* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  background: #ececec;
  color: #222;
}

.panel {
  max-width: 360px;
  margin: 24px auto;
  padding: 16px;
  background: #fff;
  border: 1px solid #bdbdbd;
}

h1 {
  margin: 0 0 8px;
  font-size: 1.25rem;
}

h2 {
  margin: 16px 0 8px;
  font-size: 1rem;
}

.hint {
  margin: 0 0 16px;
  font-size: 0.85rem;
  color: #555;
  line-height: 1.4;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.field input,
.field select {
  padding: 8px 10px;
  border: 1px solid #999;
  font-size: 1rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
  margin: 16px 0 8px;
}

.num-btn {
  aspect-ratio: 1;
  border: 1px solid #888;
  background: #fff;
  font-size: 1rem;
  cursor: pointer;
}

.num-btn.selected {
  background: #1a4f9c;
  color: #fff;
  border-color: #1a4f9c;
}

.num-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.selection {
  margin: 8px 0 16px;
  font-weight: 600;
}

.send {
  width: 100%;
  padding: 12px;
  margin-bottom: 8px;
  border: none;
  background: #f5c400;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
}

.clear {
  width: 100%;
  padding: 10px;
  margin-bottom: 8px;
  border: 1px solid #888;
  background: #f5f5f5;
  cursor: pointer;
}

.settings {
  margin-top: 20px;
  padding-top: 12px;
  border-top: 1px solid #ddd;
}

#saveExtId {
  padding: 8px 12px;
  border: 1px solid #888;
  background: #f5f5f5;
  cursor: pointer;
}

.log {
  margin-top: 16px;
  padding: 10px;
  min-height: 72px;
  background: #f7f7f7;
  border: 1px solid #ddd;
  font-size: 0.8rem;
  white-space: pre-wrap;
  word-break: break-word;
}