/* ==========================================================================
   Altech Aviation — shared stylesheet
   Palette: cabin navy ground, brushed-brass accent, instrument-panel details
   Type:    Archivo (display) / IBM Plex Sans (body) / IBM Plex Mono (data)
   ========================================================================== */

:root {
  --ink:        #0A121B;   /* cabin at altitude, lights down */
  --ink-2:      #111E2B;
  --ink-3:      #1B2E3F;
  --hairline:   #2A3F52;
  --brass:      #C9A227;   /* cabin fittings, instrument backlight */
  --brass-soft: #E4C766;
  --paper:      #F6F7F8;
  --paper-2:    #ECEFF1;
  --fog:        #9FB1C0;   /* muted text on dark */
  --slate:      #4A5A69;   /* muted text on light */
  --white:      #FFFFFF;

  --measure: 68ch;
  --gutter: clamp(1.25rem, 4vw, 3.5rem);
  --shell: 1200px;

  --step--1: clamp(0.8rem, 0.77rem + 0.15vw, 0.875rem);
  --step-0:  clamp(1rem, 0.96rem + 0.2vw, 1.0625rem);
  --step-1:  clamp(1.15rem, 1.08rem + 0.35vw, 1.35rem);
  --step-2:  clamp(1.45rem, 1.3rem + 0.7vw, 1.9rem);
  --step-3:  clamp(1.85rem, 1.55rem + 1.4vw, 2.75rem);
  --step-4:  clamp(2.25rem, 1.75rem + 2.4vw, 3.85rem);
}

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "IBM Plex Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: var(--step-0);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }

a { color: inherit; }

h1, h2, h3, h4 {
  font-family: "Archivo", system-ui, sans-serif;
  font-variation-settings: "wdth" 112;
  line-height: 1.06;
  letter-spacing: -0.02em;
  margin: 0 0 0.5em;
  text-wrap: balance;
}

h1 { font-size: var(--step-4); font-weight: 700; }
h2 { font-size: var(--step-3); font-weight: 700; }
h3 { font-size: var(--step-2); font-weight: 600; letter-spacing: -0.015em; }
h4 { font-size: var(--step-1); font-weight: 600; letter-spacing: -0.01em; }

p { margin: 0 0 1.1em; max-width: var(--measure); }

/* --- Utility bits ------------------------------------------------------- */

.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.eyebrow {
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: var(--step--1);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--brass);
  margin: 0 0 1.1rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.eyebrow::before {
  content: "";
  width: 2rem;
  height: 1px;
  background: var(--brass);
  flex: none;
}

.section { padding-block: clamp(3.5rem, 8vw, 6.5rem); }
.section--dark { background: var(--ink); color: var(--paper); }
.section--dark h1, .section--dark h2, .section--dark h3 { color: var(--white); }
.section--dark p { color: var(--fog); }
.section--tint { background: var(--paper-2); }

.lede { font-size: var(--step-1); color: var(--slate); }
.section--dark .lede { color: var(--fog); }

.skip {
  position: absolute; left: -9999px;
  background: var(--brass); color: var(--ink);
  padding: 0.75rem 1.25rem; z-index: 100; font-weight: 600;
}
.skip:focus { left: 1rem; top: 1rem; }

:focus-visible {
  outline: 3px solid var(--brass);
  outline-offset: 3px;
}

/* --- Buttons ------------------------------------------------------------ */

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  font-weight: 500;
  text-decoration: none;
  padding: 0.95rem 1.6rem;
  border: 1px solid transparent;
  border-radius: 2px;
  cursor: pointer;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease, transform .18s ease;
}

.btn--primary,
a.btn--primary,
.section--dark .btn--primary { background: var(--brass); color: #000; }
.btn--primary:hover,
a.btn--primary:hover { background: var(--brass-soft); color: #000; transform: translateY(-1px); }

.btn--ghost { border-color: var(--hairline); color: var(--paper); }
.btn--ghost:hover { border-color: var(--brass); color: var(--brass); }

.btn--outline { border-color: rgba(10,18,27,.25); color: var(--ink); }
.btn--outline:hover { border-color: var(--ink); background: var(--ink); color: var(--paper); }

