/* iOS风格全局变量定义 */
:root {
    --primary-color: #007AFF;
    --secondary-color: #5856D6;
    --accent-color: #FF2D92;
    --success-color: #34C759;
    --warning-color: #FF9500;
    --danger-color: #FF3B30;
    --dark-bg: #1C1C1E;
    --darker-bg: #0C0C0E;
    --light-bg: #F2F2F7;
    --light-text: #FFFFFF;
    --dark-text: #1C1C1E;
    --nav-width: 280px;
    --nav-collapsed-width: 80px;
    --control-size: 80px;
    --progress-ring-size: 88px;
    --volume-slider-width: 120px;
    --volume-slider-height: 40px;
    --transition-speed: 0.3s;
    --border-radius: 12px;
    --border-radius-small: 8px;
    
    /* iOS特有变量 */
    --ios-blur: blur(20px);
    --ios-backdrop: rgba(255, 255, 255, 0.8);
    --ios-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
    --ios-border: 1px solid rgba(255, 255, 255, 0.2);
    --ios-text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

/* iOS风格白天模式变量 */
.light-mode {
    --bg-color: var(--light-bg);
    --text-color: var(--dark-text);
    --nav-bg: rgba(255, 255, 255, 0.8);
    --border-color: rgba(0, 0, 0, 0.1);
    --control-bg: rgba(255, 255, 255, 0.8);
    --comment-bg: rgba(255, 255, 255, 0.8);
    --shadow-color: rgba(0, 0, 0, 0.1);
    --progress-bg-color: rgba(0, 0, 0, 0.1);
    --volume-popup-bg: rgba(255, 255, 255, 0.9);
    --profile-bg: rgba(255, 255, 255, 0.8);
}

/* iOS风格夜间模式变量 */
.dark-mode {
    --bg-color: var(--dark-bg);
    --text-color: var(--light-text);
    --nav-bg: rgba(28, 28, 30, 0.8);
    --border-color: rgba(255, 255, 255, 0.1);
    --control-bg: rgba(28, 28, 30, 0.8);
    --comment-bg: rgba(28, 28, 30, 0.8);
    --shadow-color: rgba(0, 0, 0, 0.3);
    --progress-bg-color: rgba(255, 255, 255, 0.1);
    --volume-popup-bg: rgba(28, 28, 30, 0.9);
    --profile-bg: rgba(28, 28, 30, 0.8);
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 主容器布局 */
.app-container {
    display: flex;
    height: 100vh;
    width: 100vw;
}

/* ================= iOS风格左侧导航栏 ================= */
.side-nav {
    width: var(--nav-width);
    height: 100%;
    background: var(--nav-bg);
    backdrop-filter: var(--ios-blur);
    -webkit-backdrop-filter: var(--ios-blur);
    border-right: var(--ios-border);
    display: flex;
    flex-direction: column;
    padding: 15px 0;
    transition: width var(--transition-speed);
    position: relative;
    z-index: 100;
    flex-shrink: 0;
    box-shadow: var(--ios-shadow);
}

.side-nav.collapsed {
    width: var(--nav-collapsed-width);
}

.nav-header {
    display: flex;
    align-items: center;
    padding: 0 15px 15px;
    border-bottom: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.nav-icon {
    font-size: 24px;
    color: var(--accent-color);
    margin-right: 12px;
    flex-shrink: 0;
    transition: opacity var(--transition-speed);
}

.nav-title {
    font-size: 16px;
    font-weight: 500;
    white-space: nowrap;
    transition: opacity var(--transition-speed);
}

.side-nav.collapsed .nav-icon,
.side-nav.collapsed .nav-title,
.side-nav.collapsed .source-text,
.side-nav.collapsed .user-text,
.side-nav.collapsed .profile-text,
.side-nav.collapsed .theme-text,
.side-nav.collapsed .logout-text {
    opacity: 0;
    pointer-events: none;
    width: 0;
    height: 0;
    overflow: hidden;
    margin: 0;
}

