/* =============================================================
   1. Tokens
   ============================================================= */
:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --surface-2: #eef1f8;
  --border: #dfe4ee;
  --text: #101c34;
  --text-muted: #5b6a89;
  --primary: #0b3d91;
  --primary-dark: #082a68;
  --primary-tint: #e7edfb;
  --accent: #ff6a45;
  --accent-dark: #e0512e;
  --cheap: #16a34a;
  --mid: #f59e0b;
  --expensive: #ef4444;
  --danger: #dc2626;
  --radius-lg: 18px;
  --radius: 12px;
  --radius-sm: 8px;
  --shadow-sm: 0 2px 8px rgba(16, 28, 52, 0.06);
  --shadow: 0 10px 30px rgba(16, 28, 52, 0.10);
  --shadow-lg: 0 20px 48px rgba(16, 28, 52, 0.18);
  --font-sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-display: "Manrope", var(--font-sans);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --header-h: 68px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0a1122;
    --surface: #111a30;
    --surface-2: #172140;
    --border: #263355;
    --text: #eef2fb;
    --text-muted: #93a1c4;
    --primary: #5b8dff;
    --primary-dark: #cddcff;
    --primary-tint: #16204a;
    --accent: #ff8562;
    --accent-dark: #ffab8f;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.35);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.55);
  }
}

/* =============================================================
   2. Reset & base
   ============================================================= */
*, *::before, *::after { box-sizing: border-box; margin: 0; }
html { -webkit-text-size-adjust: 100%; tab-size: 2; scroll-behavior: smooth; overflow-x: clip; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
  overscroll-behavior-y: none;
}
img, svg, video { display: block; max-width: 100%; }
img { height: auto; }
button { font: inherit; color: inherit; cursor: pointer; border: 0; background: none; }
a { color: inherit; text-decoration: none; }
input, select, textarea { font: inherit; color: inherit; }
p { text-wrap: pretty; }
h1, h2, h3, h4 { font-family: var(--font-display); text-wrap: balance; line-height: 1.12; letter-spacing: -0.02em; font-weight: 800; }
ul { list-style: none; padding: 0; }
::selection { background: var(--accent); color: #fff; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }

/* =============================================================
   3. Utilities
   ============================================================= */
.skip-link {
  position: fixed; top: -100px; left: 1rem; z-index: 9999;
  padding: .6rem 1rem; background: var(--primary); color: #fff;
  border-radius: var(--radius-sm); font-weight: 600;
  transition: top .2s var(--ease-out);
}
.skip-link:focus { top: 1rem; }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
.is-hidden { display: none !important; }
.container { width: 100%; max-width: 1120px; margin-inline: auto; padding-inline: 1.25rem; }
.section { padding-block: 3rem; }
.section-head { max-width: 640px; margin-bottom: 1.75rem; }
.section-head .eyebrow { color: var(--accent); font-weight: 700; font-size: .8rem; letter-spacing: .06em; text-transform: uppercase; }
.section-head h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); margin-top: .35rem; }
.section-head p { color: var(--text-muted); margin-top: .5rem; }
.muted { color: var(--text-muted); }
.center { text-align: center; margin-inline: auto; }

/* =============================================================
   4. Typography
   ============================================================= */
h1 { font-size: clamp(2rem, 4.6vw, 3rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: 1.15rem; }
.lead { font-size: 1.1rem; color: var(--text-muted); }

/* =============================================================
   5. Components
   ============================================================= */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5rem;
  padding: .8rem 1.4rem; border-radius: 999px; font-weight: 700; font-size: .95rem;
  transition: transform .18s var(--ease-out), box-shadow .18s var(--ease-out), background .18s var(--ease-out);
  white-space: nowrap;
}
.btn-primary { background: var(--accent); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: var(--accent-dark); transform: translateY(-1px); box-shadow: var(--shadow); }
.btn-secondary { background: var(--surface); color: var(--primary); border: 1px solid var(--border); }
.btn-secondary:hover { border-color: var(--primary); transform: translateY(-1px); }
.btn-ghost { color: var(--primary); font-weight: 600; }
.btn-ghost:hover { text-decoration: underline; }
.btn-block { width: 100%; }
.btn[disabled] { opacity: .6; pointer-events: none; }

