/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #FF6B35;
    --secondary-color: #00D4FF;
    --bg-dark: #0F0F1E;
    --bg-darker: #07070D;
    --bg-card: #1A1A2E;
    --text-primary: #FFFFFF;
    --text-secondary: #B0B0C3;
    --border-color: #2A2A3E;
    --success-color: #00C853;
    --error-color: #FF3B30;
    --warning-color: #FFB800;
}

/* 日间模式主题变量 */
[data-theme="light"] {
    --primary-color: #FF6B35;
    --secondary-color: #0096D6;
    --bg-dark: #F5F5F7;
    --bg-darker: #FFFFFF;
    --bg-card: #FFFFFF;
    --text-primary: #1D1D1F;
    --text-secondary: #6E6E73;
    --border-color: #D2D2D7;
    --success-color: #00C853;
    --error-color: #FF3B30;
    --warning-color: #FFB800;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部导航 */
.site-header {
    background: var(--bg-darker);
    border-bottom: 1px solid var(--border-color);
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

[data-theme="light"] .site-header {
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 30px;
}

.logo a {
    font-size: 24px;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s;
}

.logo a:hover {
    color: var(--secondary-color);
}

.main-nav {
    display: flex;
    gap: 30px;
}

.main-nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 16px;
    transition: all 0.3s;
    padding: 8px 15px;
    border-radius: 8px;
}

.main-nav a:hover,
.main-nav a.active {
    color: var(--primary-color);
    background: rgba(255, 107, 53, 0.1);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 15px;
}

.search-box form {
    display: flex;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 25px;
    overflow: hidden;
    transition: all 0.3s;
}

.search-box form:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.1);
}

.search-box input {
    background: transparent;
    border: none;
    padding: 10px 20px;
    color: var(--text-primary);
    outline: none;
    width: 250px;
}

.search-box button {
    background: transparent;
    border: none;
    padding: 10px 15px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
}

.search-box button:hover {
    transform: scale(1.1);
}

/* 主题切换按钮 */
.theme-toggle-btn {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.theme-toggle-btn:hover {
    border-color: var(--primary-color);
    transform: rotate(180deg);
}

.theme-icon {
    font-size: 20px;
    display: block;
    transition: opacity 0.3s ease;
}

.moon-icon {
    display: none;
}

[data-theme="light"] .theme-toggle-btn {
    background: var(--bg-card);
}

[data-theme="light"] .sun-icon {
    display: none;
}

[data-theme="light"] .moon-icon {
    display: block;
}

.user-menu {
    position: relative;
}

.user-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 25px;
    padding: 8px 15px;
    cursor: pointer;
    color: var(--text-primary);
    transition: all 0.3s;
}

.user-btn:hover {
    border-color: var(--primary-color);
}

.user-avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    object-fit: cover;
}

.verification-badge {
    width: 18px;
    height: 18px;
    margin-left: 5px;
}

.user-dropdown {
    position: absolute;
    top: 110%;
    right: 0;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 8px;
    min-width: 180px;
    display: none;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
    transition: opacity 0.2s ease, visibility 0.2s ease;
    opacity: 0;
    visibility: hidden;
}

.user-menu:hover .user-dropdown,
.user-dropdown:hover {
    display: block;
    opacity: 1;
    visibility: visible;
}

/* 增加下拉菜单可悬停区域 */
.user-menu::after {
    content: '';
    position: absolute;
    top: 100%;
    right: 0;
    width: 100%;
    height: 20px;
    background: transparent;
}

.user-dropdown a {
    display: block;
    padding: 12px 15px;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: 8px;
    transition: all 0.3s;
}

.user-dropdown a:hover {
    background: rgba(255, 107, 53, 0.1);
    color: var(--primary-color);
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 10px 24px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 14px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), #FF8C61);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(255, 107, 53, 0.4);
}

.btn-secondary {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.btn-secondary:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-block {
    display: block;
    width: 100%;
    text-align: center;
}

