/* ============================================================
   Exhaustless — Space-time-price
   Design system: editorial × engineering
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:opsz,wght,SOFT,WONK@9..144,300..900,0..100,0..1&family=Manrope:wght@300;400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* --- Tokens ------------------------------------------------- */
:root {
  /* Color */
  --ink:        #0e1a2b;
  --ink-2:      #2a3a4f;
  --paper:      #f5f2ea;
  --paper-2:    #ebe6da;
  --rule:       #c9c2b0;
  --accent:     #e85d2f;   /* FAA orange */
  --teal:       #2a5f6f;
  --muted:      #7a7568;
  --success:    #4a7c59;

  /* Typography */
  --f-display:  'Fraunces', Georgia, 'Times New Roman', serif;
  --f-body:     'Manrope', -apple-system, system-ui, sans-serif;
  --f-mono:     'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  /* Scale */
  --step--1:    clamp(0.83rem, 0.79rem + 0.20vw, 0.94rem);
  --step-0:     clamp(1.00rem, 0.94rem + 0.31vw, 1.13rem);
  --step-1:     clamp(1.20rem, 1.11rem + 0.46vw, 1.41rem);
  --step-2:     clamp(1.44rem, 1.31rem + 0.66vw, 1.76rem);
  --step-3:     clamp(1.73rem, 1.55rem + 0.92vw, 2.20rem);
  --step-4:     clamp(2.07rem, 1.83rem + 1.25vw, 2.75rem);
  --step-5:     clamp(2.49rem, 2.15rem + 1.70vw, 3.43rem);
  --step-6:     clamp(2.99rem, 2.53rem + 2.27vw, 4.29rem);

  /* Layout */
  --max-w:      78rem;
  --max-prose:  44rem;
  --gutter:     clamp(1.25rem, 1rem + 1.5vw, 2.5rem);
}

/* --- Reset -------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body, h1, h2, h3, h4, p, ul, ol, figure, blockquote { margin: 0; padding: 0; }
ul, ol { list-style: none; }
img, svg { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
button { background: none; border: 0; color: inherit; font: inherit; cursor: pointer; }
input, textarea, select { font: inherit; color: inherit; }

/* --- Base --------------------------------------------------- */
body {
  font-family: var(--f-body);
  font-size: var(--step-0);
  line-height: 1.55;
  color: var(--ink);
  background: var(--paper);
  background-image:
    radial-gradient(rgba(14,26,43,0.025) 1px, transparent 1px);
  background-size: 24px 24px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

::selection { background: var(--accent); color: var(--paper); }

/* --- Layout primitives ------------------------------------- */
.wrap {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

main { flex: 1; padding-block: clamp(3rem, 5vw, 5.5rem); }

/* --- Header / nav ------------------------------------------ */
.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--paper);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(140%) blur(8px);
  background: rgba(245,242,234,0.92);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 1rem;
  gap: 1.5rem;
}

.brand {
  font-family: var(--f-mono);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--ink);
}

.brand::before {
  content: "";
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  display: inline-block;
}

.brand small {
  font-weight: 400;
  color: var(--muted);
  letter-spacing: 0.12em;
}

.nav {
  display: flex;
  gap: clamp(1rem, 2vw, 2rem);
  align-items: center;
}

.nav a {
  font-family: var(--f-mono);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-2);
  position: relative;
  padding-block: 0.4rem;
  transition: color 0.18s ease;
}

.nav a:hover { color: var(--ink); }

.nav a.is-current {
  color: var(--ink);
}

.nav a.is-current::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -2px;
  height: 2px;
  background: var(--accent);
}

.nav-toggle {
  display: none;
  font-family: var(--f-mono);
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 0.4rem 0.6rem;
  border: 1px solid var(--rule);
}

@media (max-width: 720px) {
  .nav-toggle { display: inline-flex; align-items: center; gap: 0.5rem; }
  .nav {
    position: absolute;
    top: 100%; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--rule);
    padding: 0.5rem var(--gutter) 1rem;
    display: none;
  }
  .nav.is-open { display: flex; }
  .nav a {
    padding-block: 0.85rem;
    border-bottom: 1px solid var(--paper-2);
  }
  .nav a:last-child { border-bottom: 0; }
  .nav a.is-current::after { display: none; }
  .nav a.is-current { color: var(--accent); }
}

/* --- Section markers --------------------------------------- */
.section-marker {
  font-family: var(--f-mono);
  font-size: 0.74rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.section-marker::before {
  content: "";
  display: block;
  width: 2.5rem;
  height: 1px;
  background: var(--ink);
}

/* --- Typography -------------------------------------------- */
h1, h2, h3, h4 {
  font-family: var(--f-display);
  font-variation-settings: "opsz" 144, "SOFT" 0, "WONK" 0;
  color: var(--ink);
  line-height: 1.05;
  letter-spacing: -0.02em;
  font-weight: 400;
}