.collapse-nav-btn {
    position: absolute;
    right: 10px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    width: 24px;
    height: 24px;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 4px;
    transition: all var(--transition-speed);
}

.collapse-nav-btn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

/* 视频源列表 */
.source-list {
    list-style: none;
    margin-top: 15px;
    flex-grow: 1;
    overflow-y: auto;
    padding: 0 5px;
}

.source-item {
    margin: 4px 0;
    cursor: pointer;
    transition: all var(--transition-speed);
    border-radius: var(--border-radius);
    position: relative;
    overflow: hidden;
}

.source-item:hover {
    background-color: rgba(67, 97, 238, 0.1);
}

.source-item.active {
    background-color: rgba(67, 97, 238, 0.2);
}

.source-content {
    display: flex;
    align-items: center;
    padding: 12px 15px;
}

.source-icon {
    width: 24px;
    height: 24px;
    margin-right: 12px;
    object-fit: contain;
    flex-shrink: 0;
    font-size: 18px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.source-text {
    font-size: 14px;
    white-space: nowrap;
    transition: opacity var(--transition-speed);
}

/* 用户控制区 */
.user-controls {
    padding: 15px;
    border-top: 1px solid var(--border-color);
    overflow: hidden;
}

.user-info, .profile-btn, .theme-toggle, .logout-btn {
    display: flex;
    align-items: center;
    padding: 10px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-speed);
    background: none;
    border: none;
    color: inherit;
    font-size: 14px;
    width: 100%;
    text-align: left;
    overflow: hidden;
    margin-bottom: 5px;
}

.user-info:hover, .profile-btn:hover, .theme-toggle:hover, .logout-btn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.user-info i, .profile-btn i, .theme-toggle i, .logout-btn i {
    font-size: 18px;
    margin-right: 10px;
    width: 24px;
    text-align: center;
    flex-shrink: 0;
}

.user-text, .profile-text, .theme-text, .logout-text {
    font-size: 14px;
    transition: opacity var(--transition-speed);
}

.logout-btn {
    color: var(--accent-color);
}

.logout-btn:hover {
    background-color: rgba(247, 37, 133, 0.1);
}

/* ================= 主内容区 ================= */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    background-color: var(--darker-bg);
    position: relative;
    transition: margin-left var(--transition-speed);
    overflow: hidden;
    height: 100%;
}

.side-nav.collapsed + .main-content {
    margin-left: calc(var(--nav-collapsed-width) - var(--nav-width));
}

/* 居中视频，两侧留黑边 */
.video-container {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000;
}
#mainVideo {
    max-width: 100vw;
    max-height: 100vh;
    object-fit: contain;
    background: #000;
    box-shadow: none;
    border-radius: 0;
}

/* ================= 视频控制层 ================= */
.video-controls {
    position: absolute;
    left: 0; top: 0; right: 0; bottom: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
}

/* 暂停状态 */
.pause-overlay,
.loading-state,
.error-state {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: auto;
    z-index: 20;
}

.pause-overlay {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}
.pause-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.loading-state {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
}

.error-state {
    background: rgba(0,0,0,0.35);
    border-radius: 16px;
    min-width: 160px;
    min-height: 100px;
    flex-direction: column;
    padding: 20px 32px;
}

.pause-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.pause-icon {
    width: 100px;
    height: 100px;
    background-color: rgba(0, 0, 0, 0.7);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    animation: pulse 2s infinite;
    cursor: pointer;
}

.pause-icon i {
    font-size: 48px;
    color: white;
}

@keyframes pulse {
    0% { transform: scale(1); opacity: 0.7; }
    50% { transform: scale(1.1); opacity: 1; }
    100% { transform: scale(1); opacity: 0.7; }
}

/* 加载状态 */
.loading-state.hidden, 
.error-state.hidden, 
.play-prompt.hidden {
    opacity: 0;
    pointer-events: none;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid rgba(255, 255, 255, 0.2);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 15px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.error-state i, .play-prompt i {
    font-size: 40px;
    color: var(--accent-color);
    margin-bottom: 15px;
}

