:root {
    --sidebar-bg: #1a237e;
    --sidebar-text: rgba(255, 255, 255, 0.75);
    --sidebar-active-bg: rgba(255, 255, 255, 0.12);
    --sidebar-active-text: #ffffff;
    --sidebar-width: 240px;

    --body-bg: #f4f6fb;
    --card-bg: #ffffff;
    --card-radius: 10px;
    --card-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);

    --primary: #1a237e;
    --primary-hover: #3949ab;

    --table-header-bg: #f8f9ff;
    --table-row-hover: #f0f4ff;

    --input-editable-bg: #fffde7;
    --input-editable-border: #fbc02d;
    --input-radius: 6px;
    --focus-ring: rgba(57, 73, 171, 0.15);

    --kpi-blue: linear-gradient(135deg, #1565c0, #1e88e5);
    --kpi-green: linear-gradient(135deg, #2e7d32, #43a047);
    --kpi-orange: linear-gradient(135deg, #e65100, #fb8c00);
    --kpi-purple: linear-gradient(135deg, #6a1b9a, #8e24aa);

    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-size-base: 0.9rem;
    --topbar-height: 56px;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    background: var(--body-bg);
    margin: 0;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    z-index: 1000;
    overflow-y: auto;
}

.sidebar .nav-link {
    color: var(--sidebar-text);
    padding: 10px 20px;
    font-size: 0.88rem;
    border-radius: 6px;
    margin: 2px 12px;
    transition: all 0.15s;
}

.sidebar .nav-link:hover {
    background: var(--sidebar-active-bg);
    color: var(--sidebar-active-text);
}

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

/* Main content */
.main-content {
    margin-left: var(--sidebar-width);
    padding: 24px;
    min-height: 100vh;
}

/* Cards */
.card {
    background: var(--card-bg);
    border-radius: var(--card-radius);
    box-shadow: var(--card-shadow);
    border: none;
}

/* KPI Cards */
.kpi-card {
    border-radius: var(--card-radius);
    padding: 20px;
    color: #ffffff;
}
.kpi-card.blue { background: var(--kpi-blue); }
.kpi-card.green { background: var(--kpi-green); }
.kpi-card.orange { background: var(--kpi-orange); }
.kpi-card.purple { background: var(--kpi-purple); }

.kpi-card .kpi-value {
    font-size: 2rem;
    font-weight: 700;
}
.kpi-card .kpi-label {
    font-size: 0.8rem;
    opacity: 0.85;
    margin-top: 4px;
}

/* Tables */
.table thead th {
    background: var(--table-header-bg);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
    color: #555;
    border-bottom: 1px solid #e8eaf6;
    padding: 10px 12px;
}

.table tbody tr:hover {
    background: var(--table-row-hover);
}

.table tbody td {
    padding: 10px 12px;
    vertical-align: middle;
}

/* Buttons */
.btn-primary {
    background: var(--primary);
    border-color: var(--primary);
    border-radius: var(--input-radius);
}
.btn-primary:hover {
    background: var(--primary-hover);
    border-color: var(--primary-hover);
}

/* Inputs */
.form-control, .form-select {
    border-radius: var(--input-radius);
    font-size: 0.9rem;
}
.form-control:focus, .form-select:focus {
    box-shadow: 0 0 0 3px var(--focus-ring);
    border-color: var(--primary);
}

.form-control.editable {
    background: var(--input-editable-bg);
    border-color: var(--input-editable-border);
}

/* Status badges */
.badge-active { background: #43a047; }
.badge-stopped { background: #e53935; }
.badge-scheduled { background: #fb8c00; }
.badge-completed { background: #1e88e5; }
.badge-stale { background: #ff9800; }
.badge-untagged { background: #9e9e9e; }

/* Status dots */
.status-dot {
    display: inline-block;
    width: 10px;
    height: 10px;
    border-radius: 50%;
    margin-right: 4px;
}
.status-dot.on { background: #43a047; }
.status-dot.off { background: #e53935; }
.status-dot.stale { background: #ff9800; }

/* Mobile */
@media (max-width: 767.98px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    .sidebar.open {
        transform: translateX(0);
    }
    .main-content {
        margin-left: 0;
        padding-top: calc(var(--topbar-height) + 16px);
    }
    .topbar-mobile {
        display: flex;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        height: var(--topbar-height);
        background: var(--sidebar-bg);
        color: white;
        align-items: center;
        padding: 0 16px;
        z-index: 999;
    }
}

@media (min-width: 768px) {
    .topbar-mobile {
        display: none !important;
    }
}