body {
  font-family: "Segoe UI", Arial, sans-serif;
  background: linear-gradient(120deg, #f8fafc 0%, #e0e7ef 100%);
  padding: 40px;
  max-width: 420px;
  margin: 40px auto;
  border-radius: 18px;
  box-shadow: 0 4px 24px 0 rgba(60, 80, 120, 0.1);
}
h1 {
  text-align: center;
  color: #2a4365;
  margin-bottom: 28px;
  font-size: 2rem;
  letter-spacing: 1px;
}
label {
  display: block;
  margin-top: 18px;
  color: #374151;
  font-weight: 500;
  letter-spacing: 0.5px;
}
input[type="number"],
select {
  width: 100%;
  padding: 10px 12px;
  margin-top: 7px;
  border: 1px solid #cbd5e1;
  border-radius: 7px;
  font-size: 1rem;
  background: #f9fafb;
  transition: border 0.2s;
  box-sizing: border-box;
}
input[type="number"]:focus,
select:focus {
  border: 1.5px solid #2563eb;
  outline: none;
  background: #fff;
}
button {
  margin-top: 28px;
  padding: 12px 0;
  width: 100%;
  background: linear-gradient(90deg, #2563eb 0%, #60a5fa 100%);
  color: #fff;
  font-size: 1.1rem;
  font-weight: 600;
  border: none;
  border-radius: 7px;
  cursor: pointer;
  box-shadow: 0 2px 8px 0 rgba(37, 99, 235, 0.08);
  transition: background 0.2s, box-shadow 0.2s;
}
button:hover {
  background: linear-gradient(90deg, #1d4ed8 0%, #3b82f6 100%);
  box-shadow: 0 4px 16px 0 rgba(37, 99, 235, 0.13);
}
button:active {
  transform: scale(0.97);
  transition: transform 0.1s;
}
.result {
  margin-top: 32px;
  padding: 28px 22px;
  background: linear-gradient(120deg, #e0e7ef 0%, #f8fafc 100%);
  border-radius: 16px;
  color: #1e293b;
  font-size: 1.18rem;
  font-weight: 500;
  box-shadow: 0 4px 24px 0 rgba(60, 80, 120, 0.1);
  min-height: 70px;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s cubic-bezier(0.4, 0, 0.2, 1),
    transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  justify-content: center;
  letter-spacing: 0.5px;
  border: 1.5px solid #cbd5e1;
}
.result.visible {
  opacity: 1;
  transform: translateY(0);
}
.paymentNote {
  font-size: 0.9rem;
  color: #000000;
  margin-top: 10px;
  text-align: center;
  font-weight: bold;
}
form {
  animation: fadeInForm 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}
@keyframes fadeInForm {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}
/* Add a custom arrow for the dropdown */
select {
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 18px 18px;
}
@media (max-width: 600px) {
  body {
    padding: 10px;
    max-width: 98vw;
    margin: 10px auto;
  }
  .result {
    padding: 14px 7px;
    font-size: 1rem;
  }
}