/* ============================================================
   FuelTrust — shared site design system (fueltrust.io)
   World: engine-room metering panel × full-bleed maritime photo.
   Tokens from ../branding/FUELTRUST-BRAND.md — do not improvise colors.
   Shared by index.html and future /product|/industry pages.
   ============================================================ */

:root {
  --navy: #0a387c;
  --navy-dark: #051e4a;
  --navy-deep: #041838;      /* scrim floor for photo bands */
  --navy-light: #4a6ba3;
  --teal: #278a92;
  --teal-light: #5babb5;
  --teal-dark: #1a5a63;
  --cyan: #0089c7;
  --orange: #ef9000;
  --orange-bright: #ffa41f;
  --yellow: #f9bd19;
  --ink: #12233d;            /* body text on light */
  --ink-2: #3d5578;          /* secondary text on light (navy-tinted, not gray) */
  --paper: #ffffff;
  --deck: #f2f5f8;           /* alternate light ground */
  --line: #d8e2ec;           /* hairlines on light */
  --snow: #eef4f9;           /* body text on dark */
  --snow-2: #b9cde2;         /* secondary text on dark */
  --maxw: 1160px;
  --radius: 3px;             /* instrument, not app */
  --font-display: 'Raleway', 'Helvetica Neue', Arial, sans-serif;
  --font-body: 'Roboto', -apple-system, 'Segoe UI', Arial, sans-serif;
  --font-meter: 'Roboto Mono', 'SF Mono', Menlo, monospace; /* measurement voice only */
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--teal-dark); text-decoration: none; } /* teal-dark: AA on white; brighter teals reserved for dark grounds */
a:hover { color: var(--navy); }

/* ---------- type scale ---------- */
h1, h2, h3 { font-family: var(--font-display); color: var(--navy); }
h1 {
  font-weight: 300;
  font-size: clamp(2.4rem, 6vw, 4.6rem);
  letter-spacing: .14em;
  line-height: 1.12;
  text-transform: uppercase;
  color: #fff;
  text-wrap: balance;
}
h1 strong { font-weight: 700; }
h2 { font-weight: 700; font-size: clamp(1.5rem, 3vw, 2.1rem); letter-spacing: .02em; line-height: 1.25; text-wrap: balance; }
h3 { font-weight: 600; font-size: 1.12rem; letter-spacing: .01em; }
.lede { font-size: 1.16rem; color: var(--ink-2); max-width: 62ch; }
p { max-width: 70ch; }

/* ---------- legend plate: the section-heading grammar ---------- */
.plate {
  display: inline-block;
  border: 1px solid var(--teal);
  padding: 10px 26px;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: .84rem;
  letter-spacing: .28em;
  text-transform: uppercase;
  color: var(--navy);
  background: var(--paper);
  position: relative;
}
.plate::before, .plate::after {  /* panel screws */
  content: '';
  position: absolute; top: 50%; transform: translateY(-50%);
  width: 5px; height: 5px; border-radius: 50%;
  background: var(--teal-light);
}
.plate::before { left: 9px; }
.plate::after { right: 9px; }
.plate--dark { background: transparent; color: var(--snow); border-color: var(--teal-light); }
.section-head { text-align: center; margin-bottom: 26px; }
.section-head h2 { margin-top: 22px; }
.section-head .lede { margin: 14px auto 0; }

/* ---------- layout ---------- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 28px; }
section { padding: 104px 0; }
section.tight { padding: 72px 0; }
.ground-deck { background: var(--deck); }