.retry-btn {
    margin-top: 15px;
    padding: 8px 20px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    transition: all var(--transition-speed);
    pointer-events: auto;
}

.retry-btn:hover {
    background-color: #3a56d4;
    transform: scale(1.05);
}

/* ================= iOS风格右侧控制面板 ================= */
.control-panel {
    position: fixed;
    right: 40px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 32px;
    z-index: 100;
    background: transparent;
    box-shadow: none;
    padding: 0;
    border: none;
    height: auto;
    justify-content: center;
    pointer-events: none;
}
.control-panel .control-btn, .control-panel .volume-control {
    pointer-events: auto;
}

/* 移除画质切换UI相关样式 */
.quality-control, #qualityBtn, #currentQuality, .quality-dropdown, .quality-option {
    display: none !important;
}

/* 修复侧边栏展开时内容被遮挡 */
.side-nav {
    overflow: visible !important;
    z-index: 100 !important;
}

/* 其它相关样式优化可根据实际页面继续补充 */

.control-group {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.like-container {
    margin-bottom: 10px;
}

.progress-ring-container {
    position: relative;
    width: 88px;
    height: 88px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.progress-ring {
    position: absolute;
    top: 0;
    left: 0;
    width: 88px;
    height: 88px;
    z-index: 1;
    pointer-events: none;
}
.progress-bg {
    stroke: var(--progress-bg-color);
    stroke-width: 4;
    fill: none;
}
.progress-fill {
    stroke: var(--primary-color);
    stroke-width: 4;
    fill: none;
    stroke-dasharray: 251;
    stroke-dashoffset: 251;
    transition: stroke-dashoffset 0.3s;
}
/* 只让点赞按钮的宽高和居中生效 */
.progress-ring-container .control-btn {
    position: relative;
    z-index: 2;
    width: 72px;
    height: 72px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0;
    left: 0;
    top: 0;
}

/* 其它按钮恢复原样 */
.control-panel > .control-btn,
.control-panel > .volume-control {
    width: 72px;
    height: 72px;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}
.control-btn {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: var(--control-btn-bg, #23242a);
    border: none;
    color: var(--primary-color);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    transition: background 0.2s, color 0.2s, box-shadow 0.2s;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
    margin-bottom: 0;
    position: relative;
}
.control-btn:hover {
    background: var(--primary-color);
    color: #fff;
    box-shadow: 0 4px 16px rgba(67,97,238,0.12);
}
.control-btn i {
    font-size: 32px;
    margin-bottom: 0;
}
.control-btn .count-text {
    font-size: 20px;
    margin-top: 4px;
    color: #fff;
    font-weight: bold;
    text-shadow: 0 1px 4px rgba(0,0,0,0.18);
}
.control-btn .btn-label {
    position: absolute;
    left: 70px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 15px;
    color: var(--text-color);
    opacity: 0.85;
    white-space: nowrap;
    pointer-events: none;
    font-weight: 400;
}

/* 夜间模式按钮背景 */
body.dark-mode .control-btn {
    background: #23242a;
    color: #fff;
}
body.dark-mode .control-btn:hover {
    background: var(--primary-color);
    color: #fff;
}

/* 恢复音量弹窗式UI样式 */
.volume-control {
    position: relative;
    display: flex;
    align-items: center;
    width: 100%;
    justify-content: flex-start;
}
.volume-popup {
    /* 去除display:flex、align-items、justify-content，避免影响父级布局 */
    width: 160px;
    min-width: 160px;
    max-width: 160px;
    position: absolute;
    right: 100%;
    top: 50%;
    transform: translateY(-50%);
    margin-right: 12px;
    background: var(--volume-popup-bg);
    border-radius: 24px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    padding: 0;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s, left 0.2s, right 0.2s;
    z-index: 9999;
    height: 40px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
.volume-popup.active {
    opacity: 1;
    pointer-events: auto;
}
.volume-popup-inner {
    position: relative;
    width: 100%;
    height: 100%;
    display: block;
}

