html,body {
  height:100%;
  margin:0;
  color:var(--ink);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial;
  background:var(--background);
}

.wrap {
  display:grid;
  place-items:center;
  min-height:100dvh;
  padding:24px;
  gap:16px;
}

.card {
  background:var(--card-bg);
  border-radius:24px;
  box-shadow:0 12px 40px rgba(0,0,0,.08);
  padding:18px;
  max-width:min(900px, 92vw);
  width:100%;
}

header {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:4px 6px 12px;
}

h1 {
  font-size:clamp(18px, 2.4vw, 24px);
  margin:0;
  letter-spacing:.2px;
}

.btns {
  display:flex;
  gap:8px;
  flex-wrap:wrap;
}

button {
  appearance:none;
  border:0;
  background:var(--button-bg);
  color:var(--button-ink);
  padding:10px 14px;
  border-radius:999px;
  font-weight:600;
  cursor:pointer;
  box-shadow:0 2px 0 rgba(0,0,0,.05) inset;
  transition:transform .08s ease, filter .15s ease;
}
button:hover { filter:brightness(1.05); }
button:active { transform:translateY(1px) scale(.98); }

select {
  border:1px solid #ccc;
  border-radius:999px;
  padding:8px 12px;
  background:var(--button-bg);
  color:var(--button-ink);
  font-weight:600;
}

.canvas-wrap {
  position:relative;
  border-radius:20px;
  overflow:hidden;
  aspect-ratio:16 / 9;
  background:var(--canvas-bg);
}
canvas {
  display:block;
  width:100%;
  height:100%;
}

.hint {
  opacity:.7;
  font-size:13px;
  text-align:center;
}