/* ===== CSS Variables (Design System) ===== */
:root {
    /* Primary Colors */
    --primary-50: #eff6ff;
    --primary-100: #dbeafe;
    --primary-200: #bfdbfe;
    --primary-300: #93c5fd;
    --primary-400: #60a5fa;
    --primary-500: #3b82f6;
    --primary-600: #2563eb;
    --primary-700: #1d4ed8;
    --primary-800: #1e40af;
    --primary-900: #1e3a8a;

    /* Neutral Colors */
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;

    /* Semantic Colors */
    --success-500: #22c55e;
    --success-600: #16a34a;
    --warning-500: #f59e0b;
    --warning-600: #d97706;
    --danger-500: #ef4444;
    --danger-600: #dc2626;
    --info-500: #06b6d4;
    --info-600: #0891b2;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;

    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    --radius-2xl: 1rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 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);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 200ms ease;
    --transition-slow: 300ms ease;

    /* Layout */
    --sidebar-width: 260px;
    --sidebar-collapsed-width: 70px;
    --navbar-height: 64px;
}

/* ===== Reset & Base Styles ===== */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--gray-800);
    background-color: var(--gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--primary-600);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-700);
}

img {
    max-width: 100%;
    height: auto;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--gray-900);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }
h6 { font-size: var(--font-size-base); }

.text-muted {
    color: var(--gray-500);
}

.text-small {
    font-size: var(--font-size-sm);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 0.625rem 1.25rem;
    font-size: var(--font-size-sm);
    font-weight: 500;
    line-height: 1.5;
    border: 1px solid transparent;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
}

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

.btn-primary {
    background-color: var(--primary-600);
    color: white;
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--primary-700);
}

.btn-secondary {
    background-color: var(--gray-100);
    color: var(--gray-700);
    border-color: var(--gray-300);
}

.btn-secondary:hover:not(:disabled) {
    background-color: var(--gray-200);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-600);
    border-color: var(--primary-600);
}

.btn-outline:hover:not(:disabled) {
    background-color: var(--primary-50);
}

.btn-danger {
    background-color: var(--danger-500);
    color: white;
    border-color: var(--danger-500);
}

.btn-danger:hover:not(:disabled) {
    background-color: var(--danger-600);
}

.btn-danger-outline {
    background-color: transparent;
    color: var(--danger-500);
    border-color: var(--danger-300);
}

.btn-danger-outline:hover:not(:disabled) {
    background-color: #fee2e2;
    border-color: var(--danger-500);
}

.btn-ghost {
    background-color: transparent;
    color: var(--gray-600);
    border-color: transparent;
}

.btn-ghost:hover:not(:disabled) {
    background-color: var(--gray-100);
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: var(--font-size-base);
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: var(--font-size-xs);
}

.btn-full {
    width: 100%;
}

/* ===== Form Elements ===== */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--gray-700);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.625rem 0.875rem;
    font-size: var(--font-size-base);
    font-family: inherit;
    color: var(--gray-900);
    background-color: white;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-lg);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 3px var(--primary-100);
}

.form-input::placeholder {
    color: var(--gray-400);
}

.form-input.is-invalid {
    border-color: var(--danger-500);
}

.form-input.is-invalid:focus {
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.1);
}

.form-error {
    margin-top: var(--spacing-xs);
    font-size: var(--font-size-sm);
    color: var(--danger-500);
}

.form-hint {
    margin-top: var(--spacing-xs);
    font-size: var(--font-size-sm);
    color: var(--gray-500);
}

.form-checkbox {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.form-checkbox input[type="checkbox"] {
    width: 1rem;
    height: 1rem;
    accent-color: var(--primary-600);
}

/* Input with icon */
.input-group {
    position: relative;
}

.input-group .form-input {
    padding-left: 2.75rem;
}

.input-group-icon {
    position: absolute;
    left: 0.875rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-400);
    pointer-events: none;
}

.input-group-action {
    position: absolute;
    right: 0.5rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--gray-400);
    cursor: pointer;
    padding: 0.25rem;
}

.input-group-action:hover {
    color: var(--gray-600);
}

/* ===== Cards ===== */
.card {
    background-color: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--gray-200);
}

.card-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

.card-body {
    padding: var(--spacing-lg);
}

.card-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid var(--gray-200);
}

/* ===== Alerts ===== */
.alert {
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    font-size: var(--font-size-sm);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
}