@media (max-width: 600px) {
    .volume-popup {
        left: 50%;
        right: auto;
        top: auto;
        bottom: 100%;
        transform: translateX(-50%) translateY(-8px);
        margin-right: 0;
        margin-bottom: 8px;
        width: 80vw;
        min-width: 60px;
        max-width: 95vw;
        height: 36px;
    }
}
.volume-slider-bg {
    position: absolute;
    top: 50%;
    left: 16px;
    right: 16px;
    height: 8px;
    background: var(--volume-popup-bg);
    border-radius: 4px;
    z-index: 0;
    transform: translateY(-50%);
}
#volumeSlider {
    position: absolute;
    top: 50%;
    left: 16px;
    right: 16px;
    width: auto;
    transform: translateY(-50%);
    background: transparent;
    z-index: 1;
    margin: 0;
}
#volumeSlider::-webkit-slider-runnable-track {
    height: 8px;
    border-radius: 4px;
    background: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color) var(--volume-fill, 50%), var(--volume-popup-bg) var(--volume-fill, 50%), var(--volume-popup-bg) 100%);
}
#volumeSlider::-moz-range-track {
    height: 8px;
    border-radius: 4px;
    background: linear-gradient(to right, var(--primary-color) 0%, var(--primary-color) var(--volume-fill, 50%), var(--volume-popup-bg) var(--volume-fill, 50%), var(--volume-popup-bg) 100%);
}
#volumeSlider::-ms-fill-lower {
    background: var(--primary-color);
}
#volumeSlider::-ms-fill-upper {
    background: var(--volume-popup-bg);
}
#volumeSlider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 18px;
    height: 18px;
    background: var(--primary-color, #007AFF);
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0,0,0,0.12);
    border: none;
    margin-top: -5px;
}
#volumeSlider:focus {
    outline: none;
}
#volumeSlider::-ms-thumb {
    width: 18px;
    height: 18px;
    background: var(--primary-color, #007AFF);
    border-radius: 50%;
    cursor: pointer;
    border: none;
}

/* ================= 评论面板 ================= */
.comments-panel {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 40%;
    background-color: var(--comment-bg);
    border-top: 1px solid var(--border-color);
    transform: translateY(100%);
    transition: transform var(--transition-speed);
    display: flex;
    flex-direction: column;
    z-index: 2000; /* 提高优先级，确保在功能栏之上 */
}

.comments-panel.active {
    transform: translateY(0);
}

.panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color);
    position: relative;
}

.comments-list {
    flex: 1;
    overflow-y: auto;
    padding: 15px 20px;
}

.comment {
    display: flex;
    gap: 12px;
    margin-bottom: 15px;
    background: transparent;
    border-radius: 8px;
    padding: 4px 0;
    align-items: flex-start;
}

.comment-avatar {
    width: 36px;
    height: 36px;
    background-color: var(--primary-color);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    flex-shrink: 0;
    overflow: hidden;
}

.comment-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.comment-content {
    flex: 1;
}

.comment-user {
    font-weight: bold;
    font-size: 18px;
    color: var(--text-color, #fff) !important;
    text-shadow: 0 2px 6px rgba(0,0,0,0.18);
    letter-spacing: 0.5px;
}

.comment-text {
    font-size: 17px;
    color: var(--text-color, #fff) !important;
    margin-bottom: 2px;
    text-shadow: 0 1px 4px rgba(0,0,0,0.12);
    font-weight: 500;
}

.comment-time {
    font-size: 13px;
    color: #bbb !important;
    margin-top: 2px;
    font-weight: normal;
}

.comment-like-btn {
    background: none;
    border: none;
    color: var(--text-color);
    opacity: 0.7;
    font-size: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 4px;
    transition: all var(--transition-speed);
}

.comment-like-btn:hover {
    opacity: 1;
}

.comment-like-btn.liked {
    color: var(--accent-color);
    opacity: 1;
}

.comment-like-btn i {
    font-size: 12px;
}

.empty-comments {
    text-align: center;
    padding: 20px;
    color: var(--text-color);
    opacity: 0.6;
}

