:root {
  --bg: #f5f7fb; --card: #fff; --text: #111827; --muted: #6b7280; --line: #e5e7eb;
  --brand: #0b5cff; --brand-ink: #fff; --ok: #0a7d38; --warn: #b45309; --bad: #b91c1c; --soft: #eef3ff;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #0d1117; --card: #161b22; --text: #e6edf3; --muted: #8b949e; --line: #30363d;
    --brand: #4c8dff; --ok: #3fb950; --warn: #d29922; --bad: #f85149; --soft: #1c2533; }
}
* { box-sizing: border-box; min-width: 0; }
[hidden] { display: none !important; }
body { margin: 0; font: 16px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; background: var(--bg); color: var(--text);
  padding: env(safe-area-inset-top) 0 env(safe-area-inset-bottom); -webkit-tap-highlight-color: transparent; }
main, header.top, footer, .banner { max-width: 640px; margin: 0 auto; padding: 0 16px; }
header.top { padding-top: 20px; }
h1 { font-size: 1.5rem; margin: 0 0 4px; }
h2 { font-size: 1.1rem; margin: 0 0 12px; }
h3 { font-size: 1rem; margin: 16px 0 8px; }
.pad { padding: 0 4px; margin-top: 24px; }
.muted { color: var(--muted); }
.small { font-size: .85rem; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 16px; margin: 14px 0; }
.banner { background: #fff4d6; color: #5c4400; border-radius: 10px; padding: 10px 14px; margin-top: 12px; font-size: .9rem; }
@media (prefers-color-scheme: dark) { .banner { background: #3a2f0b; color: #f5d77a; } }
label { display: block; font-size: .85rem; color: var(--muted); }
input, select { display: block; width: 100%; margin-top: 4px; font: inherit; font-size: 16px; color: var(--text); background: var(--bg);
  border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; min-height: 44px; }
input:focus, select:focus { outline: 2px solid var(--brand); outline-offset: 1px; }
input[type=checkbox], input[type=radio] { display: inline; width: auto; min-height: 0; margin: 0 6px 0 0; }
.grid2 { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; margin: 12px 0; }
.grid4 { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; margin: 12px 0; }
@media (max-width: 480px) { .grid4 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.seg { display: flex; gap: 6px; background: var(--bg); border-radius: 12px; padding: 4px; width: fit-content; }
.seg label { color: var(--text); padding: 8px 14px; border-radius: 9px; cursor: pointer; font-size: .95rem; }
.seg label:has(input:checked) { background: var(--card); box-shadow: 0 1px 3px rgba(0,0,0,.12); font-weight: 600; }
.seg input { position: absolute; opacity: 0; }
details { margin: 8px 0; }
summary { cursor: pointer; color: var(--brand); font-size: .95rem; padding: 6px 0; }
fieldset.airlines { border: 1px solid var(--line); border-radius: 10px; display: flex; flex-wrap: wrap; gap: 6px 14px; }
fieldset.airlines label { color: var(--text); font-size: .95rem; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; border: 0; border-radius: 10px; padding: 11px 16px;
  background: var(--brand); color: var(--brand-ink); font: inherit; font-weight: 600; cursor: pointer; text-decoration: none; min-height: 44px; }
.btn.sec { background: var(--soft); color: var(--brand); }
.btn.link, button.link { background: none; color: var(--brand); padding: 6px 8px; min-height: 0; border: 0; font: inherit; cursor: pointer; }
.btn.small { padding: 8px 12px; min-height: 36px; font-size: .9rem; }
.btn.big { width: 100%; margin-top: 16px; padding: 14px; font-size: 1.05rem; }
.btn:disabled { opacity: .55; cursor: default; }
@media (hover: hover) { .btn:hover { filter: brightness(1.07); } }
.row { display: flex; gap: 10px; align-items: center; }
.row.wrap { flex-wrap: wrap; }
.row.between { justify-content: space-between; }
.row.end { align-items: flex-end; margin-top: 10px; }
.route { font-weight: 700; font-size: 1.1rem; }
.now { font-size: 1.5rem; font-weight: 800; letter-spacing: -.01em; }
.now.ok { color: var(--ok); }
.alert.paused { opacity: .6; }
.spark { width: 120px; height: 36px; flex: none; }
.spark polyline { fill: none; stroke: var(--brand); stroke-width: 2; vector-effect: non-scaling-stroke; }
.spark line { stroke: var(--ok); stroke-dasharray: 3 3; vector-effect: non-scaling-stroke; }
ul.offers, ul.opts { list-style: none; padding: 0; margin: 10px 0 0; }
ul.offers li { border-top: 1px solid var(--line); padding: 8px 0; display: flex; justify-content: space-between; gap: 10px; align-items: center; font-size: .9rem; }
ul.offers a { white-space: nowrap; font-weight: 600; color: var(--brand); text-decoration: none; }
.switch { position: relative; width: 46px; height: 28px; flex: none; }
.switch input { opacity: 0; width: 0; height: 0; }
.switch span { position: absolute; inset: 0; background: var(--line); border-radius: 28px; transition: background .2s; cursor: pointer; }
.switch span::before { content: ""; position: absolute; width: 22px; height: 22px; left: 3px; top: 3px; background: #fff; border-radius: 50%; transition: transform .2s; }
.switch input:checked + span { background: var(--ok); }
.switch input:checked + span::before { transform: translateX(18px); }
.err { color: var(--bad); }
.ok { color: var(--ok); }
.warn { color: var(--warn); }
footer { padding-top: 8px; padding-bottom: 32px; }
code { font-size: .85em; }
/* Página /go */
main.go { padding-top: 24px; padding-bottom: 40px; }
.brand { color: var(--muted); text-decoration: none; font-size: .9rem; }
.price { font-size: 2.4rem; font-weight: 800; margin: 8px 0 4px; }
main.go form .btn, main.go > .btn, main.go > form .btn { width: 100%; margin: 8px 0; padding: 14px; font-size: 1.05rem; }
ul.opts li { border-top: 1px solid var(--line); padding: 10px 0; }
ul.opts li .btn { width: 100%; margin-top: 6px; }
.tag { font-size: .72rem; background: var(--soft); color: var(--brand); padding: 2px 6px; border-radius: 6px; }
.tag.warn { color: var(--warn); }

label.check { color: var(--text); font-size: .9rem; margin-top: 10px; display: flex; gap: 8px; align-items: flex-start; }
label.check input { margin-top: 3px; }

details.notices { margin-top: 10px; }
details.notices summary { font-size: .9rem; }
details.notices li { border-top: 1px solid var(--line); padding: 8px 0; display: flex; justify-content: space-between; gap: 10px; align-items: center; font-size: .9rem; }
details.notices ul { list-style: none; padding: 0; margin: 6px 0 0; }
details.notices a { white-space: nowrap; font-weight: 600; color: var(--brand); text-decoration: none; }