/* ---------- nav ---------- */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  transition: background .25s ease-out, box-shadow .25s ease-out;
  padding: 18px 0;
}
.nav.solid { background: var(--navy-deep); box-shadow: 0 2px 14px rgba(4, 24, 56, .45); padding: 10px 0; }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.nav-brand { display: flex; align-items: center; gap: 12px; }
.nav-brand img { height: 40px; width: auto; }
.nav-brand span {
  font-family: var(--font-display); font-weight: 700; font-size: 1.28rem;
  color: #fff; letter-spacing: .04em;
}
.nav-links { display: flex; align-items: center; gap: 30px; list-style: none; }
.nav-links a {
  font-family: var(--font-display); font-weight: 600; font-size: .8rem;
  letter-spacing: .16em; text-transform: uppercase; color: var(--snow);
}
.nav-links a:hover { color: var(--teal-light); }
.btn-nav { border: 1px solid var(--orange); color: var(--orange-bright) !important; padding: 9px 18px; border-radius: var(--radius); }
.btn-nav:hover { background: var(--orange); color: #fff !important; }
.nav-toggle { display: none; background: none; border: 1px solid var(--snow-2); border-radius: var(--radius); color: var(--snow); font-size: 1.2rem; padding: 4px 12px; cursor: pointer; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block; font-family: var(--font-display); font-weight: 700;
  font-size: .82rem; letter-spacing: .2em; text-transform: uppercase;
  padding: 15px 34px; border-radius: var(--radius); cursor: pointer;
  transition: transform .15s ease-out, background .15s ease-out, color .15s ease-out;
  border: 1px solid transparent;
}
.btn-primary { background: var(--orange); color: #fff; }
.btn-primary:hover { background: var(--orange-bright); color: #fff; transform: translateY(-1px); }
.btn-ghost { border-color: rgba(255,255,255,.75); color: #fff; }
.btn-ghost:hover { background: rgba(255,255,255,.12); color: #fff; transform: translateY(-1px); }
.btn-ghost-navy { border-color: var(--navy); color: var(--navy); }
.btn-ghost-navy:hover { background: var(--navy); color: #fff; transform: translateY(-1px); }
.btn:focus-visible, a:focus-visible, button:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; }

/* ---------- image holders ----------
   Every photographic slot. Real photography replaces the SVG file
   (see IMAGE-MANIFEST.md); the HOLDER tag is removed by deleting
   the data-holder attribute — no CSS surgery needed. */
.img-slot { position: relative; overflow: hidden; background: var(--navy-dark); }
.img-slot > img, .img-slot > .slot-bg { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.img-slot[data-holder]::after {
  content: 'IMAGE HOLDER · ' attr(data-holder);
  position: absolute; right: 10px; bottom: 8px; z-index: 5;
  font-family: var(--font-meter); font-size: .58rem; letter-spacing: .1em;
  color: rgba(255,255,255,.85); background: rgba(4,24,56,.55);
  padding: 3px 8px; border: 1px dashed rgba(255,255,255,.45); border-radius: 2px;
  pointer-events: none;
}

/* ---------- hero ---------- */
.hero {
  position: relative; min-height: 100svh; display: flex; flex-direction: column;
  justify-content: center; align-items: center; text-align: center;
  padding: 140px 24px 120px; color: #fff;
}
.hero .scrim {  /* navy scrim over photography — never flat black */
  position: absolute; inset: 0; z-index: 1;
  background: linear-gradient(180deg, rgba(4,24,56,.62) 0%, rgba(4,24,56,.28) 42%, rgba(4,24,56,.78) 100%);
}
.hero-inner { position: relative; z-index: 2; max-width: 1000px; }
.hero-kicker {
  font-family: var(--font-display); font-weight: 600; font-size: .86rem;
  letter-spacing: .42em; text-transform: uppercase; color: var(--teal-light);
  margin-bottom: 26px;
}
.hero-sub { margin: 30px auto 40px; max-width: 58ch; font-size: 1.12rem; color: var(--snow); }
.hero-sub .tagline { font-family: var(--font-display); font-weight: 600; color: var(--teal-light); white-space: nowrap; }
.hero-ctas { display: flex; gap: 18px; justify-content: center; flex-wrap: wrap; }
.hero-scroll {
  position: absolute; bottom: 110px; left: 50%; transform: translateX(-50%); z-index: 2;
  color: rgba(255,255,255,.8); font-size: 1.4rem; line-height: 1;
}