.comment-input {
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: 10px;
}

.comment-input textarea {
    flex: 1;
    padding: 12px 15px;
    background-color: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 20px;
    color: var(--text-color);
    resize: none;
    outline: none;
    font-family: inherit;
    height: 45px;
    transition: height var(--transition-speed);
}

.comment-input textarea:focus {
    height: 80px;
}

#sendCommentBtn {
    padding: 0 20px;
    height: 45px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    transition: all var(--transition-speed);
}

#sendCommentBtn:hover {
    background-color: #3a56d4;
}

/* ================= iOS风格模态框 ================= */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.3);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-speed);
    backdrop-filter: var(--ios-blur);
    -webkit-backdrop-filter: var(--ios-blur);
}

.modal-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.modal-container {
    width: 90%;
    max-width: 400px;
    background: var(--nav-bg);
    backdrop-filter: var(--ios-blur);
    -webkit-backdrop-filter: var(--ios-blur);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--ios-shadow);
    border: var(--ios-border);
    transform: translateY(20px);
    transition: transform var(--transition-speed);
}

.modal-overlay.active .modal-container {
    transform: translateY(0);
}

.modal-header {
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.modal-header h2 {
    font-size: 20px;
}

.close-btn {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 20px;
    cursor: pointer;
    width: 36px;
    height: 36px;
    display: flex;
    justify-content: center;
    align-items: center;
    border-radius: 50%;
    transition: all var(--transition-speed);
}

.close-btn:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.form-group {
    margin-bottom: 15px;
    padding: 0 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 12px 15px;
    background-color: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    font-size: 15px;
    transition: border-color var(--transition-speed);
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.submit-btn {
    width: calc(100% - 40px);
    margin: 20px;
    padding: 12px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    cursor: pointer;
    transition: all var(--transition-speed);
}

.submit-btn:hover {
    background-color: #3a56d4;
}

.form-footer {
    padding: 15px 20px;
    text-align: center;
    border-top: 1px solid var(--border-color);
    font-size: 14px;
}

.form-footer a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-speed);
}

.form-footer a:hover {
    color: var(--accent-color);
}

/* ================= 个人中心面板 ================= */
.profile-panel {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 700px;
    max-width: 95vw;
    max-height: 95vh;
    overflow-y: auto;
    box-sizing: border-box;
    background-color: var(--profile-bg);
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    z-index: 1000;
    display: none;
    opacity: 0;
    transition: opacity var(--transition-speed);
    max-height: 90vh;
    overflow-y: auto;
    display: block;
}

.profile-panel.active {
    display: block;
    opacity: 1;
}

.profile-panel .panel-header {
    position: sticky;
    top: 0;
    background-color: var(--profile-bg);
    z-index: 10;
}

.profile-content {
    padding: 20px;
    max-height: 80vh;
    overflow-y: auto;
    padding-bottom: 60px; /* 增加底部留白，防止最后一行被裁剪 */
}

.profile-header {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
    position: relative;
}

.profile-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    margin-right: 20px;
    overflow: hidden;
    position: relative;
}

.profile-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.avatar-upload-btn {
    position: absolute;
    bottom: 0;
    right: 0;
    width: 28px;
    height: 28px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
}

.profile-info {
    flex: 1;
}

.profile-username-input {
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 22px;
    font-weight: bold;
    width: 100%;
    padding: 5px;
    border-radius: 4px;
    transition: all var(--transition-speed);
}

.profile-username-input:focus {
    outline: none;
    background-color: rgba(255, 255, 255, 0.1);
}

.profile-info p {
    font-size: 14px;
    color: var(--text-color);
    opacity: 0.7;
}

.profile-tabs {
    display: flex;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 15px;
}

.profile-tab {
    padding: 12px 24px;
    background: none;
    border: none;
    color: var(--text-color);
    opacity: 0.7;
    font-size: 16px;
    cursor: pointer;
    position: relative;
}

.profile-tab.active {
    opacity: 1;
    font-weight: bold;
}

.profile-tab.active::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary-color);
}

.profile-tab-content {
    height: auto !important;
    overflow: visible !important;
    padding-bottom: 92px !important; /* 保证最后一行完整显示且紧凑 */
}

