/**
 * Price Comparison Platform - Design System
 * Clean, Clear, Modern UI
 * Font: Inter
 * Primary Color: #1F7DFF (Trust Blue)
 */

/* ========================================
   CSS Variables - Design System
   ======================================== */
:root {
    /* Primary Colors */
    --primary-blue: #1F7DFF;
    --secondary-blue: #0D47A1;
    --light-blue: #E3F2FD;

    /* Accent Colors */
    --success-green: #10B981;
    --warning-orange: #F97316;
    --danger-red: #EF4444;

    /* Neutral Colors */
    --dark-gray: #1F2937;
    --medium-gray: #6B7280;
    --light-gray: #E5E7EB;
    --very-light-gray: #F9FAFB;
    --white: #FFFFFF;

    /* Special Highlights */
    --best-price-bg: #F0FDF4;
    --best-price-border: #10B981;
    --price-drop-bg: #FEF3C7;
    --price-drop-border: #FBBF24;

    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    /* Spacing (4px base unit) */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 12px;
    --space-lg: 16px;
    --space-xl: 24px;
    --space-2xl: 32px;
    --space-3xl: 48px;

    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.12);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.16);

    /* Transitions */
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ========================================
   Base Styles
   ======================================== */
body {
    font-family: var(--font-family);
    font-size: 14px;
    line-height: 1.6;
    color: var(--dark-gray);
    background-color: var(--very-light-gray);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

@media (min-width: 640px) {
    .container { padding: 0 var(--space-xl); }
}

@media (min-width: 1024px) {
    .container { padding: 0 var(--space-2xl); }
}

.main-content {
    min-height: calc(100vh - 200px);
    padding: var(--space-xl) 0;
}

/* ========================================
   Typography
   ======================================== */
h1 { font-size: 32px; font-weight: 700; line-height: 1.2; margin-bottom: var(--space-lg); }
h2 { font-size: 24px; font-weight: 700; line-height: 1.3; margin-bottom: var(--space-md); }
h3 { font-size: 20px; font-weight: 600; line-height: 1.4; margin-bottom: var(--space-md); }

.text-large { font-size: 16px; }
.text-regular { font-size: 14px; }
.text-small { font-size: 12px; }

.text-muted { color: var(--medium-gray); }
.text-primary { color: var(--primary-blue); }
.text-success { color: var(--success-green); }
.text-danger { color: var(--danger-red); }

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-block;
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 600;
    line-height: 1.5;
    text-align: center;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary {
    background-color: var(--primary-blue);
    color: var(--white);
    box-shadow: 0 2px 4px rgba(31, 125, 255, 0.25);
}

.btn-primary:hover {
    background-color: var(--secondary-blue);
    box-shadow: 0 4px 8px rgba(31, 125, 255, 0.35);
}

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

.btn-secondary {
    background-color: var(--very-light-gray);
    color: var(--dark-gray);
    border: 1px solid var(--light-gray);
}

.btn-secondary:hover {
    background-color: #F3F4F6;
}

.btn-success {
    background-color: var(--success-green);
    color: var(--white);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 12px;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 16px;
}

/* ========================================
   Cards
   ======================================== */
.card {
    background: var(--white);
    border: 1px solid var(--light-gray);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.product-card {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.product-card-image {
    width: 100%;
    height: 200px;
    object-fit: contain;
    padding: var(--space-md);
    background: var(--very-light-gray);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-md);
}

.product-card-title {
    font-size: 14px;
    font-weight: 600;
    color: var(--dark-gray);
    margin-bottom: var(--space-sm);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.product-card-brand {
    font-size: 12px;
    color: var(--medium-gray);
    margin-bottom: var(--space-sm);
}

.product-card-price {
    font-size: 18px;
    font-weight: 700;
    color: var(--dark-gray);
    margin-bottom: var(--space-xs);
}

.product-card-original-price {
    font-size: 14px;
    color: var(--medium-gray);
    text-decoration: line-through;
    margin-right: var(--space-sm);
}

.product-card-discount {
    font-size: 12px;
    font-weight: 600;
    color: var(--success-green);
}

.product-card-footer {
    margin-top: auto;
    padding-top: var(--space-md);
}

/* ========================================
   Badges
   ======================================== */
.badge {
    display: inline-block;
    padding: 4px 8px;
    font-size: 11px;
    font-weight: 600;
    border-radius: var(--radius-sm);
}

.badge-price-drop {
    background: var(--price-drop-bg);
    color: #92400E;
    border: 1px solid var(--price-drop-border);
}

.badge-best-price {
    background: #DBEAFE;
    color: #0C4A6E;
    border: 1px solid #0EA5E9;
}

.badge-in-stock {
    background: var(--best-price-bg);
    color: #166534;
    border: 1px solid #86EFAC;
}

