*{
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  body {
  font-family: Arial, Helvetica, sans-serif;
  font-size: ;
  }

  .bg {
    width: 100%;
    height: 100vh;
    background-image: url(./background.png);
    background-size: cover;
    background-position: center;
    position: relative;
    overflow: hidden;
  }

  .bubbles img {
    width: 50px;
    animation: bubble 7s linear infinite;
  }

  .bubbles {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-around;
    position: absolute;
    bottom: -70px;
  }

  @keyframes bubble {
    0%{
      transform: translateY(0);
      opacity: 0;
    }
    25%{
      opacity: 1;
    }
    50%{
      opacity: 1;
    }
    75%{
      opacity: 1;
    }
    100%{
      transform: translateY(-105vh);
      opacity: 0;
    }
  }

  .bubbles img:nth-child(1) {
    animation-delay: 0.7s;
    width: 25px;
  }
  .bubbles img:nth-child(2) {
    animation-delay: 1.5s;
  }
  .bubbles img:nth-child(3) {
    animation-delay: 2s;
    width: 35px;
  }
  .bubbles img:nth-child(4) {
    animation-delay: 1s;
  }
  .bubbles img:nth-child(5) {
    animation-delay: 2.5s;
    width: 20px;
  }
  .bubbles img:nth-child(6) {
    animation-delay: 3.5s;
    width: 40px;
  }
  .bubbles img:nth-child(7) {
    animation-delay: 1s;
    width: 25px;
  }
  .bubbles img:nth-child(8) {
    animation-delay: 2.7s;
  }

  /**start**/
  nav {
    background: rgba(0, 0, 0, 0.6);
    color: #fff;
    padding: 0 0 7.5px 10px;
    width: 100%;
    float: top;
    font-size: xx-large;
    text-decoration: none;
    text-transform: uppercase;
  }
  nav .nav {
    text-align: center;
    float: right;
  }
  nav ul li a {
    display: block;
    box-shadow: inset 0 0 0 0 #fff;
    color: #fff;
    font-size: x-large;
    text-decoration: none;
    text-transform: none;
    padding: 10px 20px;
    transition: color .5s ease-in-out, box-shadow .3s ease-in-out;
  }
  nav ul li a:hover{
    text-decoration: none;
    cursor: pointer;
    color: #000;
    box-shadow: inset 200px 0 0 0 rgb(255, 255, 255, 0.9);
  }
  /*End navbar*/

  .row {
    width: 100%;
    padding: 5%;
  }

  .column {
    float: left;
    width: 45%;
    padding: 5%;
    color: #fff;
    background: rgba(0, 0, 0, 0.5);
    border-radius: 15px;
  }

  #pwdgen {
    height: 35%;
  }
  
  #btn {
    margin: 3px;
    width: 120px;
    border-radius: 5px;
  }

  input {
    width:100%;
    margin: 3px;
    border-radius: 5px;
  }

  footer {
    width: 100%;
    background: #000;
    color: #fff;
    padding: 5px;
    font-size: small;
    letter-spacing: 1px;
    display: flex;
    justify-content: center;
    text-align: center;
    margin-top: 0;
  }

  footer a {
    text-decoration: none;
  }

  /* Responsive layout - makes the two columns stack on top of each other instead of next to each other */
  @media screen and (max-width: 600px) {
    *{
      box-sizing: border-box;
      margin:0;
      padding: 0;
    }

  /**start**/
  nav {
    height: 7vh;
    padding: 0 0 0 12px;
    font-size: x-large;
  }
  nav ul li a {
    margin-top: -100%;
  }
  /*End navbar*/

    .column {
      margin-left: 15%;
      width: 80%;
      margin-bottom: 5%;
    }
  }

  #btn {
    width: 70px;
  }