/* hero instrument strip — product truth, not fake telemetry */
.meter-strip {
  position: absolute; bottom: 0; left: 0; right: 0; z-index: 3;
  background: rgba(4,24,56,.82); border-top: 1px solid rgba(91,171,181,.4);
}
.meter-strip .wrap { display: flex; justify-content: center; gap: 0; }
.meter-cell {
  flex: 1; max-width: 340px; padding: 18px 26px; text-align: center;
  border-left: 1px solid rgba(91,171,181,.25);
}
.meter-cell:first-child { border-left: none; }
.meter-cell .meter-val {
  font-family: var(--font-meter); font-size: 1.24rem; font-weight: 500;
  color: var(--teal-light); font-variant-numeric: tabular-nums;
}
.meter-cell .meter-lbl {
  font-family: var(--font-display); font-weight: 600; font-size: .64rem;
  letter-spacing: .22em; text-transform: uppercase; color: var(--snow-2); margin-top: 4px;
}

/* ---------- mimic diagram (earth → emissions) ---------- */
.mimic { margin: 54px auto 0; max-width: 980px; }
.mimic svg { width: 100%; height: auto; display: block; }
.mimic .flow-path { stroke-dasharray: 2600; stroke-dashoffset: 2600; }
.mimic.lit .flow-path { animation: flowdraw 2.6s ease-out forwards; }
.mimic .node-lamp { opacity: 0; }
.mimic.lit .node-lamp { animation: lampon .5s ease-out forwards; }
.mimic.lit .node-lamp:nth-of-type(1) { animation-delay: .5s; }
@keyframes flowdraw { to { stroke-dashoffset: 0; } }
@keyframes lampon { to { opacity: 1; } }
.mimic-caption {
  text-align: center; font-family: var(--font-meter); font-size: .68rem;
  letter-spacing: .14em; color: var(--ink-2); margin-top: 14px; text-transform: uppercase;
}

/* ---------- hex tiles (honeycomb, pointy-top) ---------- */
.hex-field { margin-top: 64px; }
.hex-row { display: flex; justify-content: center; gap: 22px; }
.hex-row + .hex-row { margin-top: -62px; }
.hex {
  --hw: 284px;
  width: var(--hw); height: calc(var(--hw) * 1.14);
  clip-path: polygon(50% 0, 100% 25%, 100% 75%, 50% 100%, 0 75%, 0 25%);
  position: relative; display: flex; flex-direction: column;
  justify-content: center; align-items: center; text-align: center;
  color: #fff; padding: 30px;
}
.hex .scrim {
  position: absolute; inset: 0; z-index: 1;
  background: linear-gradient(180deg, rgba(5,30,74,.45), rgba(4,24,56,.72));
  transition: background .2s ease-out;
}
.hex:hover .scrim { background: linear-gradient(180deg, rgba(5,30,74,.3), rgba(4,24,56,.6)); }
.hex-body { position: relative; z-index: 2; display: flex; flex-direction: column; align-items: center; gap: 12px; }
.hex-body img { height: 30px; width: auto; }   /* product wordmark PNGs */
.hex-name { font-family: var(--font-display); font-weight: 700; font-size: 1.02rem; letter-spacing: .1em; text-transform: uppercase; }
.hex-role { font-size: .8rem; color: var(--snow-2); max-width: 24ch; line-height: 1.45; }
.hex-cta {
  font-family: var(--font-display); font-weight: 700; font-size: .66rem;
  letter-spacing: .22em; text-transform: uppercase; color: #fff;
  border: 1px solid rgba(255,255,255,.8); padding: 8px 16px; border-radius: 2px;
  transition: background .15s ease-out;
}
.hex:hover .hex-cta { background: var(--orange); border-color: var(--orange); }

/* ---------- product rows (dual-track detail) ---------- */
.track-label {
  font-family: var(--font-meter); font-size: .7rem; letter-spacing: .2em;
  text-transform: uppercase; color: var(--teal-dark); margin-bottom: 8px;
}
.prod-row {
  display: grid; grid-template-columns: 300px 1fr; gap: 44px;
  padding: 40px 0; border-top: 1px solid var(--line); align-items: start;
}
.prod-row:last-child { border-bottom: 1px solid var(--line); }
.prod-id img { height: 34px; width: auto; margin-bottom: 12px; }
.prod-id .prod-tm { font-family: var(--font-display); font-weight: 700; font-size: 1.2rem; color: var(--navy); }
.prod-id .prod-kind { font-family: var(--font-meter); font-size: .68rem; letter-spacing: .16em; text-transform: uppercase; color: var(--ink-2); margin-top: 6px; }
.prod-copy p { color: var(--ink-2); }
.prod-copy ul { margin: 14px 0 18px 0; padding-left: 0; list-style: none; }
.prod-copy li { padding-left: 26px; position: relative; margin-bottom: 8px; color: var(--ink); }
.prod-copy li::before {   /* indicator lamp */
  content: ''; position: absolute; left: 4px; top: .52em;
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--teal); box-shadow: 0 0 0 2px rgba(39,138,146,.22);
}
.prod-link { font-family: var(--font-display); font-weight: 700; font-size: .76rem; letter-spacing: .18em; text-transform: uppercase; }

