* {
  box-sizing: border-box;
  font-family: system-ui, sans-serif;
}

body {
  background: linear-gradient(135deg, #2b5876, #4e4376);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.converter {
  background: #ffffff;
  padding: 25px;
  border-radius: 12px;
  width: 320px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

h2 {
  text-align: center;
  margin-bottom: 20px;
}

.row {
  display: flex;
  gap: 10px;
}

input, select {
  padding: 10px;
  font-size: 16px;
  border-radius: 8px;
  border: 1px solid #ccc;
  width: 100%;
}

#swap {
  width: 100%;
  margin: 12px 0;
  padding: 8px;
  font-size: 18px;
  border-radius: 8px;
  border: none;
  background: #4e4376;
  color: white;
  cursor: pointer;
}

#swap:hover {
  opacity: 0.9;
}