/* Walkaround. Readable on a phone in a hangar, readable on a desk.
   The visual language is technical drawing: a faint blueprint grid under the
   page, and a dusk sky band with an aircraft planform over the masthead. */

:root {
  --bg: #eef1f6;
  --bg-2: #e3e8f0;
  --surface: #ffffff;
  --surface-2: #eef1f5;
  --text: #14171d;
  --text-soft: #4f5866;
  --line: #d3dae4;
  --accent: #15507a;
  --accent-soft: #e2eef7;
  --plain: #0f6b4f;
  --plain-soft: #e3f3ec;
  --line-cal: #8a4b12;
  --line-cal-soft: #fbeedd;
  --grid: rgba(21, 80, 122, 0.07);
  --grid-strong: rgba(21, 80, 122, 0.11);
  --shadow: 0 1px 2px rgba(16, 32, 52, 0.05), 0 8px 24px rgba(16, 32, 52, 0.06);
  --shadow-lift: 0 2px 4px rgba(16, 32, 52, 0.07), 0 16px 40px rgba(16, 32, 52, 0.11);
  --radius: 12px;
  --wrap: 46rem;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0c1014;
    --bg-2: #0f141a;
    --surface: #161c23;
    --surface-2: #1d242d;
    --text: #e7eaf0;
    --text-soft: #97a2b1;
    --line: #29313b;
    --accent: #77b8e4;
    --accent-soft: #14283a;
    --plain: #63c8a3;
    --plain-soft: #10291f;
    --line-cal: #e0a86a;
    --line-cal-soft: #2e2113;
    --grid: rgba(119, 184, 228, 0.06);
    --grid-strong: rgba(119, 184, 228, 0.1);
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.36);
    --shadow-lift: 0 2px 4px rgba(0, 0, 0, 0.45), 0 16px 40px rgba(0, 0, 0, 0.5);
  }
}

:root[data-theme="dark"] {
  --bg: #0c1014;
  --bg-2: #0f141a;
  --surface: #161c23;
  --surface-2: #1d242d;
  --text: #e7eaf0;
  --text-soft: #97a2b1;
  --line: #29313b;
  --accent: #77b8e4;
  --accent-soft: #14283a;
  --plain: #63c8a3;
  --plain-soft: #10291f;
  --line-cal: #e0a86a;
  --line-cal-soft: #2e2113;
  --grid: rgba(119, 184, 228, 0.06);
  --grid-strong: rgba(119, 184, 228, 0.1);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 24px rgba(0, 0, 0, 0.36);
  --shadow-lift: 0 2px 4px rgba(0, 0, 0, 0.45), 0 16px 40px rgba(0, 0, 0, 0.5);
}

* { box-sizing: border-box; }

html { overflow-x: hidden; }

body {
  margin: 0;
  color: var(--text);
  font: 17px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
  background-color: var(--bg);
  /* Blueprint grid, a heavier rule every fifth line, and two soft glows so the
     page does not read as a flat slab. */
  background-image:
    radial-gradient(900px 420px at 78% -8%, var(--accent-soft), transparent 70%),
    radial-gradient(700px 500px at 5% 12%, var(--bg-2), transparent 70%),
    linear-gradient(var(--grid-strong) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-strong) 1px, transparent 1px),
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size:
    100% 100%,
    100% 100%,
    160px 160px,
    160px 160px,
    32px 32px,
    32px 32px;
  background-attachment: fixed, fixed, fixed, fixed, fixed, fixed;
}

.wrap {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 16px;
}

.skip { position: absolute; left: -9999px; }
.skip:focus {
  left: 16px; top: 8px;
  background: var(--surface);
  padding: 8px 12px; z-index: 20; border-radius: 6px;
}

/* Header */

.site-header {
  /* Solid first so a browser without color-mix still paints a header. */
  background: var(--surface);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 10;
}
@supports not (backdrop-filter: blur(4px)) {
  .site-header { background: var(--surface); }
}
.site-header .wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 16px;
  padding-top: 11px;
  padding-bottom: 11px;
}
.brand {
  font-weight: 700;
  font-size: 1.02rem;
  letter-spacing: -0.015em;
  color: var(--text);
  text-decoration: none;
  margin-right: auto;
  display: inline-flex;
  align-items: center;
  gap: 7px;
}
.brand::before {
  content: "";
  width: 15px; height: 15px;
  background: var(--accent);
  -webkit-mask: var(--plane-mask) center / contain no-repeat;
  mask: var(--plane-mask) center / contain no-repeat;
  transform: rotate(45deg);
  flex: none;
}
.site-header nav { display: flex; flex-wrap: wrap; gap: 13px; }
.site-header nav a {
  color: var(--text-soft);
  text-decoration: none;
  font-size: 0.85rem;
}
.site-header nav a:hover { color: var(--accent); }

