:root {
    /* Premium Palette - Deep Blue & Vibrant Accents */
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #60a5fa;
    --secondary: #64748b;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --dark: #0f172a;
    --light: #f8fafc;
    --surface: #ffffff;
    --surface-alt: #f1f5f9;
    --border: #e2e8f0;
    
    --text-main: #1e293b;
    --text-muted: #64748b;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);

    --radius: 0.75rem;
    --header-height: 4rem;
    --sidebar-width: 260px;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--surface-alt);
    color: var(--text-main);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

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

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background: var(--dark);
    color: white;
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    z-index: 50;
    transition: transform 0.3s ease;
}

.brand {
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: white;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.logo-icon {
    font-size: 1.5rem;
    color: var(--primary-light);
}

.nav-menu {
    flex: 1;
    padding: 1.5rem 1rem;
    overflow-y: auto;
}

.nav-label {
    text-transform: uppercase;
    font-size: 0.75rem;
    font-weight: 600;
    color: rgba(255,255,255,0.4);
    margin-bottom: 0.75rem;
    margin-top: 1.5rem;
    padding-left: 0.75rem;
}
.nav-label:first-child { margin-top: 0; }

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    border-radius: 0.5rem;
    transition: all 0.2s;
    margin-bottom: 0.25rem;
}

.nav-item ion-icon { font-size: 1.25rem; }

.nav-item:hover, .nav-item.active {
    background: var(--primary);
    color: white;
}

.user-profile {
    padding: 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-info {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.user-name { font-weight: 600; font-size: 0.9rem; }
.user-role { font-size: 0.75rem; color: rgba(255,255,255,0.5); }

.logout-btn {
    color: rgba(255,255,255,0.6);
    font-size: 1.5rem;
    transition: 0.2s;
}
.logout-btn:hover { color: var(--danger); }

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

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

.page-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-main);
}

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

/* Forms (Install, Login) */
.auth-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--dark) 0%, #1e293b 100%);
    padding: 1rem;
}

.auth-card {
    background: var(--surface);
    padding: 2.5rem;
    border-radius: var(--radius);
    width: 100%;
    max-width: 450px;
    box-shadow: var(--shadow-lg);
}

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

.auth-header h1 {
    font-size: 1.5rem;
    color: var(--text-main);
    margin-bottom: 0.5rem;
}

.auth-header p { color: var(--text-muted); }

.form-group { margin-bottom: 1.25rem; }
.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-main);
    margin-bottom: 0.5rem;
}

.form-input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    font-family: inherit;
    font-size: 1rem;
    transition: 0.2s;
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: 0.2s;
    text-decoration: none;
    font-family: inherit;
    font-size: 0.95rem;
}

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

.btn-block { width: 100%; }

.alert {
    padding: 1rem;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}
.alert-error {
    background: #fee2e2;
    color: #b91c1c;
    border: 1px solid #fecaca;
}
.alert-success {
    background: #dcfce7;
    color: #15803d;
    border: 1px solid #bbf7d0;
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar { transform: translateX(-100%); }
    .main-content { margin-left: 0; }
    .content-wrapper { padding: 1rem; }
    
    /* Toggle for sidebar needed later */
}