:root {
  --bg: #f6f7f9;
  --fg: #1f2328;
  --muted: #59636e;
  --accent: #0969da;
  --border: #d0d7de;
  --panel: #ffffff;
  --error: #cf222e;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0d1117;
    --fg: #e6edf3;
    --muted: #9198a1;
    --accent: #58a6ff;
    --border: #3d444d;
    --panel: #161b22;
    --error: #ff7b72;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #0d1117;
  --fg: #e6edf3;
  --muted: #9198a1;
  --accent: #58a6ff;
  --border: #3d444d;
  --panel: #161b22;
  --error: #ff7b72;
  color-scheme: dark;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--fg);
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
}
h1 { margin: 0; font-size: 1.25rem; }
h1 small { margin-left: .5em; font-size: .8rem; font-weight: normal; color: var(--muted); }

main { max-width: 640px; margin: 0 auto; padding: 24px 16px; }

#drop {
  padding: 32px 16px;
  text-align: center;
  background: var(--panel);
  border: 2px dashed var(--border);
  border-radius: 12px;
  transition: border-color .15s;
}
#drop.dragover { border-color: var(--accent); }
#drop p { margin: 0 0 12px; }
#drop .lead { font-weight: 600; }
#drop .hint { color: var(--muted); font-size: .9rem; }
#drop p:last-child { margin: 0; }
code { font-size: .95em; }

button {
  font: inherit;
  padding: 6px 14px;
  color: var(--fg);
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 6px;
  cursor: pointer;
}
button:hover { border-color: var(--accent); }
#theme { font-size: 1.1rem; line-height: 1; padding: 6px 10px; }

.options {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  align-items: center;
  margin-top: 16px;
}
.options label { display: flex; align-items: center; gap: 6px; }

#status { margin: 16px 0 0; color: var(--muted); overflow-wrap: anywhere; }
#status.error { color: var(--error); }

dialog {
  width: min(90vw, 640px);
  max-height: 85vh;
  padding: 16px 20px;
  color: var(--fg);
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
}
dialog::backdrop { background: rgba(0, 0, 0, .5); }
dialog h2 { margin: 8px 0; font-size: 1rem; }
dialog pre {
  max-height: 30vh;
  margin: 0 0 12px;
  padding: 8px 12px;
  overflow: auto;
  font-size: .85rem;
  background: var(--bg);
  border-radius: 6px;
}
dialog form { margin: 0; text-align: right; }