style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
  }
  
  body {
    background: whitesmoke;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
  }
  
  .calc {
    align-items: center;
    background-color: #e3e0e0;
    display: flex;
    flex-direction: column;
    padding: 0.3rem;
    width: auto;
  }
  
  .calc-botoes {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    grid-gap: 2px;
  }
  
  button {
    width: 5rem;
    height: 3.5rem;
    border: none;
  }
  
  button:hover {
    background-color: #ccc;
  }
  
  .botoes-numericos {
    font-size: large;
    font-weight: bold;
  }
  
  .bgWhite {
    background-color: white;
  }
  
  .btnIgual {
    background-color: #95bff5; 
  }
  
  .btnIgual:hover {
    background-color: #75a9ee; 
  }
  
  .BtnsSinais {
    font-size: 20px;
  }
  
  .scroll {
    width: 20rem;
    overflow-x: auto;
    white-space: nowrap;
  }
  
  .display {
    font-weight: bold;
    width: 100%;
    text-align: end;
    font-size: 35px;
    padding: 15px 5px;
  }
  
  @media(max-width: 600px) {
    button {
      width: 4rem;
    }
  
    .scroll {
      width: 16rem;
    }
  }
  
  @media(max-width: 300px) {
    button {
      width: 3rem;
    }
  
    .scroll {
      width: 12rem;
    }
  }