/* The aircraft planform, reused as a mask and as hero art. */
:root {
  --plane-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 200 220'%3E%3Cg fill='%23000'%3E%3Cpath d='M100 10c4.4 15 5.6 33 5.6 50v86c0 15-2 26-5.6 34-3.6-8-5.6-19-5.6-34V60c0-17 1.2-35 5.6-50z'/%3E%3Cpath d='M95 74 22 140v11l73-39z'/%3E%3Cpath d='M105 74l73 66v11l-73-39z'/%3E%3Cpath d='M96.5 166 62 190v7l34.5-15z'/%3E%3Cpath d='M103.5 166 138 190v7l-34.5-15z'/%3E%3C/g%3E%3C/svg%3E");
}

/* Hero: a full bleed dusk sky with an aircraft planform and range rings. */

.hero {
  position: relative;
  margin: 0 calc(50% - 50vw) 34px;
  width: 100vw;
  max-width: 100vw;
  padding: 62px 0 56px;
  overflow: hidden;
  isolation: isolate;
  background:
    radial-gradient(120% 90% at 76% 108%, #c8703a 0%, rgba(200, 112, 58, 0) 46%),
    radial-gradient(90% 70% at 14% 0%, #2a5d8f 0%, rgba(42, 93, 143, 0) 62%),
    linear-gradient(170deg, #0a1522 0%, #12243a 44%, #1b3350 76%, #23405f 100%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.09);
}

/* Range rings and the aircraft itself. */
.hero-art {
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    repeating-radial-gradient(circle at 78% 112%,
      rgba(255, 255, 255, 0.07) 0 1px, rgba(255, 255, 255, 0) 1px 76px),
    var(--plane-mask);
  background-repeat: no-repeat, no-repeat;
  background-position: center, 86% 42%;
  background-size: 100% 100%, auto 168%;
  /* The asset is drawn black, so invert paints it white against the sky. A
     plain opacity is used rather than a blend mode, because blend results vary
     across browsers and this needs to be reliably visible but never loud. */
  filter: brightness(0) invert(1);
  opacity: 0.14;
}

.hero-inner {
  position: relative;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 16px;
}
.eyebrow {
  margin: 0 0 12px;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.62);
}
.hero h1 {
  margin: 0 0 12px;
  font-size: clamp(2.3rem, 8vw, 3.4rem);
  line-height: 1.02;
  letter-spacing: -0.035em;
  color: #fff;
  text-shadow: 0 2px 30px rgba(0, 0, 0, 0.35);
}
.hero .tagline {
  margin: 0 0 12px;
  font-size: 1.18rem;
  font-weight: 600;
  letter-spacing: -0.005em;
  color: rgba(255, 255, 255, 0.9);
}
.hero .standfirst {
  margin: 0;
  max-width: 32rem;
  font-size: 0.97rem;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.68);
}

/* Section heads */

.section-head { margin: 0 0 18px; }
.section-head h2 {
  margin: 0 0 6px;
  font-size: 1.55rem;
  letter-spacing: -0.025em;
  display: flex;
  align-items: center;
  gap: 11px;
}
.section-head h2::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--line), transparent);
}
.section-note {
  margin: 0;
  color: var(--text-soft);
  font-size: 0.93rem;
  max-width: 38rem;
}
.stats {
  margin: 8px 0 0;
  font-size: 0.8rem;
  color: var(--text-soft);
}

/* Today in aviation */

.today { margin: 0 0 52px; scroll-margin-top: 70px; }

.today-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 21rem), 1fr));
}

/* A headline is a card on the front page. The full story is its own page, so
   the front page stays scannable instead of becoming a wall of text. */
.story-card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 20px 16px;
  box-shadow: var(--shadow);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  transition: border-color 0.16s ease, transform 0.16s ease, box-shadow 0.16s ease;
}
.story-card::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: linear-gradient(var(--accent), transparent);
}
.story-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lift);
}
.story-card:hover .more { gap: 9px; }
.story-card .summary {
  margin: 0 0 14px;
  font-size: 0.94rem;
  color: var(--text-soft);
  flex: 1;
}
.story-meta {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  margin: 0;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}
.more {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent);
  transition: gap 0.16s ease;
}
.more::after { content: "\2192"; }

