:root {
  --bg: #0b0d10;
  --bg-elevated: #14171c;
  --border: #262b33;
  --text: #e6e8eb;
  --text-dim: #8a919c;
  --accent: #7dd3fc;
  --accent-strong: #38bdf8;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  min-height: 100%;
}

body {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2.5rem 1.25rem 4rem;
}

.hero {
  text-align: center;
  margin-bottom: 2rem;
}

.hero h1 {
  font-family: var(--mono);
  font-size: clamp(2rem, 5vw, 3rem);
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
  background: linear-gradient(120deg, var(--text) 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.tagline {
  color: var(--text-dim);
  margin: 0;
  font-size: 1.05rem;
}

main {
  width: 100%;
  max-width: 900px;
}

.drop-zone {
  border: 2px dashed var(--border);
  border-radius: 16px;
  background: var(--bg-elevated);
  padding: 3rem 1.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.drop-zone:hover,
.drop-zone.dragover {
  border-color: var(--accent-strong);
  background: #171b21;
}

.drop-zone__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--text-dim);
}

.drop-zone__icon {
  width: 40px;
  height: 40px;
  color: var(--accent);
  margin-bottom: 0.25rem;
}

.drop-zone__inner strong {
  color: var(--text);
}

.drop-zone__hint {
  font-size: 0.85rem;
  margin-top: 0.25rem;
}

.workspace {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  align-items: flex-end;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem 1.25rem;
}

.control {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.control span {
  font-weight: 500;
}

.control input[type="range"] {
  accent-color: var(--accent-strong);
  width: 160px;
}

.control select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.35rem 0.5rem;
  font-family: inherit;
}

.control output {
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.8rem;
}

.control--checkbox {
  flex-direction: row;
  align-items: center;
  gap: 0.5rem;
}

.control--checkbox input {
  accent-color: var(--accent-strong);
  width: 16px;
  height: 16px;
}

.control--checkbox span {
  color: var(--text);
}

.output-frame {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #000;
  overflow: auto;
  max-height: 70vh;
  padding: 1rem;
}

.output-frame.light-bg {
  background: #f5f5f0;
}

#ascii-output {
  margin: 0;
  font-family: var(--mono);
  line-height: 1;
  font-size: 8px;
  white-space: pre;
  width: fit-content;
}

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

.btn {
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 500;
  padding: 0.6rem 1.1rem;
  border-radius: 8px;
  border: 1px solid var(--accent-strong);
  background: var(--accent-strong);
  color: #051018;
  cursor: pointer;
  transition: opacity 0.15s ease;
}

.btn:hover {
  opacity: 0.85;
}

.btn--ghost {
  background: transparent;
  color: var(--text-dim);
  border-color: var(--border);
}

.btn--ghost:hover {
  color: var(--text);
  border-color: var(--text-dim);
}

footer {
  margin-top: 3rem;
  color: var(--text-dim);
  font-size: 0.8rem;
  text-align: center;
}

footer a {
  color: var(--text-dim);
}
footer a:hover {
  color: var(--accent);
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f7f7f5;
    --bg-elevated: #ffffff;
    --border: #e2e2df;
    --text: #14171c;
    --text-dim: #6b7280;
  }
  .output-frame { background: #000; }
}