {
        justify-content: center;
        gap: 12px;
    }
    .bookmark {
        margin-left: 0;
        justify-content: center;
        font-size: 13px;
        padding: 4px 12px;
    }
    .page-title {
        font-size: 1.6rem;
    }
    .play-icon {
        font-size: 40px;
    }
    .cloud a {
        font-size: 0.8rem;
        padding: 4px 14px;
    }
}

@media (max-width: 480px) {

    .bookmark {
        font-size: 12px;
        padding: 4px 10px;
    }
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
    .video-card h3 {
        font-size: 0.85rem;
        padding: 8px 10px 2px;
    }
    .video-card p {
        font-size: 0.75rem;
        padding: 0 10px 6px;
    }
    .video-card .tags {
        padding: 0 10px 10px;
    }
    .video-card .tags a {
        font-size: 0.65rem;
        padding: 1px 8px;
    }
    .play-icon {
        font-size: 30px;
    }
    .video-card:hover .play-icon {
        font-size: 38px;
    }
}