*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
    font-family: Arial, sans-serif;
    /* margin: 0;
    padding: 0; */
    background-color: #f2f2f2;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 60vh;
  }
  .header{
    margin-top: 100px;
    margin-bottom: 5px;
    font-size: 10px;
  }
  .header h1{
    font-size: 30px;
    color: blue;
    text-align: center;
  }
  #key{
    font-size: 10px;
    /* margin-top: 5px; */
    text-align: center;
  }
  h4{
    text-align: left;
    font-size: 12px;
   /* padding-left: 80px; */
    padding-bottom: 5px:
  }

  #container {
    /* display: flex; */
    /* height: 100vh;
    margin: 50px;
    margin-top: 100px; */

    display: inline-block;
    /* margin-top: 200px; */
    text-align: center;
    border: 3px #0051ff91 solid;
    width: 60% ;
    height: 80vh;
    padding: 10px 0px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  }
  button {
    padding: 10px 20px;
    font-size: 14px;
    cursor: pointer;
    background-color: #4caf50;
    color: #fff;
    border: none;
    border-radius: 10px;
    margin-top: 10px;
    margin-left: 20px;
    width: 35%;
  }
  
  button:hover {
    background-color: #45a049;
  }

  #problem-container {
    flex: 1;
    padding: 20px;
    box-sizing: border-box;
  }

  #plot-container {
    flex: 2;
    position: relative;
  }

  #equation {
    margin-bottom: 20px;
    /* margin-top: 10px; */
  }

  #user-input {
    margin-bottom: 10px;
    height: 30px;
  }

  #feedback {
    margin-top: 10px;
    font-weight: bold;
  }

  #plot {
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
  }

  .red-dot {
    position: absolute;
    width: 10px;
    height: 10px;
    background-color: red;
    border-radius: 50%;
    transform: translate(-50%, -50%);
  }

  .tick {
    position: absolute;
    width: 2px;
    height: 10px;
    background-color: black;
    transform-origin: bottom;
  }

  .tick-label {
    position: absolute;
    top: 20px;
    transform: translateX(-50%);
  }

  .horizontal-line {
    position: absolute;
    width: 100%;
    height: 2px;
    background-color: black;
    /* top: 40px; */
  }