/* 91网 全局样式 - 外部CSS文件 */
:root {
    --primary-color: #e60012;
    --primary-dark: #b30010;
    --text-color: #333;
    --text-light: #666;
    --bg-color: #f5f5f5;
    --white: #fff;
    --border-color: #ddd;
    --shadow: 0 2px 8px rgba(0,0,0,0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Helvetica, Arial, sans-serif;
    color: var(--text-color);
    background-color: var(--bg-color);
    line-height: 1.7;
    font-size: 15px;
}

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

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

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

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

/* ===== Header ===== */
header {
    background-color: var(--white);
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
    padding: 12px 0;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.logo {
    font-size: 22px;
    font-weight: bold;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo img {
    height: 38px;
    width: auto;
    vertical-align: middle;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 5px;
    flex-wrap: wrap;
}

nav a {
    font-size: 14px;
    font-weight: 500;
    padding: 6px 10px;
    border-radius: 4px;
    transition: background 0.2s;
}

nav a:hover {
    background-color: #fff0f0;
    color: var(--primary-color);
}

/* ===== Search Box ===== */
.search-box {
    padding: 10px 0;
    text-align: center;
    border-top: 1px solid #f0f0f0;
    margin-top: 8px;
}

.search-box form {
    display: inline-flex;
    width: 100%;
    max-width: 500px;
}

.search-box input {
    flex: 1;
    padding: 10px 15px;
    border: 2px solid var(--border-color);
    border-right: none;
    border-radius: 4px 0 0 4px;
    outline: none;
    font-size: 14px;
    transition: border-color 0.2s;
}

.search-box input:focus {
    border-color: var(--primary-color);
}

.search-box button {
    padding: 10px 22px;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
    font-size: 14px;
    font-weight: bold;
    transition: background 0.2s;
}

.search-box button:hover {
    background-color: var(--primary-dark);
}

/* ===== Banner ===== */
.banner {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--white);
    text-align: center;
    padding: 60px 20px;
}

.banner h1 {
    font-size: 34px;
    margin-bottom: 12px;
    text-shadow: 0 1px 3px rgba(0,0,0,0.2);
}

.banner p {
    font-size: 17px;
    margin-bottom: 24px;
    opacity: 0.9;
}

.btn-primary {
    display: inline-block;
    padding: 12px 32px;
    background: var(--white);
    color: var(--primary-color);
    border-radius: 4px;
    font-weight: bold;
    font-size: 15px;
    margin: 5px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.2);
    color: var(--primary-color);
}

.btn-outline {
    display: inline-block;
    padding: 12px 32px;
    background: transparent;
    color: var(--white);
    border: 2px solid var(--white);
    border-radius: 4px;
    font-weight: bold;
    font-size: 15px;
    margin: 5px;
    transition: background 0.2s;
}

.btn-outline:hover {
    background: rgba(255,255,255,0.15);
    color: var(--white);
}

/* ===== Section ===== */
section {
    background-color: var(--white);
    padding: 35px;
    margin-bottom: 25px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.section-title {
    font-size: 22px;
    font-weight: bold;
    margin-bottom: 20px;
    border-left: 4px solid var(--primary-color);
    padding-left: 12px;
    color: var(--text-color);
}

/* ===== Video Cards ===== */
.video-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 18px;
}

.video-card {
    position: relative;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
    cursor: pointer;
    transition: transform 0.25s, box-shadow 0.25s;
    background: var(--white);
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.12);
}

.video-thumb {
    width: 100%;
    height: 155px;
    background-color: #e0e0e0;
    position: relative;
    overflow: hidden;
}

.video-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}

.video-card:hover .video-thumb img {
    transform: scale(1.05);
}

.play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 52px;
    height: 52px;
    background-color: rgba(0, 0, 0, 0.65);
    border-radius: 50%;
    display: none;
    justify-content: center;
    align-items: center;
    transition: background 0.2s;
}

.play-btn::after {
    content: '';
    width: 0;
    height: 0;
    border-top: 11px solid transparent;
    border-bottom: 11px solid transparent;
    border-left: 17px solid #fff;
    margin-left: 5px;
}

.video-card:hover .play-btn {
    display: flex;
}

.video-info {
    padding: 12px 14px;
}

.video-title {
    font-size: 14px;
    font-weight: bold;
    margin-bottom: 8px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-color);
}

.video-meta {
    font-size: 12px;
    color: #999;
    display: flex;
    justify-content: space-between;
}

/* ===== FAQ ===== */
.faq-item {
    margin-bottom: 18px;
    border-bottom: 1px dashed var(--border-color);
    padding-bottom: 18px;
}

.faq-q {
    font-weight: bold;
    margin-bottom: 8px;
    color: var(--primary-color);
    font-size: 15px;
}

.faq-a {
    color: var(--text-light);
    line-height: 1.8;
}

/* ===== Reviews ===== */
.review-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
}

.review-card {
    background-color: #fafafa;
    padding: 18px;
    border-radius: 8px;
    border: 1px solid #f0f0f0;
}

.review-user {
    font-weight: bold;
    margin-bottom: 8px;
    color: var(--text-color);
}

.review-content {
    color: var(--text-light);
    line-height: 1.7;
}

/* ===== Footer ===== */
footer {
    background-color: #2d2d2d;
    color: #bbb;
    text-align: center;
    padding: 35px 0;
    margin-top: 40px;
}

footer a {
    color: #bbb;
    transition: color 0.2s;
}

footer a:hover {
    color: var(--white);
}

.footer-links {
    margin-bottom: 18px;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 5px;
}

.footer-links a {
    margin: 0 8px;
    font-size: 14px;
}

.footer-info p {
    margin: 5px 0;
    font-size: 13px;
    color: #999;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .review-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .header-inner {
        flex-direction: column;
        align-items: flex-start;
    }
    nav ul {
        gap: 3px;
    }
    nav a {
        font-size: 13px;
        padding: 5px 8px;
    }
    .banner h1 {
        font-size: 24px;
    }
    .banner p {
        font-size: 15px;
    }
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    section {
        padding: 20px;
    }
    .section-title {
        font-size: 18px;
    }
}

@media (max-width: 480px) {
    .video-grid {
        grid-template-columns: 1fr;
    }
    .container {
        padding: 0 12px;
    }
}