.card {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.field { display: flex; flex-direction: column; gap: .35rem; min-width: 0; }
.field label { font-size: .78rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; letter-spacing: .04em; }
.field input, .field select {
  padding: .7rem .8rem; border-radius: var(--radius-sm); border: 1.5px solid var(--border);
  background: var(--surface); color: var(--text); width: 100%;
  transition: border-color .15s var(--ease-out);
}
.field input:focus, .field select:focus { border-color: var(--primary); }
.field-check { display: flex; align-items: center; gap: .5rem; font-size: .85rem; color: var(--text-muted); }
.field-check input { width: 1rem; height: 1rem; }

.badge {
  display: inline-flex; align-items: center; gap: .3rem; padding: .25rem .6rem;
  border-radius: 999px; font-size: .72rem; font-weight: 700; letter-spacing: .02em;
}
.badge-cheap { background: color-mix(in srgb, var(--cheap) 16%, transparent); color: var(--cheap); }
.badge-accent { background: color-mix(in srgb, var(--accent) 16%, transparent); color: var(--accent-dark); }
.badge-demo { background: var(--surface-2); color: var(--text-muted); border: 1px dashed var(--border); }

details.faq-item { border-bottom: 1px solid var(--border); padding-block: .9rem; }
details.faq-item summary { cursor: pointer; font-weight: 700; display: flex; justify-content: space-between; gap: 1rem; list-style: none; }
details.faq-item summary::-webkit-details-marker { display: none; }
details.faq-item summary::after { content: "+"; font-size: 1.3rem; color: var(--accent); flex-shrink: 0; }
details.faq-item[open] summary::after { content: "\2212"; }
details.faq-item p { margin-top: .6rem; color: var(--text-muted); }

/* =============================================================
   6. Sections
   ============================================================= */

/* --- Header --- */
.site-header {
  position: sticky; top: 0; z-index: 50; height: var(--header-h);
  display: flex; align-items: center; background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.logo { display: flex; align-items: center; gap: .5rem; font-family: var(--font-display); font-weight: 800; font-size: 1.15rem; color: var(--text); }
.logo svg { width: 26px; height: 26px; color: var(--accent); }
.main-nav { display: none; align-items: center; gap: 1.6rem; font-weight: 600; font-size: .92rem; }
.main-nav a { color: var(--text-muted); transition: color .15s; }
.main-nav a:hover, .main-nav a[aria-current="page"] { color: var(--primary); }
.header-actions { display: flex; align-items: center; gap: .6rem; }
.nav-toggle { display: inline-flex; padding: .5rem; border-radius: var(--radius-sm); }
.nav-toggle svg { width: 22px; height: 22px; }
.mobile-nav {
  display: none; flex-direction: column; gap: .2rem; background: var(--surface);
  border-bottom: 1px solid var(--border); padding: .5rem 1.25rem 1rem;
}
.mobile-nav.is-open { display: flex; }
.mobile-nav a { padding: .6rem 0; font-weight: 600; border-bottom: 1px solid var(--border); }
.mobile-nav a:last-child { border-bottom: 0; }

/* --- Hero + tool card --- */
.hero { padding-block: 2.4rem 1.5rem; }
.hero .container { text-align: center; }
.hero h1 { max-width: 20ch; margin-inline: auto; }
.hero .lead { max-width: 46ch; margin: .8rem auto 0; }

.tool-card { padding: 1.4rem; margin-top: 1.75rem; }
.trip-toggle { display: flex; gap: .5rem; margin-bottom: 1rem; }
.trip-toggle button {
  padding: .5rem 1rem; border-radius: 999px; font-weight: 700; font-size: .85rem;
  border: 1.5px solid var(--border); color: var(--text-muted);
}
.trip-toggle button[aria-pressed="true"] { background: var(--primary-tint); color: var(--primary); border-color: var(--primary); }