.likes-grid, .history-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    padding: 5px;
    padding-bottom: 0 !important;
    margin-bottom: 0 !important;
    gap: 12px !important;
}

.history-grid {
    max-height: 500px;
    overflow-y: auto;
}

.video-grid-item {
    cursor: pointer;
    transition: transform var(--transition-speed);
    position: relative;
}

.video-grid-item:hover {
    transform: scale(1.03);
}

.video-thumbnail {
    width: 100%;
    aspect-ratio: 16/9;
    background-color: var(--darker-bg);
    background-size: cover;
    background-position: center;
    border-radius: 6px;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
}

.video-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.video-thumbnail i {
    position: absolute;
    color: white;
    font-size: 24px;
    opacity: 0.8;
    z-index: 1;
}

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--text-color);
    opacity: 0.6;
    grid-column: 1 / -1;
}

.empty-state i {
    font-size: 36px;
    margin-bottom: 15px;
    display: block;
}

.empty-state p {
    font-size: 16px;
}

/* ================= 响应式设计 ================= */
@media (max-width: 768px) {
    :root {
        --control-size: 60px;
        --progress-ring-size: 68px;
        --nav-width: 240px;
    }
    
    .side-nav {
        position: fixed;
        left: -100%;
        top: 0;
        z-index: 200;
        transition: left var(--transition-speed);
    }
    
    .side-nav.active {
        left: 0;
    }
    
    .control-panel {
        flex-direction: row;
        right: 50%;
        top: auto;
        bottom: 30px;
        transform: translateX(50%);
        gap: 15px;
        align-items: flex-end;
    }
    
    .volume-popup {
        right: 50%;
        left: auto;
        top: -70px;
        transform: translateX(50%);
    }
    
    .control-btn {
        width: var(--control-size);
        height: var(--control-size);
    }
    
    .progress-ring-container {
        width: var(--progress-ring-size);
        height: var(--progress-ring-size);
    }
    
    .comments-panel {
        height: 60%;
    }

    .profile-panel {
        width: 95%;
        max-height: 90vh;
    }

    .profile-content {
        max-height: calc(90vh - 60px);
    }
    
    .likes-grid, .history-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .likes-grid, .history-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 900px) {
    .control-panel {
        right: 8px;
        gap: 20px;
    }
    .control-btn {
        width: 56px;
        height: 56px;
    }
}
@media (max-width: 600px) {
    .control-panel {
        right: 2px;
        gap: 12px;
    }
    .control-btn {
        width: 44px;
        height: 44px;
    }
}

/* 辅助类 */
.hidden {
    display: none !important;
}

.side-nav, .comments-panel, .user-panel, .profile-panel {
    background: rgba(255,255,255,0.10) !important;
    backdrop-filter: blur(10px) !important;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08) !important;
}

/* 白天模式下侧边栏更浅 */
body.light-mode .side-nav,
body.light-mode .side-panel {
    background: rgba(255,255,255,0.85) !important;
    color: #222 !important;
    box-shadow: 0 2px 8px rgba(0,0,0,0.06) !important;
}

/* 夜间模式下侧边栏更暗 */
body.dark-mode .side-nav,
body.dark-mode .side-panel {
    background: rgba(30,34,44,0.92) !important;
    color: #fff !important;
    box-shadow: 0 2px 8px rgba(0,0,0,0.18) !important;
}

/* 伸缩栏收起宽度优化 */
.side-nav.collapsed {
    width: 64px !important;
    min-width: 64px !important;
    max-width: 64px !important;
    overflow: visible !important;
}
.side-nav.collapsed .nav-text,
.side-nav.collapsed .nav-title {
    display: none !important;
}
.side-nav.collapsed .nav-icon,
.side-nav.collapsed .avatar,
.side-nav.collapsed .collapse-nav-btn {
    display: flex !important;
    justify-content: center;
    align-items: center;
}

