/* ============================================
   MODERN DESIGN SYSTEM - Feedback USSD Platform
   ============================================ */

/* === COLOR PALETTE === */
:root {
    /* Primary Colors - Modern Blue/Purple Gradient */
    --primary-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
    --primary-600: #6366f1;
    --primary-700: #4f46e5;
    --primary-800: #4338ca;
    
    /* Accent Colors */
    --accent-purple: #8b5cf6;
    --accent-pink: #d946ef;
    --accent-cyan: #06b6d4;
    
    /* 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: #10b981;
    --success-light: #d1fae5;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --error: #ef4444;
    --error-light: #fee2e2;
    --info: #3b82f6;
    --info-light: #dbeafe;
    
    /* Typography */
    --font-display: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-mono: 'SF Mono', 'Monaco', 'Cascadia Code', 'Courier New', monospace;
    
    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* Shadows */
    --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);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --shadow-glow: 0 0 30px rgba(99, 102, 241, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* === RESET & BASE === */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-800);
    background: var(--gray-50);
    min-height: 100vh;
}

/* === TYPOGRAPHY === */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.2;
    color: var(--gray-900);
    margin-bottom: var(--space-md);
}

h1 {
    font-size: 2.5rem;
    letter-spacing: -0.02em;
}

h2 {
    font-size: 2rem;
    letter-spacing: -0.01em;
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

p {
    margin-bottom: var(--space-md);
}

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

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

/* === LAYOUT === */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.container-sm {
    max-width: 640px;
}

.container-md {
    max-width: 960px;
}

.section {
    padding: var(--space-3xl) 0;
}

/* === GRADIENT BACKGROUNDS === */
.bg-gradient-primary {
    background: var(--primary-gradient);
}

.bg-gradient-purple {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.bg-gradient-blue {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

.bg-gradient-sunset {
    background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
}

/* === GLASS MORPHISM === */
.glass {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.glass-dark {
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* === CARDS === */
.card {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid var(--gray-200);
}

.card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.card-header {
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-lg);
    border-bottom: 2px solid var(--gray-100);
}

.card-body {
    margin-bottom: var(--space-lg);
}

.card-footer {
    padding-top: var(--space-lg);
    border-top: 2px solid var(--gray-100);
}

/* === BUTTONS === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: var(--font-display);
    border-radius: var(--radius-lg);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.btn:before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width var(--transition-slow), height var(--transition-slow);
}

.btn:hover:before {
    width: 300px;
    height: 300px;
}

.btn:active {
    transform: scale(0.98);
}

.btn-primary {
    background: var(--primary-gradient);
    color: white;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
    transform: translateY(-2px);
}

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

.btn-secondary:hover {
    background: var(--gray-200);
}

.btn-success {
    background: linear-gradient(135deg, var(--success) 0%, #059669 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

.btn-danger {
    background: linear-gradient(135deg, var(--error) 0%, #dc2626 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(239, 68, 68, 0.3);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary-600);
    color: var(--primary-600);
}

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

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-icon {
    padding: 0.75rem;
    aspect-ratio: 1;
}

.btn-group {
    display: flex;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

/* === FORMS === */
.form-group {
    margin-bottom: var(--space-lg);
}

.form-label {
    display: block;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: var(--space-sm);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.form-control {
    width: 100%;
    padding: 0.875rem 1rem;
    font-size: 1rem;
    font-family: var(--font-body);
    color: var(--gray-900);
    background: white;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    outline: none;
}

.form-control:focus {
    border-color: var(--primary-600);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

textarea.form-control {
    resize: vertical;
    min-height: 120px;
}

select.form-control {
    appearance: none;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
    background-position: right 0.75rem center;
    background-repeat: no-repeat;
    background-size: 1.5em 1.5em;
    padding-right: 3rem;
}

.form-control.is-invalid {
    border-color: var(--error);
}

.form-control.is-valid {
    border-color: var(--success);
}

.form-text {
    display: block;
    margin-top: var(--space-sm);
    font-size: 0.875rem;
    color: var(--gray-500);
}

.form-error {
    color: var(--error);
    font-size: 0.875rem;
    margin-top: var(--space-sm);
}

/* === RADIO & CHECKBOX === */
.form-check {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-md);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-bottom: var(--space-sm);
}

.form-check:hover {
    border-color: var(--primary-600);
    background: var(--gray-50);
}

.form-check input[type="radio"],
.form-check input[type="checkbox"] {
    width: 1.25rem;
    height: 1.25rem;
    cursor: pointer;
    accent-color: var(--primary-600);
}

.form-check-label {
    flex: 1;
    cursor: pointer;
    font-weight: 500;
}

.form-check input:checked + .form-check-label {
    color: var(--primary-600);
}

/* === ALERTS === */
.alert {
    padding: var(--space-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-lg);
    display: flex;
    align-items: start;
    gap: var(--space-md);
    border-left: 4px solid;
    animation: slideInDown var(--transition-base);
}

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

.alert-icon {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.alert-content {
    flex: 1;
}

