body {
  font-family: 'Poppins', sans-serif;
  background-color: #f7f8fa;
  color: #596172;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 0;
  padding: 0;
  min-height: 100vh;
}

.container {
  background: #ffffff;
  border: 2px solid #E4E4E7;
  border-radius: 10px;
  padding: 30px;
  width: 90%;
  max-width: 500px;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.05);
  margin-top: 40px;
}

h1 {
  color: #48d6de;
  text-align: center;
  margin-bottom: 20px;
}

.form label {
  display: block;
  margin-top: 15px;
  font-weight: 500;
}

.form input {
  width: 100%;
  padding: 10px;
  border: 1px solid #E4E4E7;
  border-radius: 5px;
  margin-top: 5px;
  font-size: 16px;
  transition: 0.2s ease;
}

.form input:focus {
  border-color: #48d6de;
  outline: none;
  box-shadow: 0 0 5px rgba(72, 214, 222, 0.3);
}

button {
  background-color: #48d6de;
  color: #fff;
  border: none;
  border-radius: 5px;
  padding: 12px 18px;
  font-size: 16px;
  cursor: pointer;
  margin-top: 20px;
  width: 100%;
  transition: 0.3s;
}

button:hover {
  background-color: #3ac1c8;
}

.message-box {
  margin-top: 25px;
  background-color: #f0fcfd;
  border: 1px solid #E4E4E7;
  border-radius: 8px;
  padding: 20px;
  display: none;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.message-box.show {
  display: block;
  opacity: 1;
  transform: translateY(0);
}

#birthdayMessage {
  font-size: 18px;
  color: #596172;
  white-space: pre-line;
}

.hidden {
  display: none;
}

footer {
  margin-top: auto;
  text-align: center;
  padding: 15px;
  background-color: #fafafa;
  border-top: 1px solid #E4E4E7;
  width: 100%;
  color: #596172;
  font-size: 14px;
}

footer a {
  color: #48d6de;
  text-decoration: none;
  font-weight: 500;
}

@media (max-width: 600px) {
  .container {
    padding: 20px;
    width: 95%;
  }

  h1 {
    font-size: 22px;
  }

  #birthdayMessage {
    font-size: 16px;
  }

  button {
    font-size: 15px;
    padding: 10px;
  }
}