/**
 * Premium World-Class UX Enhancements
 * ThinQShopping - Mobile-First Design System
 * Clean, Flat, Professional - NO SHADOWS, NO GRADIENTS
 */

/* ============================================
   DESIGN TOKENS - World-Class System
   ============================================ */

:root {
    /* Brand Colors - Enhanced Palette */
    --primary: #0e2945;
    --primary-dark: #0a1f35;
    --primary-light: #1a3a5a;
    --primary-lighter: #e8eef5;
    --primary-lightest: #f5f8fb;

    /* Neutral Palette - Professional */
    --neutral-900: #0f172a;
    --neutral-800: #1e293b;
    --neutral-700: #334155;
    --neutral-600: #475569;
    --neutral-500: #64748b;
    --neutral-400: #94a3b8;
    --neutral-300: #cbd5e1;
    --neutral-200: #e2e8f0;
    --neutral-100: #f1f5f9;
    --neutral-50: #f8fafc;
    --white: #ffffff;

    /* Semantic Colors - Clear Meaning */
    --success: #10b981;
    --success-light: #d1fae5;
    --error: #ef4444;
    --error-light: #fee2e2;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --info: #3b82f6;
    --info-light: #dbeafe;

    /* Typography Scale - Perfect Hierarchy */
    --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-family-display: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

    --font-size-xs: 0.6875rem;
    /* 11px */
    --font-size-sm: 0.8125rem;
    /* 13px */
    --font-size-base: 0.875rem;
    /* 14px */
    --font-size-lg: 1rem;
    /* 16px */
    --font-size-xl: 1.125rem;
    /* 18px */
    --font-size-2xl: 1.25rem;
    /* 20px */
    --font-size-3xl: 1.5rem;
    /* 24px */
    --font-size-4xl: 1.875rem;
    /* 30px */

    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;

    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;

    /* Spacing Scale - Consistent Rhythm */
    --space-1: 0.25rem;
    /* 4px */
    --space-2: 0.5rem;
    /* 8px */
    --space-3: 0.75rem;
    /* 12px */
    --space-4: 1rem;
    /* 16px */
    --space-5: 1.25rem;
    /* 20px */
    --space-6: 1.5rem;
    /* 24px */
    --space-8: 2rem;
    /* 32px */
    --space-10: 2.5rem;
    /* 40px */
    --space-12: 3rem;
    /* 48px */
    --space-16: 4rem;
    /* 64px */

    /* Border Radius - Modern Curves */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 24px;
    --radius-full: 9999px;

    /* Transitions - Smooth & Fast */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);

    /* Touch Targets - iOS Standards */
    --touch-min: 44px;
    --touch-comfortable: 48px;
    --touch-large: 56px;

    /* Z-Index Scale - Layering System */
    --z-base: 0;
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;
}

/* ============================================
   PREMIUM BUTTON SYSTEM
   ============================================ */

.btn-premium {
    /* Base Styles */
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);

    /* Typography */
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    line-height: var(--line-height-tight);
    text-decoration: none;
    white-space: nowrap;

    /* Spacing */
    padding: var(--space-3) var(--space-6);
    min-height: var(--touch-comfortable);

    /* Visual */
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;

    /* Transitions */
    transition: all var(--transition-base);

    /* Touch */
    -webkit-tap-highlight-color: transparent;
    user-select: none;
}

/* Primary Button */
.btn-premium-primary {
    background-color: var(--primary);
    color: var(--white);
    border-color: var(--primary);
}

.btn-premium-primary:hover {
    background-color: var(--primary-dark);
    border-color: var(--primary-dark);
    color: var(--white);
}

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

/* Secondary Button */
.btn-premium-secondary {
    background-color: transparent;
    color: var(--primary);
    border-color: var(--primary);
}

.btn-premium-secondary:hover {
    background-color: var(--primary-lightest);
    color: var(--primary-dark);
}

/* Ghost Button */
.btn-premium-ghost {
    background-color: transparent;
    color: var(--neutral-700);
    border-color: transparent;
}

.btn-premium-ghost:hover {
    background-color: var(--neutral-100);
    color: var(--neutral-900);
}

/* Button Sizes */
.btn-premium-sm {
    padding: var(--space-2) var(--space-4);
    font-size: var(--font-size-sm);
    min-height: var(--touch-min);
}

.btn-premium-lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--font-size-lg);
    min-height: var(--touch-large);
}

/* Button States */
.btn-premium:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

.btn-premium-loading {
    position: relative;
    color: transparent;
    pointer-events: none;
}

.btn-premium-loading::after {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    top: 50%;
    left: 50%;
    margin-left: -8px;
    margin-top: -8px;
    border: 2px solid currentColor;
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 0.6s linear infinite;
}

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

/* ============================================
   PREMIUM INPUT SYSTEM
   ============================================ */

.input-premium {
    /* Base Styles */
    width: 100%;
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-normal);
    color: var(--neutral-900);

