*{margin:0;padding:0;box-sizing:border-box}:root{--primary-color:#2563eb;--primary-hover:#1d4ed8;--success-color:#10b981;--danger-color:#ef4444;--gray-50:#f9fafb;--gray-100:#f3f4f6;--gray-200:#e5e7eb;--gray-300:#d1d5db;--gray-700:#374151;--gray-900:#111827;--border-radius:8px;--shadow:0 1px 3px rgba(0,0,0,0.1);--shadow-lg:0 10px 25px rgba(0,0,0,0.1)}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,sans-serif;line-height:1.6;color:var(--gray-900);background-color:var(--gray-50)}.container{max-width:1200px;margin:0 auto;padding:0 20px}.header{background-color:white;border-bottom:1px solid var(--gray-200);padding:1rem 0;position:-webkit-sticky;position:sticky;top:0;z-index:100;box-shadow:var(--shadow)}.header-content{display:flex;justify-content:space-between;align-items:center}.logo{font-size:1.5rem;font-weight:700;color:var(--primary-color);text-decoration:none}.cart-badge{background-color:var(--primary-color);color:white;padding:.25rem .5rem;border-radius:12px;font-size:.875rem;margin-left:.5rem}.main-content{padding:2rem 0;min-height:calc(100vh - 80px)}.product-card{background:white;box-shadow:var(--shadow-lg);padding:2rem;margin-bottom:2rem}.product-card,.product-image{border-radius:var(--border-radius)}.product-image{width:100%;max-width:450px;height:auto;margin-bottom:1.5rem}.product-title{font-size:2rem;font-weight:700;margin-bottom:.5rem}.product-description{color:var(--gray-700);margin-bottom:1rem;line-height:1.8}.product-meta{gap:1rem;margin-bottom:1.5rem;flex-wrap:wrap}.product-meta,.rating{display:flex;align-items:center}.rating{gap:.25rem}.star{color:#fbbf24}.review-count{color:var(--gray-700);font-size:.875rem}.stock-badge{background-color:var(--success-color);color:white;padding:.25rem .75rem;border-radius:20px;font-size:.875rem}.price-container{margin-bottom:1.5rem}.price-label{font-size:.875rem;color:var(--gray-700);margin-bottom:.25rem}.price{font-size:2.5rem;font-weight:700;color:var(--primary-color)}.price-detail{font-size:.875rem;color:var(--gray-700);margin-top:.25rem}.quantity-selector{display:flex;align-items:center;gap:1rem;margin-bottom:1.5rem}.quantity-button{width:40px;height:40px;border:1px solid var(--gray-300);background:white;border-radius:var(--border-radius);cursor:pointer;font-size:1.25rem;transition:all .2s}.quantity-button:hover:not(:disabled){background-color:var(--gray-100);border-color:var(--primary-color)}.quantity-button:disabled{opacity:.5;cursor:not-allowed}.quantity-display{font-size:1.25rem;min-width:40px}.btn,.quantity-display{font-weight:600;text-align:center}.btn{padding:.75rem 2rem;border:none;border-radius:var(--border-radius);font-size:1rem;cursor:pointer;transition:all .2s;text-decoration:none;display:inline-block}.btn-primary{background-color:var(--primary-color);color:white}.btn-primary:hover:not(:disabled){background-color:var(--primary-hover);box-shadow:var(--shadow-lg)}.btn-primary:disabled{opacity:.5;cursor:not-allowed}.btn-danger{background-color:var(--danger-color);color:white;padding:.5rem 1rem;font-size:.875rem}.btn-danger:hover:not(:disabled){background-color:#dc2626}.btn-block{width:100%;display:block}.cart-section{background:white;border-radius:var(--border-radius);box-shadow:var(--shadow-lg);padding:2rem;margin-bottom:2rem}.section-title{font-size:1.5rem;font-weight:700;margin-bottom:1.5rem;display:flex;align-items:center;gap:.5rem}.cart-empty{text-align:center;padding:3rem;color:var(--gray-700)}.cart-items{display:flex;flex-direction:column;gap:1rem;margin-bottom:1.5rem}.cart-item{display:flex;gap:1rem;padding:1rem;border:1px solid var(--gray-200);align-items:center}.cart-item,.cart-item-image{border-radius:var(--border-radius)}.cart-item-image{width:80px;height:80px;object-fit:cover;flex-shrink:0}.cart-item-details{flex:1 1}.cart-item-name{font-weight:600;margin-bottom:.25rem}.cart-item-price{color:var(--gray-700);font-size:.875rem}.cart-item-quantity{display:flex;align-items:center;gap:.5rem}.cart-item-actions{display:flex;flex-direction:column;gap:.5rem}.cart-summary{border-top:2px solid var(--gray-200);padding-top:1.5rem}.summary-row{display:flex;justify-content:space-between;margin-bottom:.75rem;font-size:1rem}.summary-row.total{font-size:1.5rem;font-weight:700;color:var(--primary-color);margin-top:1rem;padding-top:1rem;border-top:1px solid var(--gray-200)}.checkout-form{background:white;border-radius:var(--border-radius);box-shadow:var(--shadow-lg);padding:2rem}.form-group{margin-bottom:1.5rem}.form-label{display:block;margin-bottom:.5rem;font-weight:600;color:var(--gray-900)}.required{color:var(--danger-color)}.form-input{width:100%;padding:.75rem;border:1px solid var(--gray-300);border-radius:var(--border-radius);font-size:1rem;transition:all .2s}.form-input:focus{outline:none;border-color:var(--primary-color);box-shadow:0 0 0 3px rgba(37,99,235,.1)}.form-input.error{border-color:var(--danger-color)}.error-message{color:var(--danger-color);font-size:.875rem;margin-top:.25rem;display:flex;align-items:center;gap:.25rem}.form-row{display:grid;grid-template-columns:1fr 1fr;grid-gap:1rem;gap:1rem}.success-message{background-color:#d1fae5;border:1px solid var(--success-color);color:#065f46;padding:1rem;border-radius:var(--border-radius);margin-bottom:1.5rem}@media (max-width:768px){.form-row{grid-template-columns:1fr}.cart-item{flex-direction:column;align-items:flex-start}.cart-item-image{width:100%;height:auto}.product-title{font-size:1.5rem}.price{font-size:2rem}}.loading{display:inline-block;width:16px;height:16px;border-radius:50%;border:2px solid rgba(255,255,255,.3);border-top-color:white;animation:spin .6s linear infinite}@keyframes spin{to{transform:rotate(1turn)}}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border-width:0}button:focus-visible,input:focus-visible{outline:2px solid var(--primary-color);outline-offset:2px}