* {
  box-sizing: border-box;
  font-family: "Segoe UI", sans-serif;
}

body {
  min-height: 100vh;
  background: #042453;
  display: flex;
  justify-content: center;
  align-items: center;
}

.crypto-container {
  background: #ffffff;
  width: 320px;
  padding: 25px;
  border-radius: 14px;
  text-align: center;
  box-shadow: 0 20px 40px rgba(0,0,0,0.25);
}

h2 {
  margin-bottom: 15px;
}

select {
  width: 100%;
  padding: 10px;
  border-radius: 6px;
  border: 1px solid #ccc;
  margin-bottom: 10px;
}

button {
  width: 100%;
  padding: 10px;
  border: none;
  border-radius: 6px;
  background: #4f46e5;
  color: white;
  cursor: pointer;
}

.result {
  margin-top: 15px;
  font-size: 14px;
  font-weight: 600;
}

.error {
  color: red;
}