* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    text-decoration: none;
    border: none;
    outline: none;
    scroll-behavior: smooth;
    font-family: "poppins", sans-serif;
}
:root{
    background-color: black;
    --text-color: white;
    --main-color: rgb(202, 69, 69);
}
html{
    font-size: 62.5%;
    overflow-x: hidden;
}
body{
    background: var(--bg-color);
    color: var(--text-color);
}
.header{
    position: fixed;
    top: -1%;
    left: 0;
    right: 5%;
    width: 100%;
    padding: 3rem 9%;
    background: rgba(0, 0, 0, 0.589);
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
}
.logo{
    font-size: 3rem;
    color: var(--text-color);
    font-weight: 800;
    cursor: pointer;
    transition: 0.3s ease-in-out;
}
.logo:hover{
    transform: scale(1.1);
}
.navbar a{
    font-size: 1.8rem;
    color: white;
    margin-left: 4rem;
    font-weight: 500;
    transition: 0.3s ease-in-out;
    border-bottom: 3px solid transparent;
}
.navbar a.active::before {
    content: '';
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 100%;
    height: .2rem;
    background: var(--white-color);
}
.navbar a:hover,
.navbar a.active{
    color: var(--main-color);
    border-bottom: 3px solid var(--main-color);
}
* {
    box-sizing: border-box;
    margin: 0;
  }
  
  .calculator {
    background-color: #f2f2f2;
    padding: 20px;
    max-width: 400px;
    margin: 0 auto;
    border: solid 1px #ccc;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    border-radius: 5px;
    margin-top: 180px;
  }
  
  #result{
      width: 100%;
      padding: 10px;
      font-size: 24px;
      border: none;
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3) inset;
      border-radius: 5px;
  }
  
  .buttons{
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      grid-gap: 10px;
      margin-top: 20px;
  }
  
  button{
      padding: 10px;
      font-size: 24px;
      border: none;
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
      border-radius: 5px;
      cursor: pointer;
      transition: background-color 0.3s ease;
  
  }
  
  button:hover{
      background-color: #ddd;
  }
  
  .clear{
      background-color: #ff4136;
      color: #fff;
  }
  
  .number, .decimal{
      background-color: #fff;
      color: #333;
  
  }
  
  .operator{
      background-color: #0074d9;
      color: #fff;
  }
  
  .equals{
      background-color: #01ff70;
      grid-row: span 3;
      color: #fff;
  }