.search-form { display: grid; grid-template-columns: repeat(2, 1fr); gap: .9rem; }
.search-form .field-dates { display: grid; grid-template-columns: 1fr 1fr; gap: .9rem; }
.search-form .field-swap-wrap { display: flex; align-items: flex-end; }
.search-form .field-currency { grid-column: 1 / -1; }
.search-actions { grid-column: 1 / -1; display: flex; gap: .75rem; flex-wrap: wrap; align-items: center; justify-content: space-between; margin-top: .3rem; }
.origin-destination { display: grid; grid-template-columns: 1fr auto 1fr; gap: .5rem; align-items: end; grid-column: 1 / -1; }
.swap-btn {
  width: 42px; height: 42px; border-radius: 50%; border: 1.5px solid var(--border);
  display: inline-flex; align-items: center; justify-content: center; color: var(--primary);
  transition: transform .2s var(--ease-out), background .2s var(--ease-out);
}
.swap-btn:hover { background: var(--primary-tint); transform: rotate(180deg); }
.swap-btn svg { width: 18px; height: 18px; }

.tool-meta { display: flex; flex-wrap: wrap; gap: .6rem 1.2rem; align-items: center; margin-top: 1rem; font-size: .84rem; color: var(--text-muted); }
.tool-meta .privacy { display: inline-flex; align-items: center; gap: .4rem; }
.tool-meta svg { width: 16px; height: 16px; flex-shrink: 0; }

/* --- Ad slots --- */
.ad-slot {
  border: 1.5px dashed var(--border); border-radius: var(--radius); background: var(--surface-2);
  display: flex; align-items: center; justify-content: center; color: var(--text-muted);
  font-size: .78rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase;
  margin-block: 1.4rem;
}
.ad-slot span { opacity: .65; }
.ad-slot--leaderboard { min-height: 90px; }
.ad-slot--incontent { min-height: 120px; }
.ad-slot--infeed { min-height: 90px; grid-column: 1 / -1; }

/* --- Results --- */
.results-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: .75rem; margin: 2rem 0 1rem; }
.results-head h2 { font-size: 1.3rem; }
.results-actions { display: flex; align-items: center; gap: .6rem; }
.results-list { display: flex; flex-direction: column; gap: .8rem; }
.results-state { padding: 2rem 1rem; text-align: center; color: var(--text-muted); }
.results-state.is-hidden { display: none; }

.flight-card {
  display: grid; grid-template-columns: auto 1fr auto; gap: 1rem; align-items: center;
  padding: 1rem 1.1rem; position: relative;
}
.flight-card.is-cheapest { border-color: var(--cheap); box-shadow: 0 0 0 2px color-mix(in srgb, var(--cheap) 25%, transparent); }
.flight-airline { display: flex; flex-direction: column; align-items: center; gap: .3rem; width: 64px; text-align: center; }
.airline-avatar {
  width: 40px; height: 40px; border-radius: 50%; background: var(--primary-tint); color: var(--primary);
  display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: .8rem;
}
.flight-airline small { font-size: .68rem; color: var(--text-muted); }
.flight-info .route-line { display: flex; align-items: center; gap: .5rem; font-weight: 700; }
.flight-info .route-line .dots { flex: 1; height: 1px; background: repeating-linear-gradient(to right, var(--border) 0 4px, transparent 4px 8px); position: relative; }
.flight-info .route-line .dots svg { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); width: 14px; height: 14px; color: var(--text-muted); }
.flight-info .meta-line { display: flex; flex-wrap: wrap; gap: .5rem .9rem; margin-top: .35rem; font-size: .82rem; color: var(--text-muted); }
.flight-price { text-align: right; display: flex; flex-direction: column; align-items: flex-end; gap: .4rem; }
.flight-price .amount { font-family: var(--font-display); font-weight: 800; font-size: 1.35rem; color: var(--primary); }
[data-theme-dark] .flight-price .amount {}

