.sidebar {
    width: 400px;
    background-color: var(--sidebar-bg);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: row;
    height: 100%;
    box-shadow: var(--shadow-md);
    z-index: 10;
    min-width: 250px;
    max-width: 600px;
    transition: width 0.3s ease, min-width 0.3s ease;
}

.sidebar.collapsed {
    width: 60px !important;
    min-width: 60px !important;
}

.sidebar.collapsed .sidebar-panels {
    display: none;
}

@media (max-width: 768px) {
    .sidebar.collapsed {
        width: 85% !important;
        min-width: auto !important;
    }
    .sidebar.collapsed .sidebar-panels {
        display: flex;
    }
    .sidebar-nav {
        display: flex;
    }
    .hamburger-btn {
        display: none;
    }
}

.sidebar-nav {
    width: 60px;
    min-width: 60px;
    background-color: #f8fafc;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    padding-top: 16px;
    z-index: 11;
    overflow-y: auto;
}

.hamburger-btn {
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 8px;
    margin-bottom: 24px;
    border-radius: var(--radius-md);
    transition: background-color 0.2s;
}

.hamburger-btn:hover {
    background-color: var(--bg-color);
}

.nav-items {
    display: flex;
    flex-direction: column;
    gap: 16px;
    width: 100%;
    align-items: center;
}

.nav-item {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 10px;
    border-radius: var(--radius-md);
    transition: all 0.2s;
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 44px;
    height: 44px;
}

.nav-item:hover {
    background-color: var(--bg-color);
    color: var(--primary-color);
}

.nav-item.active {
    background-color: #eff6ff;
    color: var(--primary-color);
}

.nav-label {
    position: absolute;
    left: 100%;
    top: 50%;
    transform: translateY(-50%);
    margin-left: 10px;
    background-color: #334155;
    color: white;
    padding: 6px 10px;
    border-radius: 4px;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s;
    z-index: 100;
}

.nav-item:hover .nav-label {
    opacity: 1;
}

.sidebar-panels {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    background-color: var(--sidebar-bg);
    overflow: hidden;
}

.nav-panel {
    display: none;
}

.nav-panel.active {
    display: block;
}

.sidebar-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.sidebar-content {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Panels */
.panel {
    display: flex;
    flex-direction: column;
    gap: 16px;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 16px;
    box-shadow: var(--shadow-sm);
}

.panel.collapsible > h2,
.panel.collapsible > .panel-header {
    cursor: pointer;
    user-select: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: -16px;
    padding: 16px;
    border-radius: var(--radius-lg);
    transition: background-color 0.2s;
}

.panel.collapsible > h2:hover,
.panel.collapsible > .panel-header:hover {
    background-color: var(--bg-color);
}

.panel.collapsible > h2::after,
.panel.collapsible > .panel-header::after {
    content: '▼';
    font-size: 0.75rem;
    transition: transform 0.3s;
    color: var(--text-secondary);
}

.panel.collapsible.collapsed > h2::after,
.panel.collapsible.collapsed > .panel-header::after {
    transform: rotate(-90deg);
}

.panel.collapsible.collapsed > *:not(h2):not(.panel-header) {
    display: none;
}

.panel h2 {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
    font-weight: 600;
}

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

.flex-grow {
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
}

/* Mobile Sidebar Toggle */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-primary);
    cursor: pointer;
    padding: 8px;
    z-index: 100;
}

.mobile-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.5);
    z-index: 9;
    backdrop-filter: blur(2px);
}