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

    body {
      font-family: 'Montserrat', sans-serif;
      background: #ffffff;
      min-height: 100vh;
    }

    /* Checkout Container */
    .checkout-page {
      max-width: 600px;
      margin: 0 auto;
      padding: 1.5rem;
      background: #ffffff;
    }

    @media (min-width: 768px) {
      .checkout-page {
        max-width: 700px;
        padding: 2rem;
      }
    }

    /* Header */
    .checkout-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 1.5rem;
      padding-bottom: 1rem;
      border-bottom: 1px solid #eaeef2;
    }

    .checkout-logo img {
      height: 60px;
    }

    .back-to-shop {
      color: #1a1a1a;
      text-decoration: none;
      font-size: 0.8rem;
      font-weight: 500;
      display: flex;
      align-items: center;
      gap: 0.4rem;
      transition: color 0.2s;
    }

    .back-to-shop:hover {
      color: #8b7355;
    }

    /* Order Summary Card */
    .order-summary-card {
      background: #fafafa;
      border: 1px solid #f0f0f0;
      border-radius: 16px;
      padding: 1.25rem;
      margin-bottom: 1.5rem;
    }

    .section-title {
      font-size: 0.7rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 2px;
      color: #888;
      margin-bottom: 1rem;
    }

    .order-item {
      display: flex;
      align-items: center;
      gap: 1rem;
      padding-bottom: 1rem;
      border-bottom: 1px solid #ebebeb;
      margin-bottom: 1rem;
    }

    .order-item-img {
      width: 65px;
      height: 65px;
      object-fit: cover;
      border-radius: 10px;
    }

    .order-item-details {
      flex: 1;
    }

    .order-item-name {
      font-size: 0.85rem;
      font-weight: 700;
      color: #1a1a1a;
      margin-bottom: 0.25rem;
    }

    .order-item-size {
      font-size: 0.7rem;
      color: #888;
    }

    .order-item-price {
      font-size: 0.9rem;
      font-weight: 700;
      color: #1a1a1a;
    }

    .order-total {
      display: flex;
      justify-content: space-between;
      font-weight: 700;
      font-size: 1rem;
      color: #1a1a1a;
    }

    /* Form Section */
    .form-section {
      margin-bottom: 1.5rem;
    }

    .form-group {
      margin-bottom: 1rem;
    }

    .form-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0.75rem;
    }

    label {
      display: block;
      font-size: 0.7rem;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: #555;
      margin-bottom: 0.35rem;
    }

    input, select, textarea {
      width: 100%;
      padding: 0.75rem 0.9rem;
      border: 1.5px solid #e5e5e5;
      border-radius: 12px;
      font-family: 'Montserrat', sans-serif;
      font-size: 0.85rem;
      color: #1a1a1a;
      background: #ffffff;
      transition: border-color 0.2s, box-shadow 0.2s;
      outline: none;
    }

    input:focus, select:focus, textarea:focus {
      border-color: #1a1a1a;
      box-shadow: 0 0 0 3px rgba(26,26,26,0.08);
    }

    /* Secure Badge */
    .secure-badge {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      font-size: 0.7rem;
      color: #aaa;
      margin: 1rem 0;
    }

    /* Pay Button - Not the form submit button */
    .pay-btn {
      width: 100%;
      padding: 1rem;
      background: #1a1a1a;
      color: #ffffff;
      border: none;
      border-radius: 14px;
      font-family: 'Montserrat', sans-serif;
      font-size: 0.9rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1.5px;
      cursor: pointer;
      transition: all 0.3s ease;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
    }

    .pay-btn:hover:not(:disabled) {
      background: #000000;
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(0,0,0,0.15);
    }

    .pay-btn:disabled {
      background: #cccccc;
      cursor: not-allowed;
    }

    /* Empty Cart */
    .empty-cart {
      text-align: center;
      padding: 3rem 1.5rem;
    }

    .empty-cart svg {
      width: 70px;
      height: 70px;
      color: #ccc;
      margin-bottom: 1rem;
    }

    .empty-cart h3 {
      font-size: 1.2rem;
      margin-bottom: 0.5rem;
    }

    .empty-cart p {
      color: #888;
      margin-bottom: 1.5rem;
    }

    .shop-again-btn {
      display: inline-block;
      padding: 0.8rem 2rem;
      background: #1a1a1a;
      color: white;
      text-decoration: none;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.8rem;
    }

    /* Error Toast */
    .error-toast {
      position: fixed;
      bottom: 20px;
      left: 20px;
      right: 20px;
      background: #c0392b;
      color: white;
      padding: 12px 20px;
      border-radius: 12px;
      font-size: 0.8rem;
      font-weight: 500;
      text-align: center;
      z-index: 1000;
      animation: slideUp 0.3s ease;
    }

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

    @media (min-width: 768px) {
      .error-toast {
        left: auto;
        right: 20px;
        max-width: 350px;
      }
    }

    /* Loading Spinner */
    .spinner {
      display: inline-block;
      width: 16px;
      height: 16px;
      border: 2px solid rgba(255,255,255,0.3);
      border-radius: 50%;
      border-top-color: white;
      animation: spin 0.6s linear infinite;
    }

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

    /* Hidden iframe for form submission */
    .hidden-iframe {
      display: none;
    }