style.css

body {
  direction: rtl;
  background-color: #212121;
}
/* Mobile style */
.container {
  display: grid;
  grid-template-areas:
    "hd"
    "con1"
    "con2"
    "result"
    "btn";
  color: aliceblue;
}

/* computer style */
@media (min-width: 768px) {
  .container {
    grid-template-areas:
      "hd"
      "con1 con2"
      "result"
      "btn";
    grid-template-rows: minmax(200px, 1fr);
  }
}

.container > * {
  padding: 10px;
  margin: 0;
  background-color: navy;
}

.title {
  grid-area: hd;
  background-color: #333;
}
.table-options {
  grid-area: con1;
}
.input {
  grid-area: con2;
}
.results {
  background-color: #333;
  grid-area: result;
}
.button {
  grid-area: btn;
}

.red {
  background-color: red;
  padding: 10px;
}
.green {
  background-color: green;
  padding: 10px;
}
.alert {
  background-color: gold;
  color: #333;
  padding: 10px;
}
input,
select,
label,
button {
  padding: 10px;
  font-size: 24px;
}
input,
select,
label,
button,
.green,
.red,
.alert {
  transition: all 0.5s linear;
  border-radius: 5px;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  -ms-border-radius: 5px;
  -o-border-radius: 5px;
  -webkit-transition: all 0.5s linear;
  -moz-transition: all 0.5s linear;
  -ms-transition: all 0.5s linear;
  -o-transition: all 0.5s linear;
}