/* 公告栏 */
.announcement-bar {
    background: linear-gradient(135deg, rgba(255, 107, 53, 0.2), rgba(0, 212, 255, 0.2));
    border-bottom: 1px solid var(--border-color);
    padding: 12px 0;
    text-align: center;
}

.announcement-bar .container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.announcement-icon {
    font-size: 20px;
}

/* 主内容区 */
.main-content {
    flex: 1;
    padding: 30px 0;
}

/* 筛选栏 */
.filter-bar {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 30px;
    transition: all 0.3s ease;
}

[data-theme="light"] .filter-bar {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}

.filter-group:last-child {
    margin-bottom: 0;
}

.filter-group label {
    font-weight: 500;
    min-width: 60px;
    color: var(--text-secondary);
}

.filter-group a {
    padding: 6px 16px;
    border-radius: 20px;
    background: var(--bg-darker);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: all 0.3s;
    border: 1px solid transparent;
}

.filter-group a:hover {
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.filter-group a.active {
    background: linear-gradient(135deg, var(--primary-color), #FF8C61);
    color: white;
}

/* 视频网格 */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 25px;
}

.video-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    transition: all 0.3s;
    cursor: pointer;
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.3);
    border-color: var(--primary-color);
}

[data-theme="light"] .video-card {
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

[data-theme="light"] .video-card:hover {
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

.video-cover {
    position: relative;
    display: block;
    padding-top: 140%;
    overflow: hidden;
    background: var(--bg-darker);
}

.video-cover img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: all 0.3s;
}

.video-card:hover .video-cover img {
    transform: scale(1.1);
}

.video-badge {
    position: absolute;
    top: 10px;
    left: 10px;
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
    z-index: 1;
}

.video-badge.ongoing {
    background: linear-gradient(135deg, var(--primary-color), #FF8C61);
}

.video-badge.completed {
    background: linear-gradient(135deg, var(--success-color), #00E676);
}

.video-rating {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(0, 0, 0, 0.8);
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
}

.video-info {
    padding: 15px;
}

.video-title {
    font-size: 16px;
    margin-bottom: 8px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.video-title a {
    color: var(--text-primary);
    text-decoration: none;
    transition: all 0.3s;
}

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

.video-progress {
    font-size: 13px;
    color: var(--secondary-color);
    margin-bottom: 5px;
}

.video-meta {
    font-size: 12px;
    color: var(--text-secondary);
    display: flex;
    justify-content: space-between;
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
    grid-column: 1 / -1;
}

/* 认证页面 */
.auth-page {
    background: linear-gradient(135deg, var(--bg-darker) 0%, var(--bg-dark) 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.auth-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
}

.auth-box {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    padding: 40px;
    width: 100%;
    max-width: 480px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    transition: all 0.3s ease;
}

[data-theme="light"] .auth-box {
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

.auth-header {
    text-align: center;
    margin-bottom: 30px;
}

.auth-header h1 {
    font-size: 28px;
    margin-bottom: 10px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.auth-header p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* 表单样式 */
.auth-form {
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.input-wrapper {
    display: flex;
    align-items: center;
    background: var(--bg-darker);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    padding: 12px 16px;
    transition: all 0.3s;
}

.input-wrapper:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(255, 107, 53, 0.1);
}

.input-wrapper.error {
    border-color: var(--error-color);
}

.input-icon {
    font-size: 20px;
    margin-right: 12px;
}

.input-wrapper input {
    flex: 1;
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 15px;
    outline: none;
}

.input-wrapper input::placeholder {
    color: var(--text-secondary);
}

.input-error {
    display: block;
    color: var(--error-color);
    font-size: 13px;
    margin-top: 8px;
    margin-left: 16px;
}

/* 验证码样式 */
.captcha-wrapper {
    display: flex;
    gap: 12px;
    align-items: flex-start;
}

.captcha-input {
    flex: 1;
}

.captcha-image-wrapper {
    display: flex;
    gap: 8px;
    align-items: center;
}

.captcha-img {
    height: 48px;
    border-radius: 8px;
    border: 2px solid var(--border-color);
    cursor: pointer;
    transition: all 0.3s;
}

