:root {
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --secondary-color: #64748b;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --warning-color: #f59e0b;
  --background-color: #f8fafc;
  --card-bg: #ffffff;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --radius: 0.5rem;
  --sidebar-width: 260px;
  --header-height: 64px;
}

[data-theme="dark"] {
  --background-color: #0f172a;
  --card-bg: #1e293b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --border-color: #334155;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.3);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.5);
}

[data-theme="dark"] .sidebar {
    background-color: var(--card-bg);
    border-right-color: var(--border-color);
}

[data-theme="dark"] .top-header {
    background-color: var(--card-bg);
    border-bottom-color: var(--border-color);
}

[data-theme="dark"] .nav-item:hover, [data-theme="dark"] .nav-item.active {
    background-color: rgba(255, 255, 255, 0.1);
}

[data-theme="dark"] .form-control {
    background-color: #0f172a;
    border-color: var(--border-color);
    color: var(--text-main);
}

[data-theme="dark"] .user-info-pill {
    background-color: var(--background-color);
}

[data-theme="dark"] .stat-card {
    background-color: var(--card-bg);
}

[data-theme="dark"] .monitor-card {
    background-color: #0f172a;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family:
    "Inter",
    system-ui,
    -apple-system,
    sans-serif;
  background-color: var(--background-color);
  color: var(--text-main);
  line-height: 1.5;
  transition: background-color 0.3s, color 0.3s;
}

a {
  text-decoration: none;
  color: var(--primary-color);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
}

/* Utilities */
.btn {
  display: inline-block;
  padding: 0.5rem 1rem;
  border-radius: var(--radius);
  font-weight: 500;
  cursor: pointer;
  border: none;
  transition: background-color 0.2s;
  text-align: center;
}

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

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

.btn-block {
  display: block;
  width: 100%;
}

.card {
  background-color: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
  border: 1px solid var(--border-color);
}

.form-group {
  margin-bottom: 1rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-main);
}

.form-control {
  width: 100%;
  padding: 0.5rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  font-family: inherit;
  font-size: 1rem;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Login Page Specific */
.login-page {
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
}

.login-card {
  width: 100%;
  max-width: 400px;
  padding: 2rem;
  background: white;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
}

.login-header {
  text-align: center;
  margin-bottom: 2rem;
}

.login-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--text-main);
}

.login-subtitle {
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* Alerts */
.alert {
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
}

.alert-danger {
  background-color: #fee2e2;
  color: #991b1b;
  border: 1px solid #fecaca;
}

.alert-success {
  background-color: #dcfce7;
  color: #166534;
  border: 1px solid #bbf7d0;
}

/* Dashboard Layout */
.app-wrapper {
    display: flex;
    min-height: 100vh;
}

/* Sidebar Redesign */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--primary-color); /* Dark Sidebar */
    color: white;
    border-right: none;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    flex-shrink: 0;
    /* display flex is inherited from column direction */
    display: flex;
    flex-direction: column;
    z-index: 50;
    transition: transform 0.3s ease;
    box-shadow: 4px 0 10px rgba(0,0,0,0.1);
}

.sidebar-header {
    height: var(--header-height);
    display: flex;
    align-items: center;
    padding: 0 1.5rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: white;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar-nav {
    padding: 1.5rem 1rem;
    flex: 1;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 0.85rem 1rem;
    margin-bottom: 0.5rem;
    color: rgba(255, 255, 255, 0.8);
    border-radius: var(--radius);
    transition: all 0.2s;
    font-weight: 500;
}

.nav-item:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: white;
    transform: translateX(5px);
}

.nav-item.active {
    background-color: rgba(255, 255, 255, 0.2);
    color: white;
    font-weight: 600;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    background-color: rgba(0,0,0,0.1);
}

/* Redesigned Stat Cards */
.stat-card {
    background: white;
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    border-left: 5px solid var(--primary-color); /* Accent border */
    display: flex;
    flex-direction: column;
    height: 100%;
    transition: transform 0.2s, box-shadow 0.2s;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
}

.stat-header {
    margin-bottom: 1rem;
}

.stat-label {
    color: var(--text-muted);
    font-size: 0.9rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.5rem;
    display: block;
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1;
    margin-bottom: 0.5rem;
}

.stat-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.stat-action {
    margin-top: auto;
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}

.main-content {
    flex: 1;
    margin-left: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.top-header {
    height: var(--header-height);
    background-color: white;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
    position: sticky;
    top: 0;
    z-index: 40;
}

.page-content {
    padding: 2rem;
    flex: 1;
}

.page-header {
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.page-title {
    font-size: 1.5rem;
    font-weight: 600;
}

/* Mobile Toggle */
.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-main);
}

/* Stats Cards */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.5rem;
    margin-bottom: 2rem;
}

@media (max-width: 1200px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }
}


/* Mobile Sidebar Overlay */
.sidebar-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 45; /* Below sidebar (50) but above everything else */
    display: none;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.sidebar-overlay.active {
    display: block;
    opacity: 1;
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        z-index: 2000;
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .menu-toggle {
        display: block;
        margin-right: 1rem;
    }
    
    .top-header {
        padding: 0 1rem;
        justify-content: flex-start;
    }

    .user-menu {
        margin-left: auto;
    }
}