/* The story's own page */
.story-page > .summary {
  margin: 0 0 14px;
  font-size: 1.08rem;
  color: var(--text-soft);
}
.story-page > .kicker { margin-bottom: 8px; }
.story-page > .meta { margin-bottom: 22px; }
.kicker {
  margin: 0 0 7px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}
.kicker-text {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent);
}
.flag {
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--line-cal);
  background: var(--line-cal-soft);
  border: 1px solid var(--line-cal-soft);
  border-color: color-mix(in srgb, var(--line-cal) 30%, transparent);
  border-radius: 100px;
  padding: 2px 9px;
}
.story-card h3 {
  margin: 0 0 9px;
  font-size: 1.22rem;
  line-height: 1.25;
  letter-spacing: -0.018em;
}

/* Fleet brief */

.fleet { scroll-margin-top: 70px; }

.maker { padding-top: 32px; scroll-margin-top: 70px; }
.maker h2 {
  font-size: 1.22rem;
  letter-spacing: -0.015em;
  margin: 0 0 4px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--line);
}
.blurb {
  color: var(--text-soft);
  font-size: 0.9rem;
  margin: 10px 0 16px;
}

.grid {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 19rem), 1fr));
}

.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  text-decoration: none;
  color: inherit;
  box-shadow: var(--shadow);
  transition: border-color 0.16s ease, transform 0.16s ease, box-shadow 0.16s ease;
}
.card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lift);
}
.card h3 { margin: 0 0 2px; font-size: 1.08rem; letter-spacing: -0.012em; }
.card .variants { margin: 0 0 10px; font-size: 0.78rem; color: var(--text-soft); }
.card .glance { margin: 0 0 12px; font-size: 0.89rem; }

.meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
}
.pill {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 100px;
  padding: 2px 10px;
  font-size: 0.71rem;
  font-weight: 600;
}
.pill.quiet { background: var(--surface-2); color: var(--text-soft); }
.when { font-size: 0.74rem; color: var(--text-soft); }

/* Article */

.page {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 26px 34px;
  margin: 28px 0;
  box-shadow: var(--shadow);
}
.crumb { margin: 0 0 6px; font-size: 0.79rem; }
.crumb a { color: var(--text-soft); text-decoration: none; }
.crumb a:hover { color: var(--accent); }

.page h1 {
  font-size: clamp(1.75rem, 5vw, 2.25rem);
  line-height: 1.12;
  letter-spacing: -0.028em;
  margin: 0 0 4px;
}
.page > .variants { margin: 0 0 12px; color: var(--text-soft); font-size: 0.89rem; }
.page > .meta { margin-bottom: 22px; }

.prose h2 {
  font-size: 1.2rem;
  letter-spacing: -0.015em;
  margin: 34px 0 10px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  scroll-margin-top: 70px;
}
.prose h3 { font-size: 1.01rem; margin: 22px 0 6px; scroll-margin-top: 70px; }
.prose p { margin: 0 0 14px; }
.prose ul, .prose ol { margin: 0 0 16px; padding-left: 1.25rem; }
.prose li { margin-bottom: 7px; }

.prose a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
}
.prose a.gloss {
  color: inherit;
  text-decoration: underline dotted var(--text-soft);
  text-underline-offset: 3px;
  cursor: help;
}
.prose a.gloss:hover { color: var(--accent); text-decoration-color: var(--accent); }

.prose code {
  background: var(--surface-2);
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 0.875em;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}
.prose hr { border: 0; border-top: 1px solid var(--line); margin: 26px 0; }

/* Callouts */

blockquote {
  margin: 0 0 16px;
  padding: 13px 16px;
  border-left: 3px solid var(--line);
  background: var(--surface-2);
  border-radius: 0 8px 8px 0;
}
blockquote p { margin: 0; }
blockquote p + p { margin-top: 5px; }

.callout-label {
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.07em;
}
.callout-in-plain-terms { border-left-color: var(--plain); background: var(--plain-soft); }
.callout-in-plain-terms .callout-label { color: var(--plain); }
.callout-on-the-line { border-left-color: var(--line-cal); background: var(--line-cal-soft); }
.callout-on-the-line .callout-label { color: var(--line-cal); }