.captcha-img:hover {
    border-color: var(--primary-color);
}

.captcha-refresh {
    background: var(--bg-darker);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    border-radius: 8px;
    width: 48px;
    height: 48px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
}

.captcha-refresh:hover {
    background: var(--primary-color);
    border-color: var(--primary-color);
    transform: rotate(180deg);
}

/* 复选框样式 */
.checkbox-wrapper {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    color: var(--text-secondary);
}

.checkbox-wrapper input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
}

.checkbox-wrapper a {
    color: var(--primary-color);
    text-decoration: none;
}

.checkbox-wrapper a:hover {
    text-decoration: underline;
}

.form-options {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.link-secondary {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
}

.link-secondary:hover {
    color: var(--primary-color);
}

/* 提示框 */
.alert {
    padding: 15px 20px;
    border-radius: 12px;
    margin-bottom: 20px;
    font-size: 14px;
}

.alert-error {
    background: rgba(255, 59, 48, 0.1);
    border: 1px solid var(--error-color);
    color: var(--error-color);
}

.alert-success {
    background: rgba(0, 200, 83, 0.1);
    border: 1px solid var(--success-color);
    color: var(--success-color);
}

.alert-warning {
    background: rgba(255, 184, 0, 0.1);
    border: 1px solid var(--warning-color);
    color: var(--warning-color);
}

/* 页脚 */
.auth-footer {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.auth-footer p {
    color: var(--text-secondary);
    font-size: 14px;
}

.auth-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.auth-footer a:hover {
    text-decoration: underline;
}

.site-footer {
    background: var(--bg-darker);
    border-top: 1px solid var(--border-color);
    padding: 20px 0;
    text-align: center;
    color: var(--text-secondary);
    font-size: 13px;
    margin-top: auto;
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .video-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 20px;
    }
    
    .container {
        padding: 0 16px;
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-wrap: wrap;
        gap: 15px;
    }
    
    .logo a {
        font-size: 20px;
    }
    
    .main-nav {
        order: 3;
        width: 100%;
        justify-content: space-around;
        margin-top: 10px;
        gap: 5px;
    }
    
    .main-nav a {
        padding: 6px 12px;
        font-size: 14px;
    }
    
    .header-actions {
        gap: 10px;
    }
    
    .search-box form {
        width: auto;
    }
    
    .search-box input {
        width: 120px;
        padding: 8px 12px;
        font-size: 14px;
    }
    
    .theme-toggle-btn {
        width: 38px;
        height: 38px;
    }
    
    .theme-icon {
        font-size: 18px;
    }
    
    .user-btn {
        padding: 6px 12px;
        font-size: 14px;
    }
    
    .user-btn span {
        display: none;
    }
    
    .user-avatar {
        width: 28px;
        height: 28px;
    }
    
    .btn {
        padding: 8px 16px;
        font-size: 13px;
    }
    
    /* 公告栏 */
    .announcement-bar {
        padding: 10px 0;
        font-size: 14px;
    }
    
    .announcement-icon {
        font-size: 16px;
    }
    
    /* 主内容 */
    .main-content {
        padding: 20px 0;
    }
    
    /* 筛选栏 */
    .filter-bar {
        padding: 15px;
    }
    
    .filter-group {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    .filter-group label {
        width: 100%;
        margin-bottom: 5px;
    }
    
    .filter-group a {
        padding: 5px 12px;
        font-size: 13px;
    }
    
    /* 视频网格 */
    .video-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 15px;
    }
    
    .video-info {
        padding: 12px;
    }
    
    .video-title {
        font-size: 14px;
        margin-bottom: 6px;
    }
    
    .video-progress {
        font-size: 12px;
    }
    
    .video-meta {
        font-size: 11px;
    }
    
    /* 认证页面 */
    .auth-box {
        padding: 30px 20px;
        max-width: 420px;
    }
    
