:root {
    --primary-blue: #1A365D;
    --secondary-blue: #2B6CB0;
    --light-blue: #EBF8FF;
    --background-color: #F7FAFC;
    --card-bg: #FFFFFF;
    --text-main: #2D3748;
    --text-muted: #718096;
    --accent-orange: #ED8936;
    --accent-green: #48BB78;
    --border-color: #E2E8F0;
    --mascot-purple: #9F7AEA;

    --sidebar-width: 250px;
    --sidebar-collapsed-width: 70px;
    
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
}

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

body {
    font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
    background-color: var(--background-color);
    color: var(--text-main);
    display: flex;
    min-height: 100vh;
    overflow-x: hidden;
}

/* Sidebar */
.sidebar {
    width: var(--sidebar-width);
    background-color: var(--card-bg);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transition: width 0.3s ease;
    z-index: 100;
}

.sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
}

.sidebar-header {
    height: 70px;
    display: flex;
    align-items: center;
    padding: 0 1.5rem;
    border-bottom: 1px solid var(--border-color);
    color: var(--primary-blue);
    font-weight: 700;
    font-size: 1.25rem;
    overflow: hidden;
    white-space: nowrap;
}

.sidebar.collapsed .sidebar-header .logo-text {
    display: none;
}

.nav-links {
    list-style: none;
    padding: 1rem 0;
    flex-grow: 1;
}

.nav-item {
    margin-bottom: 0.5rem;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 0.75rem 1.5rem;
    color: var(--text-muted);
    text-decoration: none;
    transition: all 0.2s ease;
    white-space: nowrap;
    overflow: hidden;
}

.nav-link:hover, .nav-item.active .nav-link {
    background-color: var(--light-blue);
    color: var(--primary-blue);
    border-right: 3px solid var(--secondary-blue);
}

.nav-icon {
    width: 24px;
    height: 24px;
    margin-right: 1rem;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.nav-text {
    transition: opacity 0.3s ease;
}

.sidebar.collapsed .nav-text {
    opacity: 0;
    display: none;
}

.sidebar-toggle {
    background: none;
    border: none;
    cursor: pointer;
    padding: 1rem;
    color: var(--text-muted);
    border-top: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
    align-items: center;
}

.sidebar-toggle:hover {
    color: var(--primary-blue);
    background-color: var(--light-blue);
}

/* Main Content */
.main-content {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    min-width: 0; /* Important for flex child truncation */
    transition: margin-left 0.3s ease;
}

.top-header {
    height: 70px;
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 2rem;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background-color: var(--mascot-purple);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.content-area {
    padding: 2rem;
    flex-grow: 1;
    overflow-y: auto;
}

/* UI Components */
.page-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-blue);
    margin-bottom: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card {
    background-color: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    text-decoration: none;
    font-size: 0.875rem;
}

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

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

.btn-secondary {
    background-color: var(--light-blue);
    color: var(--secondary-blue);
}

.btn-secondary:hover {
    background-color: #dbeafe;
}

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

table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

th {
    padding: 1rem;
    border-bottom: 2px solid var(--border-color);
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-main);
    font-size: 0.875rem;
}

tbody tr:hover {
    background-color: var(--light-blue);
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
}

.badge-orange {
    background-color: #FEEBC8;
    color: #C05621;
}

.badge-green {
    background-color: #C6F6D5;
    color: #2F855A;
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        position: absolute;
        height: 100vh;
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
}