:root {
  color-scheme: light dark;
  --bg: #0f172a;
  --card: #111827;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --accent: #38bdf8;
  --border: #374151;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: linear-gradient(180deg, #020617, #0f172a);
  color: var(--text);
}

.hero {
  text-align: center;
  padding: 2rem 1rem 1rem;
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.8rem, 3vw, 2.8rem);
}

.hero p {
  color: var(--muted);
}

.container {
  width: min(1100px, 92%);
  margin: 0 auto;
  display: grid;
  gap: 1rem;
}

.controls,
.io-grid article,
.status,
.seo-content {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1rem;
  background: color-mix(in srgb, var(--card) 88%, transparent);
}

.controls {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 0.75rem;
}

label {
  display: grid;
  gap: 0.35rem;
  font-size: 0.9rem;
}

select,
textarea,
button {
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #0b1220;
  color: var(--text);
  padding: 0.6rem 0.75rem;
}

textarea {
  width: 100%;
  min-height: 220px;
  resize: vertical;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  line-height: 1.4;
}

.io-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.actions {
  margin-top: 0.75rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

button,
.file-upload {
  cursor: pointer;
  transition: transform 0.12s ease, border-color 0.12s ease;
}

button:hover,
.file-upload:hover {
  transform: translateY(-1px);
  border-color: var(--accent);
}

.file-upload {
  position: relative;
  display: inline-flex;
  align-items: center;
  padding: 0.6rem 0.75rem;
  border-radius: 10px;
  border: 1px solid var(--border);
}

.file-upload input {
  display: none;
}

.checkbox-line {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  grid-column: 1 / -1;
}

.status {
  min-height: 44px;
  color: #d1fae5;
}

.status.error {
  color: #fecaca;
}

.seo-content li {
  margin-bottom: 0.35rem;
}

footer {
  text-align: center;
  padding: 1rem;
  color: var(--muted);
}

@media (max-width: 900px) {
  .io-grid {
    grid-template-columns: 1fr;
  }
}