    /* Spacing */
    padding: var(--space-3) var(--space-4);
    min-height: var(--touch-comfortable);

    /* Visual */
    background-color: var(--white);
    border: 2px solid var(--neutral-300);
    border-radius: var(--radius-md);

    /* Transitions */
    transition: all var(--transition-base);

    /* Remove default styles */
    outline: none;
    appearance: none;
}

.input-premium::placeholder {
    color: var(--neutral-400);
}

.input-premium:hover {
    border-color: var(--neutral-400);
}

.input-premium:focus {
    border-color: var(--primary);
    background-color: var(--white);
}

.input-premium:disabled {
    background-color: var(--neutral-100);
    color: var(--neutral-500);
    cursor: not-allowed;
}

/* Input States */
.input-premium-error {
    border-color: var(--error);
}

.input-premium-error:focus {
    border-color: var(--error);
}

.input-premium-success {
    border-color: var(--success);
}

/* Input Group */
.input-group-premium {
    position: relative;
    width: 100%;
}

.input-group-premium .input-icon {
    position: absolute;
    left: var(--space-4);
    top: 50%;
    transform: translateY(-50%);
    color: var(--neutral-400);
    pointer-events: none;
}

.input-group-premium .input-premium {
    padding-left: var(--space-12);
}

/* ============================================
   PREMIUM CARD SYSTEM
   ============================================ */

.card-premium {
    background-color: var(--white);
    border: 1px solid var(--neutral-200);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    transition: all var(--transition-base);
}

.card-premium:hover {
    border-color: var(--primary);
}

.card-premium-interactive {
    cursor: pointer;
}

.card-premium-interactive:active {
    transform: scale(0.99);
}

/* Card Header */
.card-premium-header {
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-4);
    border-bottom: 1px solid var(--neutral-200);
}

.card-premium-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--neutral-900);
    margin: 0;
}

.card-premium-subtitle {
    font-size: var(--font-size-sm);
    color: var(--neutral-600);
    margin: var(--space-1) 0 0 0;
}

/* Card Body */
.card-premium-body {
    color: var(--neutral-700);
    line-height: var(--line-height-relaxed);
}

/* Card Footer */
.card-premium-footer {
    margin-top: var(--space-4);
    padding-top: var(--space-4);
    border-top: 1px solid var(--neutral-200);
    display: flex;
    gap: var(--space-3);
    align-items: center;
}

/* ============================================
   PREMIUM BADGE SYSTEM
   ============================================ */

.badge-premium {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-1) var(--space-3);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    line-height: 1;
    border-radius: var(--radius-full);
    white-space: nowrap;
}

.badge-premium-primary {
    background-color: var(--primary-lighter);
    color: var(--primary);
}

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

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

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

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

/* ============================================
   PREMIUM ALERT SYSTEM
   ============================================ */

.alert-premium {
    padding: var(--space-4);
    border-radius: var(--radius-md);
    border-left: 4px solid;
    display: flex;
    gap: var(--space-3);
    align-items: flex-start;
}

.alert-premium-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
}

.alert-premium-content {
    flex: 1;
}

.alert-premium-title {
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--space-1);
}

.alert-premium-message {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-relaxed);
}

.alert-premium-success {
    background-color: var(--success-light);
    border-color: var(--success);
    color: var(--success);
}

.alert-premium-error {
    background-color: var(--error-light);
    border-color: var(--error);
    color: var(--error);
}

.alert-premium-warning {
    background-color: var(--warning-light);
    border-color: var(--warning);
    color: var(--warning);
}

.alert-premium-info {
    background-color: var(--info-light);
    border-color: var(--info);
    color: var(--info);
}

/* ============================================
   PREMIUM SKELETON LOADING
   ============================================ */

.skeleton-premium {
    background-color: var(--neutral-200);
    border-radius: var(--radius-md);
    position: relative;
    overflow: hidden;
}

.skeleton-premium::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    transform: translateX(-100%);
    background: linear-gradient(90deg,
            transparent 0%,
            rgba(255, 255, 255, 0.6) 50%,
            transparent 100%);
    animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
    100% {
        transform: translateX(100%);
    }
}

.skeleton-premium-text {
    height: 1rem;
    margin-bottom: var(--space-2);
}

.skeleton-premium-title {
    height: 1.5rem;
    width: 60%;
    margin-bottom: var(--space-3);
}

.skeleton-premium-avatar {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
}

.skeleton-premium-image {
    width: 100%;
    aspect-ratio: 16 / 9;
}

/* ============================================
   PREMIUM EMPTY STATE
   ============================================ */

.empty-state-premium {
    text-align: center;
    padding: var(--space-12) var(--space-6);
}

.empty-state-premium-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--space-4);
    color: var(--neutral-400);
}

.empty-state-premium-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--neutral-900);
    margin-bottom: var(--space-2);
}

.empty-state-premium-message {
    font-size: var(--font-size-base);
    color: var(--neutral-600);
    line-height: var(--line-height-relaxed);
    max-width: 400px;
    margin: 0 auto var(--space-6);
}