.control-panel, .video-controls, .main-content, .video-container {
    overflow: visible !important;
}
.volume-popup {
    z-index: 9999 !important;
}
.comments-panel .close-btn {
    z-index: 9999;
    position: absolute;
    right: 20px;
    top: 15px;
    background: rgba(0,0,0,0.12);
    color: var(--text-color);
    font-size: 22px;
    border-radius: 50%;
    box-shadow: 0 2px 8px rgba(0,0,0,0.10);
}
.comments-panel .close-btn:hover {
    background: var(--primary-color);
    color: #fff;
}
.comments-list, .comment-user, .comment-text, .comment-time, .comment-like-btn {
    color: var(--text-color) !important;
    font-size: 16px;
    word-break: break-all;
}
body.light-mode .comment-user, body.light-mode .comment-text, body.light-mode .comments-list {
    color: #222 !important;
}
body.dark-mode .comment-user, body.dark-mode .comment-text, body.dark-mode .comments-list {
    color: #fff !important;
}
.profile-panel {
    overflow: hidden !important;
}
.profile-content {
    max-height: 80vh;
    overflow-y: auto;
}
.profile-tab-content {
    overflow: visible;
    max-height: none;
}

/* 个人中心内容区优化 */
.profile-panel {
    display: flex;
    flex-direction: column;
    height: 90vh;
    max-width: 95vw;
    /* 不要 overflow-y: auto; 不要 max-height */
}

.profile-tab-content {
    flex: 1 1 auto;
    overflow-y: auto;
    padding-bottom: 0 !important;
}

#likesGrid, .likesGrid, #historyGrid, .historyGrid {
    padding-bottom: 0 !important;
    margin-bottom: 0 !important;
    gap: 12px !important; /* 行间距 */
}

.video-grid-item {
    background: #222;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    cursor: pointer;
    transition: transform 0.15s;
}
.video-grid-item:hover {
    transform: translateY(-4px) scale(1.03);
    box-shadow: 0 4px 16px rgba(0,0,0,0.15);
}
.video-thumbnail {
    width: 100%;
    aspect-ratio: 16/9;
    background: #111 center center/cover no-repeat;
    display: flex;
    align-items: center;
    justify-content: center;
}
.video-thumbnail i {
    font-size: 2.2em;
    color: #fff;
    opacity: 0.8;
}

#loginModal, .login-modal {
    z-index: 9999 !important;
    position: fixed !important;
    pointer-events: auto !important;
    display: flex;
    align-items: center;
    justify-content: center;
    left: 0;
    top: 0;
    width: 100vw;
    height: 100vh;
}

/* 遮罩层z-index应低于弹窗（如有） */
.modal-backdrop, .mask, .overlay {
    z-index: 9998 !important;
}

/* 遮罩层和弹窗默认隐藏 */
.modal-overlay,
.modal-backdrop,
.mask,
.overlay,
#loginModal,
.login-modal {
    display: none;
    pointer-events: none;
}

/* 只有active时才显示并可交互 */
.modal-overlay.active,
.modal-backdrop.active,
.mask.active,
.overlay.active,
#loginModal.active,
.login-modal.active {
    display: flex !important;
    pointer-events: auto !important;
    z-index: 9999 !important;
}

/* 其它内容区（如 .profile-panel）z-index 1000，防止被遮挡 */
.profile-panel {
    z-index: 1000 !important;
}

/* 频道按钮内部进度条动画样式 */
.source-content {
  position: relative;
}
.switch-progress-bar {
  position: absolute;
  left: 12px; right: 12px; bottom: 6px;
  height: 4px;
  width: 0;
  background: linear-gradient(90deg,#4361ee,#4f8cff);
  border-radius: 2px;
  box-shadow: 0 1px 4px #4361ee33;
  transition: width 0.6s cubic-bezier(.4,0,.2,1), opacity 0.3s;
  opacity: 0;
  pointer-events: none;
  z-index: 2;
}
.source-item.switching .switch-progress-bar {
  opacity: 1;
}