.alert-title {
    font-weight: 600;
    margin-bottom: var(--space-xs);
}

.alert-success {
    background: var(--success-light);
    border-color: var(--success);
    color: #065f46;
}

.alert-error {
    background: var(--error-light);
    border-color: var(--error);
    color: #991b1b;
}

.alert-warning {
    background: var(--warning-light);
    border-color: var(--warning);
    color: #92400e;
}

.alert-info {
    background: var(--info-light);
    border-color: var(--info);
    color: #1e40af;
}

/* === BADGES === */
.badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-xs);
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-radius: var(--radius-full);
}

.badge-success {
    background: var(--success-light);
    color: var(--success);
}

.badge-warning {
    background: var(--warning-light);
    color: var(--warning);
}

.badge-error {
    background: var(--error-light);
    color: var(--error);
}

.badge-info {
    background: var(--info-light);
    color: var(--info);
}

.badge-primary {
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary-600);
}

/* === PROGRESS BAR === */
.progress {
    width: 100%;
    height: 0.75rem;
    background: var(--gray-200);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background: var(--primary-gradient);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
    animation: shimmer 2s infinite;
    background-size: 200% 100%;
}

@keyframes shimmer {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* === TABLES === */
.table-container {
    overflow-x: auto;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
}

.table {
    width: 100%;
    border-collapse: collapse;
    background: white;
}

.table thead {
    background: var(--gray-50);
}

.table th {
    padding: var(--space-md);
    text-align: left;
    font-weight: 600;
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--gray-600);
    border-bottom: 2px solid var(--gray-200);
}

.table td {
    padding: var(--space-md);
    border-bottom: 1px solid var(--gray-100);
}

.table tbody tr {
    transition: background var(--transition-fast);
}

.table tbody tr:hover {
    background: var(--gray-50);
}

/* === PAGINATION === */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    margin: var(--space-xl) 0;
    flex-wrap: wrap;
}

.page-link {
    min-width: 2.5rem;
    height: 2.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0 var(--space-sm);
    border: 2px solid var(--gray-200);
    border-radius: var(--radius-md);
    background: white;
    color: var(--gray-700);
    font-weight: 500;
    text-decoration: none;
    transition: all var(--transition-fast);
}

.page-link:hover:not(.disabled):not(.active) {
    border-color: var(--primary-600);
    background: var(--gray-50);
}

.page-link.active {
    background: var(--primary-gradient);
    color: white;
    border-color: transparent;
    box-shadow: var(--shadow-glow);
}

.page-link.disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* === LOADING SPINNER === */
.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--gray-200);
    border-top-color: var(--primary-600);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.spinner-sm {
    width: 20px;
    height: 20px;
    border-width: 2px;
}

.spinner-lg {
    width: 60px;
    height: 60px;
    border-width: 6px;
}

/* === MODAL === */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: var(--space-lg);
    animation: fadeIn var(--transition-base);
}

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

.modal-content {
    background: white;
    border-radius: var(--radius-2xl);
    max-width: 600px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-2xl);
    animation: scaleIn var(--transition-base);
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.modal-header {
    padding: var(--space-xl);
    border-bottom: 2px solid var(--gray-100);
}

.modal-body {
    padding: var(--space-xl);
}

.modal-footer {
    padding: var(--space-xl);
    border-top: 2px solid var(--gray-100);
    display: flex;
    gap: var(--space-md);
    justify-content: flex-end;
}

/* === UTILITIES === */
.text-center {
    text-align: center;
}

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

.flex {
    display: flex;
}

.flex-column {
    flex-direction: column;
}

.items-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.gap-sm {
    gap: var(--space-sm);
}

.gap-md {
    gap: var(--space-md);
}

.gap-lg {
    gap: var(--space-lg);
}

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--space-sm); }
.mt-2 { margin-top: var(--space-md); }
.mt-3 { margin-top: var(--space-lg); }
.mt-4 { margin-top: var(--space-xl); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--space-sm); }
.mb-2 { margin-bottom: var(--space-md); }
.mb-3 { margin-bottom: var(--space-lg); }
.mb-4 { margin-bottom: var(--space-xl); }

.p-0 { padding: 0; }
.p-1 { padding: var(--space-sm); }
.p-2 { padding: var(--space-md); }
.p-3 { padding: var(--space-lg); }
.p-4 { padding: var(--space-xl); }

/* === RESPONSIVE === */
@media (max-width: 768px) {
    :root {
        font-size: 14px;
    }
    
    h1 {
        font-size: 2rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    .btn-group {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
    }
}

/* === ANIMATIONS === */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fadeInUp {
    animation: fadeInUp var(--transition-slow) ease-out;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* === DARK MODE SUPPORT === */
@media (prefers-color-scheme: dark) {
    .auto-dark {
        background: var(--gray-900);
        color: var(--gray-100);
    }
    
    .auto-dark .card {
        background: var(--gray-800);
        border-color: var(--gray-700);
    }
    
    .auto-dark .form-control {
        background: var(--gray-800);
        border-color: var(--gray-700);
        color: var(--gray-100);
    }
}