index.css

    .todobutton{
        background-color: aquamarine;
        width: 50px;
        height: 25px;
        border: none;

    }
input{
border: none;
border-bottom: 5px solid rgb(20, 207, 67);
width: 230px;
height: 30px;
}
    * {
      box-sizing: border-box;
    }
    
    body {
      background: linear-gradient(to right, 	rgb(140, 255, 102), rgb(137, 255, 172), 	rgb(140, 255, 102));

  }

  p{
    font-family: 'Roboto', sans-serif;
  }
    

    .column {
      float: left;
      width: 25%;
      padding: 0 10px;
    }
    

    .row {margin: 0 -5px;}
    
 
    .row:after {
      content: "";
      display: table;
      clear: both;
    }
    

    @media screen and (max-width: 600px) {
      .column {
        width: 100%;
        display: block;
        margin-bottom: 20px;
      }
    }
      .card {
      box-shadow: 0 4px 8px 3px rgba(0, 0, 0, 0.2);
      padding: 16px;
      text-align: center;
      background-color: #73e4ac;
    }

.linkbutton{
  height: 40px;
  width: 80px;
  border: none;
  background-color: red
}
.clock{
  font-size: 50px;
}

.sidenav {
  height: 100%;
  width: 0;
  position: fixed;
  z-index: 1;
  top: 0;
  left: 0;
  background-color: #111;
  overflow-x: hidden;
  transition: 0.5s;
  padding-top: 60px;
}

.sidenav a {
  padding: 8px 8px 8px 32px;
  text-decoration: none;
  font-size: 25px;
  color: #818181;
  display: block;
  transition: 0.3s;
}

.sidenav a:hover {
  color: #f1f1f1;
}

.sidenav .closebtn {
  position: absolute;
  top: 0;
  right: 25px;
  font-size: 36px;
  margin-left: 50px;
}

#main {
  transition: margin-left .5s;
  padding: 16px;
}

@media screen and (max-height: 450px) {
  .sidenav {padding-top: 15px;}
  .sidenav a {font-size: 18px;}
}

textarea {
  width: 100%;
  height: 200px;
  padding: 12px 20px;
  box-sizing: border-box;
  border: 2px solid #ccc;
  border-radius: 4px;
  background-color: #f8f8f8;
  font-size: 16px;
  resize: none;
}