/* 抖音风格 loading 动画样式 */
.loading-spinner-outer {
  position: relative;
  width: 64px;
  height: 64px;
  margin: 0 auto 12px auto;
}
.loading-spinner {
  transform: rotate(-90deg);
}
.loading-bg {
  stroke: #222c;
}
.loading-fg {
  stroke: url(#loading-gradient);
  stroke-dasharray: 176;
  stroke-dashoffset: 44;
  transition: stroke-dashoffset 0.2s;
  stroke-linecap: round;
  animation: loading-rotate 1s linear infinite;
}
@keyframes loading-rotate {
  100% { transform: rotate(360deg);}
}
.loading-text {
  text-align: center;
  font-size: 16px;
  color: #fff;
  margin-top: 8px;
  letter-spacing: 1px;
}

/* 抖音双圆点弹跳 loading 动画 */
.dy-loading-dots {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  margin-bottom: 8px;
}
.dy-dot {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  margin: 0 6px;
  animation: dy-bounce 0.6s infinite alternate;
}
.dy-dot-left {
  background: #00f2ea;
  animation-delay: 0s;
}
.dy-dot-right {
  background: #ff0050;
  animation-delay: 0.3s;
}
@keyframes dy-bounce {
  0% { transform: translateY(0); }
  100% { transform: translateY(-18px); }
}
.loading-text {
  text-align: center;
  font-size: 16px;
  color: #fff;
  margin-top: 8px;
  letter-spacing: 1px;
}

/* 评论发送按钮动画，仿点赞按钮 */
.comment-send-btn {
  position: relative;
  width: 48px;
  height: 48px;
  border: 2px solid #fff;
  border-radius: 50%;
  background: none;
  color: #fff;
  font-size: 22px;
  cursor: pointer;
  transition: background 0.3s, border-color 0.3s;
  overflow: hidden;
  outline: none;
  display: flex;
  align-items: center;
  justify-content: center;
}
.comment-send-btn.loading {
  border-color: #ccc;
  color: #ccc;
  background: none;
  cursor: not-allowed;
}
.comment-send-btn.ready {
  border-color: #fff;
  color: #fff;
  background: none;
  cursor: pointer;
}
.comment-send-btn.filled {
  background: #f72585;
  border-color: #f72585;
  color: #fff;
  transition: background 0.3s, border-color 0.3s;
}
.comment-send-btn .send-icon {
  transition: color 0.3s;
}
.comment-send-btn.loading .send-icon {
  color: #ccc;
}
.comment-send-btn.filled .send-icon {
  color: #fff;
}
.comment-send-btn.animating {
  animation: sendBtnPop 0.3s;
}
@keyframes sendBtnPop {
  0% { transform: scale(1); }
  30% { transform: scale(1.18); }
  60% { transform: scale(0.92); }
  100% { transform: scale(1); }
}

#likeBtn .heart-svg {
  transition: transform 0.4s cubic-bezier(.4,1.6,.6,1);
}
#likeBtn.liked .heart-svg {
  animation: heartLikePop 0.4s cubic-bezier(.4,1.6,.6,1);
}
@keyframes heartLikePop {
  0% { transform: scale(1); }
  40% { transform: scale(1.35); }
  70% { transform: scale(0.92); }
  100% { transform: scale(1); }
}
#likeBtn .heart-fill {
  stroke: #fff;
  stroke-width: 2;
  transition: fill 0.5s cubic-bezier(.4,1.6,.6,1);
}
#likeBtn.filling .heart-fill {
  fill: #fff;
}
#likeBtn.liked .heart-fill {
  fill: #f72585;
  stroke: #f72585;
}
#likeBtn .heart-outline {
  stroke: #fff;
  stroke-width: 2;
  fill: none;
  filter: drop-shadow(0 2px 6px rgba(0,0,0,0.12));
  transition: stroke 0.3s;
}
#likeBtn.liked .heart-outline {
  stroke: #f72585;
}
@keyframes heartFillPop {
  0% { fill: none; }
  50% { fill: #fff; }
  100% { fill: #f72585; }
}
.heart-fill.heart-animating {
  animation: heartFillPop 0.5s cubic-bezier(.4,1.6,.6,1) forwards !important;
  fill: none !important;
}