.badge-out-of-stock {
    background: #FEE2E2;
    color: #991B1B;
    border: 1px solid #FCA5A5;
}

.badge-trending {
    background: #FEF3C7;
    color: #92400E;
    border: 1px solid #FBBF24;
}

/* ========================================
   Price Comparison Table
   ======================================== */
.price-table {
    width: 100%;
    background: var(--white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.price-table-header {
    background: #F3F4F6;
    padding: 12px 16px;
    font-weight: 600;
    font-size: 14px;
    border-bottom: 1px solid var(--light-gray);
}

.price-table-row {
    padding: 12px 16px;
    border-bottom: 1px solid var(--light-gray);
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: var(--transition);
}

.price-table-row:hover {
    background: #FAFBFC;
}

.price-table-row-best {
    background: var(--best-price-bg);
    border-left: 4px solid var(--best-price-border);
}

.price-table-source {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.price-table-logo {
    width: 60px;
    height: 30px;
    object-fit: contain;
}

.price-table-price {
    font-size: 18px;
    font-weight: 700;
    color: var(--dark-gray);
}

/* ========================================
   Filter Sidebar
   ======================================== */
.filter-sidebar {
    background: var(--very-light-gray);
    border: 1px solid var(--light-gray);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
}

.filter-group {
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-lg);
    border-bottom: 1px solid var(--light-gray);
}

.filter-group:last-child {
    border-bottom: none;
    margin-bottom: 0;
    padding-bottom: 0;
}

.filter-title {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: var(--space-md);
    color: var(--dark-gray);
}

.filter-checkbox {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-sm);
    cursor: pointer;
}

.filter-checkbox input[type="checkbox"] {
    width: 16px;
    height: 16px;
    accent-color: var(--primary-blue);
}

.filter-checkbox label {
    font-size: 14px;
    color: var(--dark-gray);
    cursor: pointer;
}

.filter-range {
    display: flex;
    gap: var(--space-sm);
    align-items: center;
}

.filter-input {
    flex: 1;
    padding: 8px 12px;
    border: 1px solid var(--light-gray);
    border-radius: var(--radius-md);
    font-size: 14px;
}

.filter-input:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(31, 125, 255, 0.1);
}

/* ========================================
   Grid Layouts
   ======================================== */
.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: var(--space-xl);
    margin-top: var(--space-xl);
}

@media (max-width: 640px) {
    .product-grid {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
}

.two-column-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--space-xl);
    margin-top: var(--space-xl);
}

@media (max-width: 1024px) {
    .two-column-layout {
        grid-template-columns: 1fr;
    }
}

/* ========================================
   Product Detail Page
   ======================================== */
.product-detail {
    background: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    box-shadow: var(--shadow-sm);
}

.product-detail-header {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: var(--space-2xl);
    margin-bottom: var(--space-2xl);
}

@media (max-width: 1024px) {
    .product-detail-header {
        grid-template-columns: 1fr;
    }
}

.product-image-gallery {
    background: var(--very-light-gray);
    border-radius: var(--radius-lg);
    padding: var(--space-xl);
    text-align: center;
}

.product-main-image {
    width: 100%;
    max-height: 400px;
    object-fit: contain;
}

.product-info h1 {
    font-size: 28px;
    margin-bottom: var(--space-sm);
}

.product-brand {
    font-size: 16px;
    color: var(--medium-gray);
    margin-bottom: var(--space-lg);
}

.product-rating {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.product-rating-stars {
    color: #FBBF24;
    font-size: 18px;
}

.product-rating-count {
    font-size: 14px;
    color: var(--medium-gray);
}

.product-price-summary {
    background: var(--very-light-gray);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    margin-bottom: var(--space-lg);
}

.product-price-label {
    font-size: 14px;
    color: var(--medium-gray);
    margin-bottom: var(--space-xs);
}

.product-price-value {
    font-size: 32px;
    font-weight: 700;
    color: var(--dark-gray);
}

.product-price-range {
    font-size: 14px;
    color: var(--medium-gray);
    margin-top: var(--space-xs);
}

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

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: var(--space-sm);
    color: var(--dark-gray);
}

.form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 10px 12px;
    font-size: 14px;
    border: 1px solid var(--light-gray);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(31, 125, 255, 0.1);
}

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

.form-help {
    font-size: 12px;
    color: var(--medium-gray);
    margin-top: var(--space-xs);
}

.form-error {
    font-size: 12px;
    color: var(--danger-red);
    margin-top: var(--space-xs);
}

/* Footer styles moved to shared include: includes/footer_styles.html */

/* ========================================
   Utility Classes
   ======================================== */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }

.mt-xs { margin-top: var(--space-xs); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-xs { margin-bottom: var(--space-xs); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

.d-flex { display: flex; }
.align-items-center { align-items: center; }
.justify-content-between { justify-content: space-between; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }