* {
  box-sizing: border-box;
}
body {
  margin: 0;
  background: #ffffff;
  color: #172e52;
  font:
    16px/1.5 Arial,
    Helvetica,
    sans-serif;
}
main {
  max-width: 900px;
  margin: auto;
  padding: 22px 30px;
}
header {
  background: #174c9b;
  color: white;
  padding: 14px 18px;
  font-size: 12px;
  letter-spacing: 2px;
  text-transform: uppercase;
}
h1 {
  font:
    900 38px/1.15 "Arial Black",
    Arial,
    sans-serif;
  letter-spacing: -1px;
  max-width: 720px;
  margin: 22px 0 14px;
}
main > p {
  max-width: 740px;
}
form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px 22px;
  border-top: 3px solid #174c9b;
  padding-top: 18px;
}
label {
  font-size: 13px;
  font-weight: bold;
}
label[for="values"],
textarea {
  grid-column: 1 / -1;
}
label[for="operation"] {
  grid-column: 1;
}
textarea,
select {
  width: 100%;
  background: #f5f8fd;
  color: #172e52;
  border: 1px solid #8ca3c5;
  padding: 12px;
  font:
    15px/1.4 "Courier New",
    monospace;
  border-radius: 0;
}
textarea {
  height: 80px;
  resize: vertical;
}
select {
  grid-column: 1;
}
button {
  grid-column: 2;
  align-self: end;
  justify-self: start;
  font:
    bold 14px Arial,
    sans-serif;
  border: 0;
  border-radius: 0;
  padding: 14px 22px;
  background: #174c9b;
  color: white;
  cursor: pointer;
}
button:hover {
  background: #113c7c;
}
pre {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  background: #edf3fc;
  border: 1px solid #a6bcdf;
  border-left: 6px solid #174c9b;
  padding: 16px 24px;
  min-height: 85px;
  font:
    15px/1.5 "Courier New",
    monospace;
  margin: 12px 0;
}
#status {
  margin: 15px 0 8px;
  font-size: 13px;
}
a {
  color: #174c9b;
}
footer {
  margin-top: 20px;
  border-top: 1px solid #8ca3c5;
  padding-top: 15px;
  font-size: 12px;
  color: #425879;
}
:focus-visible {
  outline: 3px solid #b76613;
  outline-offset: 3px;
}
@media (max-width: 550px) {
  main {
    padding: 16px;
  }
  h1 {
    font-size: 30px;
  }
  form {
    grid-template-columns: 1fr;
  }
  form > * {
    grid-column: 1 !important;
  }
}