/* --- Flexible dates / heatmap --- */
.heatmap-tool { padding: 1.4rem; }
.heatmap-controls { display: grid; grid-template-columns: 1fr 1fr 1fr auto; gap: .8rem; align-items: end; }
.heatmap-month-nav { display: flex; align-items: center; justify-content: space-between; margin: 1.4rem 0 .9rem; }
.heatmap-month-nav h3 { text-transform: capitalize; }
.heatmap-month-nav .btn-secondary { padding: .5rem .7rem; }
.heatmap-legend { display: flex; align-items: center; gap: .5rem; font-size: .78rem; color: var(--text-muted); margin-bottom: .8rem; }
.heatmap-legend .bar { height: 8px; width: 140px; border-radius: 999px; background: linear-gradient(to right, var(--cheap), var(--mid), var(--expensive)); }
.heatmap-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: .4rem; }
.heatmap-dow { text-align: center; font-size: .72rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; }
.heatmap-day {
  aspect-ratio: 1; border-radius: var(--radius-sm); display: flex; flex-direction: column;
  align-items: center; justify-content: center; gap: .1rem; font-size: .72rem; font-weight: 700;
  color: #0b1220; transition: transform .15s var(--ease-out);
  border: 1px solid rgba(0,0,0,.06);
}
.heatmap-day:not(.is-empty):hover { transform: scale(1.06); z-index: 1; box-shadow: var(--shadow); }
.heatmap-day.is-empty { visibility: hidden; }
.heatmap-day .d { font-size: .9rem; }
.heatmap-day .p { font-size: .66rem; opacity: .85; }

/* --- Deals / chollos --- */
.deals-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 1rem; }
.deal-card { padding: 1.1rem; display: flex; flex-direction: column; gap: .6rem; }
.deal-cover {
  height: 84px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center;
  font-family: var(--font-display); font-weight: 800; color: #fff; font-size: 1rem; letter-spacing: .02em;
}
.deal-route { font-weight: 700; }
.deal-meta { display: flex; justify-content: space-between; align-items: center; font-size: .82rem; color: var(--text-muted); }
.deal-price { font-family: var(--font-display); font-weight: 800; font-size: 1.2rem; color: var(--primary); }

/* --- Price alert --- */
.alert-card { padding: 1.5rem; display: grid; grid-template-columns: 1.1fr 1fr; gap: 2rem; align-items: center; }
.alert-form { display: grid; grid-template-columns: 1fr 1fr; gap: .8rem; }
.alert-form .field-email { grid-column: 1 / -1; }
.alert-form .btn { grid-column: 1 / -1; }
.alert-confirm { display: none; align-items: center; gap: .6rem; padding: .8rem 1rem; border-radius: var(--radius-sm); background: color-mix(in srgb, var(--cheap) 14%, transparent); color: var(--cheap); font-weight: 700; margin-top: .8rem; }
.alert-confirm.is-visible { display: flex; }

/* --- Blog --- */
.blog-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 1.1rem; }
.blog-card { padding: 1.2rem; display: flex; flex-direction: column; gap: .5rem; transition: transform .18s var(--ease-out), box-shadow .18s var(--ease-out); }
.blog-card:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
.blog-card .blog-meta { font-size: .75rem; color: var(--text-muted); text-transform: uppercase; letter-spacing: .04em; }
.blog-card h3 { font-size: 1.05rem; }
.blog-card p { color: var(--text-muted); font-size: .9rem; }
.blog-article { max-width: 720px; margin-inline: auto; padding-block: 2.5rem; }
.blog-article h1 { font-size: clamp(1.7rem, 4vw, 2.4rem); }
.blog-article .blog-meta { color: var(--text-muted); margin: .6rem 0 1.8rem; font-size: .9rem; }
.blog-article h2 { font-size: 1.3rem; margin: 1.8rem 0 .7rem; }
.blog-article p, .blog-article li { color: var(--text); margin-bottom: .9rem; }
.blog-article ul, .blog-article ol { padding-left: 1.4rem; list-style: disc; }
.blog-article ol { list-style: decimal; }

/* --- Share --- */
.share-row { display: flex; align-items: center; gap: .6rem; flex-wrap: wrap; }
.share-row .copied-tag { font-size: .82rem; color: var(--cheap); font-weight: 700; opacity: 0; transition: opacity .2s; }
.share-row .copied-tag.is-visible { opacity: 1; }

/* --- More tools cross-links --- */
.tools-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; }
.tool-link-card { padding: 1.2rem; display: flex; gap: .8rem; align-items: flex-start; transition: transform .18s var(--ease-out); }
.tool-link-card:hover { transform: translateY(-2px); }
.tool-link-card svg { width: 26px; height: 26px; color: var(--accent); flex-shrink: 0; }

