body {
  font-family: system-ui, sans-serif;
  max-width: 640px;
  margin: 2rem auto;
  padding: 0 1rem;
  color: #1a1a1a;
}

header {
  margin-bottom: 2rem;
}

.subtitle {
  color: #666;
  font-size: 0.9rem;
}

section {
  margin-bottom: 2rem;
}

form,
#app-section > div {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-width: 360px;
  margin-bottom: 1rem;
}

label {
  display: flex;
  flex-direction: column;
  font-size: 0.9rem;
  gap: 0.25rem;
}

input {
  padding: 0.4rem;
  font-size: 1rem;
}

button {
  padding: 0.5rem;
  cursor: pointer;
}

#chat-log,
#file-list {
  list-style: none;
  padding: 0;
  border: 1px solid #ddd;
  border-radius: 4px;
  max-height: 200px;
  overflow-y: auto;
}

#chat-log li,
#file-list li {
  padding: 0.4rem 0.6rem;
  border-bottom: 1px solid #eee;
}