:root {
  --bg: #fafaf7; --fg: #1d1d1b; --muted: #666; --line: #ddd; --acc: #c8451f; --acc2: #1f6fc8;
  --panel: #fff; --code: #f1f0ec;
}
* { box-sizing: border-box; }
html { font-size: 17px; }
body {
  margin: 0; background: var(--bg); color: var(--fg);
  font-family: -apple-system, "Segoe UI", Inter, Roboto, sans-serif; line-height: 1.5;
}
main { max-width: 1100px; margin: 0 auto; padding: 24px 20px 80px; }
h1 { font-size: 1.9rem; margin: 0 0 4px; }
h2 { font-size: 1.35rem; margin: 40px 0 10px; border-bottom: 2px solid var(--line); padding-bottom: 4px; }
h3 { font-size: 1.1rem; margin: 24px 0 6px; }
p, li { max-width: 72ch; }
code, pre { font-family: ui-monospace, Menlo, Consolas, monospace; font-size: 0.9em; }
code { background: var(--code); padding: 1px 5px; border-radius: 4px; }
pre { background: var(--code); padding: 12px 14px; border-radius: 6px; overflow-x: auto; line-height: 1.4; }
pre code { background: none; padding: 0; }
a { color: var(--acc2); }
.sub { color: var(--muted); margin: 0 0 20px; }
.nav { display: flex; gap: 14px; flex-wrap: wrap; font-size: 0.9rem; margin-bottom: 18px; }
.nav a { text-decoration: none; padding: 4px 10px; border: 1px solid var(--line); border-radius: 20px; background: var(--panel); }
.nav a.cur { border-color: var(--acc); color: var(--acc); }

/* demos */
.demo { background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 16px; margin: 18px 0; }
.demo .titulo { font-weight: 600; margin: 0 0 8px; }
.row { display: flex; gap: 18px; flex-wrap: wrap; align-items: flex-start; }
.col { display: flex; flex-direction: column; gap: 8px; }
.controls { display: flex; flex-direction: column; gap: 6px; min-width: 260px; }
.controls h4 { margin: 8px 0 2px; font-size: 0.85rem; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
.ctl { display: grid; grid-template-columns: 130px 1fr 56px; align-items: center; gap: 8px; font-size: 0.9rem; }
.ctl.chk { grid-template-columns: auto 1fr; }
.ctl .lbl { color: #333; }
.ctl .val { font-family: ui-monospace, Menlo, monospace; text-align: right; color: var(--acc); }
.ctl input[type=range] { width: 100%; }
.ctl select, .ctl input[type=number] { font: inherit; padding: 2px 6px; }
.btn { font: inherit; font-size: 0.9rem; padding: 6px 12px; border: 1px solid #bbb; background: #fff; border-radius: 6px; cursor: pointer; }
.btn:hover { border-color: var(--acc); color: var(--acc); }
.btn.prim { background: var(--acc); color: #fff; border-color: var(--acc); }
.btns { display: flex; gap: 8px; flex-wrap: wrap; }
canvas { border: 1px solid var(--line); border-radius: 6px; background: #fff; display: block; }
.legenda { font-size: 0.85rem; color: var(--muted); max-width: 60ch; }
.nota { border-left: 4px solid var(--acc2); background: #eef4fb; padding: 10px 14px; border-radius: 0 6px 6px 0; margin: 14px 0; }
.alerta { border-left: 4px solid var(--acc); background: #fbeee9; padding: 10px 14px; border-radius: 0 6px 6px 0; margin: 14px 0; }
.passo { border-left: 4px solid #999; padding-left: 12px; margin: 14px 0; }
.passo b { color: var(--acc); }
.grid2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 16px; }
.fig { text-align: center; font-size: 0.85rem; color: var(--muted); }
.fig canvas { margin: 0 auto 4px; }
.mono { font-family: ui-monospace, Menlo, monospace; font-size: 0.85rem; white-space: pre; background: var(--code); padding: 10px; border-radius: 6px; }
.kbd { font-family: ui-monospace, monospace; border: 1px solid #bbb; border-bottom-width: 2px; border-radius: 4px; padding: 0 5px; font-size: .85em; background: #fff; }
table { border-collapse: collapse; margin: 10px 0; font-size: 0.95rem; }
th, td { border: 1px solid var(--line); padding: 6px 10px; text-align: left; vertical-align: top; }
th { background: var(--code); }
.prox { margin-top: 40px; display: flex; justify-content: space-between; gap: 12px; }
.prox a { text-decoration: none; padding: 10px 14px; border: 1px solid var(--line); border-radius: 8px; background: var(--panel); }
@media (max-width: 700px) { .ctl { grid-template-columns: 100px 1fr 48px; } html { font-size: 15px; } }