* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: #f4f5f7;
  color: #1f2933;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: #fff;
  border-bottom: 1px solid #e1e4e8;
}

h1 {
  margin: 0;
  font-size: 1.4rem;
  letter-spacing: 0.02em;
}

button {
  font: inherit;
  padding: 0.55rem 1.1rem;
  border: 1px solid #2f855a;
  background: #38a169;
  color: #fff;
  border-radius: 6px;
  cursor: pointer;
}

button:hover { background: #2f855a; }
button:active { transform: translateY(1px); }

main {
  max-width: 720px;
  margin: 1.5rem auto;
  padding: 0 1rem;
}

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

.cell {
  aspect-ratio: 1 / 1;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 6px;
  font-size: 0.8rem;
  line-height: 1.2;
  background: #fff;
  border: 1px solid #d2d6dc;
  border-radius: 6px;
  cursor: pointer;
  user-select: none;
  overflow: hidden;
  transition: background 0.12s ease;
}

.cell:hover { border-color: #38a169; }

.cell.marked {
  background: #c6f6d5; /* light green */
  border-color: #9ae6b4;
}

.status {
  margin-top: 1rem;
  font-size: 0.85rem;
  color: #616e7c;
  min-height: 1.2em;
}

.editor {
  margin-top: 2rem;
  padding-top: 1.25rem;
  border-top: 1px solid #e1e4e8;
}

.editor h2 {
  margin: 0 0 0.75rem;
  font-size: 1.05rem;
}

.add-form {
  display: flex;
  gap: 8px;
  margin-bottom: 1rem;
}

.add-form input {
  flex: 1;
  font: inherit;
  padding: 0.5rem 0.65rem;
  border: 1px solid #d2d6dc;
  border-radius: 6px;
}

.phrase-list {
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 320px;
  overflow-y: auto;
}

.phrase-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 0.4rem 0.6rem;
  border-bottom: 1px solid #eef0f2;
  font-size: 0.85rem;
}

.phrase-list li button {
  padding: 0.15rem 0.5rem;
  background: #fff;
  color: #c53030;
  border-color: #feb2b2;
  line-height: 1;
}

.phrase-list li button:hover {
  background: #fff5f5;
}

@media (max-width: 520px) {
  .cell { font-size: 0.65rem; }
}