/* ============================================
   PREMIUM MICRO-INTERACTIONS
   ============================================ */

/* Smooth Focus Rings */
*:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

/* Touch Feedback */
.touch-feedback {
    position: relative;
    overflow: hidden;
}

.touch-feedback::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.3s, height 0.3s;
}

.touch-feedback:active::after {
    width: 200px;
    height: 200px;
}

/* Smooth Hover States */
.hover-lift {
    transition: transform var(--transition-base);
}

.hover-lift:hover {
    transform: translateY(-2px);
}

/* ============================================
   PREMIUM TYPOGRAPHY
   ============================================ */

.heading-premium-1 {
    font-size: var(--font-size-4xl);
    font-weight: var(--font-weight-extrabold);
    line-height: var(--line-height-tight);
    color: var(--neutral-900);
    letter-spacing: -0.02em;
}

.heading-premium-2 {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--neutral-900);
    letter-spacing: -0.01em;
}

.heading-premium-3 {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--neutral-900);
}

.heading-premium-4 {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-semibold);
    line-height: var(--line-height-normal);
    color: var(--neutral-900);
}

.text-premium-lead {
    font-size: var(--font-size-lg);
    line-height: var(--line-height-relaxed);
    color: var(--neutral-700);
}

.text-premium-body {
    font-size: var(--font-size-base);
    line-height: var(--line-height-relaxed);
    color: var(--neutral-700);
}

.text-premium-small {
    font-size: var(--font-size-sm);
    line-height: var(--line-height-normal);
    color: var(--neutral-600);
}

.text-premium-xs {
    font-size: var(--font-size-xs);
    line-height: var(--line-height-normal);
    color: var(--neutral-500);
}

/* ============================================
   RESPONSIVE UTILITIES
   ============================================ */

@media (max-width: 767px) {
    :root {
        --font-size-4xl: 1.875rem;
        /* 30px on mobile */
        --font-size-3xl: 1.5rem;
        /* 24px on mobile */
    }

    .card-premium {
        padding: var(--space-4);
    }

    .empty-state-premium {
        padding: var(--space-8) var(--space-4);
    }
}

/* ============================================
   ACCESSIBILITY ENHANCEMENTS
   ============================================ */

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* High Contrast Mode */
@media (prefers-contrast: high) {
    .btn-premium {
        border-width: 3px;
    }

    .input-premium {
        border-width: 3px;
    }
}

/* Dark Mode Support (Optional) */
@media (prefers-color-scheme: dark) {
    :root {
        --neutral-900: #f8fafc;
        --neutral-800: #f1f5f9;
        --neutral-700: #e2e8f0;
        --neutral-600: #cbd5e1;
        --neutral-500: #94a3b8;
        --neutral-400: #64748b;
        --neutral-300: #475569;
        --neutral-200: #334155;
        --neutral-100: #1e293b;
        --neutral-50: #0f172a;
        --white: #0f172a;
    }
}

/* ============================================
   WORLD-CLASS SHOP GRID
   ============================================ */
.products-grid {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: repeat(2, 1fr);
    /* 2 cols mobile */
    padding: 1rem 0;
}

@media (min-width: 768px) {
    .products-grid {
        grid-template-columns: repeat(3, 1fr);
        /* 3 cols tablet */
        gap: 2rem;
    }
}

@media (min-width: 1200px) {
    .products-grid {
        grid-template-columns: repeat(4, 1fr);
        /* 4-5 cols desktop */
    }
}

/* Premium Product Card Refinements */
.product-card-premium {
    border: 1px solid var(--neutral-200);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--white);
    transition: transform var(--transition-base);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.product-card-premium:hover {
    transform: translateY(-8px);
    border-color: var(--primary);
}

.product-card-premium .img-wrapper {
    aspect-ratio: 1/1;
    background: var(--neutral-50);
    padding: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-card-premium .img-wrapper img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.product-card-premium-body {
    padding: 1.25rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.product-title-premium {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    color: var(--neutral-900);
    margin-bottom: 0.5rem;
    line-height: var(--line-height-tight);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.product-price-premium {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: var(--primary);
    margin-top: auto;
}

/* ============================================
   PREMIUM CHECKOUT FLOW
   ============================================ */
.checkout-wrapper-premium {
    background: var(--white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--neutral-200);
    padding: var(--space-8);
    margin-top: var(--space-8);
}

.checkout-step-premium {
    display: flex;
    flex-direction: column;
    gap: var(--space-6);
    margin-bottom: var(--space-10);
}

.checkout-step-item {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding-bottom: var(--space-4);
    border-bottom: 2px solid var(--neutral-100);
}

.step-badge-premium {
    width: 32px;
    height: 32px;
    background: var(--primary);
    color: #fff;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-sm);
}

.step-title-premium {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--neutral-900);
}

.checkout-summary-premium {
    background: var(--neutral-50);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    position: sticky;
    top: 100px;
}