.btn-row { display: flex; flex-wrap: wrap; gap: 0.85rem; margin-top: 2rem; }

/* --- Masthead ----------------------------------------------------------- */

.masthead {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10,18,27,.94);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--hairline);
}

.masthead__inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1.5rem; min-height: 72px;
}

.masthead__brand {
  display: inline-flex; align-items: baseline; gap: 0.34em;
  text-decoration: none;
  font-family: "Archivo", system-ui, sans-serif;
  font-variation-settings: "wdth" 100;
  font-size: clamp(1.1rem, 1rem + 0.4vw, 1.35rem);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--white);
  line-height: 1;
  white-space: nowrap;
  transition: color .15s ease;
}
/* Both words share the wordmark's font, weight, size and colour — no
   second typeface, no brass second half. */
.masthead__brand b,
.masthead__brand i {
  font: inherit;
  font-style: normal;
  letter-spacing: inherit;
  color: var(--white);
}
.masthead__brand:hover,
.masthead__brand:hover b,
.masthead__brand:hover i { color: var(--brass-soft); }

.nav { display: flex; align-items: center; gap: clamp(1rem, 2.2vw, 2rem); }
.nav a {
  color: var(--fog); text-decoration: none;
  font-size: 0.95rem; padding: 0.35rem 0;
  border-bottom: 1px solid transparent;
  transition: color .15s ease, border-color .15s ease;
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--white); border-color: var(--brass); }
.nav .btn { padding: 0.7rem 1.15rem; border-bottom: 1px solid transparent; }

/* .nav a sets a muted colour and out-specifies .btn--primary, which made the
   header button light-on-brass. Restate it at matching specificity. */
.nav a.btn--primary,
.nav a.btn--primary:hover {
  color: #000;
  border-bottom-color: transparent;
}
.nav a.btn--ghost, .nav a.btn--outline { border-bottom-width: 1px; }

.nav-toggle {
  display: none; background: none; border: 1px solid var(--hairline);
  color: var(--paper); padding: 0.55rem 0.8rem; border-radius: 2px;
  font-family: "IBM Plex Mono", monospace; font-size: 0.75rem;
  letter-spacing: 0.1em; text-transform: uppercase; cursor: pointer;
}

@media (max-width: 860px) {
  .nav-toggle { display: block; }
  .nav {
    display: none; position: absolute; left: 0; right: 0; top: 100%;
    background: var(--ink); border-bottom: 1px solid var(--hairline);
    flex-direction: column; align-items: stretch; gap: 0;
    padding: 0.5rem var(--gutter) 1.5rem;
  }
  .nav[data-open="true"] { display: flex; }
  .nav a { padding: 0.85rem 0; border-bottom: 1px solid var(--hairline); }
  .nav .btn { margin-top: 1rem; justify-content: center; border-bottom: none; }
}

/* --- Hero --------------------------------------------------------------- */

.hero {
  background:
    radial-gradient(120% 90% at 78% 12%, rgba(201,162,39,.16), transparent 58%),
    radial-gradient(90% 70% at 8% 92%, rgba(74,155,209,.13), transparent 60%),
    var(--ink);
  color: var(--paper);
  padding-block: clamp(3.5rem, 9vw, 7rem);
  position: relative;
  overflow: hidden;
}

/* Faint great-circle arc — the moving map, abstracted */
.hero::after {
  content: "";
  position: absolute; inset: auto -10% -55% -10%;
  height: 70%;
  border-top: 1px solid rgba(201,162,39,.28);
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
  pointer-events: none;
}

.hero__grid {
  display: grid; gap: clamp(2.5rem, 5vw, 4rem);
  grid-template-columns: 1fr;
  align-items: center;
  position: relative; z-index: 1;
}

@media (min-width: 900px) {
  .hero__grid { grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr); }
}

.hero h1 { color: var(--white); }
.hero h1 em {
  font-style: normal;
  color: var(--brass);
}
.hero p { color: var(--fog); font-size: var(--step-1); max-width: 46ch; }

