:root {
    --primary-color: #00f2ff;
    --secondary-color: #7000ff;
    --bg-dark: #050505;
    --text-light: #ffffff;
    --accent-color: #ff00c8;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'PingFang SC', 'Microsoft YaHei', sans-serif;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-light);
    overflow-x: hidden;
    line-height: 1.6;
}

/* 导航栏 */
header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(5, 5, 5, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

.logo img {
    height: 40px;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 2rem;
}

nav ul li a {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

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

/* 搜索框 */
.search-box {
    margin: 10px auto;
    max-width: 600px;
    display: flex;
    padding: 0 20px;
}

.search-box input {
    flex: 1;
    padding: 10px 20px;
    border-radius: 25px 0 0 25px;
    border: 1px solid var(--primary-color);
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

.search-box button {
    padding: 10px 25px;
    border-radius: 0 25px 25px 0;
    border: none;
    background: var(--primary-color);
    color: black;
    cursor: pointer;
}

/* Banner */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.5)), url('../images/banner.jpg') center/cover no-repeat;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 0 20px;
}

.hero h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
    background: linear-gradient(to right, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: fadeInUp 1s ease-out;
}

.hero p {
    font-size: 1.5rem;
    max-width: 800px;
    margin-bottom: 2rem;
}

.btn {
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: bold;
    transition: transform 0.3s, box-shadow 0.3s;
    display: inline-block;
}

.btn-primary {
    background: var(--primary-color);
    color: black;
}

.btn-primary:hover {
    transform: scale(1.05);
    box-shadow: 0 0 20px var(--primary-color);
}

/* 视频卡片 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    padding: 4rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.video-card {
    position: relative;
    border-radius: 15px;
    overflow: hidden;
    background: #111;
    transition: transform 0.3s;
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-10px);
}

.video-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 200px;
    background: rgba(0,0,0,0.4);
    display: flex;
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s;
}

.video-card:hover .play-overlay {
    opacity: 1;
}

.play-btn {
    width: 60px;
    height: 60px;
    background: var(--primary-color);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.play-btn::after {
    content: '';
    border-style: solid;
    border-width: 10px 0 10px 20px;
    border-color: transparent transparent transparent black;
    margin-left: 5px;
}

.video-info {
    padding: 1.5rem;
}

.video-info h3 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.video-stats {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: #888;
}

/* FAQ & Reviews */
.section-title {
    text-align: center;
    margin: 4rem 0 2rem;
    font-size: 2.5rem;
}

.faq-container, .reviews-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

.faq-item {
    background: rgba(255,255,255,0.05);
    margin-bottom: 1rem;
    padding: 1.5rem;
    border-radius: 10px;
}

.review-item {
    background: rgba(255,255,255,0.05);
    margin-bottom: 1rem;
    padding: 1.5rem;
    border-radius: 10px;
    border-left: 4px solid var(--secondary-color);
}

/* Footer */
footer {
    background: #000;
    padding: 4rem 2rem 2rem;
    text-align: center;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.footer-links {
    margin-bottom: 2rem;
}

.footer-links a {
    color: #888;
    text-decoration: none;
    margin: 0 1rem;
}

/* Animations */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 768px) {
    .nav-container { flex-direction: column; }
    nav ul { margin-top: 1rem; }
    nav ul li { margin: 0 0.5rem; }
    .hero h1 { font-size: 2.5rem; }
}