:root {
            /* 亮色主题 */
            --bg-primary: #f0f2f7;
            --bg-secondary: #ffffff;
            --bg-tertiary: #f8f9fc;
            --bg-sidebar: rgba(255, 255, 255, 0.75);
            --bg-chat: #f5f6fa;
            --bg-input: #ffffff;
            --bg-bubble-self: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            --bg-bubble-other: #ffffff;
            --bg-bubble-other-hover: #f8f9fc;
            --bg-hover: #f0f2f8;
            --bg-active: #eef0ff;
            --bg-unread: #ff4757;
            --text-primary: #1a1d2e;
            --text-secondary: #6b7280;
            --text-tertiary: #9ca3af;
            --text-bubble-self: #ffffff;
            --text-bubble-other: #1a1d2e;
            --border-color: rgba(0, 0, 0, 0.06);
            --border-light: rgba(0, 0, 0, 0.04);
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.06);
            --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.06), 0 2px 6px rgba(0, 0, 0, 0.04);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08), 0 4px 12px rgba(0, 0, 0, 0.04);
            --shadow-bubble: 0 2px 8px rgba(102, 126, 234, 0.18), 0 1px 3px rgba(118, 75, 162, 0.12);
            --shadow-input: 0 2px 12px rgba(0, 0, 0, 0.06), 0 0 0 1px rgba(0, 0, 0, 0.04);
            --glass-bg: rgba(255, 255, 255, 0.7);
            --glass-border: rgba(255, 255, 255, 0.5);
            --glass-blur: blur(20px);
            --accent-1: #667eea;
            --accent-2: #764ba2;
            --accent-glow: rgba(102, 126, 234, 0.3);
            --online-color: #22c55e;
            --online-glow: rgba(34, 197, 94, 0.4);
            --typing-color: #f59e0b;
            --scrollbar-thumb: #d1d5db;
            --scrollbar-track: transparent;
            --overlay: rgba(0, 0, 0, 0.3);
            --danger: #ef4444;
            --badge-bg: #ff4757;
            --badge-text: #ffffff;
            --pinned-bg: #fefce8;
            --divider: #e5e7eb;
        }

        [data-theme="dark"] {
            --bg-primary: #0f1119;
            --bg-secondary: #1a1d2e;
            --bg-tertiary: #1e2135;
            --bg-sidebar: rgba(26, 29, 46, 0.8);
            --bg-chat: #151823;
            --bg-input: #1e2135;
            --bg-bubble-self: linear-gradient(135deg, #667eea 0%, #8b5cf6 100%);
            --bg-bubble-other: #252840;
            --bg-bubble-other-hover: #2a2d45;
            --bg-hover: #252840;
            --bg-active: #2a2d48;
            --bg-unread: #ff4757;
            --text-primary: #e8eaed;
            --text-secondary: #a0a5b8;
            --text-tertiary: #6b7084;
            --text-bubble-self: #ffffff;
            --text-bubble-other: #e0e2ea;
            --border-color: rgba(255, 255, 255, 0.06);
            --border-light: rgba(255, 255, 255, 0.04);
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2), 0 1px 2px rgba(0, 0, 0, 0.3);
            --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3), 0 2px 6px rgba(0, 0, 0, 0.2);
            --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.4), 0 4px 12px rgba(0, 0, 0, 0.3);
            --shadow-bubble: 0 2px 10px rgba(102, 126, 234, 0.25), 0 1px 4px rgba(139, 92, 246, 0.2);
            --shadow-input: 0 2px 12px rgba(0, 0, 0, 0.3), 0 0 0 1px rgba(255, 255, 255, 0.06);
            --glass-bg: rgba(26, 29, 46, 0.75);
            --glass-border: rgba(255, 255, 255, 0.08);
            --glass-blur: blur(20px);
            --accent-1: #7c8cf8;
            --accent-2: #9b6dff;
            --accent-glow: rgba(124, 140, 248, 0.25);
            --online-color: #22c55e;
            --online-glow: rgba(34, 197, 94, 0.35);
            --typing-color: #fbbf24;
            --scrollbar-thumb: #3a3d52;
            --scrollbar-track: transparent;
            --overlay: rgba(0, 0, 0, 0.6);
            --danger: #f87171;
            --badge-bg: #ff4757;
            --badge-text: #ffffff;
            --pinned-bg: #1e2130;
            --divider: #2a2d40;
        }

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

        body {
            font-family: 'Segoe UI', 'Inter', -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
            background: var(--bg-primary);
            color: var(--text-primary);
            height: 100vh;
            width: 100vw;
            overflow: hidden;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: background 0.4s ease, color 0.4s ease;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            position: relative;
        }

        /* 背景光晕装饰 */
        body::before {
            content: '';
            position: fixed;
            top: -30%;
            right: -20%;
            width: 70vw;
            height: 70vw;
            background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
            pointer-events: none;
            z-index: 0;
            animation: bgGlowFloat 15s ease-in-out infinite;
            opacity: 0.5;
        }
        body::after {
            content: '';
            position: fixed;
            bottom: -25%;
            left: -15%;
            width: 60vw;
            height: 60vw;
            background: radial-gradient(circle, rgba(118, 75, 162, 0.2) 0%, transparent 70%);
            pointer-events: none;
            z-index: 0;
            animation: bgGlowFloat 18s ease-in-out infinite reverse;
            opacity: 0.4;
        }

        @keyframes bgGlowFloat {
            0%,
            100% {
                transform: translate(0, 0) scale(1);
            }
            25% {
                transform: translate(3%, -3%) scale(1.05);
            }
            50% {
                transform: translate(-2%, 2%) scale(0.95);
            }
            75% {
                transform: translate(-3%, -1%) scale(1.03);
            }
        }

        /* 主容器 */
        .chat-app {
            position: relative;
            z-index: 1;
            width: min(100vw, 1300px);
            height: min(100vh, 880px);
            display: flex;
            border-radius: 24px;
            overflow: hidden;
            box-shadow: var(--shadow-lg);
            background: var(--bg-secondary);
            transition: all 0.4s ease;
            margin: 16px;
        }