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

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

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

.alert-info {
    background-color: #dbeafe;
    color: #1e40af;
    border: 1px solid #bfdbfe;
}

/* ===== Badges ===== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.125rem 0.5rem;
    font-size: var(--font-size-xs);
    font-weight: 500;
    border-radius: var(--radius-full);
}

.badge-primary {
    background-color: var(--primary-100);
    color: var(--primary-700);
}

.badge-success {
    background-color: #dcfce7;
    color: #166534;
}

.badge-warning {
    background-color: #fef3c7;
    color: #92400e;
}

.badge-danger {
    background-color: #fee2e2;
    color: #991b1b;
}

/* ===== Avatar ===== */
.avatar {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    background-color: var(--primary-100);
    color: var(--primary-700);
    font-weight: 600;
    overflow: hidden;
}

.avatar-sm {
    width: 32px;
    height: 32px;
    font-size: var(--font-size-sm);
}

.avatar-md {
    width: 40px;
    height: 40px;
    font-size: var(--font-size-base);
}

.avatar-lg {
    width: 48px;
    height: 48px;
    font-size: var(--font-size-lg);
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* ===== Modal ===== */
.modal-overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    z-index: 5000;
    animation: fadeIn 0.15s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* .modal-content: same card shell (many pages use this instead of .modal) */
.modal,
.modal-content {
    background-color: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--gray-200);
    width: 100%;
    max-width: 560px;
    max-height: 90vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: slideUp 0.2s ease;
}

.modal-content-sm {
    max-width: 440px;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
    background-color: white;
    flex-shrink: 0;
}

.modal-header h3 {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--gray-900);
    margin: 0;
    flex: 1;
    text-align: left;
}

.modal-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border: none;
    background: none;
    color: var(--gray-400);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.modal-close:hover {
    background-color: var(--gray-100);
    color: var(--gray-600);
}

.modal-body {
    padding: var(--spacing-lg);
    overflow-y: auto;
    background-color: white;
    flex: 1;
    min-height: 0;
}

.modal-body p {
    font-size: var(--font-size-sm);
    color: var(--gray-600);
    line-height: 1.6;
    margin: 0 0 var(--spacing-md) 0;
}

.modal-body p:last-child {
    margin-bottom: 0;
}

.modal-body .form-input,
.modal-body select.form-input {
    display: block;
    width: 100%;
    box-sizing: border-box;
    margin-top: var(--spacing-sm);
    padding: 0.625rem 0.75rem;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    background-color: white;
    color: var(--gray-900);
}

.modal-body select.form-input:focus {
    outline: none;
    border-color: var(--primary-400);
    box-shadow: 0 0 0 3px var(--primary-50);
}

.modal-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
}

.modal-icon.danger {
    background-color: #fee2e2;
    color: var(--danger-600);
}

.modal-icon.success {
    background-color: #dcfce7;
    color: var(--success-600);
}

.modal-icon.warning {
    background-color: #fef3c7;
    color: var(--warning-600);
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-lg);
    border-top: 1px solid var(--gray-200);
    background-color: var(--gray-50);
    flex-shrink: 0;
}

/* ===== Divider ===== */
.divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: var(--spacing-lg) 0;
}

.divider::before,
.divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--gray-200);
}

.divider span {
    padding: 0 var(--spacing-md);
    font-size: var(--font-size-sm);
    color: var(--gray-500);
}

/* ===== Loading Spinner ===== */
.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid transparent;
    border-top-color: currentColor;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

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

/* ===== Utilities ===== */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: var(--spacing-xs); }
.gap-2 { gap: var(--spacing-sm); }
.gap-3 { gap: var(--spacing-md); }
.gap-4 { gap: var(--spacing-lg); }

.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.text-center { text-align: center; }
.text-right { text-align: right; }

.w-full { width: 100%; }
.h-full { height: 100%; }

.hidden { display: none; }

/* ===== Blazor Error UI ===== */
#blazor-error-ui {
    background: var(--danger-500);
    color: white;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-md);
    text-align: center;
    display: none;
    z-index: 9999;
}

#blazor-error-ui .reload {
    color: white;
    text-decoration: underline;
    margin-left: var(--spacing-sm);
}

#blazor-error-ui .dismiss {
    cursor: pointer;
    position: absolute;
    right: var(--spacing-md);
}