:root {
      --field-border: 1px solid #e0e0e0;
      --field-border-radius: 0.75em;
      --secondary-text: #6c757d;
      --sidebar-color: #f8f9fa;
      --accent-color: #04425D;
      --success-color: #00c853;
      --light-accent: #E8F4F8;
    }

    * { box-sizing: border-box; }

    body {
      font-size: 14px;
      font-family: "Segoe UI", Roboto, sans-serif;
      background: #f5f5f5;
      min-height: 100vh;
      padding: 1rem 0;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .main-container {
      width: 100%;
      max-width: 1200px;
      padding: 0 15px;
    }

    .payment-wrapper {
      background: white;
      border-radius: 20px;
      box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
      overflow: hidden;
    }

    /* Sol kısım */
    .info-section {
      background: #04425D;
      color: white;
      padding: 3rem;
      min-height: 100%;
    }

    .info-header h2 {
      font-size: 1.8rem;
      font-weight: 700;
      margin-bottom: 0.5rem;
    }

    .info-header p {
      font-size: 1rem;
      opacity: 0.9;
    }

    .info-item {
      display: flex;
      align-items: flex-start;
      margin-bottom: 1.8rem;
    }

    .info-icon {
      width: 45px;
      height: 45px;
      background: rgba(255, 255, 255, 0.2);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-right: 1rem;
      flex-shrink: 0;
    }

    .info-content h3 {
      font-size: 1.1rem;
      margin-bottom: 0.25rem;
    }

    .info-content p {
      font-size: 0.9rem;
      opacity: 0.9;
    }

    .security-badge {
      margin-top: 2.5rem;
      padding: 1rem;
      background: rgba(255, 255, 255, 0.15);
      border-radius: 10px;
    }

    .security-badge h4 {
      font-size: 1rem;
      display: flex;
      align-items: center;
      gap: 0.5rem;
      margin-bottom: 0.3rem;
    }




    /* Sağ taraf (form) */
    .form-section {
      padding: 3rem;
    }

    .header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 2rem;
      padding-bottom: 1rem;
      border-bottom: 2px solid #f0f0f0;
    }

    .logo-section {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }

    .logo-icon {
      width: 45px;
      height: 45px;
      background: #04425D;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 22px;
    }

    .logo-text h1 {
      font-size: 1.4rem;
      margin: 0;
      color: #2c3e50;
    }

    .logo-text span {
      font-size: 0.8rem;
      color: var(--secondary-text);
    }

    .form-group-custom {
      margin-bottom: 5px;
    }

    .form-label-custom {
      font-weight: 600;
      font-size: 0.9rem;
      color: #2c3e50;
      margin-bottom: 0.4rem;
      display: block;
    }

    .form-sublabel {
      font-size: 0.8rem;
      color: var(--secondary-text);
      margin-bottom: 0.5rem;
      display: block;
    }

    .input-wrapper {
      position: relative;
      display: flex;
      align-items: center;
      border: 2px solid #e0e0e0;
      border-radius: var(--field-border-radius);
      padding: 0.65rem 1rem;
      transition: all 0.3s ease;
      background: #fafafa;
    }


    
    .select-input {
      position: relative;
      display: flex;
      align-items: center;
      border: 2px solid #e0e0e0;
      border-radius: var(--field-border-radius);
      padding: 0.65rem 1rem;
      transition: all 0.3s ease;
      background: #fafafa;
      width: 100%;
    }

    .input-wrapper:focus-within {
      border-color: var(--accent-color);
      background: white;
      box-shadow: 0 0 0 3px rgba(4, 66, 93, 0.1);
    }

    .input-wrapper input {
      border: none;
      background: transparent;
      flex: 1;
      padding: 0.25rem 0.5rem;
      font-size: 0.95rem;
      color: #2c3e50;
      outline: none;
    }

    .input-icon {
      color: var(--secondary-text);
      font-size: 18px;
      margin-left: 0.5rem;
    }

    .card-number-input {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }

    .card-brand-icon {
      width: 35px;
      height: 35px;
      flex-shrink: 0;
    }

    .expiry-cvv-row {
      display: grid;
      grid-template-columns: 1fr -1fr;
      gap: 1rem;
    }

    .expiry-inputs {
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }

    .expiry-separator {
      font-size: 1.1rem;
      font-weight: 600;
      color: var(--secondary-text);
    }

    .btn-pay {
      width: 100%;
      padding: 1rem;
      background: #04425D;
      color: white;
      border: none;
      border-radius: var(--field-border-radius);
      font-size: 1rem;
      font-weight: 600;
      cursor: pointer;
      transition: all 0.3s ease;
      margin-top: 1.5rem;
    }

