:root {
    --primary: #3b82f6;
    --primary-dark: #2563eb;
    --secondary: #64748b;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --info: #0ea5e9;
    --accent: #0ea5e9;
    --background: #f8fafc;
    --surface: #ffffff;
    --text: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --sidebar-width: 260px;
    --header-height: 70px;
    --radius: 12px;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

[data-theme="dark"] {
    --background: #0f172a;
    --surface: #1e293b;
    --text: #f8fafc;
    --text-muted: #94a3b8;
    --border: #334155;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.3), 0 2px 4px -2px rgb(0 0 0 / 0.3);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

body {
    background-color: var(--background);
    color: var(--text);
    transition: background-color 0.3s, color 0.3s;
    overflow-x: hidden;
}

[x-cloak] {
    display: none !important;
}

.layout {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--surface);
    border-right: 1px solid var(--border);
    position: fixed;
    height: 100vh;
    z-index: 100;
    transition: transform 0.3s, background-color 0.3s;
}

.sidebar-header {
    height: var(--header-height);
    display: flex;
    align-items: center;
    padding: 0 24px;
    border-bottom: 1px solid var(--border);
}

.sidebar-logo {
    font-weight: 800;
    font-size: 1.5rem;
    color: var(--primary);
    text-decoration: none;
    letter-spacing: -0.5px;
}

.sidebar-menu {
    padding: 24px 16px;
    list-style: none;
}

.menu-item {
    margin-bottom: 8px;
}

.menu-link {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    color: var(--text-muted);
    text-decoration: none;
    border-radius: var(--radius);
    transition: all 0.2s;
    font-weight: 500;
}

.menu-link:hover, .menu-link.active {
    background-color: var(--primary);
    color: #ffffff;
}

.menu-link i {
    margin-right: 12px;
    font-size: 1.25rem;
}

/* Submenu */
.sidebar-menu .submenu {
    list-style: none !important;
    padding-left: 20px !important;
    padding-top: 5px !important;
    padding-bottom: 5px !important;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.sidebar-menu .submenu-item {
    margin-bottom: 5px !important;
}

.sidebar-menu .submenu-link {
    display: flex !important;
    align-items: center !important;
    padding: 6px 16px !important;
    color: #4b5563 !important; /* Gris oscuro específico */
    text-decoration: none !important;
    border-radius: var(--radius);
    font-size: 14px !important;
    font-weight: 500 !important;
    line-height: 1.4 !important;
    font-family: 'Inter', sans-serif !important;
    transition: all 0.2s;
}

.sidebar-menu .submenu-link:hover, 
.sidebar-menu .submenu-link.active {
    background-color: var(--background);
    color: var(--primary) !important;
}

.menu-link .arrow {
    margin-left: auto;
    margin-right: 0;
    font-size: 1rem;
    transition: transform 0.3s;
}

.menu-link.open .arrow {
    transform: rotate(90deg);
}

/* Tabs */
.tab-btn {
    background: none;
    border: none;
    font-weight: 700;
    cursor: pointer;
    padding: 10px 0;
    font-size: 0.875rem;
    transition: all 0.2s;
    border-bottom: 2px solid transparent;
}

.tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.tab-btn.inactive {
    color: var(--text-muted);
}

.tab-btn.inactive:hover {
    color: var(--text);
}

/* Main Content */
.main {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

.header {
    height: var(--header-height);
    background-color: var(--surface);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    position: sticky;
    top: 0;
    z-index: 90;
    transition: background-color 0.3s;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.icon-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.25rem;
    cursor: pointer;
    position: relative;
    padding: 8px;
    border-radius: 50%;
    transition: background-color 0.2s;
}

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

.badge {
    position: absolute;
    top: 4px;
    right: 4px;
    background-color: var(--danger);
    color: white;
    font-size: 0.65rem;
    padding: 2px 5px;
    border-radius: 10px;
    font-weight: bold;
}

/* Content Area */
.content {
    padding: 32px;
    max-width: 1400px;
    margin: 0 auto;
}

.page-header {
    margin-bottom: 32px;
}

.page-title {
    font-size: 1.875rem;
    font-weight: 700;
}

/* KPI Cards */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    margin-bottom: 32px;
}

.card {
    background-color: var(--surface);
    border-radius: var(--radius);
    padding: 24px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    transition: transform 0.2s, background-color 0.3s;
}

.card:hover {
    transform: translateY(-4px);
}

.card-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 12px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.card-value {
    font-size: 2rem;
    font-weight: 700;
    display: flex;
    align-items: baseline;
    gap: 8px;
}

.card-sub {
    font-size: 0.875rem;
    margin-top: 8px;
}

.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.text-primary { color: var(--primary); }
.text-muted { color: var(--text-muted); }

/* Tables */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th {
    text-align: left;
    padding: 16px;
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--text-muted);
    border-bottom: 1px solid var(--border);
}

td {
    padding: 16px;
    border-bottom: 1px solid var(--border);
}

/* Utils */
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-4 { gap: 1rem; }
.mb-4 { margin-bottom: 1rem; }
.mt-8 { margin-top: 2rem; }

/* Dashboard Specific */
.dashboard-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 24px;
}

@media (max-width: 1024px) {
    .dashboard-grid {
        grid-template-columns: 1fr;
    }
    .sidebar {
        transform: translateX(-100%);
    }
    .main {
        margin-left: 0;
    }
}

/* Detail Tank Specific */
.tank-status {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    display: inline-block;
    margin-right: 8px;
}

.status-active { background-color: var(--success); }
.status-inactive { background-color: var(--danger); }

/* Map placeholder style */
#map {
    height: 400px;
    border-radius: var(--radius);
    z-index: 10;
}

/* Forms & Buttons */
.form-group {
    margin-bottom: 16px;
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.form-input {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background-color: var(--background);
    color: var(--text);
    font-size: 0.875rem;
    transition: all 0.2s;
    outline: none;
}

.form-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.btn-primary {
    background-color: var(--primary);
    color: #ffffff;
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    transition: background-color 0.2s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    text-decoration: none;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
}