.h-display {
  font-size: var(--step-6);
  line-height: 0.98;
  letter-spacing: -0.035em;
  font-weight: 350;
}

.h-display em {
  font-style: italic;
  font-variation-settings: "opsz" 144, "SOFT" 100, "WONK" 1;
  color: var(--accent);
}

.h-1 { font-size: var(--step-5); }
.h-2 { font-size: var(--step-4); margin-bottom: 1rem; }
.h-3 { font-size: var(--step-2); margin-bottom: 0.5rem; }
.h-4 { font-size: var(--step-1); margin-bottom: 0.5rem; }

.lede {
  font-family: var(--f-display);
  font-size: var(--step-2);
  font-weight: 350;
  line-height: 1.3;
  color: var(--ink-2);
  letter-spacing: -0.01em;
  max-width: 38ch;
}

p { max-width: var(--max-prose); }
p + p { margin-top: 1rem; }

a.link {
  color: var(--teal);
  border-bottom: 1px solid currentColor;
  transition: color 0.18s ease;
}
a.link:hover { color: var(--accent); }

/* --- Hero --------------------------------------------------- */
.hero {
  padding-block: clamp(2rem, 5vw, 4rem) clamp(3rem, 6vw, 5rem);
  border-bottom: 1px solid var(--rule);
}

.hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(2rem, 4vw, 3rem);
}

@media (min-width: 880px) {
  .hero__grid { grid-template-columns: 1.5fr 1fr; align-items: end; }
}

.hero__meta {
  font-family: var(--f-mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  display: grid;
  gap: 0.5rem;
  border-left: 2px solid var(--accent);
  padding-left: 1rem;
}

.hero__meta strong {
  font-weight: 600;
  color: var(--ink);
}

/* --- Channels grid (home page) ---------------------------- */
.channels {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0;
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  margin-block: clamp(3rem, 5vw, 5rem);
}

.channel {
  padding: clamp(1.5rem, 3vw, 2.5rem);
  border-right: 1px solid var(--rule);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: background 0.18s ease;
  position: relative;
}

.channel:last-child { border-right: 0; }
.channel:hover { background: var(--paper-2); }

@media (max-width: 720px) {
  .channel { border-right: 0; border-bottom: 1px solid var(--rule); }
  .channel:last-child { border-bottom: 0; }
}

.channel__num {
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  color: var(--accent);
}

.channel__title {
  font-family: var(--f-display);
  font-size: var(--step-3);
  font-weight: 400;
  line-height: 1;
  letter-spacing: -0.02em;
}

.channel__body { color: var(--ink-2); font-size: var(--step--1); line-height: 1.55; }

.channel__status {
  font-family: var(--f-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px dashed var(--rule);
}

.channel__status .dot {
  display: inline-block;
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--success); margin-right: 0.5rem; vertical-align: 1px;
}
.channel__status.is-tbd .dot { background: var(--muted); }

/* --- Two-col content (highways, aviation) ----------------- */
.two-col {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(2rem, 4vw, 3.5rem);
  margin-top: clamp(2.5rem, 5vw, 4rem);
}
@media (min-width: 820px) {
  .two-col { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

.col-card {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.col-card__label {
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
}

.col-card h3 { font-size: var(--step-3); }

/* --- Benefits table --------------------------------------- */
.benefits {
  margin-top: clamp(2rem, 4vw, 3.5rem);
  border-top: 1px solid var(--ink);
}

.benefit-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.25rem;
  padding-block: 1.25rem;
  border-bottom: 1px solid var(--rule);
  align-items: baseline;
}

@media (min-width: 640px) {
  .benefit-row {
    grid-template-columns: 12rem minmax(0, 1fr);
    gap: 2rem;
  }
}

.benefit-row__label {
  font-family: var(--f-display);
  font-size: var(--step-2);
  font-weight: 400;
  letter-spacing: -0.02em;
  line-height: 1;
}

.benefit-row__body {
  color: var(--ink-2);
  max-width: 56ch;
}

/* --- Lists with bullets ----------------------------------- */
.bullet-list { display: grid; gap: 0.75rem; margin-top: 1rem; max-width: var(--max-prose); }
.bullet-list li {
  padding-left: 1.5rem;
  position: relative;
  color: var(--ink-2);
}
.bullet-list li::before {
  content: "";
  position: absolute;
  left: 0; top: 0.65em;
  width: 0.8rem; height: 1px;
  background: var(--accent);
}