        @media (max-width: 768px) {
            .chat-app {
                border-radius: 0;
                margin: 0;
                width: 100vw;
                height: 100vh;
                max-height: 100vh;
            }
        }

        /* ========== 侧边栏 ========== */
        .sidebar {
            width: 380px;
            min-width: 380px;
            background: var(--glass-bg);
            backdrop-filter: var(--glass-blur);
            -webkit-backdrop-filter: var(--glass-blur);
            border-right: 1px solid var(--border-color);
            display: flex;
            flex-direction: column;
            transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
            position: relative;
            z-index: 2;
        }

        @media (max-width: 768px) {
            .sidebar {
                width: 100%;
                min-width: 100%;
                position: absolute;
                inset: 0;
                z-index: 10;
                border-radius: 0;
            }
            .sidebar.hidden-on-mobile {
                transform: translateX(-100%);
                opacity: 0;
                pointer-events: none;
            }
        }

        /* 侧边栏头部 */
        .sidebar-header {
            padding: 20px 20px 12px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 12px;
            flex-shrink: 0;
        }
        .sidebar-header .user-info {
            display: flex;
            align-items: center;
            gap: 12px;
            flex: 1;
            min-width: 0;
        }
        .avatar-wrapper {
            position: relative;
            flex-shrink: 0;
        }
        .avatar {
            width: 44px;
            height: 44px;
            border-radius: 14px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 16px;
            color: #fff;
            letter-spacing: 0.5px;
            box-shadow: var(--shadow-sm);
            transition: transform 0.2s ease, box-shadow 0.2s ease;
            cursor: pointer;
            user-select: none;
        }
        .avatar:hover {
            transform: scale(1.05);
            box-shadow: var(--shadow-md);
        }
        .avatar.avatar-sm {
            width: 40px;
            height: 40px;
            border-radius: 12px;
            font-size: 14px;
        }
        .avatar.avatar-lg {
            width: 52px;
            height: 52px;
            border-radius: 16px;
            font-size: 18px;
        }
        .online-dot {
            position: absolute;
            bottom: -1px;
            right: -1px;
            width: 13px;
            height: 13px;
            background: var(--online-color);
            border-radius: 50%;
            border: 2.5px solid var(--bg-secondary);
            box-shadow: 0 0 0 3px var(--online-glow);
            animation: onlinePulse 2s ease-in-out infinite;
        }
        @keyframes onlinePulse {
            0%,
            100% {
                box-shadow: 0 0 0 3px var(--online-glow);
            }
            50% {
                box-shadow: 0 0 0 8px transparent;
            }
        }
        .user-details {
            display: flex;
            flex-direction: column;
            min-width: 0;
        }
        .user-name {
            font-weight: 700;
            font-size: 15px;
            color: var(--text-primary);
            line-height: 1.2;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }
        .user-status {
            font-size: 12px;
            color: var(--online-color);
            font-weight: 500;
            letter-spacing: 0.3px;
        }
        .header-actions {
            display: flex;
            gap: 4px;
            flex-shrink: 0;
        }
        .icon-btn {
            width: 38px;
            height: 38px;
            border-radius: 12px;
            border: none;
            background: transparent;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-secondary);
            transition: all 0.2s ease;
            position: relative;
        }
        .icon-btn:hover {
            background: var(--bg-hover);
            color: var(--text-primary);
        }
        .icon-btn:active {
            transform: scale(0.93);
            transition: transform 0.1s ease;
        }
        .icon-btn svg {
            width: 20px;
            height: 20px;
        }
        .theme-toggle {
            position: relative;
        }
        .theme-toggle .sun-icon,
        .theme-toggle .moon-icon {
            transition: all 0.35s ease;
            position: absolute;
        }
        [data-theme="dark"] .sun-icon {
            opacity: 0;
            transform: rotate(180deg) scale(0.5);
        }
        [data-theme="dark"] .moon-icon {
            opacity: 1;
            transform: rotate(0deg) scale(1);
        }
        .sun-icon {
            opacity: 1;
            transform: rotate(0deg) scale(1);
        }
        .moon-icon {
            opacity: 0;
            transform: rotate(-180deg) scale(0.5);
        }

        /* 搜索栏 */
        .search-wrapper {
            padding: 8px 20px 16px;
            flex-shrink: 0;
        }
        .search-bar {
            display: flex;
            align-items: center;
            gap: 10px;
            background: var(--bg-tertiary);
            border-radius: 14px;
            padding: 10px 16px;
            border: 1.5px solid var(--border-light);
            transition: all 0.3s ease;
            cursor: text;
        }
        .search-bar:focus-within {
            border-color: var(--accent-1);
            box-shadow: 0 0 0 4px var(--accent-glow);
            background: var(--bg-secondary);
        }
        .search-bar svg {
            width: 18px;
            height: 18px;
            color: var(--text-tertiary);
            flex-shrink: 0;
            transition: color 0.3s ease;
        }
        .search-bar:focus-within svg {
            color: var(--accent-1);
        }
        .search-bar input {
            flex: 1;
            border: none;
            outline: none;
            background: transparent;
            font-size: 14px;
            color: var(--text-primary);
            font-family: inherit;
        }
        .search-bar input::placeholder {
            color: var(--text-tertiary);
        }

        /* 标签筛选 */
        .filter-tabs {
            display: flex;
            gap: 6px;
            padding: 0 20px 12px;
            flex-shrink: 0;
            overflow-x: auto;
            scrollbar-width: none;
        }
        .filter-tabs::-webkit-scrollbar {
            display: none;
        }
        .filter-tab {
            padding: 7px 15px;
            border-radius: 20px;
            font-size: 12.5px;
            font-weight: 600;
            cursor: pointer;
            border: 1.5px solid var(--border-color);
            background: var(--bg-tertiary);
            color: var(--text-secondary);
            white-space: nowrap;
            transition: all 0.25s ease;
            letter-spacing: 0.2px;
            user-select: none;
        }
        .filter-tab:hover {
            background: var(--bg-hover);
            border-color: var(--accent-1);
            color: var(--accent-1);
        }
        .filter-tab.active {
            background: var(--accent-1);
            color: #fff;
            border-color: var(--accent-1);
            box-shadow: 0 2px 8px var(--accent-glow);
        }

