/* General reset and font settings */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  background-color: #f7f7f7;
}

/* App container styling */
.app-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 30px;
  min-height: 100vh;
  max-width: 900px;
  margin: auto;
  background-color: #ffffff;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

/* Heading styling */
h1 {
  font-size: 2.5rem;
  margin-bottom: 20px;
  color: #333;
  text-align: center;
}

/* Navigation links styling */
nav {
  position: absolute;
  top: 20px;
  left: 20px;
  right: 20px;
  display: flex;
  justify-content: space-between;
  font-size: 1rem;
  color: #333;
}

nav a {
  text-decoration: none;
  color: #3498db;
  margin-right: 20px;
  transition: color 0.3s;
}

nav a:hover {
  color: #2980b9;
}

/* Textarea styling */
textarea {
  width: 100%;
  max-width: 600px;
  height: 150px;
  padding: 10px;
  font-size: 16px;
  border-radius: 8px;
  margin-bottom: 20px;
  border: 1px solid #ccc;
  resize: none;
  min-width: 300px;
  max-width: 100%;
}

/* Button styling */
button {
  padding: 10px 20px;
  font-size: 18px;
  background-color: #3498db;
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background-color 0.3s;
  width: 100%;
  max-width: 200px;
}

button:hover {
  background-color: #2980b9;
}

/* Payment form styling */
#payment-form {
  margin-top: 30px;
  padding: 20px;
  background-color: #f9f9f9;
  border-radius: 8px;
  width: 100%;
  max-width: 600px;
}

#payment-form h2 {
  font-size: 1.5rem;
  margin-bottom: 15px;
  color: #333;
}

#card-element {
  margin-bottom: 20px;
}

#card-errors {
  color: red;
  font-size: 0.9rem;
  margin-top: 10px;
}

/* Form error styling */
.message {
  color: red;
  font-size: 1rem;
  margin-top: 15px;
  text-align: center;
}