:root {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --text: #101828;
  --border: #d0d5dd;
  --error: #b42318;
  --ok: #027a48;
  --neutral: #175cd3;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", Tahoma, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.app {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 1rem;
  padding: 1rem;
}

.controls,
.matrices article {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.9rem;
}

.controls h1,
.matrices h2 { margin-top: 0; }

.dims {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
  margin-bottom: 0.7rem;
}

label {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  font-size: 0.9rem;
}

input,
select,
button {
  border-radius: 8px;
  border: 1px solid var(--border);
  padding: 0.5rem;
  font-size: 0.95rem;
}

button {
  margin-top: 0.5rem;
  background: #175cd3;
  color: #fff;
  border-color: #175cd3;
  cursor: pointer;
}

.matrices {
  display: grid;
  grid-template-columns: repeat(3, minmax(220px, 1fr));
  gap: 0.8rem;
}

.grid {
  display: grid;
  gap: 0.35rem;
}

.grid input {
  text-align: center;
  min-width: 0;
}

.result {
  min-height: 120px;
  overflow: auto;
  border: 1px dashed var(--border);
  border-radius: 8px;
  padding: 0.6rem;
}

.status {
  margin-top: 0.8rem;
  padding: 0.6rem;
  border-radius: 8px;
  border: 1px solid transparent;
}

.status.neutral { background: #eef4ff; border-color: #c8dbff; color: var(--neutral); }
.status.error { background: #fef3f2; border-color: #fecdca; color: var(--error); }
.status.success { background: #ecfdf3; border-color: #abefc6; color: var(--ok); }

@media (max-width: 980px) {
  .app { grid-template-columns: 1fr; }
  .matrices { grid-template-columns: 1fr; }
}