:root {
    /* ULT Brand Colors - Clean White Theme */
    --brand-primary: #1e40af;     /* Deep Blue */
    --brand-secondary: #3b82f6;   /* Bright Blue */
    --brand-accent: #60a5fa;      /* Light Blue */
    
    /* Background Colors */
    --bg-primary: #ffffff;         /* Pure White */
    --bg-secondary: #f8fafc;      /* Light Gray */
    --bg-tertiary: #f1f5f9;       /* Soft Gray */
    --bg-card: #ffffff;           /* Card Background */
    
    /* Border Colors */
    --border-light: #e2e8f0;      /* Light Border */
    --border-medium: #cbd5e1;     /* Medium Border */
    --border-focus: #3b82f6;      /* Focus Border */
    
    /* Text Colors */
    --text-primary: #1e293b;      /* Dark Text */
    --text-secondary: #475569;    /* Medium Text */
    --text-tertiary: #64748b;     /* Light Text */
    --text-inverse: #ffffff;      /* White Text */
    
    /* Shadow Colors */
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* Reset and Base Styles */
* {
    box-sizing: border-box;
}

body { 
    font-family: 'Inter', 'Sarabun', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5em;
}

.font-display { 
    font-family: 'Poppins', 'Inter', sans-serif;
    font-weight: 700;
}

/* ULT Brand Text */
.ult-primary { 
    color: var(--brand-primary);
}

/* Main Container */
.main-container {
    min-height: 100vh;
    background-color: var(--bg-secondary);
}

/* Glass Morphism Effect (Subtle) */
.glass-pane {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-md);
}

/* Header */
header {
    background-color: var(--bg-primary) !important;
    border-bottom: 1px solid var(--border-light) !important;
    box-shadow: var(--shadow-sm);
}

/* Buttons */
.btn { 
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1.25rem;
    border-radius: 0.5rem;
    font-weight: 500;
    font-size: 0.875rem;
    transition: all 0.2s ease;
    cursor: pointer;
    border: 1px solid transparent;
    outline: none;
}

.btn:focus {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.btn-sm { 
    padding: 0.375rem 0.875rem;
    font-size: 0.8125rem;
}

.btn:disabled { 
    cursor: not-allowed;
    opacity: 0.6;
}

.btn-primary { 
    background-color: var(--brand-primary);
    color: var(--text-inverse);
    border-color: var(--brand-primary);
}

.btn-primary:hover:not(:disabled) { 
    background-color: var(--brand-secondary);
    border-color: var(--brand-secondary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-primary:active:not(:disabled) { 
    transform: translateY(0);
}

.btn-secondary { 
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border-color: var(--border-medium);
}

.btn-secondary:hover:not(:disabled) { 
    background-color: var(--bg-tertiary);
    border-color: var(--border-medium);
    color: var(--text-primary);
}

.btn-danger { 
    background-color: #ef4444;
    color: var(--text-inverse);
    border-color: #ef4444;
}

.btn-danger:hover:not(:disabled) { 
    background-color: #dc2626;
    border-color: #dc2626;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* Form Elements */
.form-input, 
.form-select, 
.form-textarea { 
    background-color: var(--bg-primary);
    border: 1px solid var(--border-light);
    color: var(--text-primary);
    border-radius: 0.5rem;
    padding: 0.625rem 0.875rem;
    transition: all 0.2s ease;
    width: 100%;
    font-size: 0.875rem;
}

.form-input:focus, 
.form-select:focus, 
.form-textarea:focus { 
    outline: none;
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-input:disabled,
.form-select:disabled,
.form-textarea:disabled { 
    background-color: var(--bg-tertiary);
    color: var(--text-tertiary);
    cursor: not-allowed;
}

.form-display { 
    background-color: var(--bg-tertiary);
    border: 1px solid var(--border-light);
    color: var(--text-primary);
    border-radius: 0.5rem;
    padding: 0.625rem 0.875rem;
    width: 100%;
    min-height: 42px;
}

/* Portal Menu Items */
.portal-menu-item { 
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 1.25rem;
    border-radius: 1rem;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-light);
    color: var(--text-secondary);
    font-weight: 500;
    transition: all 0.2s ease;
    cursor: pointer;
    text-align: center;
    position: relative;
    min-height: 110px;
    box-shadow: var(--shadow-sm);
}

.portal-menu-item:hover { 
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--brand-accent);
    background-color: var(--bg-primary);
}