        /* 联系人列表 */
        .contacts-list {
            flex: 1;
            overflow-y: auto;
            overflow-x: hidden;
            padding: 4px 12px 8px;
            scroll-behavior: smooth;
        }
        .contacts-list::-webkit-scrollbar {
            width: 4px;
        }
        .contacts-list::-webkit-scrollbar-track {
            background: var(--scrollbar-track);
            border-radius: 10px;
        }
        .contacts-list::-webkit-scrollbar-thumb {
            background: var(--scrollbar-thumb);
            border-radius: 10px;
        }
        .contacts-list::-webkit-scrollbar-thumb:hover {
            background: var(--text-tertiary);
        }

        /* 分组标签 */
        .section-label {
            font-size: 11px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 1.2px;
            color: var(--text-tertiary);
            padding: 10px 12px 6px;
            margin-top: 2px;
            user-select: none;
        }

        /* 联系人卡片 */
        .contact-card {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 11px 12px;
            border-radius: 16px;
            cursor: pointer;
            transition: all 0.2s ease;
            position: relative;
            margin-bottom: 2px;
            border: 1.5px solid transparent;
            user-select: none;
            animation: fadeInUp 0.4s ease forwards;
            opacity: 0;
        }
        @keyframes fadeInUp {
            from {
                opacity: 0;
                transform: translateY(8px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }
        .contact-card:nth-child(1) {
            animation-delay: 0.02s;
        }
        .contact-card:nth-child(2) {
            animation-delay: 0.06s;
        }
        .contact-card:nth-child(3) {
            animation-delay: 0.10s;
        }
        .contact-card:nth-child(4) {
            animation-delay: 0.14s;
        }
        .contact-card:nth-child(5) {
            animation-delay: 0.18s;
        }
        .contact-card:nth-child(6) {
            animation-delay: 0.22s;
        }
        .contact-card:nth-child(7) {
            animation-delay: 0.26s;
        }
        .contact-card:nth-child(8) {
            animation-delay: 0.30s;
        }
        .contact-card:hover {
            background: var(--bg-hover);
            transform: translateX(2px);
        }
        .contact-card:active {
            transform: scale(0.97);
            transition: transform 0.1s ease;
        }
        .contact-card.active {
            background: var(--bg-active);
            border-color: var(--accent-1);
            box-shadow: 0 2px 10px var(--accent-glow);
        }
        .contact-card.pinned {
            background: var(--pinned-bg);
        }
        .contact-card .contact-avatar-wrap {
            position: relative;
            flex-shrink: 0;
        }
        .contact-card .contact-info {
            flex: 1;
            min-width: 0;
            display: flex;
            flex-direction: column;
            gap: 3px;
        }
        .contact-card .contact-name-row {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 8px;
        }
        .contact-card .contact-name {
            font-weight: 600;
            font-size: 14px;
            color: var(--text-primary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            letter-spacing: 0.1px;
        }
        .contact-card .contact-time {
            font-size: 11px;
            color: var(--text-tertiary);
            flex-shrink: 0;
            font-weight: 500;
        }
        .contact-card .contact-preview {
            display: flex;
            align-items: center;
            gap: 6px;
            font-size: 12.8px;
            color: var(--text-secondary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }
        .contact-card .typing-indicator-mini {
            display: flex;
            gap: 3px;
            align-items: center;
        }
        .contact-card .typing-indicator-mini span {
            width: 5px;
            height: 5px;
            border-radius: 50%;
            background: var(--typing-color);
            animation: typingMiniBounce 1.2s ease-in-out infinite;
        }
        .contact-card .typing-indicator-mini span:nth-child(2) {
            animation-delay: 0.15s;
        }
        .contact-card .typing-indicator-mini span:nth-child(3) {
            animation-delay: 0.3s;
        }
        @keyframes typingMiniBounce {
            0%,
            60%,
            100% {
                transform: translateY(0);
                opacity: 0.5;
            }
            30% {
                transform: translateY(-6px);
                opacity: 1;
            }
        }
        .unread-badge {
            background: var(--badge-bg);
            color: var(--badge-text);
            font-size: 10.5px;
            font-weight: 700;
            padding: 2.5px 7px;
            border-radius: 10px;
            min-width: 20px;
            text-align: center;
            flex-shrink: 0;
            letter-spacing: 0.3px;
            animation: badgePop 0.3s ease;
        }
        @keyframes badgePop {
            0% {
                transform: scale(0);
            }
            60% {
                transform: scale(1.2);
            }
            100% {
                transform: scale(1);
            }
        }
        .pin-icon-mini {
            width: 12px;
            height: 12px;
            color: var(--typing-color);
            flex-shrink: 0;
        }
        .group-badge {
            font-size: 10px;
            background: var(--bg-tertiary);
            color: var(--text-secondary);
            padding: 1.5px 6px;
            border-radius: 8px;
            font-weight: 500;
            letter-spacing: 0.3px;
        }

        /* ========== 主聊天区域 ========== */
        .chat-main {
            flex: 1;
            display: flex;
            flex-direction: column;
            background: var(--bg-chat);
            position: relative;
            min-width: 0;
            transition: background 0.4s ease;
        }
        @media (max-width: 768px) {
            .chat-main {
                position: absolute;
                inset: 0;
                z-index: 5;
            }
            .chat-main.hidden-on-mobile {
                z-index: 1;
            }
        }

