:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #6b6b6b;
  --line: #e0e0e0;
  --panel: #fafafa;
  --accent: #2b6cb0;
  --accent-fg: #ffffff;
  --error: #b02b2b;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16181c;
    --fg: #e8e8e8;
    --muted: #9aa0a6;
    --line: #2e3238;
    --panel: #1c1f24;
    --accent: #6aa9e9;
    --accent-fg: #10131a;
    --error: #e88;
  }
}

* {
  box-sizing: border-box;
}

/* the rules below set a display, which would otherwise reveal hidden elements */
[hidden] {
  display: none !important;
}

body {
  margin: 0;
  padding: 2rem 1.5rem 4rem;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
}

header,
main {
  max-width: 1100px;
  margin: 0 auto;
}

h1 {
  margin: 0 0 0.25rem;
  font-size: 1.6rem;
  letter-spacing: -0.01em;
}

.lede {
  margin: 0 0 2rem;
  color: var(--muted);
  max-width: 55ch;
}

main {
  display: grid;
  grid-template-columns: minmax(260px, 320px) 1fr;
  gap: 2rem;
  align-items: start;
}

@media (max-width: 800px) {
  main {
    grid-template-columns: 1fr;
  }
}

fieldset {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  padding: 0.75rem 1rem 1rem;
  margin: 0 0 1rem;
}

legend {
  padding: 0 0.4rem;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
}

label {
  display: block;
  margin-top: 0.85rem;
  font-size: 0.9rem;
  font-weight: 500;
}

label:first-of-type {
  margin-top: 0.25rem;
}

input[type="number"],
input[type="text"],
select {
  display: block;
  width: 100%;
  margin-top: 0.3rem;
  padding: 0.4rem 0.5rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--bg);
  color: var(--fg);
  font: inherit;
  font-size: 0.9rem;
}

input:focus-visible,
select:focus-visible,
button:focus-visible,
.drop:focus-within {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

small {
  display: block;
  margin-top: 0.3rem;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 400;
}

code {
  font-size: 0.9em;
}

.drop {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 5rem;
  padding: 1rem;
  border: 1px dashed var(--line);
  border-radius: 6px;
  text-align: center;
  color: var(--muted);
  font-weight: 400;
  cursor: pointer;
}

.drop.dragover {
  border-color: var(--accent);
  color: var(--accent);
}

.drop input {
  display: none;
}

button {
  width: 100%;
  padding: 0.6rem;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: var(--accent-fg);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.status {
  padding: 0.6rem 0.8rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel);
  color: var(--muted);
  font-size: 0.85rem;
  font-variant-numeric: tabular-nums;
}

.status.error {
  color: var(--error);
  border-color: var(--error);
}

.preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 1rem;
}

@media (max-width: 560px) {
  .preview {
    grid-template-columns: 1fr;
  }
}

figure {
  margin: 0;
}

figcaption {
  margin-bottom: 0.4rem;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.preview img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid var(--line);
  border-radius: 6px;
}

.placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  aspect-ratio: 4 / 3;
  border: 1px dashed var(--line);
  border-radius: 6px;
  color: var(--muted);
  font-size: 0.85rem;
}

.download {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--accent);
  border-radius: 6px;
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 600;
  text-decoration: none;
}