:root {
    --sidebar-width: 260px;
    --sidebar-collapsed-width: 64px;
    --sidebar-bg: var(--surface-color);
    --sidebar-border: var(--border-color);
    --sidebar-hover: var(--background-color);
    --sidebar-active-bg: rgba(37, 99, 235, 0.08);
    --sidebar-active-color: var(--primary-color);
    --sidebar-section-color: var(--text-secondary);
    --sidebar-transition: 0.2s ease;
    --topbar-height: 0px;
}

[data-theme="dark"] {
    --sidebar-active-bg: rgba(59, 130, 246, 0.12);
}

.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    border-right: 1px solid var(--sidebar-border);
    display: flex;
    flex-direction: column;
    z-index: 200;
    transition: width var(--sidebar-transition);
    overflow: hidden;
}

.sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
}

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

.sidebar-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 18px;
    border-bottom: 1px solid var(--sidebar-border);
    min-height: 64px;
    flex-shrink: 0;
}

.sidebar-logo {
    width: 28px;
    height: 28px;
    flex-shrink: 0;
    filter: drop-shadow(0 1px 2px rgba(0, 0, 0, 0.1));
}

.sidebar-brand-text {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    letter-spacing: -0.01em;
}

.sidebar-brand-sub {
    font-size: 0.65rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    white-space: nowrap;
    overflow: hidden;
}

.sidebar-nav {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 8px 0;
}

.sidebar-nav::-webkit-scrollbar {
    width: 4px;
}

.sidebar-nav::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 2px;
}

.sidebar-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 18px;
    color: var(--text-primary);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 450;
    border-radius: 0;
    transition: background var(--sidebar-transition), color var(--sidebar-transition);
    white-space: nowrap;
    position: relative;
}

.sidebar-link:hover {
    background: var(--sidebar-hover);
}

.sidebar-link.active {
    background: var(--sidebar-active-bg);
    color: var(--sidebar-active-color);
    font-weight: 600;
}

.sidebar-link.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 4px;
    bottom: 4px;
    width: 3px;
    background: var(--sidebar-active-color);
    border-radius: 0 2px 2px 0;
}

.sidebar-icon {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    opacity: 0.7;
}

.sidebar-link.active .sidebar-icon {
    opacity: 1;
}

.sidebar-label {
    overflow: hidden;
    text-overflow: ellipsis;
}

.sidebar-section {
    padding: 20px 18px 6px;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--sidebar-section-color);
    white-space: nowrap;
    overflow: hidden;
}

.sidebar-link.locked {
    opacity: 0.45;
    cursor: not-allowed;
}

.sidebar-link.locked:hover {
    background: transparent;
}

.sidebar-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 20px;
    padding: 0 6px;
    border-radius: 10px;
    font-size: 0.7rem;
    font-weight: 600;
    background: var(--error-color);
    color: #fff;
    margin-left: auto;
    flex-shrink: 0;
}

.sidebar-footer {
    border-top: 1px solid var(--sidebar-border);
    padding: 8px 0;
    flex-shrink: 0;
}

.sidebar-footer .sidebar-link {
    padding: 8px 18px;
    font-size: 0.85rem;
}

.sidebar-collapse-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    width: 100%;
    padding: 8px 18px;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 0.85rem;
    transition: background var(--sidebar-transition);
    white-space: nowrap;
}

.sidebar-collapse-btn:hover {
    background: var(--sidebar-hover);
}

.sidebar-collapse-icon {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
    transition: transform var(--sidebar-transition);
}

.sidebar-collapse-icon.rotated {
    transform: rotate(180deg);
}

.main-content {
    margin-left: var(--sidebar-width);
    transition: margin-left var(--sidebar-transition);
    min-height: 100vh;
}

body.sidebar-collapsed .main-content {
    margin-left: var(--sidebar-collapsed-width);
}

.footer {
    margin-left: var(--sidebar-width);
    transition: margin-left var(--sidebar-transition);
}

body.sidebar-collapsed .footer {
    margin-left: var(--sidebar-collapsed-width);
}

.hamburger {
    display: none;
    position: fixed;
    top: 12px;
    left: 12px;
    z-index: 300;
    width: 44px;
    height: 44px;
    background: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.hamburger img {
    width: 22px;
    height: 22px;
}

.sidebar-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 150;
}

@media (max-width: 1199px) and (min-width: 900px) {
    .sidebar {
        width: var(--sidebar-collapsed-width);
    }

    .sidebar-label,
    .sidebar-brand-text,
    .sidebar-brand-sub,
    .sidebar-section,
    .sidebar-collapse-label,
    .sidebar-badge {
        display: none;
    }

    .sidebar-link {
        justify-content: center;
        padding: 12px;
    }

    .sidebar-brand {
        justify-content: center;
        padding: 16px 12px;
    }

    .sidebar-collapse-btn {
        justify-content: center;
        padding: 10px;
    }

    .sidebar-footer .sidebar-link {
        justify-content: center;
        padding: 10px;
    }

    .main-content {
        margin-left: var(--sidebar-collapsed-width);
    }

    .footer {
        margin-left: var(--sidebar-collapsed-width);
    }

    .sidebar-link {
        position: relative;
    }

    .sidebar-link::after {
        content: attr(data-tooltip);
        position: absolute;
        left: calc(var(--sidebar-collapsed-width) + 4px);
        top: 50%;
        transform: translateY(-50%);
        background: var(--text-primary);
        color: var(--surface-color);
        padding: 4px 10px;
        border-radius: 4px;
        font-size: 0.8rem;
        white-space: nowrap;
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.15s;
        z-index: 1000;
    }

    .sidebar-link:hover::after {
        opacity: 1;
    }
}

@media (max-width: 899px) {
    .sidebar {
        width: var(--sidebar-width);
        transform: translateX(-100%);
        transition: transform var(--sidebar-transition);
        box-shadow: none;
    }

    body.mobile-menu-open .sidebar {
        transform: translateX(0);
        box-shadow: 4px 0 16px rgba(0, 0, 0, 0.15);
    }

    body.mobile-menu-open .sidebar-overlay {
        display: block;
    }

    .hamburger {
        display: flex;
    }

    .main-content {
        margin-left: 0;
        padding-top: 60px; 
    }

    .footer {
        margin-left: 0;
    }

    .sidebar-label,
    .sidebar-brand-text,
    .sidebar-brand-sub,
    .sidebar-section {
        display: block;
    }
}

body.kiosk-mode .sidebar,
body.kiosk-mode .hamburger,
body.kiosk-mode .sidebar-overlay {
    display: none !important;
}

body.kiosk-mode .main-content,
body.kiosk-mode .footer {
    margin-left: 0 !important;
}

body.no-sidebar .sidebar,
body.no-sidebar .hamburger,
body.no-sidebar .sidebar-overlay {
    display: none !important;
}

body.no-sidebar .main-content,
body.no-sidebar .footer {
    margin-left: 0 !important;
}