/* Simple, clean design */
:root{
  --bg:#0f1115;
  --panel:#171922;
  --text:#e8eaf0;
  --muted:#9aa3b2;
  --accent:#2dd4bf;
  --accent-weak:#164e63;
  --border:#222633;
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Apple Color Emoji","Segoe UI Emoji";
}
.container{
  max-width:820px;
  margin:0 auto;
  padding:24px 16px 40px;
}
h1{
  font-size:1.4rem;
  font-weight:700;
  margin:0 0 16px;
}
.controls{
  display:grid;
  gap:16px;
  grid-template-columns: 1fr;
  background:var(--panel);
  border:1px solid var(--border);
  border-radius:12px;
  padding:16px;
}
.size, .density, .output-label{
  display:grid;
  gap:8px;
}
.size-inputs{
  display:flex;
  align-items:center;
  gap:8px;
}
.size-inputs input{
  width:90px;
}
input[type="number"], textarea{
  background:#0c0e13;
  border:1px solid var(--border);
  color:var(--text);
  border-radius:8px;
  padding:10px 12px;
  outline:none;
}
input[type="number"]:focus, textarea:focus{
  border-color:var(--accent);
  box-shadow:0 0 0 3px color-mix(in oklab, var(--accent) 25%, transparent);
}
.x{color:var(--muted); user-select:none}
.density{
  align-items:center;
  grid-template-columns: auto 1fr auto;
}
.density input[type="range"]{
  width:100%;
}
#densityOut{
  font-variant-numeric:tabular-nums;
  color:var(--muted);
}
.buttons{
  display:flex;
  gap:8px;
  flex-wrap:wrap;
}
button{
  appearance:none;
  border:1px solid var(--accent);
  background:linear-gradient(180deg, color-mix(in oklab, var(--accent) 18%, transparent), transparent);
  color:var(--text);
  padding:10px 14px;
  border-radius:10px;
  cursor:pointer;
  font-weight:600;
}
button.secondary{
  border-color:var(--border);
  background:#0c0e13;
}
button:active{transform:translateY(1px)}
textarea{
  width:100%;
  min-height:220px;
  resize:vertical;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  line-height:1.45;
}
.hint{
  color:var(--muted);
  font-size:.9rem;
  margin-top:10px;
}
@media (min-width:760px){
  .controls{
    grid-template-columns: 1fr 1fr auto;
    align-items:end;
  }
  .density{
    grid-column: span 2;
  }
  .buttons{
    justify-content:flex-end;
  }
}