body {
  font: 300 16px Roboto, sans-serif;
  background: #f5f5f7;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
  margin: 0;
  padding: 20px;
}

.payment-form {
  background: white;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
  padding: 32px;
  width: 100%;
  max-width: 400px;
}

.payment-form h1 {
  color: #1a1a1a;
  margin: 0 0 24px 0;
  font-size: 24px;
  font-weight: 600;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  color: #666;
  font-size: 14px;
  margin-bottom: 6px;
}

.form-group input {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid #ddd;
  border-radius: 8px;
  font-size: 16px;
  transition: border-color 0.2s;
}

.form-group input:focus {
  border-color: #7b61ff;;
  outline: none;
}

.row {
  display: flex;
  gap: 16px;
}

.row .form-group {
  flex: 1;
}

button {
  width: 100%;
  padding: 14px;
  background: #7b61ff;
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 500;
  cursor: pointer;
  margin-top: 8px;
  transition: all 0.2s;
}

button:hover {
  background: #0056CC;
}

header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 24px;
  display: flex;
  justify-content: space-between;
}

form {
  padding: 32px;
  background: #ffffff;
  border-radius: 20px;
  box-shadow: 0 0 20px #4a558c26;
  min-width: 320px;
}

p {
  padding: 0;
  margin: 6px 0 18px;
  font: 300 16px Roboto, sans-serif;
}

h2 {
  width: 100%;
  text-align: center;
}

.field {
  border-bottom: 1px solid #E1E4EA;
  padding: 4px 0;
}

input {
  padding: 8px;
  margin-bottom: 20px;
  width: calc(100% - 16px);
  border: 1px solid #E1E4EA;
  border-radius: 8px;
  transition: all .3s linear;
}

input.required {
  border: 2px solid #ef400f;  
}