        /* 聊天头部 */
        .chat-header {
            padding: 14px 20px;
            display: flex;
            align-items: center;
            gap: 12px;
            background: var(--glass-bg);
            backdrop-filter: var(--glass-blur);
            -webkit-backdrop-filter: var(--glass-blur);
            border-bottom: 1px solid var(--border-color);
            flex-shrink: 0;
            z-index: 3;
            transition: all 0.3s ease;
        }
        .chat-header .back-btn {
            display: none;
            width: 36px;
            height: 36px;
            border-radius: 10px;
            border: none;
            background: var(--bg-hover);
            cursor: pointer;
            align-items: center;
            justify-content: center;
            color: var(--text-primary);
            flex-shrink: 0;
            transition: all 0.2s ease;
        }
        .chat-header .back-btn:hover {
            background: var(--bg-active);
        }
        .chat-header .back-btn svg {
            width: 20px;
            height: 20px;
        }
        @media (max-width: 768px) {
            .chat-header .back-btn {
                display: flex;
            }
        }
        .chat-header .chat-header-info {
            flex: 1;
            min-width: 0;
            cursor: pointer;
        }
        .chat-header .chat-header-name {
            font-weight: 700;
            font-size: 15px;
            color: var(--text-primary);
            letter-spacing: 0.1px;
        }
        .chat-header .chat-header-status {
            font-size: 12px;
            color: var(--text-tertiary);
            font-weight: 500;
        }
        .chat-header .chat-header-status.online {
            color: var(--online-color);
        }
        .chat-header .header-actions-right {
            display: flex;
            gap: 2px;
            flex-shrink: 0;
        }

        /* 消息区域 */
        .messages-area {
            flex: 1;
            overflow-y: auto;
            overflow-x: hidden;
            padding: 16px 20px;
            display: flex;
            flex-direction: column;
            gap: 3px;
            scroll-behavior: smooth;
            position: relative;
        }
        .messages-area::-webkit-scrollbar {
            width: 4px;
        }
        .messages-area::-webkit-scrollbar-track {
            background: var(--scrollbar-track);
            border-radius: 10px;
        }
        .messages-area::-webkit-scrollbar-thumb {
            background: var(--scrollbar-thumb);
            border-radius: 10px;
        }
        .messages-area::-webkit-scrollbar-thumb:hover {
            background: var(--text-tertiary);
        }

        /* 日期分隔线 */
        .date-divider {
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 12px 0 16px;
            user-select: none;
        }
        .date-divider span {
            font-size: 11px;
            font-weight: 600;
            color: var(--text-tertiary);
            background: var(--bg-chat);
            padding: 5px 14px;
            border-radius: 12px;
            border: 1px solid var(--border-color);
            letter-spacing: 0.3px;
            text-transform: uppercase;
        }

        /* 消息气泡 */
        .message-wrapper {
            display: flex;
            flex-direction: column;
            max-width: 70%;
            animation: msgSlideIn 0.35s cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
            opacity: 0;
        }
        @keyframes msgSlideIn {
            from {
                opacity: 0;
                transform: translateY(12px) scale(0.96);
            }
            to {
                opacity: 1;
                transform: translateY(0) scale(1);
            }
        }
        .message-wrapper.sent {
            align-self: flex-end;
            align-items: flex-end;
        }
        .message-wrapper.received {
            align-self: flex-start;
            align-items: flex-start;
        }
        .message-bubble {
            padding: 10px 15px;
            border-radius: 18px;
            font-size: 14px;
            line-height: 1.5;
            word-break: break-word;
            position: relative;
            transition: all 0.2s ease;
            letter-spacing: 0.15px;
        }
        .message-wrapper.sent .message-bubble {
            background: var(--bg-bubble-self);
            color: var(--text-bubble-self);
            border-bottom-right-radius: 6px;
            box-shadow: var(--shadow-bubble);
        }
        .message-wrapper.received .message-bubble {
            background: var(--bg-bubble-other);
            color: var(--text-bubble-other);
            border-bottom-left-radius: 6px;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--border-light);
        }
        .message-wrapper.received .message-bubble:hover {
            background: var(--bg-bubble-other-hover);
        }
        .message-time {
            font-size: 10.5px;
            color: var(--text-tertiary);
            margin-top: 4px;
            padding: 0 4px;
            font-weight: 500;
            letter-spacing: 0.2px;
            user-select: none;
        }
        .message-wrapper.sent .message-time {
            text-align: right;
        }
        /* 连续消息间距优化 */
        .message-wrapper+.message-wrapper {
            margin-top: 2px;
        }
        .message-wrapper.sent+.message-wrapper.sent .message-bubble {
            border-bottom-right-radius: 18px;
        }
        .message-wrapper.received+.message-wrapper.received .message-bubble {
            border-bottom-left-radius: 18px;
        }
        .message-wrapper.sent+.message-wrapper.received,
        .message-wrapper.received+.message-wrapper.sent {
            margin-top: 10px;
        }

        /* 消息悬停效果 */
        .message-bubble:hover {
            transform: translateY(-1px);
        }
        .message-wrapper.sent .message-bubble:hover {
            box-shadow: 0 6px 20px rgba(102, 126, 234, 0.35), 0 2px 6px rgba(118, 75, 162, 0.25);
        }

        /* 打字指示器 */
        .typing-bubble {
            display: flex;
            gap: 4px;
            padding: 12px 16px;
            background: var(--bg-bubble-other);
            border-radius: 18px;
            border-bottom-left-radius: 6px;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-sm);
            align-self: flex-start;
            animation: msgSlideIn 0.3s ease forwards;
        }
        .typing-bubble span {
            width: 7px;
            height: 7px;
            border-radius: 50%;
            background: var(--text-tertiary);
            animation: typingDotBounce 1.3s ease-in-out infinite;
        }
        .typing-bubble span:nth-child(2) {
            animation-delay: 0.2s;
        }
        .typing-bubble span:nth-child(3) {
            animation-delay: 0.4s;
        }
        @keyframes typingDotBounce {
            0%,
            60%,
            100% {
                transform: translateY(0);
                opacity: 0.4;
            }
            30% {
                transform: translateY(-8px);
                opacity: 1;
            }
        }

