* { box-sizing: border-box; }

body {
  font-family: system-ui, sans-serif;
  color: #111;
  background: #fff;
  margin: 0;
  padding: 2rem 1rem calc(4rem + env(safe-area-inset-bottom, 0px));
}

main {
  max-width: 70rem;
  margin: 0 auto;
}

h1 {
  font-size: 1.4rem;
  font-weight: 600;
  letter-spacing: .35em;
  text-transform: uppercase;
  margin: 0 0 2rem;
}

.layout {
  display: grid;
  grid-template-columns: 22rem 1fr;
  gap: 3rem;
  align-items: start;
}

@media (max-width: 56rem) {
  .layout { grid-template-columns: 1fr; }
}

.panel-title {
  display: block;
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: #888;
  margin-bottom: .25rem;
}

.hint {
  font-size: .8rem;
  color: #888;
  margin: 0 0 .75rem;
}

textarea {
  width: 100%;
  min-height: 24rem;
  padding: .75rem;
  font: inherit;
  font-size: .9rem;
  line-height: 1.7;
  color: #111;
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 4px;
  resize: vertical;
}

textarea:focus, input:focus {
  outline: none;
  border-color: #111;
}

input {
  font: inherit;
  font-size: .9rem;
  padding: .45rem .65rem;
  border: 1px solid #ddd;
  border-radius: 4px;
  width: 9rem;
}

.row {
  display: flex;
  align-items: center;
  gap: .6rem;
  margin-top: .75rem;
  flex-wrap: wrap;
}

.controls { margin-top: 0; margin-bottom: 1rem; }

.inline-label {
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: #888;
}

.btn {
  font: inherit;
  font-size: .85rem;
  padding: .45rem 1.1rem;
  background: #fff;
  color: #111;
  border: 1px solid #111;
  border-radius: 4px;
  cursor: pointer;
  transition: background .15s, color .15s;
}

.btn:hover:not(:disabled) { background: #111; color: #fff; }

.btn:disabled { opacity: .35; cursor: default; }

.status { font-size: .8rem; color: #888; }

.card-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  border: 2px solid #111;
  max-width: 40rem;
}

.cell {
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: .9rem .6rem;
  min-height: 6.2rem;
  font-size: .85rem;
  line-height: 1.45;
  border: 1px solid #ddd;
  margin: -0.5px;
  word-break: break-word;
}

.cell.free {
  font-weight: 600;
  letter-spacing: .15em;
  text-transform: uppercase;
  background: #f5f5f5;
}

@media (max-width: 34rem) {
  body { padding-top: 1.25rem; padding-inline: .75rem; }
  h1 { margin-bottom: 1.5rem; }
  .layout { gap: 2rem; }
  /* 16px+ so iOS Safari doesn't zoom into focused inputs */
  textarea, input { font-size: 1rem; }
  textarea { min-height: 10rem; }
  input { flex: 1 1 8rem; width: auto; }
  .btn { padding: .6rem 1.2rem; }
  .cell { min-height: 5rem; font-size: .78rem; padding: .6rem .4rem; }
}

@media (max-width: 24rem) {
  .btn { flex: 1 1 100%; text-align: center; }
}