HTMLify

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "sans";
  color: black;
  background-color: #19172e;
}

@font-face {
  src: url("font/sans.ttf");
  font-family: "sans";
}

.heading {
  color: white;
  padding-top: 10px;
  justify-content: center;
  text-align: center;
  font-size: 2rem;
}

.btn {
  background: #333;
  color: white;
  padding: 15px 60px;
  font-size: 1.5rem;
  margin: 20px auto;
  display: block;
  cursor: pointer;
  border-radius: 5px;
  border: none;
}

.btn:hover {
  background-color: #1e8e3e;
  color: white;
}

.item {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
}

.copy {
  color: white;
  padding: 15px 20px;
  font-size: 1.5rem;
  margin: 20px auto;
  background: #333;
  cursor: not-allowed ;
  border-radius: 5px;
  border: none;
  user-select: none;
}


.container {
  display: flex;
  flex-wrap: wrap;
}

.box {
  width: 33.3%;
  height: 150px;
  display: flex;
  justify-content: center;
  align-items: center;
  background: #19172e;
  border: 2px solid #19172e;
  border-radius: 8px;
  font-size: 1.5rem;
}

footer {
  text-align: center;
  color: white;
  font-size: 1rem;
  bottom: 0;
  margin-bottom: 0;
  padding: 5px;
  line-height: 3vh;
}

footer a:visited {
  color: inherit;
}


.body {
  display: flex;
  flex-direction: column;
}

@media (max-width: 500px) {
  .box {
    font-size: 0.8rem;
  }
}

@media (max-width: 450px) {
  .item {
    flex-direction: column;
  }
  .copy {
    margin-left: 0px;
    width: 100%;
  }
}

@media (max-width: 450px) {
  .copy {
    width: 100%;
  }
}


@media (max-width: 300px) {
  .copy {
    padding: 5px;
    width: fit-content;
    text-align: center;
  }
  .btn {
    padding: 5px;
  }
}