body {
  font-family: 'Segoe UI', Tahoma, sans-serif;
  background: #eaf7ed; /* hellgrüner Hintergrund */
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  margin: 0;
}

form {
  background: #ffffff;
  padding: 2.5rem;
  border-radius: 12px;
  box-shadow: 0 4px 25px rgba(0, 80, 0, 0.1);
  width: 360px;
  text-align: center;
  border: 2px solid #4caf50;
}

form img {
  max-width: 350px;
  margin-bottom: 1.5rem;
}

h1 {
  color: #2e7d32;
  margin-bottom: 1.2rem;
  font-size: 1.8rem;
}

label {
  display: block;
  text-align: left;
  color: #2e7d32;
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-size: 1rem;
}

input {
  width: 100%;
  padding: 0.65rem;
  margin-bottom: 1rem;
  font-size: 1rem;
  border: 1.5px solid #4caf50;
  border-radius: 6px;
  box-sizing: border-box;
}

input:focus {
  outline: none;
  border-color: #388e3c;
  box-shadow: 0 0 6px rgba(56, 142, 60, 0.3);
}

button {
  background-color: #4caf50;
  border: none;
  color: white;
  font-weight: bold;
  padding: 0.7rem 1.2rem;
  font-size: 1.1rem;
  border-radius: 6px;
  width: 100%;
  transition: background-color 0.3s ease;
}

button:hover {
  background-color: #388e3c;
}

#error-message {
  color: #b71c1c;
  margin-top: 0.5rem;
  font-weight: 600;
  display: none;
}