body { font-family: sans-serif; background: #f0f2f5; display: flex; justify-content: center; align-items: center; height: 100vh; margin: 0; }
.converter-box { background: white; padding: 30px; border-radius: 12px; box-shadow: 0 10px 30px rgba(0,0,0,0.1); width: 350px; }
h2 { margin-top: 10px; color: #333; }
select, input { width: 100%; padding: 12px; margin: 8px 0; border: 1px solid #ddd; border-radius: 8px; font-size: 16px; }
.row { display: flex; gap: 10px; }
.equals { text-align: center; font-weight: bold; font-size: 20px; color: #007bff; margin: 5px; }
input[readonly] { background: #f9f9f9; color: #007bff; font-weight: bold; border-color: #007bff; }