        /* 输入区域 */
        .input-area {
            padding: 12px 16px 16px;
            flex-shrink: 0;
            display: flex;
            align-items: flex-end;
            gap: 10px;
            background: var(--glass-bg);
            backdrop-filter: var(--glass-blur);
            -webkit-backdrop-filter: var(--glass-blur);
            border-top: 1px solid var(--border-color);
            transition: all 0.3s ease;
            z-index: 3;
        }
        .input-area .attach-btn {
            width: 40px;
            height: 40px;
            border-radius: 13px;
            border: none;
            background: var(--bg-tertiary);
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--text-secondary);
            flex-shrink: 0;
            transition: all 0.2s ease;
        }
        .input-area .attach-btn:hover {
            background: var(--bg-hover);
            color: var(--accent-1);
            transform: rotate(15deg);
        }
        .input-area .attach-btn svg {
            width: 20px;
            height: 20px;
        }
        .input-wrapper {
            flex: 1;
            position: relative;
            display: flex;
            align-items: flex-end;
            background: var(--bg-input);
            border-radius: 20px;
            border: 1.5px solid var(--border-light);
            transition: all 0.3s ease;
            box-shadow: var(--shadow-sm);
            overflow: hidden;
        }
        .input-wrapper:focus-within {
            border-color: var(--accent-1);
            box-shadow: var(--shadow-input), 0 0 0 4px var(--accent-glow);
            border-radius: 20px;
        }
        .input-wrapper textarea {
            flex: 1;
            border: none;
            outline: none;
            background: transparent;
            padding: 10px 14px;
            font-size: 14px;
            color: var(--text-primary);
            font-family: inherit;
            resize: none;
            min-height: 42px;
            max-height: 120px;
            line-height: 1.5;
            letter-spacing: 0.15px;
        }
        .input-wrapper textarea::placeholder {
            color: var(--text-tertiary);
        }
        .emoji-btn {
            width: 36px;
            height: 36px;
            border-radius: 10px;
            border: none;
            background: transparent;
            cursor: pointer;
            color: var(--text-secondary);
            flex-shrink: 0;
            transition: all 0.2s ease;
            margin: 3px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 18px;
        }
        .emoji-btn:hover {
            background: var(--bg-hover);
            transform: scale(1.1);
        }
        .send-btn {
            width: 44px;
            height: 44px;
            border-radius: 14px;
            border: none;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            cursor: pointer;
            color: #fff;
            flex-shrink: 0;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: all 0.25s ease;
            box-shadow: 0 4px 14px rgba(102, 126, 234, 0.35);
            position: relative;
            overflow: hidden;
        }
        .send-btn:hover {
            transform: scale(1.06);
            box-shadow: 0 6px 22px rgba(102, 126, 234, 0.5);
        }
        .send-btn:active {
            transform: scale(0.9);
            transition: transform 0.1s ease;
        }
        .send-btn svg {
            width: 20px;
            height: 20px;
            position: relative;
            z-index: 1;
            transition: transform 0.3s ease;
        }
        .send-btn:hover svg {
            transform: translateX(2px);
        }
        .send-btn::after {
            content: '';
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, #764ba2 0%, #667eea 100%);
            opacity: 0;
            transition: opacity 0.3s ease;
            border-radius: 14px;
        }
        .send-btn:hover::after {
            opacity: 1;
        }

        /* 欢迎状态（无消息时） */
        .empty-state {
            flex: 1;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 16px;
            color: var(--text-tertiary);
            text-align: center;
            padding: 40px;
            user-select: none;
        }
        .empty-state .empty-icon {
            width: 80px;
            height: 80px;
            border-radius: 24px;
            background: var(--bg-tertiary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 36px;
            animation: floatIcon 3s ease-in-out infinite;
        }
        @keyframes floatIcon {
            0%,
            100% {
                transform: translateY(0);
            }
            50% {
                transform: translateY(-10px);
            }
        }
        .empty-state h3 {
            font-weight: 700;
            font-size: 18px;
            color: var(--text-primary);
            letter-spacing: 0.2px;
        }
        .empty-state p {
            font-size: 13px;
            color: var(--text-secondary);
            max-width: 280px;
            line-height: 1.5;
        }

        /* 响应式处理 */
        @media (max-width: 768px) {
            .sidebar {
                width: 100%;
                min-width: 100%;
            }
            .message-wrapper {
                max-width: 85%;
            }
            .chat-header {
                padding: 10px 14px;
            }
            .input-area {
                padding: 8px 10px 12px;
                gap: 6px;
            }
            .input-area .attach-btn {
                width: 36px;
                height: 36px;
                border-radius: 10px;
            }
            .send-btn {
                width: 40px;
                height: 40px;
                border-radius: 12px;
            }
            .input-wrapper textarea {
                font-size: 13px;
                padding: 8px 10px;
            }
        }

        @media (max-width: 400px) {
            .sidebar-header {
                padding: 14px 12px 8px;
            }
            .search-wrapper {
                padding: 6px 12px 12px;
            }
            .contact-card {
                padding: 8px 10px;
                gap: 8px;
                border-radius: 12px;
            }
            .avatar {
                width: 38px;
                height: 38px;
                border-radius: 11px;
                font-size: 14px;
            }
            .avatar.avatar-sm {
                width: 34px;
                height: 34px;
                border-radius: 10px;
                font-size: 12px;
            }
            .contact-card .contact-name {
                font-size: 13px;
            }
            .contact-card .contact-preview {
                font-size: 11.5px;
            }
            .message-wrapper {
                max-width: 90%;
            }
        }