.portal-menu-item.active { 
    background-color: var(--brand-primary);
    border-color: var(--brand-primary);
    color: var(--text-inverse);
    box-shadow: var(--shadow-md);
}

.portal-menu-item.active:hover {
    background-color: var(--brand-secondary);
    border-color: var(--brand-secondary);
}

/* Notification Indicators */
.notification-dot { 
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    width: 0.625rem;
    height: 0.625rem;
    background-color: #ef4444;
    border-radius: 50%;
    border: 2px solid var(--bg-primary);
    box-shadow: var(--shadow-sm);
}

.notification-badge { 
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    min-width: 1.25rem;
    height: 1.25rem;
    padding: 0 0.375rem;
    background-color: #ef4444;
    border-radius: 0.625rem;
    border: 2px solid var(--bg-primary);
    color: var(--text-inverse);
    font-size: 0.75rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    box-shadow: var(--shadow-sm);
}

/* Modal */
.modal-backdrop { 
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 40;
    opacity: 0;
    transition: opacity 0.3s ease;
    pointer-events: none;
}

.modal-backdrop.active { 
    opacity: 1;
    pointer-events: auto;
}

.modal-content { 
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.95);
    z-index: 50;
    transition: all 0.3s ease;
    opacity: 0;
    pointer-events: none;
    background-color: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: 1rem;
    box-shadow: var(--shadow-xl);
}

.modal-content.active { 
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
    pointer-events: auto;
}

/* Toast Notifications */
.toast-notification { 
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    padding: 0.875rem 1.25rem;
    border-radius: 0.5rem;
    color: var(--text-inverse);
    z-index: 100;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-lg);
    font-size: 0.875rem;
    font-weight: 500;
    max-width: 24rem;
}

.toast-notification.show {
    opacity: 1;
    transform: translateY(0);
}

.toast-success { 
    background-color: #10b981;
    border: 1px solid #059669;
}

.toast-error { 
    background-color: #ef4444;
    border: 1px solid #dc2626;
}

/* Loading Spinner */
.loading-spinner {
    border: 3px solid var(--border-light);
    border-top-color: var(--brand-primary);
    border-radius: 50%;
    width: 24px;
    height: 24px;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Animations */
.fade-in { 
    animation: fadeIn 0.4s ease-out;
}

@keyframes fadeIn { 
    from { 
        opacity: 0;
        transform: translateY(10px);
    }
    to { 
        opacity: 1;
        transform: translateY(0);
    }
}

/* Tables */
table {
    background-color: var(--bg-primary);
}

thead {
    background-color: var(--bg-tertiary) !important;
    border-bottom: 1px solid var(--border-light);
}

thead th {
    color: var(--text-secondary) !important;
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

tbody tr {
    border-bottom: 1px solid var(--border-light);
}

tbody tr:hover {
    background-color: var(--bg-secondary);
}

tbody td {
    color: var(--text-primary) !important;
    font-size: 0.875rem;
}

/* Cards and Panels */
.bg-slate-900\/50,
.bg-slate-900\/70,
.bg-slate-800,
.bg-slate-800\/50,
.bg-slate-700,
.bg-slate-700\/30 {
    background-color: var(--bg-primary) !important;
    border: 1px solid var(--border-light) !important;
    box-shadow: var(--shadow-sm);
}

/* Text Color Overrides */
.text-slate-300,
.text-slate-400,
.text-slate-500,
.text-slate-600 {
    color: var(--text-secondary) !important;
}

.text-white {
    color: var(--text-primary) !important;
}

/* Border Color Overrides */
.border-slate-700,
.border-slate-600 {
    border-color: var(--border-light) !important;
}

/* Special Elements */
#portal-content-area {
    margin-top: 1rem;
    background-color: var(--bg-primary);
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    padding: 1.5rem;
}

/* Manager Section */
#manager-section {
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-light);
}

/* Responsive Design */
@media (max-width: 640px) {
    .portal-menu-item {
        min-height: 90px;
        padding: 1rem;
    }
    
    #portal-content-area {
        padding: 1rem;
    }
}

/* Print Styles */
@media print {
    body {
        background-color: white;
    }
    
    .no-print {
        display: none !important;
    }
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background-color: var(--bg-tertiary);
}

::-webkit-scrollbar-thumb {
    background-color: var(--border-medium);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background-color: var(--text-tertiary);
}

/* Focus Visible */
*:focus-visible {
    outline: 2px solid var(--brand-accent);
    outline-offset: 2px;
}

/* Selection */
::selection {
    background-color: var(--brand-accent);
    color: var(--text-inverse);
}