body {
  flex-flow: row wrap;
  box-sizing: border-box;
  display: flex;
  place-content: center;
  align-items: center;
  flex: 1 1 100%;
  max-width: 100%;
  background-color: #303030;
  color: #fff;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
}

main {
  margin-top: 2em;
  width: 90%;
  max-width: 1000px;
  border-radius: 4px;
  padding: 1rem;
  background-color: #fff;
  color: rgba(0, 0, 0, 0.87);
}
main header {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
}
main header img {
  max-width: 250px;
}

input {
  line-height: 2.25rem;
  border-radius: 4px;
}
input[type="text"] {
  border: 1px solid #303030;
  padding: 0 0.5rem;
}
input[type="submit"] {
  border-width: 0;
  padding: 0 1rem;
  background-color: #2196f3;
  color: #fff;
  margin-top: 1rem;
  cursor: pointer;
}

.subtitle {
  font-size: 1.25rem;
}
.alert {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: 4px;
  background-color: #a02031;
  color: #fff;
}