/* ===== 新对话搜索弹窗 ===== */
.modal-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: var(--overlay);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
}
.modal-box {
    background: var(--bg-secondary);
    border-radius: 20px;
    padding: 24px;
    width: min(440px, 90vw);
    max-height: 70vh;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
}
.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}
.modal-header h3 {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}
.modal-close {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--text-tertiary);
    padding: 4px 8px;
    border-radius: 8px;
}
.modal-close:hover { background: var(--bg-hover); }
.modal-box input[type="text"] {
    width: 100%;
    padding: 12px 16px;
    border: 1.5px solid var(--border-color);
    border-radius: 14px;
    font-size: 14px;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    margin-bottom: 12px;
    font-family: inherit;
    transition: all 0.3s ease;
}
.modal-box input[type="text"]:focus {
    outline: none;
    border-color: var(--accent-1);
    box-shadow: 0 0 0 4px var(--accent-glow);
}
.search-results {
    overflow-y: auto;
    max-height: 50vh;
}
.search-result-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 12px;
    cursor: pointer;
    transition: background 0.2s;
}
.search-result-item:hover { background: var(--bg-hover); }
.search-result-info {
    flex: 1;
    display: flex;
    flex-direction: column;
}
.search-result-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
}
.search-result-username {
    font-size: 12px;
    color: var(--text-tertiary);
}
/* ===== 退出按钮样式 ===== */
#logoutBtn:hover { background: rgba(239, 68, 68, 0.1); color: #ef4444; }
/* ===== 右键菜单 ===== */
.context-menu {
    position: fixed;
    background: var(--bg-secondary);
    border-radius: 12px;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-color);
    z-index: 2000;
    overflow: hidden;
    min-width: 150px;
    animation: fadeIn 0.15s ease;
}
.context-item {
    padding: 10px 16px;
    font-size: 13px;
    cursor: pointer;
    transition: background 0.15s;
    color: var(--text-primary);
}
.context-item:hover { background: var(--bg-hover); }
.context-item.danger { color: var(--danger); }

/* ===== 表情选择器 ===== */
.emoji-picker {
    position: absolute;
    bottom: 100%;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    box-shadow: var(--shadow-md);
    max-height: 240px;
    overflow-y: auto;
    z-index: 100;
    padding: 8px;
}
.emoji-grid {
    display: grid;
    grid-template-columns: repeat(10, 1fr);
    gap: 2px;
}
.emoji-item {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    padding: 6px;
    cursor: pointer;
    border-radius: 8px;
    transition: background 0.15s, transform 0.15s;
}
.emoji-item:hover {
    background: var(--bg-hover);
    transform: scale(1.2);
}

/* ===== 消息中的文件/图片 ===== */
.message-image img {
    max-width: 260px;
    max-height: 300px;
    border-radius: 12px;
    cursor: pointer;
    transition: opacity 0.2s;
}
.message-image img:hover { opacity: 0.9; }
.message-video video {
    max-width: 300px;
    max-height: 300px;
    border-radius: 12px;
}
.message-audio audio {
    width: 240px;
    height: 36px;
}
.file-link {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    color: inherit;
    font-size: 13px;
    padding: 4px 0;
}
.file-link:hover { text-decoration: underline; }
.file-size {
    font-size: 11px;
    opacity: 0.6;
    margin-left: auto;
}

/* ===== 用户设置弹窗 ===== */
.profile-modal {
    max-height: 80vh;
    overflow-y: auto;
}
.profile-avatar-section {
    text-align: center;
    margin-bottom: 20px;
}
.avatar-lg {
    width: 72px;
    height: 72px;
    font-size: 24px;
    border-radius: 20px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 700;
}
.profile-form .form-group {
    margin-bottom: 14px;
}
.profile-form .form-group label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 4px;
}
.profile-form .form-group input {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border-color);
    border-radius: 12px;
    font-size: 14px;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    font-family: inherit;
}
.profile-form .form-group input:focus {
    outline: none;
    border-color: var(--accent-1);
}

/* ===== 群成员列表 ===== */
.members-list {
    max-height: 400px;
    overflow-y: auto;
}
.member-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 4px;
}
.member-name {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    flex: 1;
}
.member-tag {
    font-size: 11px;
    background: var(--accent-1);
    color: #fff;
    padding: 1px 8px;
    border-radius: 10px;
}

/* ===== 新对话弹窗扩展 ===== */
.modal-footer {
    margin-top: 12px;
    padding-top: 12px;
    border-top: 1px solid var(--border-color);
}
.group-mode-btn {
    width: 100%;
    padding: 10px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    color: var(--text-primary);
    transition: all 0.2s;
    font-family: inherit;
}
.group-mode-btn:hover { background: var(--bg-hover); }
.selected-members {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 10px;
}
.selected-member {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 10px;
    background: var(--accent-1);
    color: #fff;
    border-radius: 16px;
    font-size: 12px;
    font-weight: 500;
}
.remove-member {
    cursor: pointer;
    font-size: 14px;
    opacity: 0.7;
}
.remove-member:hover { opacity: 1; }
.modal-footer-actions {
    display: flex;
    gap: 8px;
}
.back-btn-sm {
    flex: 1;
    padding: 10px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    font-size: 13px;
    cursor: pointer;
    color: var(--text-primary);
    font-family: inherit;
}
.create-group-btn {
    flex: 2;
    padding: 10px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    border-radius: 12px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    font-family: inherit;
}
.check-mark {
    color: var(--accent-1);
    font-weight: 700;
    font-size: 16px;
}
.search-result-item.selected {
    background: var(--bg-active);
}

/* ===== 消息动画 ===== */
@keyframes messageIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* ===== 个人资料查看 ===== */
.profile-view { text-align: center; padding: 10px 0; }
.profile-name { font-size: 20px; font-weight: 700; color: var(--text-primary); margin: 12px 0 4px; }
.profile-username { font-size: 13px; color: var(--text-tertiary); margin-bottom: 8px; }
.profile-bio { font-size: 14px; color: var(--text-secondary); margin-bottom: 8px; padding: 0 20px; }
.profile-status { font-size: 13px; margin-bottom: 16px; }
.profile-actions { display: flex; flex-direction: column; gap: 8px; margin-top: 16px; }
.remove-friend-btn {
    padding: 10px; background: none; border: 1px solid var(--danger); color: var(--danger);
    border-radius: 14px; font-size: 13px; cursor: pointer; font-family: inherit;
}
.remove-friend-btn:hover { background: rgba(239,68,68,0.1); }

/* ===== 好友标签 ===== */
.friend-badge {
    font-size: 11px; color: var(--online-color); background: rgba(34,197,94,0.1);
    padding: 2px 8px; border-radius: 10px; font-weight: 500;
}
.add-friend-badge {
    font-size: 11px; color: var(--accent-1); background: var(--accent-glow);
    padding: 2px 8px; border-radius: 10px; font-weight: 600; cursor: pointer;
}
.add-friend-badge:hover { opacity: 0.8; }
.add-member-action {
    font-size: 12px; color: var(--accent-1); font-weight: 600; cursor: pointer;
}
.member-item { cursor: pointer; }
/* ===== Avatar Sizes ===== */
.avatar-xs { width: 28px; height: 28px; font-size: 10px; border-radius: 8px; display: inline-flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; flex-shrink: 0; }
.avatar-xl { width: 80px; height: 80px; font-size: 28px; border-radius: 22px; display: inline-flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; }
.avatar img, img.avatar { width: 100%; height: 100%; object-fit: cover; border-radius: inherit; }
.avatar-clickable img { border-radius: 22px; }

/* ===== Buttons ===== */
.btn-primary { padding: 11px 20px; background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: #fff; border: none; border-radius: 14px; font-size: 14px; font-weight: 600; cursor: pointer; transition: all 0.2s; box-shadow: 0 4px 14px rgba(102,126,234,0.3); font-family: inherit; }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 6px 20px rgba(102,126,234,0.4); }
.btn-primary:active { transform: scale(0.98); }
.btn-secondary { padding: 11px 20px; background: var(--bg-tertiary); color: var(--text-primary); border: 1.5px solid var(--border-color); border-radius: 14px; font-size: 14px; font-weight: 500; cursor: pointer; transition: all 0.2s; font-family: inherit; }
.btn-secondary:hover { background: var(--bg-hover); }
.btn-danger-outline { padding: 11px 20px; background: none; color: var(--danger); border: 1.5px solid var(--danger); border-radius: 14px; font-size: 14px; cursor: pointer; transition: all 0.2s; font-family: inherit; }
.btn-danger-outline:hover { background: rgba(239,68,68,0.08); }

/* ===== Search Results ===== */
.search-item { display: flex; align-items: center; gap: 12px; padding: 10px 12px; border-radius: 14px; cursor: pointer; transition: background 0.15s; }
.search-item:hover { background: var(--bg-hover); }
.search-item-avatar { flex-shrink: 0; cursor: pointer; }
.search-item-info { flex: 1; min-width: 0; }
.search-item-name { display: block; font-size: 14px; font-weight: 600; color: var(--text-primary); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.search-item-user { display: block; font-size: 12px; color: var(--text-tertiary); }
.search-item-actions { flex-shrink: 0; }
.search-empty { text-align: center; padding: 24px; color: var(--text-tertiary); font-size: 13px; }
.contacts-empty { text-align: center; padding: 40px; color: var(--text-tertiary); }

/* ===== Tags ===== */
.tag-friend { font-size: 11px; color: var(--online-color); background: rgba(34,197,94,0.1); padding: 3px 10px; border-radius: 12px; font-weight: 600; }
.tag-pending { font-size: 11px; color: var(--typing-color); background: rgba(245,158,11,0.1); padding: 3px 10px; border-radius: 12px; font-weight: 500; }
.tag-me { font-size: 10px; background: var(--accent-1); color: #fff; padding: 1px 8px; border-radius: 10px; margin-left: 6px; }
.btn-add-friend { font-size: 12px; color: #fff; background: var(--accent-1); border: none; padding: 4px 12px; border-radius: 12px; cursor: pointer; font-weight: 600; font-family: inherit; transition: all 0.2s; }
.btn-add-friend:hover { opacity: 0.85; }

/* ===== Plus Dropdown Menu ===== */
.plus-dropdown { position: fixed; background: var(--bg-secondary); border-radius: 14px; box-shadow: var(--shadow-lg); border: 1px solid var(--border-color); z-index: 2000; overflow: hidden; min-width: 160px; animation: fadeIn 0.15s ease; }
.plus-item { padding: 12px 16px; font-size: 13px; font-weight: 500; cursor: pointer; transition: background 0.15s; color: var(--text-primary); display: flex; align-items: center; gap: 8px; }
.plus-item:hover { background: var(--bg-hover); }
.plus-badge { background: #ff4757; color: #fff; font-size: 10px; font-weight: 700; min-width: 18px; height: 18px; border-radius: 9px; display: inline-flex; align-items: center; justify-content: center; padding: 0 5px; margin-left: auto; }

/* ===== Request Badge ===== */
.header-actions { position: relative; }
.req-badge { position: absolute; top: -4px; right: -4px; background: #ff4757; color: #fff; font-size: 10px; font-weight: 700; min-width: 16px; height: 16px; border-radius: 8px; display: flex; align-items: center; justify-content: center; padding: 0 4px; pointer-events: none; animation: badgePop 0.3s ease; }
@keyframes badgePop { 0% { transform: scale(0); } 50% { transform: scale(1.2); } 100% { transform: scale(1); } }

/* ===== Modal ===== */
.modal-wide { max-width: 480px; max-height: 85vh; overflow-y: auto; }
@media (max-width: 768px) {
    .modal-wide { max-width: 95vw; max-height: 90vh; padding: 20px 16px; }
    .modal-box { max-height: 85vh; overflow-y: auto; }
    .profile-modal { max-height: 85vh; overflow-y: auto; }
}
.modal-btn-row { display: flex; gap: 8px; margin-top: 16px; }
.modal-btn-row .btn-primary, .modal-btn-row .btn-secondary { flex: 1; }

/* ===== Selected Chips (group creation) ===== */
.selected-chips { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 8px; }
.selected-chip { display: inline-flex; align-items: center; gap: 4px; padding: 5px 12px; background: var(--accent-1); color: #fff; border-radius: 20px; font-size: 12px; font-weight: 600; }
.chip-x { cursor: pointer; font-size: 14px; opacity: 0.7; margin-left: 2px; }
.chip-x:hover { opacity: 1; }

/* ===== Profile View ===== */
.profile-view { text-align: center; padding: 10px 0; }
.profile-avatar-wrap { margin-bottom: 16px; }
.profile-name { font-size: 20px; font-weight: 700; color: var(--text-primary); margin: 0 0 4px; }
.profile-username { font-size: 13px; color: var(--text-tertiary); margin: 0 0 8px; }
.profile-bio { font-size: 14px; color: var(--text-secondary); margin: 0 0 8px; }
.profile-status { font-size: 13px; margin: 0 0 20px; }
.status-online { color: var(--online-color); }
.status-offline { color: var(--text-tertiary); }
.profile-me { text-align: center; padding: 12px; color: var(--text-tertiary); font-size: 13px; }
.profile-pending { text-align: center; padding: 12px; color: var(--typing-color); font-size: 13px; }
.profile-actions { display: flex; flex-direction: column; gap: 8px; }

/* ===== Settings ===== */
.settings-section { padding: 0 4px; }
.settings-title { font-size: 15px; font-weight: 700; color: var(--text-primary); margin-bottom: 14px; }
.settings-divider { height: 1px; background: var(--border-color); margin: 20px 0; }
.settings-avatar { text-align: center; margin-bottom: 20px; cursor: pointer; }
.avatar-clickable { display: inline-block; position: relative; }
.avatar-edit-hint { margin-top: 8px; font-size: 12px; color: var(--accent-1); font-weight: 500; opacity: 0.8; }
.settings-avatar:hover .avatar-edit-hint { opacity: 1; }
.settings-avatar:hover .avatar-clickable { transform: scale(1.05); transition: transform 0.2s; }

/* ===== Group Messages - Sender Info ===== */
.msg-sender { display: flex; align-items: center; gap: 6px; margin-bottom: 4px; }
.msg-sender-avatar { flex-shrink: 0; }
.msg-sender-name { font-size: 11px; font-weight: 600; color: var(--accent-1); }

/* ===== Member List ===== */
.member-row { display: flex; align-items: center; gap: 10px; padding: 8px 4px; cursor: pointer; border-radius: 10px; transition: background 0.15s; }
.member-row:hover { background: var(--bg-hover); }
.member-name { font-size: 14px; font-weight: 500; color: var(--text-primary); flex: 1; }

/* ===== Form ===== */
.form-group { margin-bottom: 14px; }
.form-group label { display: block; font-size: 12px; font-weight: 600; color: var(--text-secondary); margin-bottom: 5px; }
.form-group input { width: 100%; padding: 10px 14px; border: 1.5px solid var(--border-color); border-radius: 12px; font-size: 14px; background: var(--bg-tertiary); color: var(--text-primary); font-family: inherit; transition: all 0.2s; }
.form-group input:focus { outline: none; border-color: var(--accent-1); box-shadow: 0 0 0 3px var(--accent-glow); }
.form-group input:disabled { opacity: 0.5; cursor: not-allowed; }

/* ===== Loading ===== */
.loading-msg { text-align: center; padding: 40px; color: var(--text-tertiary); }

/* ===== Context Menu ===== */
.context-menu { position: fixed; background: var(--bg-secondary); border-radius: 14px; box-shadow: var(--shadow-lg); border: 1px solid var(--border-color); z-index: 2000; overflow: hidden; min-width: 150px; animation: fadeIn 0.15s ease; }
.context-item { padding: 10px 16px; font-size: 13px; cursor: pointer; transition: background 0.15s; color: var(--text-primary); }
.context-item:hover { background: var(--bg-hover); }
.context-item.danger { color: var(--danger); }

/* ===== Sidebar Tabs ===== */
.sidebar-tabs { display: flex; border-bottom: 1px solid var(--border-color); background: var(--bg-secondary); }
.stab { flex: 1; text-align: center; padding: 10px 0; font-size: 13px; font-weight: 600; color: var(--text-tertiary); cursor: pointer; transition: all 0.2s; border-bottom: 2px solid transparent; }
.stab:hover { color: var(--text-secondary); background: var(--bg-hover); }
.stab.active { color: var(--accent-1); border-bottom-color: var(--accent-1); }

/* ===== Tab Content ===== */
.tab-content { display: none; overflow-y: auto; flex: 1; }
.tab-header { padding: 10px 16px; display: flex; justify-content: space-between; align-items: center; }
.tab-count { font-size: 12px; color: var(--text-tertiary); font-weight: 500; }
.tab-section-title { padding: 8px 16px; font-size: 11px; font-weight: 700; color: var(--text-tertiary); text-transform: uppercase; letter-spacing: 0.5px; }
.tab-empty { text-align: center; padding: 40px 20px; color: var(--text-tertiary); font-size: 13px; }

/* ===== Friend Card ===== */
.friend-card { display: flex; align-items: center; gap: 12px; padding: 10px 16px; cursor: pointer; transition: background 0.15s; }
.friend-card:hover { background: var(--bg-hover); }
.friend-info { flex: 1; min-width: 0; }
.friend-name { display: block; font-size: 14px; font-weight: 600; color: var(--text-primary); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.friend-user { display: block; font-size: 11px; color: var(--text-tertiary); margin-top: 1px; }
.friend-actions { display: flex; gap: 6px; flex-shrink: 0; }
.btn-accept, .btn-decline, .btn-chat, .btn-remove {
    width: 32px; height: 32px; border-radius: 10px; border: none; cursor: pointer;
    display: flex; align-items: center; justify-content: center; font-size: 14px;
    transition: all 0.2s; font-family: inherit;
}
.btn-accept { background: rgba(34,197,94,0.12); color: var(--online-color); }
.btn-accept:hover { background: var(--online-color); color: #fff; }
.btn-decline { background: rgba(239,68,68,0.08); color: var(--danger); }
.btn-decline:hover { background: var(--danger); color: #fff; }
.btn-chat { background: var(--accent-glow); color: var(--accent-1); }
.btn-chat:hover { background: var(--accent-1); color: #fff; }
.btn-remove { background: rgba(239,68,68,0.06); color: var(--text-tertiary); }
.btn-remove:hover { background: var(--danger); color: #fff; }