style_sheet.css

body {
  background-color:  #202020;
  font-family: Arial;
  font-size: 15px;
}

.circle_base {
  position: absolute;
  height: 250px;
  width: 250px;
  background-color: gray;
  border-radius: 50%;
  top: 13%;
  left: 17%;
  z-index:-1;
  }


.myChart {
  height: 80%;
  width: 70%;
  background-color: gray;
  position: fixed;
  }

.head1 {
  color: black;
  text-align: center;
  padding: 20px;
  font-size: 40px;
  }

.text1 {
  color: white;
  text-align: center;
  font-size: 20px;
  font-family: Arial;
  padding: 10px;
  }

.a1 {
  color: white;
  padding: 10px;
  font-size: 15px;
  font-family: Arial;
  text-decoration: none;
}

.column {
  float: left;
  width: 50%;
  padding: 0px;
  padding-top: 25px;
  }

.slider {
  -webkit-appearance: none;
  width: 50%;
  height: 25px;
  background: gray;
  outline-style: solid;
  outline-color: white;
  opacity: 100;
}

.btn {
  background: white;
  color: #202020;
  border: none;
  font-size: 20px;
}

input {
  font-size: 20px;
  color: #202020;
}