/* --- Resource / citation list ----------------------------- */
.cite-list { display: grid; gap: 0.6rem; margin-top: 1rem; }
.cite-list li {
  padding-left: 1.5rem;
  position: relative;
  font-size: var(--step--1);
  color: var(--ink-2);
  line-height: 1.5;
}
.cite-list li::before {
  content: counter(citecount, decimal-leading-zero);
  counter-increment: citecount;
  position: absolute;
  left: 0; top: 0.05em;
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--muted);
}
.cite-list { counter-reset: citecount; }

.cite-list a { color: var(--teal); border-bottom: 1px solid transparent; transition: border-color 0.18s ease; }
.cite-list a:hover { border-color: currentColor; color: var(--accent); }

.cite-list .meta {
  font-family: var(--f-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--muted);
  text-transform: uppercase;
  margin-left: 0.5rem;
}

/* --- Stat block (cost of delays) -------------------------- */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 0;
  border: 1px solid var(--ink);
  margin-top: 1.5rem;
}

.stat {
  padding: 1.25rem 1.5rem;
  border-right: 1px solid var(--rule);
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}
.stat:last-child { border-right: 0; }

@media (max-width: 720px) {
  .stat { border-right: 0; border-bottom: 1px solid var(--rule); }
  .stat:last-child { border-bottom: 0; }
}

.stat__label {
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.stat__value {
  font-family: var(--f-display);
  font-size: var(--step-4);
  font-weight: 350;
  letter-spacing: -0.02em;
  line-height: 1;
  color: var(--ink);
}

.stat__value em {
  font-size: 0.6em;
  color: var(--muted);
  font-style: normal;
  font-family: var(--f-mono);
  letter-spacing: 0.05em;
}

/* --- Block section divider ------------------------------- */
.divider {
  border: 0;
  border-top: 1px solid var(--rule);
  margin-block: clamp(3rem, 5vw, 4.5rem);
}

/* --- Form ------------------------------------------------- */
.form {
  display: grid;
  gap: 1.25rem;
  max-width: 36rem;
  margin-top: 2rem;
}

.field {
  display: grid;
  gap: 0.45rem;
}

.field__label {
  font-family: var(--f-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}

.field__label .req { color: var(--accent); }

.field__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.75rem;
}
@media (min-width: 560px) {
  .field__row { grid-template-columns: 1fr 1fr; }
}

.input, .textarea {
  background: transparent;
  border: 0;
  border-bottom: 1px solid var(--rule);
  padding: 0.6rem 0;
  font-size: var(--step-0);
  color: var(--ink);
  font-family: var(--f-body);
  transition: border-color 0.18s ease;
  width: 100%;
}

.input:focus, .textarea:focus {
  outline: none;
  border-bottom-color: var(--accent);
}

.textarea {
  min-height: 7rem;
  resize: vertical;
  border: 1px solid var(--rule);
  padding: 0.75rem;
}

.input::placeholder, .textarea::placeholder {
  color: var(--muted);
  opacity: 0.7;
}

.honeypot {
  position: absolute;
  left: -9999px;
  width: 1px; height: 1px;
  overflow: hidden;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.85rem 1.5rem;
  font-family: var(--f-mono);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-weight: 600;
  background: var(--ink);
  color: var(--paper);
  border: 1px solid var(--ink);
  transition: background 0.18s ease, color 0.18s ease;
  justify-self: start;
}

.btn:hover { background: var(--accent); border-color: var(--accent); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn::after { content: "→"; transition: transform 0.18s ease; }
.btn:hover::after { transform: translateX(3px); }

.form-status {
  font-family: var(--f-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  padding: 0.75rem 1rem;
  border-left: 3px solid var(--rule);
  display: none;
}
.form-status.is-success { display: block; border-left-color: var(--success); color: var(--success); }
.form-status.is-error { display: block; border-left-color: var(--accent); color: var(--accent); }

/* --- Footer ----------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--rule);
  margin-top: clamp(3rem, 6vw, 6rem);
  padding-block: 2rem 3rem;
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 1.25rem;
}

.site-footer__copy {
  font-family: var(--f-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.site-footer__nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
}

.site-footer__nav a {
  font-family: var(--f-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-2);
  transition: color 0.18s ease;
}
.site-footer__nav a:hover { color: var(--accent); }

.site-footer__line {
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, var(--rule) 30%, var(--rule) 70%, transparent 100%);
  margin-bottom: 1.5rem;
}

/* --- Page intro ------------------------------------------- */
.page-intro {
  display: grid;
  gap: 1rem;
  margin-bottom: clamp(2rem, 4vw, 3rem);
  padding-bottom: clamp(2rem, 4vw, 3rem);
  border-bottom: 1px solid var(--rule);
}

/* --- Visually hidden -------------------------------------- */
.vh {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* --- Print ------------------------------------------------ */
@media print {
  body { background: #fff; }
  .site-header, .site-footer__nav { display: none; }
}