    .auth-header h1 {
        font-size: 24px;
    }
    
    .captcha-wrapper {
        flex-direction: column;
    }
    
    .captcha-image-wrapper {
        width: 100%;
        justify-content: space-between;
    }
    
    /* 页脚 */
    .site-footer {
        font-size: 12px;
        padding: 15px 0;
    }
    
    .site-footer p {
        line-height: 1.8;
    }
    
    .site-footer a {
        display: inline-block;
        margin: 3px 5px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 12px;
    }
    
    .site-header {
        padding: 12px 0;
    }
    
    .header-content {
        gap: 10px;
    }
    
    .logo a {
        font-size: 18px;
    }
    
    .main-nav {
        gap: 0;
        margin-top: 8px;
    }
    
    .main-nav a {
        padding: 5px 8px;
        font-size: 13px;
        flex: 1;
        text-align: center;
    }
    
    .header-actions {
        gap: 8px;
        flex-wrap: wrap;
    }
    
    .search-box {
        order: 3;
        width: 100%;
    }
    
    .search-box form {
        width: 100%;
    }
    
    .search-box input {
        width: 100%;
        flex: 1;
    }
    
    .theme-toggle-btn {
        width: 36px;
        height: 36px;
    }
    
    .theme-icon {
        font-size: 16px;
    }
    
    .btn {
        padding: 8px 14px;
        font-size: 12px;
    }
    
    /* 公告栏 */
    .announcement-bar .container {
        flex-direction: column;
        gap: 5px;
        text-align: center;
        font-size: 13px;
    }
    
    /* 筛选栏 */
    .filter-bar {
        padding: 12px;
    }
    
    .filter-group {
        margin-bottom: 12px;
    }
    
    .filter-group label {
        font-size: 13px;
    }
    
    .filter-group a {
        padding: 4px 10px;
        font-size: 12px;
    }
    
    /* 视频网格 */
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
    
    .video-badge {
        font-size: 10px;
        padding: 3px 8px;
    }
    
    .video-rating {
        font-size: 10px;
        padding: 3px 8px;
    }
    
    .video-info {
        padding: 10px;
    }
    
    .video-title {
        font-size: 13px;
        margin-bottom: 5px;
    }
    
    .video-progress {
        font-size: 11px;
    }
    
    .video-meta {
        font-size: 10px;
    }
    
    /* 认证页面 */
    .auth-container {
        padding: 20px 12px;
    }
    
    .auth-box {
        padding: 25px 16px;
        border-radius: 16px;
    }
    
    .auth-header h1 {
        font-size: 22px;
    }
    
    .auth-header p {
        font-size: 13px;
    }
    
    .form-group {
        margin-bottom: 16px;
    }
    
    .input-wrapper {
        padding: 10px 14px;
    }
    
    .input-wrapper input {
        font-size: 14px;
    }
    
    .input-icon {
        font-size: 18px;
        margin-right: 10px;
    }
    
    .captcha-img {
        height: 44px;
    }
    
    .captcha-refresh {
        width: 44px;
        height: 44px;
        font-size: 16px;
    }
    
    .checkbox-wrapper {
        font-size: 12px;
    }
    
    .alert {
        padding: 12px 16px;
        font-size: 13px;
    }
    
    /* 页脚 */
    .site-footer {
        font-size: 11px;
        padding: 12px 0;
    }
    
    .site-footer a {
        display: block;
        margin: 5px 0;
    }
}

/* 超小屏幕优化 */
@media (max-width: 360px) {
    .logo a {
        font-size: 16px;
    }
    
    .main-nav a {
        padding: 4px 6px;
        font-size: 12px;
    }
    
    .video-grid {
        gap: 10px;
    }
    
    .video-info {
        padding: 8px;
    }
    
    .video-title {
        font-size: 12px;
    }
    
    .auth-box {
        padding: 20px 12px;
    }
}

/* 横屏模式优化 */
@media (max-width: 768px) and (orientation: landscape) {
    .auth-container {
        padding: 20px 12px;
    }
    
    .auth-box {
        max-width: 600px;
    }
    
    .video-grid {
        grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    }
}