:root {
    /* Color Palette - Modern & Clean */
    --primary-color: #2563eb;       /* Royal Blue */
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;     /* Slate */
    --accent-color: #f59e0b;        /* Amber */
    --danger-color: #ef4444;        /* Red */
    --success-color: #10b981;       /* Emerald */
    
    --bg-body: #f3f4f6;             /* Light Gray Background */
    --bg-card: #ffffff;             /* White Cards */
    
    --text-main: #111827;           /* Almost Black */
    --text-muted: #6b7280;          /* Gray Text */
    
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

    --font-main: 'Inter', sans-serif;
    --font-heading: 'Tajawal', sans-serif; /* Good for Arabic/English mix if needed */
}

/* Reset & Base */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-main);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color 0.2s;
}

a:hover {
    color: var(--primary-hover);
}

ul {
    list-style: none;
}

/* --- Layout --- */
.wrap {
    flex: 1;
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* --- Navigation Bar --- */
.main-header {
    background-color: var(--bg-card);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 50;
    border-bottom: 1px solid var(--border-color);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-family: var(--font-heading);
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--text-main);
}

.nav-logo {
    height: 40px;
    width: auto;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-link {
    color: var(--text-muted);
    font-weight: 500;
    font-size: 0.95rem;
    padding: 8px 12px;
    border-radius: 6px;
    transition: all 0.2s;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary-color);
    background-color: #eff6ff;
}

.nav-user-info {
    font-size: 0.9rem;
    color: var(--text-muted);
    padding-right: 15px;
    border-right: 1px solid var(--border-color);
    margin-right: 15px;
}

.btn-logout {
    color: var(--danger-color);
}

.btn-logout:hover {
    color: #b91c1c;
    background-color: #fef2f2;
}

/* --- Common Components --- */

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1.25rem;
    font-weight: 600;
    border-radius: 8px;
    transition: all 0.2s;
    cursor: pointer;
    border: 1px solid transparent;
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
    color: white;
    transform: translateY(-1px);
    box-shadow: 0 4px 6px -1px rgba(37, 99, 235, 0.2);
}

.btn-secondary {
    background-color: white;
    border-color: var(--border-color);
    color: var(--text-main);
}

.btn-secondary:hover {
    background-color: #f9fafb;
    border-color: #d1d5db;
}

/* Cards */
.card {
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    padding: 24px;
    border: 1px solid var(--border-color);
    transition: box-shadow 0.2s;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

/* Forms */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
input[type="time"],
select,
textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-family: var(--font-main);
    font-size: 1rem;
    transition: border-color 0.15s, box-shadow 0.15s;
    background-color: #fff;
}

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

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

/* --- Specific Page Styles --- */

/* Login / Landing */
.auth-container {
    max-width: 400px;
    margin: 60px auto;
    text-align: center;
}

.auth-card {
    background: white;
    padding: 40px;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
}

/* Dashboard */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
    margin-top: 24px;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 15px;
}

.stat-icon {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    background: #eff6ff;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

/* Messages */
.messages {
    max-width: 800px;
    margin: 20px auto;
}

.messages li {
    padding: 12px 16px;
    margin-bottom: 10px;
    border-radius: 8px;
    font-weight: 500;
}

.messages li.success {
    background-color: #d1fae5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.messages li.error {
    background-color: #fee2e2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

.messages li.warning {
    background-color: #fef3c7;
    color: #92400e;
    border: 1px solid #fde68a;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(4px);
    z-index: 9999;
    display: none; /* Hidden by default */
    justify-content: center;
    align-items: center;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav-container {
        height: auto;
        flex-direction: column;
        padding: 15px;
        gap: 15px;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav-user-info {
        display: none; /* Hide on mobile to save space */
    }
}