.hero__figure { position: relative; }
.hero__figure img { border-radius: 3px; }

/* --- Trust strip -------------------------------------------------------- */

.strip {
  background: var(--ink-2);
  border-top: 1px solid var(--hairline);
  border-bottom: 1px solid var(--hairline);
  padding-block: 1.4rem;
}
.strip__inner {
  display: flex; flex-wrap: wrap; align-items: center;
  gap: 0.75rem clamp(1rem, 3vw, 2.25rem);
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1);
  letter-spacing: 0.09em; text-transform: uppercase;
  color: var(--fog);
}
.strip__label { color: var(--brass); }

/* --- Generic grids ------------------------------------------------------ */

.grid { display: grid; gap: clamp(1.5rem, 3vw, 2.5rem); }
@media (min-width: 720px)  { .grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); } }
@media (min-width: 640px)  { .grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); } }

.split {
  display: grid; gap: clamp(2rem, 5vw, 4.5rem);
  align-items: center; grid-template-columns: 1fr;
}
@media (min-width: 900px) {
  .split { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .split--flip .split__media { order: -1; }
}

.card {
  background: var(--white);
  border: 1px solid rgba(10,18,27,.1);
  border-top: 2px solid var(--brass);
  border-radius: 2px;
  padding: clamp(1.5rem, 3vw, 2rem);
}
.card h3 { margin-bottom: 0.6rem; }
.card p { margin-bottom: 0; color: var(--slate); }

.section--dark .card {
  background: var(--ink-2);
  border-color: var(--hairline);
  border-top-color: var(--brass);
}
.section--dark .card p { color: var(--fog); }

/* --- Signature: the equipment data plate -------------------------------- */

.plate {
  background: linear-gradient(180deg, var(--ink-3), var(--ink-2));
  border: 1px solid var(--hairline);
  border-radius: 3px;
  box-shadow: inset 0 1px 0 rgba(255,255,255,.06);
  overflow: hidden;
}

.plate__head {
  display: flex; flex-wrap: wrap; gap: 0.5rem 1.5rem;
  justify-content: space-between; align-items: baseline;
  padding: 1rem 1.35rem;
  background: rgba(0,0,0,.28);
  border-bottom: 1px solid var(--hairline);
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1);
  letter-spacing: 0.13em; text-transform: uppercase;
  color: var(--brass);
}
.plate__head span:last-child { color: var(--fog); letter-spacing: 0.08em; }

.plate__body { list-style: none; margin: 0; padding: 0.5rem 1.35rem 1.35rem; }

.plate__row {
  display: flex; align-items: baseline; gap: 0.75rem;
  padding: 0.7rem 0;
  border-bottom: 1px dotted rgba(159,177,192,.3);
  font-family: "IBM Plex Mono", monospace;
  font-size: 0.9rem;
  color: var(--fog);
}
.plate__row:last-child { border-bottom: 0; }
.plate__row dt { flex: none; color: var(--fog); opacity: .75; min-width: 8.5rem; }
.plate__row dd { margin: 0; color: var(--white); }

/* Feature list with brass ticks */
.ticks { list-style: none; margin: 0; padding: 0; }
.ticks li {
  position: relative; padding-left: 1.9rem; margin-bottom: 0.85rem;
  max-width: var(--measure);
}
.ticks li::before {
  content: ""; position: absolute; left: 0; top: 0.55em;
  width: 0.45rem; height: 0.8rem;
  border-right: 2px solid var(--brass);
  border-bottom: 2px solid var(--brass);
  transform: rotate(42deg) translateY(-0.35em);
}

/* Chips — cabin system compatibility */
.chips { display: flex; flex-wrap: wrap; gap: 0.6rem; padding: 0; margin: 1.5rem 0 0; list-style: none; }
.chips li {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.07em;
  padding: 0.5rem 0.9rem;
  border: 1px solid var(--hairline);
  border-radius: 2px;
  color: var(--paper);
}
.section--tint .chips li, .section:not(.section--dark) .chips li {
  border-color: rgba(10,18,27,.2); color: var(--ink);
}

