body { font-family: Arial, sans-serif; background-color: #121212; color: #338ef7; text-align: center; font-size: 1.5rem; margin: 10% auto; width: 100%; } form { max-width: 300px; margin: 0 auto; } label, input { margin: 10px 0; color: #338ef7; font-size: 2rem; } input { width: 100%; padding: 10px; border: 1px solid #338ef7; border-radius: 5px; background-color: #333; box-sizing: border-box; text-align: center; } button { background-color: #338ef7; color: #efefef; border: none; margin-top: 15px; padding: 10px 20px; border-radius: 5px; cursor: pointer; font-size: 1rem; font-weight: bold; } input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; } input[type='number'] { -moz-appearance: textfield; }