:root {
    --primary: #0f4c81;
    --primary-dark: #0a3a62;
    --primary-light: #e8f0f8;
    --success: #2e7d32;
    --success-light: #e8f5e9;
    --warning: #ed6c02;
    --warning-light: #fff4e5;
    --gray-50: #f8f9fa;
    --gray-100: #f5f5f5;
    --gray-200: #e0e0e0;
    --gray-300: #cccccc;
    --gray-600: #666666;
    --gray-700: #555555;
    --gray-800: #333333;
    --gray-900: #1a1a1a;
    --border-color: #d9d9d9;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.5;
}

/* Layout */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header - Professional */
.header {
    background: white;
    border-bottom: 1px solid var(--border-color);
    padding: 20px 0;
    margin-bottom: 32px;
}

.header-content {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo h1 {
    font-size: 20px;
    font-weight: 600;
    color: var(--gray-900);
}

.logo p {
    font-size: 12px;
    color: var(--gray-600);
    margin-top: 4px;
}

.nav {
    display: flex;
    gap: 24px;
}

.nav a {
    color: var(--gray-600);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s;
}

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

/* Page Title */
.page-header {
    margin-bottom: 24px;
}

.page-header h2 {
    font-size: 24px;
    font-weight: 600;
    color: var(--gray-900);
}

.page-header p {
    color: var(--gray-600);
    font-size: 14px;
    margin-top: 4px;
}

/* Filters - Clean horizontal bar */
.filters {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 12px 20px;
    margin-bottom: 24px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
}

.filters label {
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-700);
    margin-right: 8px;
}

.filter-btn {
    padding: 6px 16px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--gray-700);
}

.filter-btn i {
    margin-right: 6px;
    font-size: 12px;
}

.filter-btn:hover {
    background: var(--gray-50);
    border-color: var(--primary);
}

.filter-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

/* Items Grid */
.items-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

/* Item Card - Professional card */
.item-card {
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    transition: box-shadow 0.2s, border-color 0.2s;
}

.item-card:hover {
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    border-color: var(--primary);
}

.card-header {
    padding: 16px 20px 12px;
    border-bottom: 1px solid var(--gray-100);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Category Badges - Simple colored tags */
.category-badge {
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.category-badge i {
    margin-right: 4px;
    font-size: 10px;
}

.category-desktop { background: #e8f0f8; color: #0f4c81; }
.category-gpu { background: #f3e5f5; color: #6a1b9a; }
.category-drive { background: #e8f5e9; color: #2e7d32; }
.category-ram { background: #fff8e1; color: #f57c00; }
.category-adapter { background: #e0f2f1; color: #00695c; }

/* Status Badges */
.status-badge {
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 11px;
    font-weight: 600;
}

.status-badge i {
    margin-right: 4px;
    font-size: 10px;
}

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

.status-unavailable {
    background: #fef5f5;
    color: #c62828;
}

/* Card Body */
.card-body {
    padding: 16px 20px;
}

.item-name {
    font-size: 16px;
    font-weight: 500;
    color: var(--gray-900);
    margin-bottom: 8px;
    line-height: 1.4;
}

.item-details {
    color: var(--gray-600);
    font-size: 12px;
}

.item-id {
    font-family: 'SF Mono', Monaco, 'Cascadia Code', monospace;
    background: var(--gray-100);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 11px;
}

/* Card Footer */
.card-footer {
    padding: 12px 20px 16px;
    border-top: 1px solid var(--gray-100);
    background: var(--gray-50);
}

.request-btn {
    width: 100%;
    padding: 8px 16px;
    background: white;
    border: 1px solid var(--primary);
    border-radius: 4px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--primary);
}

.request-btn i {
    margin-right: 6px;
    font-size: 12px;
}

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

.request-btn:disabled {
    background: var(--gray-100);
    border-color: var(--gray-300);
    color: var(--gray-600);
    cursor: not-allowed;
}

/* Modal - Professional dialog */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
}

.modal {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    border-radius: 8px;
    padding: 24px;
    z-index: 1000;
    min-width: 400px;
    max-width: 90%;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.modal h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--gray-900);
}

.modal h3 i {
    margin-right: 8px;
    color: var(--primary);
}

.modal p {
    color: var(--gray-700);
    margin-bottom: 16px;
    font-size: 14px;
}

.modal-item-name {
    color: var(--primary);
    font-weight: 600;
}

.modal-buttons {
    margin-top: 20px;
    display: flex;
    gap: 12px;
    justify-content: flex-end;
}

.modal-buttons button {
    padding: 8px 20px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.modal-buttons button i {
    margin-right: 6px;
}

.cancel-btn {
    background: white;
    border: 1px solid var(--border-color);
    color: var(--gray-700);
}

.cancel-btn:hover {
    background: var(--gray-50);
    border-color: var(--gray-300);
}

.submit-btn {
    background: var(--primary);
    border: 1px solid var(--primary);
    color: white;
}

.submit-btn:hover {
    background: var(--primary-dark);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 60px;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--gray-600);
}

.empty-state i {
    font-size: 48px;
    color: var(--gray-300);
    margin-bottom: 16px;
}

/* Footer */
.footer {
    text-align: center;
    padding: 24px;
    border-top: 1px solid var(--border-color);
    margin-top: 40px;
    color: var(--gray-600);
    font-size: 12px;
    background: white;
}

.item-quantity {
    background: var(--primary-light);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 11px;
    font-weight: 600;
    color: var(--primary);
}

.filter-count {
    font-size: 11px;
    margin-left: 4px;
    opacity: 0.8;
}

.form-group {
    margin: 15px 0;
}

.form-group label {
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-700);
}

.form-group input {
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 6px 10px;
    font-size: 13px;
}

/* Skeleton loading animation */
.skeleton {
    background: linear-gradient(
        90deg,
        var(--gray-100) 25%,
        var(--gray-200) 50%,
        var(--gray-100) 75%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: 4px;
}

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

.skeleton-card .skeleton-title {
    height: 20px;
    width: 80%;
    margin-bottom: 12px;
}

.skeleton-card .skeleton-text {
    height: 14px;
    width: 60%;
    margin-bottom: 8px;
}

.skeleton-card .skeleton-button {
    height: 36px;
    width: 100%;
    margin-top: 12px;
}

/* Hide actual content until loaded */
.items-grid.loaded .item-card {
    display: block;
}

.items-grid.loading .item-card {
    display: none;
}

.items-grid .skeleton-card {
    display: none;
}

.items-grid.loading .skeleton-card {
    display: block;
}