/* ===== 标准侧边栏样式 - 所有页面统一使用 ===== */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: 260px;
    height: 100vh;
    background: #1e293b;
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: all 0.3s ease;
    overflow: hidden;
}

.sidebar-header {
    padding: 1.2rem;
    text-align: center;
    border-bottom: 1px solid rgba(255,255,255,0.06);
}

.sidebar-logo {
    width: auto;
    max-width: 74px;
    height: auto;
    background: transparent;
    border: none;
    border-radius: 0;
    display: block;
    padding: 0;
    margin: 0 auto 6px;
    box-sizing: border-box;
    flex-shrink: 0;
}

.sidebar-logo img {
    width: 100%;
    height: auto;
    object-fit: contain;
    display: block;
    border-radius: 10px;
}

.sidebar-header h2 {
    display: none;
}

.sidebar-header p {
    font-size: 12px;
    color: #94a3b8;
    margin: 4px 0 0;
}

.online-users {
    padding: 0.5rem 1.5rem;
    font-size: 13px;
    color: #94a3b8;
    display: flex;
    align-items: center;
    gap: 6px;
}

.online-indicator {
    color: #10b981;
    font-size: 10px;
}

.sidebar-nav {
    flex: 1;
    padding: 0 0.75rem 1rem;
    overflow-y: auto;
    overflow-x: hidden;
}

.sidebar-nav::-webkit-scrollbar { width: 4px; }
.sidebar-nav::-webkit-scrollbar-thumb { background: #334155; border-radius: 2px; }

.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 0.75rem 1rem;
    color: #cbd5e1;
    text-decoration: none;
    font-size: 14px;
    border-radius: 8px;
    margin-bottom: 2px;
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
    white-space: nowrap;
}

.nav-item:hover {
    background: rgba(255,255,255,0.06);
    color: #e8edf4;
}

.nav-item.active {
    background: rgba(37, 99, 235, 0.15);
    color: #60a5fa;
}

.nav-icon {
    font-size: 18px;
    min-width: 22px;
    text-align: center;
    flex-shrink: 0;
}

.nav-icon svg {
    width: 20px;
    height: 20px;
    display: block;
}

.nav-text {
    flex: 1;
    font-weight: 500;
}

.nav-arrow {
    font-size: 10px;
    transition: transform 0.25s ease;
    opacity: 0.6;
    margin-left: auto;
}

.nav-group.expanded .nav-arrow {
    transform: rotate(180deg);
}

.nav-children {
    display: none;
    flex-direction: column;
    padding-left: 8px;
}

.nav-group.expanded .nav-children {
    display: flex;
}

.nav-child {
    padding: 0.6rem 1rem 0.6rem 2.5rem !important;
    font-size: 13px !important;
    opacity: 0.8;
}

.nav-child:hover {
    opacity: 1;
}

.nav-child.active {
    opacity: 1;
    color: #60a5fa !important;
}

.badge {
    background: #ef4444;
    color: white;
    font-size: 11px;
    font-weight: 600;
    padding: 1px 7px;
    border-radius: 10px;
    min-width: 20px;
    text-align: center;
}

.sidebar-footer {
    padding: 0.8rem 1.2rem;
    border-top: 1px solid rgba(255,255,255,0.06);
    text-align: center;
}

.sidebar-theme-btn {
    width: 100%;
    padding: 0.6rem;
    border: 1px solid #334155;
    border-radius: 8px;
    background: transparent;
    color: #cbd5e1;
    cursor: pointer;
    font-size: 13px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    transition: all 0.2s ease;
}

.sidebar-theme-btn:hover {
    background: rgba(255,255,255,0.06);
    color: #e8edf4;
}

.sidebar-version {
    font-size: 11px;
    color: #475569;
    margin-top: 8px;
}

/* 主内容区偏移（仅桌面） */
@media screen and (min-width: 769px) {
    .main-content {
        margin-left: 260px;
        min-height: 100vh;
    }
}