/* --- Gallery ------------------------------------------------------------ */

.gallery { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); }
.gallery figure { margin: 0; }
.gallery img {
  border: 1px solid var(--hairline); border-radius: 3px; width: 100%;
}
.gallery figcaption {
  font-family: "IBM Plex Mono", monospace;
  font-size: 0.78rem; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--fog); margin-top: 0.65rem;
}

/* --- Testimonials ------------------------------------------------------- */

.quote {
  border-left: 2px solid var(--brass);
  padding-left: clamp(1.25rem, 3vw, 2rem);
  margin: 0;
}
.quote p { font-size: var(--step-1); line-height: 1.5; letter-spacing: -0.01em; }
.quote footer {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--brass);
}
.quote footer span { display: block; color: var(--fog); letter-spacing: 0.05em; }

/* --- FAQ ---------------------------------------------------------------- */

.faq { border-top: 1px solid rgba(10,18,27,.14); max-width: 860px; }
.faq details { border-bottom: 1px solid rgba(10,18,27,.14); }
.faq summary {
  cursor: pointer; list-style: none;
  padding: 1.35rem 2.5rem 1.35rem 0;
  font-family: "Archivo", sans-serif;
  font-variation-settings: "wdth" 108;
  font-weight: 600; font-size: var(--step-1);
  letter-spacing: -0.012em; position: relative;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+"; position: absolute; right: 0.25rem; top: 1.15rem;
  font-family: "IBM Plex Mono", monospace; font-size: 1.4rem;
  color: var(--brass); transition: transform .2s ease;
}
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details > *:not(summary) { color: var(--slate); }
.faq details p:last-child { padding-bottom: 1.35rem; }

/* --- Forms -------------------------------------------------------------- */

.form { display: grid; gap: 1.15rem; max-width: 560px; }
.form label {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.09em;
  text-transform: uppercase; color: var(--slate);
  display: block; margin-bottom: 0.45rem;
}
.form input, .form select, .form textarea {
  width: 100%; font: inherit; color: var(--ink);
  background: var(--white);
  border: 1px solid rgba(10,18,27,.22);
  border-radius: 2px; padding: 0.8rem 0.9rem;
}
.form input:focus, .form select:focus, .form textarea:focus {
  border-color: var(--brass); outline: 2px solid rgba(201,162,39,.35); outline-offset: 0;
}
.form textarea { min-height: 150px; resize: vertical; }
.form .hp { position: absolute; left: -9999px; }

.contact-list { list-style: none; padding: 0; margin: 0; }
.contact-list li { margin-bottom: 1.35rem; }
.contact-list strong {
  display: block;
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.11em;
  text-transform: uppercase; color: var(--brass); font-weight: 500;
  margin-bottom: 0.2rem;
}
.contact-list a { color: inherit; }

/* --- Contact form status banner ----------------------------------------- */

.form-status {
  padding: 0.95rem 1.15rem;
  margin-bottom: 1.5rem;
  border-left: 3px solid var(--brass);
  background: var(--paper-2);
  color: var(--ink);
  font-size: var(--step-0);
  line-height: 1.5;
}
.form-status--ok  { border-left-color: #1E7A46; }
.form-status--bad { border-left-color: #B3261E; }
.form-status[hidden] { display: none; }

/* --- CTA band ----------------------------------------------------------- */

.band {
  background: var(--brass);
  color: var(--ink);
  padding-block: clamp(3rem, 6vw, 4.5rem);
}
.band h2 { color: var(--ink); margin-bottom: 0.4rem; }
.band p { color: rgba(10,18,27,.78); max-width: 52ch; }
.band .btn--primary { background: var(--ink); color: var(--brass); }
.band .btn--primary:hover { background: var(--ink-3); }