/* --- Footer --- */
.site-footer { border-top: 1px solid var(--border); padding-block: 2.5rem 1.5rem; margin-top: 2rem; }
.footer-grid { display: grid; grid-template-columns: 1.4fr repeat(3, 1fr); gap: 1.6rem; }
.footer-col h4 { font-size: .82rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-muted); margin-bottom: .7rem; }
.footer-col a, .footer-col p { display: block; color: var(--text-muted); font-size: .88rem; margin-bottom: .5rem; }
.footer-col a:hover { color: var(--primary); }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: .6rem; margin-top: 2rem; padding-top: 1.2rem; border-top: 1px solid var(--border); font-size: .8rem; color: var(--text-muted); }

/* --- Popup ad (reservar) --- */
.ad-dialog { border: 0; border-radius: var(--radius-lg); padding: 0; max-width: 380px; width: calc(100% - 2rem); box-shadow: var(--shadow-lg); background: var(--surface); color: var(--text); }
.ad-dialog::backdrop { background: rgba(6, 12, 26, .55); backdrop-filter: blur(2px); }
.ad-dialog-inner { padding: 1.3rem; text-align: center; }
.ad-dialog-close { position: absolute; top: .6rem; right: .6rem; width: 32px; height: 32px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; background: var(--surface-2); }
.ad-dialog-inner .ad-slot { min-height: 200px; margin: .8rem 0 1rem; }
.ad-dialog-inner h3 { margin-bottom: .3rem; }

/* --- Corner toast ad --- */
.corner-ad {
  position: fixed; right: 1rem; bottom: 1rem; z-index: 60; width: 260px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-lg); padding: .8rem; display: none; align-items: flex-start; gap: .6rem;
  transform: translateY(12px); opacity: 0; transition: transform .3s var(--ease-out), opacity .3s var(--ease-out);
}
.corner-ad.is-visible { display: flex; transform: translateY(0); opacity: 1; }
.corner-ad .ad-slot { flex: 1; min-height: 60px; margin: 0; font-size: .68rem; }
.corner-ad-close { flex-shrink: 0; width: 22px; height: 22px; border-radius: 50%; background: var(--surface-2); display: inline-flex; align-items: center; justify-content: center; }

/* --- Demo mode badge --- */
.demo-note { display: flex; align-items: center; gap: .5rem; font-size: .78rem; color: var(--text-muted); margin-top: .9rem; }

/* =============================================================
   7. Effects
   ============================================================= */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity .5s var(--ease-out), transform .5s var(--ease-out); }
.reveal.is-visible { opacity: 1; transform: none; }

/* =============================================================
   8. Responsive
   ============================================================= */
@media (min-width: 540px) {
  .heatmap-controls { grid-template-columns: 1fr 1fr 1fr auto; }
}
@media (min-width: 720px) {
  .main-nav { display: flex; }
  .nav-toggle { display: none; }
  .mobile-nav { display: none !important; }
  .alert-card { grid-template-columns: 1.1fr 1fr; }
}
@media (max-width: 719px) {
  .search-form { grid-template-columns: 1fr; }
  .origin-destination { grid-template-columns: 1fr auto 1fr; }
  .search-form .field-dates { grid-template-columns: 1fr 1fr; }
  .alert-card { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .heatmap-controls { grid-template-columns: 1fr 1fr; }
  .heatmap-controls .btn { grid-column: 1 / -1; }
  .flight-card { grid-template-columns: 1fr; text-align: left; }
  .flight-airline { flex-direction: row; width: auto; justify-content: flex-start; }
  .flight-price { align-items: flex-start; flex-direction: row; justify-content: space-between; }
}
@media (min-width: 960px) {
  .footer-grid { grid-template-columns: 1.4fr repeat(3, 1fr); }
}

/* =============================================================
   9. Reduced-motion (only intrusive effects)
   ============================================================= */
@media (prefers-reduced-motion: reduce) {
  .corner-ad { transition: none; }
  .swap-btn:hover { transform: none; }
}