/* Tables */

.table-wrap {
  overflow-x: auto;
  margin: 0 0 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
}
table { border-collapse: collapse; width: 100%; font-size: 0.89rem; }
th, td {
  text-align: left;
  padding: 9px 12px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}
th {
  background: var(--surface-2);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-soft);
  white-space: nowrap;
}
tbody tr:last-child td { border-bottom: 0; }

/* Sources on an aircraft page read as reference, not prose */

#sources ~ ul { font-size: 0.83rem; color: var(--text-soft); }
#sources ~ ul a { word-break: break-word; }

/* Footer */

.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 48px;
  padding: 24px 0 40px;
  color: var(--text-soft);
  font-size: 0.83rem;
}
.site-footer p { margin: 0 0 8px; }
.fine { font-size: 0.77rem; opacity: 0.8; }

@media (max-width: 560px) {
  body { font-size: 16px; }
  .hero { padding: 44px 0 40px; margin-bottom: 28px; }
  .hero-art { background-size: 100% 100%, auto 118%; background-position: center, 94% 44%; opacity: 0.1; }
  .page {
    padding: 22px 16px 26px;
    border-radius: 0;
    margin-left: -16px;
    margin-right: -16px;
    border-left: 0;
    border-right: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}

@media print {
  .site-header, .site-footer, .skip, .hero-art { display: none; }
  body { background: #fff; }
  .page, .story-card { border: 0; box-shadow: none; padding: 0; }
  .story-sources[open] summary { display: none; }
}

/* Freshness. A card that changed in the current cycle is marked, so a reader
   coming back weekly can see what moved without reading everything again. */

.pill.fresh {
  background: var(--plain-soft);
  color: var(--plain);
  border: 1px solid var(--plain-soft);
  border-color: color-mix(in srgb, var(--plain) 32%, transparent);
}

.card.is-fresh,
.story-card.is-fresh {
  border-color: color-mix(in srgb, var(--plain) 38%, var(--line));
}
.card.is-fresh::after,
.story-card.is-fresh::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 0;
  height: 0;
  border-left: 30px solid transparent;
  border-top: 30px solid var(--plain);
  opacity: 0.85;
}
.card.is-fresh { position: relative; overflow: hidden; }

.story-card.is-fresh::before { background: linear-gradient(var(--plain), transparent); }

.story-card .story-meta .pill.fresh { margin-right: 8px; }

/* Aircraft silhouettes. Generated from real span and length figures by
   site/silhouettes.py, drawn in currentColor so they follow the theme. They
   are decorative, and marked aria-hidden, because the aircraft is always named
   in text right beside them. */

.silhouette {
  display: block;
  width: 100%;
  height: auto;
}

/* On a card: a banner strip above the title, on the blueprint grid. */
.card-art {
  display: block;
  margin: -16px -16px 14px;
  padding: 14px 18px 10px;
  background:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    var(--surface-2);
  background-size: 22px 22px, 22px 22px, 100% 100%;
  border-bottom: 1px solid var(--line);
}
.card-art .silhouette {
  max-height: 84px;
  color: var(--accent);
  opacity: 0.85;
  transition: transform 0.25s ease, opacity 0.25s ease;
}
.card:hover .card-art .silhouette {
  transform: translateX(4px);
  opacity: 1;
}
.card.is-fresh .card-art .silhouette { color: var(--plain); }

/* On the aircraft page: a wider, quieter banner. */
.page-art {
  margin: 4px 0 14px;
  padding: 16px 20px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    var(--surface-2);
  background-size: 26px 26px, 26px 26px, 100% 100%;
}
.page-art .silhouette {
  max-height: 128px;
  color: var(--accent);
  opacity: 0.9;
}

@media (max-width: 560px) {
  .card-art .silhouette { max-height: 68px; }
  .page-art { padding: 12px 14px; }
  .page-art .silhouette { max-height: 96px; }
}

@media print {
  .card-art, .page-art { background: none; border: 0; }
  .silhouette { color: #333; }
}

/* Kicker icons on the headline block */

.icon {
  width: 15px;
  height: 15px;
  flex: none;
  color: var(--accent);
}
.icon-large { width: 19px; height: 19px; }
.story-card.is-fresh .icon { color: var(--plain); }