style.css

* {
  margin: 0;
  padding: 0;
  overflow: x 0;
  overflow-x:hidden;
  font-family: "Poppins", sans-serif;
}

.grid {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  width: 440px;
  height: 440px;
  background-color: white;
  max-width: 100%;
}
.new-content {
  margin: 0;
  padding: 0;
  top:0;
  bottom:0;
  left:0;
  right:0;
  height:max-content;
  width: 100%;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  vertical-align: center;
  max-width: 100%;
}

html {
  background: black;
  background-size: 100% 100%;
}
body {
  align-items: center;
  max-width: 100%;
}
.grid div {
  display: flex;
  position: relative;
  width: 90px;
  height: 90px;
  background-color: white;
  color: black;
  border: solid;
  border-width: 10px;
  font-size: 250%;
  font-weight: bold;
  justify-content: center;
  align-items: center;
  vertical-align: middle;
  text-shadow: 2px 2px 3px rgb(63, 60, 60);
}
.stop-button {
  float: right;
  justify-content: right;
  margin-left: 80%;
}
.heading {
  position: relative;
  margin-top: 5%;
  margin-bottom: 1%;
  border: solid;
  background: linear-gradient(90deg, #14ffe9, #ffeb3b, #ff00e0, #6e1df0);
  border-width: 5px;
  border-color: rgb(48, 46, 46);
}
.head {
  max-width: 100%;
  text-align: center;
}
#score {
  position: fixed;
  display:contents;
  color: rgb(241, 238, 237);
  justify-content: center;
  margin-top: 20%;
}

#result {
  color: white;
}

@media only screen and (min-width: 300px) and (max-width: 490px) {
  *{
    margin: 0;
    padding: 0;
    overflow:hidden;
  }
  div.new-content {
    max-width: 100%;
  }
  .grid {
    width: 370px;
    height: 370px;
  }
  .grid div {
    width: 82.5px;
    height: 82.5px;
    border-width: 5px;
  }
  .html {
    justify-content: center;
    align-items: center;
    orientation: landscape;
  }
 
}