/* --- Footer ------------------------------------------------------------- */

.footer {
  background: var(--ink); color: var(--fog);
  padding-block: clamp(3rem, 6vw, 4.5rem) 2rem;
  border-top: 1px solid var(--hairline);
}
.footer h2 {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); font-weight: 500;
  letter-spacing: 0.13em; text-transform: uppercase;
  color: var(--brass); margin-bottom: 1.1rem;
}
.footer__grid {
  display: grid; gap: 2.5rem;
  grid-template-columns: 1fr;
}
/* Four columns once there is room; two on tablets so the Guides list
   does not squeeze into a single word per line. */
@media (min-width: 720px)  { .footer__grid { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1000px) { .footer__grid { grid-template-columns: 1.6fr 1fr 1fr 1fr; } }
.footer ul { list-style: none; margin: 0; padding: 0; }
.footer li { margin-bottom: 0.6rem; }
.footer a { color: var(--fog); text-decoration: none; }
.footer a:hover { color: var(--brass); }
.footer p { color: var(--fog); font-size: 0.95rem; }
.footer__legal {
  margin-top: 3rem; padding-top: 1.5rem;
  border-top: 1px solid var(--hairline);
  display: flex; flex-wrap: wrap; gap: 1rem; justify-content: space-between;
  font-family: "IBM Plex Mono", monospace;
  font-size: 0.78rem; letter-spacing: 0.07em; color: var(--fog);
}

.stores { display: flex; flex-wrap: wrap; gap: 0.85rem; margin-top: 1.75rem; }

/* --- Article pages ------------------------------------------------------ */

.article { max-width: 760px; }
.article h2 { margin-top: 2.75rem; }
.article h3 { margin-top: 2rem; }
.article ul, .article ol { max-width: var(--measure); padding-left: 1.2rem; }
.article li { margin-bottom: 0.55rem; }

.breadcrumb {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.09em;
  text-transform: uppercase; color: var(--slate);
  padding-block: 1.25rem 0;
}
.breadcrumb a { color: var(--slate); text-decoration: none; }
.breadcrumb a:hover { color: var(--ink); }

.table-wrap { overflow-x: auto; margin: 2rem 0; }
table { border-collapse: collapse; width: 100%; font-size: 0.95rem; }
th, td { text-align: left; padding: 0.85rem 1rem; border-bottom: 1px solid rgba(10,18,27,.14); vertical-align: top; }
th {
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.09em;
  text-transform: uppercase; color: var(--slate); font-weight: 500;
  border-bottom-color: rgba(10,18,27,.3);
}

/* --- Scroll reveal (progressive enhancement) ---------------------------- */

.reveal { opacity: 0; transform: translateY(14px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; } }

/* Screen-reader-only helper */
.visually-hidden {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}

/* --- Scan-to-watch steps ------------------------------------------------ */

.steps {
  list-style: none; margin: 2.5rem 0 0; padding: 0;
  display: grid; gap: clamp(1.5rem, 3vw, 2.25rem);
  counter-reset: step;
}
@media (min-width: 760px) { .steps { grid-template-columns: repeat(3, minmax(0, 1fr)); } }

.steps li {
  counter-increment: step;
  padding-top: 1.4rem;
  border-top: 1px solid var(--hairline);
  position: relative;
}
.steps li::before {
  content: "0" counter(step);
  display: block;
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1);
  letter-spacing: 0.14em;
  color: var(--brass);
  margin-bottom: 0.6rem;
}
.steps li::after {
  content: ""; position: absolute; top: -1px; left: 0;
  width: 2.5rem; height: 1px; background: var(--brass);
}
.steps h3 { font-size: var(--step-1); margin-bottom: 0.35rem; }
.steps p { margin: 0; font-size: 0.97rem; }

.section:not(.section--dark) .steps li { border-top-color: rgba(10,18,27,.16); }

/* Callout — the "new" flag.
   Written as p.flag so it beats `.section--dark p`, which sets a muted colour
   and would otherwise render this light-on-brass. */
p.flag, .flag {
  display: inline-flex; align-items: center; gap: 0.55rem;
  font-family: "IBM Plex Mono", monospace;
  font-size: var(--step--1); letter-spacing: 0.13em; text-transform: uppercase;
  color: var(--ink); background: var(--brass);
  padding: 0.35rem 0.7rem; border-radius: 2px;
  margin-bottom: 1.25rem;
}

.figure-wide { margin: 0; }
.figure-wide img { width: 100%; }
.figure-wide figcaption {
  font-family: "IBM Plex Mono", monospace;
  font-size: 0.78rem; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--fog); margin-top: 0.9rem; text-align: center;
}