/* ==================== MAIN CONTAINER ==================== */
    .main-container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 40px 20px;
    }

    .payment-container {
      max-width: 500px;
      margin: 0 auto;
    }

    /* ==================== SECTION STYLES ==================== */
    .payment-section {
      background: white;
      border-radius: 12px;
      padding: 30px;
      box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    }

    .section-title {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary-color);
      margin-bottom: 8px;
    }

    .section-subtitle {
      color: var(--text-light);
      margin-bottom: 24px;
      font-size: 15px;
    }

    /* ==================== FLOATING INPUTS ==================== */
    .floating-input {
      position: relative;
      margin-bottom: 28px;
    }

    .floating-input__field {
      width: 100%;
      padding: 12px 0 8px;
      border: none;
      border-bottom: 2px solid var(--border-color);
      background: transparent;
      font-size: 16px;
      color: var(--text-dark);
      transition: all var(--transition-speed) ease;
      outline: none;
    }

    .floating-input__field:focus {
      border-bottom-color: var(--accent-color);
    }

    .floating-input__field:focus + .floating-input__label,
    .floating-input__field:not(:placeholder-shown) + .floating-input__label,
    .floating-input__field.has-value + .floating-input__label {
      top: -8px;
      font-size: 12px;
      color: var(--accent-color);
    }

    .floating-input__label {
      position: absolute;
      left: 0;
      top: 12px;
      color: var(--text-light);
      font-size: 16px;
      transition: all var(--transition-speed) ease;
      pointer-events: none;
    }

    .floating-input__hint {
      font-size: 13px;
      color: var(--text-light);
      margin-top: 6px;
      display: block;
    }

    /* ==================== STRIPE CARD ELEMENT ==================== */
    #card-element {
      padding: 12px 0;
      border-bottom: 2px solid var(--border-color);
      transition: border-color 0.3s ease;
    }

    #card-element.StripeElement--focus {
      border-bottom-color: var(--accent-color);
    }

    #card-element.StripeElement--invalid {
      border-bottom-color: #dc3545;
    }

    /* ==================== CONDITIONAL ADDRESS FIELD ==================== */
    #billing-address-group {
      display: none;
      opacity: 0;
      transition: opacity 0.3s ease;
    }

    #billing-address-group.visible {
      display: block;
      opacity: 1;
    }

    /* ==================== BUTTONS ==================== */
    .btn {
      padding: 14px 32px;
      border: none;
      border-radius: 8px;
      font-size: 16px;
      font-weight: 600;
      cursor: pointer;
      transition: all var(--transition-speed) ease;
      text-decoration: none;
      display: inline-block;
      text-align: center;
      width: 100%;
    }

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

    .btn-primary:hover:not(:disabled) {
      background: var(--primary-light);
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(42, 53, 72, 0.3);
    }

    .btn-primary:disabled {
      opacity: 0.6;
      cursor: not-allowed;
    }

    .btn-primary.loading {
      position: relative;
      color: transparent;
    }

    .btn-primary.loading:after {
      content: "";
      position: absolute;
      width: 20px;
      height: 20px;
      top: 50%;
      left: 50%;
      margin-left: -10px;
      margin-top: -10px;
      border: 2px solid #fff;
      border-radius: 50%;
      border-top-color: transparent;
      animation: spinner 0.6s linear infinite;
    }

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

    /* ==================== ERROR MESSAGES ==================== */
    #card-errors {
      color: #dc3545;
      font-size: 14px;
      margin-top: 12px;
      min-height: 20px;
    }

    /* ==================== SECURITY NOTE ==================== */
    .security-note {
      background: var(--bg-light);
      border-radius: 8px;
      padding: 16px;
      margin-top: 20px;
      font-size: 14px;
      color: var(--text-light);
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .security-note:before {
      content: "🔒";
      font-size: 20px;
    }

    /* ==================== SUCCESS MESSAGE ==================== */
    .success-message {
      background: white;
      border-radius: 12px;
      padding: 40px;
      box-shadow: 0 4px 20px rgba(0,0,0,0.08);
    }

    .success-message__icon {
      font-size: 64px;
      margin-bottom: 20px;
      text-align: center;
    }

    .success-message__title {
      font-size: 28px;
      font-weight: 700;
      color: var(--primary-color);
      margin-bottom: 16px;
      text-align: center;
    }

    .success-message__text {
      font-size: 16px;
      color: var(--text-dark);
      line-height: 1.8;
      margin-bottom: 12px;
    }

    .success-message__note {
      font-size: 14px;
      color: var(--text-light);
      margin-top: 24px;
      padding-top: 24px;
      border-top: 1px solid var(--border-color);
    }

    /* ==================== WARNING MESSAGE ==================== */
    .warning-message {
      background: #fff3cd;
      border: 2px solid var(--warning-color);
      border-radius: 12px;
      padding: 32px;
      box-shadow: 0 4px 20px rgba(0,0,0,0.1);
      text-align: center;
    }

    .warning-message__icon {
      font-size: 48px;
      margin-bottom: 16px;
    }

    .warning-message__title {
      font-size: 24px;
      font-weight: 700;
      color: #856404;
      margin-bottom: 12px;
    }

    .warning-message__text {
      font-size: 16px;
      color: #856404;
      line-height: 1.6;
      margin-bottom: 8px;
    }

    .warning-message__countdown {
      font-size: 14px;
      color: #856404;
      margin: 16px 0;
    }

    /* ==================== RESPONSIVE ==================== */
    @media (max-width: 768px) {
      .main-container {
        padding: 20px 15px;
      }

      .payment-section {
        padding: 24px;
      }

      .section-title {
        font-size: 22px;
      }

      .header__logo {
        font-size: 20px;
      }

      .header__text {
        font-size: 16px;
      }
    }

    @media (max-width: 480px) {
      .payment-section {
        padding: 20px;
      }

      .section-title {
        font-size: 20px;
      }
    }