    .btn-pay:hover {
      background: #055a7d;
      transform: translateY(-2px);
      box-shadow: 0 10px 20px rgba(4, 66, 93, 0.3);
    }

    .order-summary {
      background: var(--sidebar-color);
      border-radius: 12px;
      padding: 1.2rem;
      margin-top: 1.5rem;
    }

    .order-summary h3 {
      font-size: 1rem;
      margin-bottom: 0.8rem;
      color: #2c3e50;
    }

    .order-item {
      display: flex;
      justify-content: space-between;
      padding: 0.6rem 0;
      border-bottom: 1px solid #e0e0e0;
      font-size: 0.9rem;
    }

    .order-item:last-child {
      border-bottom: none;
      padding-top: 0.8rem;
      margin-top: 0.5rem;
      border-top: 2px solid #2c3e50;
    }

    .order-total strong {
      font-size: 1.2rem;
      color: var(--accent-color);
    }

    .secure-badge {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      margin-top: 1rem;
      color: var(--success-color);
      font-size: 0.85rem;
    }

    /* Mobil uyumluluk */
    @media (max-width: 992px) {
      .info-section { padding: 2rem; text-align: center; }
      .info-item { flex-direction: column; align-items: center; }
      .info-icon { margin-bottom: 0.75rem; }
    }

    @media (max-width: 768px) {
      .payment-wrapper {
        border-radius: 0;
        box-shadow: none;
      }
      .row.g-0 {
        flex-direction: column;
      }
      .info-section, .form-section {
        padding: 5px;
      }
      .expiry-cvv-row {
        grid-template-columns: 1fr;
      }
      .btn-pay {
        font-size: 1rem;
      }
    }

    @media (max-width: 480px) {
      .info-header h2 { font-size: 1.5rem; }
      .logo-text h1 { font-size: 1.2rem; }
      .input-wrapper { padding: 0.5rem 0.75rem; }
      .input-wrapper input { font-size: 0.85rem; }
      .btn-pay { padding: 0.9rem; }
    }


    /* Kart Önizleme Genel Alanı */
.card-preview {
  position: relative;
  width: 100%;
  max-width: 420px;
  height: 250px;
  margin: 0 auto;
  perspective: 1000px;
  cursor: pointer;
  transition: transform 0.4s ease;
}

/* Kart iç yüzey (ön/arka) */
.card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.8s ease;
  transform-style: preserve-3d;
}

/* Kart döndürülme efekti */
.card-preview.flipped .card-inner {
  transform: rotateY(180deg);
}

/* Ortak kart stilleri */
.card-front,
.card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  border-radius: 20px;
  backface-visibility: hidden;
  background: linear-gradient(135deg, #2b2d42, #212338);
  color: #fff;
  padding: 1.5rem;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  overflow: hidden;
}

/* Kart ön yüz */
.card-front {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

/* Çip görseli */
.card-chip {
  width: 50px;
  height: 35px;
  border-radius: 6px;
  background: linear-gradient(135deg, #f1c40f, #f39c12);
  box-shadow: 0 0 3px rgba(0,0,0,0.3);
}

/* Kart numarası */
.card-number-display {
  font-family: "Courier New", monospace;
  font-size: 1.3rem;
  letter-spacing: 2px;
  color: #fff;
  text-shadow: 0 0 4px rgba(255,255,255,0.3);
}

/* Sahip / Tarih bilgileri */
.card-holder .label {
  font-size: 0.8rem;
  opacity: 0.8;
}

.card-holder div {
  font-size: 1rem;
}

/* Kart logosu */
.card-logo {
  font-size: 1.5rem;
  opacity: 0.8;
}

/* Arka yüz */
.card-back {
  background: linear-gradient(135deg, #1e1f2a, #2e3043);
  transform: rotateY(180deg);
}

/* Siyah şerit */
.card-back .black-strip {
  width: 100%;
  height: 50px;
  background: #000;
  margin-top: 10px;
  border-radius: 4px;
}

/* CVV kutusu */
.cvv-box {
  background: #fff;
  color: #000;
  width: 90%;
  margin: 1rem auto;
  padding: 0.5rem 0.8rem;
  border-radius: 6px;
  text-align: right;
}

/* Mobil uyumluluk */
@media (max-width: 768px) {
  .card-preview {
    max-width: 320px;
    height: 190px;
  }

  .card-chip {
    width: 40px;
    height: 28px;
  }

  .card-number-display {
    font-size: 1rem;
    letter-spacing: 1px;
  }

  .card-holder div {
    font-size: 0.9rem;
  }

  .card-logo {
    font-size: 1.2rem;
  }

  .cvv-box {
    width: 95%;
    padding: 0.4rem 0.6rem;
  }
}