/* ---------- dark measurement band ---------- */
.band-dark { position: relative; color: var(--snow); overflow: hidden; }
.band-dark .scrim { position: absolute; inset: 0; z-index: 1; background: linear-gradient(180deg, rgba(4,24,56,.88), rgba(5,30,74,.8) 50%, rgba(4,24,56,.92)); }
.band-dark .wrap { position: relative; z-index: 2; }
.band-dark h2 { color: #fff; }
.band-dark p { color: var(--snow-2); }
.gauge-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 34px; margin-top: 56px; }
.gauge-card { text-align: center; padding: 30px 22px 26px; border: 1px solid rgba(91,171,181,.35); border-radius: var(--radius); background: rgba(4,24,56,.5); }
.gauge-card svg { width: 148px; height: 92px; margin: 0 auto 10px; display: block; }
.gauge-card .g-arc { stroke: rgba(184,205,226,.28); }
.gauge-card .g-fill { stroke: var(--teal-light); stroke-dasharray: 180; stroke-dashoffset: 180; }
.gauge-card.lit .g-fill { animation: gfill 1.4s ease-out forwards; }
@keyframes gfill { to { stroke-dashoffset: var(--g-off, 40); } }
.gauge-card .g-needle { transform-origin: 74px 84px; transform: rotate(-90deg); }
.gauge-card.lit .g-needle { animation: gneedle 1.4s cubic-bezier(.2,.8,.3,1) forwards; }
@keyframes gneedle { to { transform: rotate(var(--g-rot, 20deg)); } }
.gauge-title { font-family: var(--font-display); font-weight: 700; font-size: .92rem; letter-spacing: .08em; text-transform: uppercase; color: #fff; }
.gauge-text { font-size: .86rem; color: var(--snow-2); margin: 8px auto 0; max-width: 34ch; }
.reg-list { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 44px; }
.reg-chip {
  font-family: var(--font-meter); font-size: .72rem; letter-spacing: .1em;
  color: var(--snow); border: 1px solid rgba(91,171,181,.5); border-radius: 2px;
  padding: 7px 14px; background: rgba(39,138,146,.14);
}
.illustrative { font-family: var(--font-meter); font-size: .6rem; letter-spacing: .14em; text-transform: uppercase; color: var(--snow-2); opacity: .8; }

/* ---------- why panel schedule ---------- */
.schedule { border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; margin-top: 48px; transition: box-shadow .2s ease-out; }
.schedule:hover { box-shadow: 0 8px 24px rgba(10,56,124,.12); }
.schedule-row { display: grid; grid-template-columns: 240px 1fr; border-top: 1px solid var(--line); background: var(--paper); }
.schedule-row:first-child { border-top: none; }
.schedule-key {
  padding: 24px 26px; background: var(--deck);
  font-family: var(--font-display); font-weight: 700; font-size: .8rem;
  letter-spacing: .18em; text-transform: uppercase; color: var(--navy);
  border-right: 1px solid var(--line); display: flex; align-items: center;
}
.schedule-val { padding: 24px 30px; color: var(--ink-2); }
.schedule-val strong { color: var(--ink); }

/* ---------- contact ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; margin-top: 40px; align-items: start; }
.contact-card { border: 1px solid var(--line); border-radius: var(--radius); padding: 34px 36px; background: var(--paper); transition: box-shadow .2s ease-out; }
.contact-card:hover { box-shadow: 0 8px 24px rgba(10,56,124,.14); }
.contact-card dt { font-family: var(--font-display); font-weight: 700; font-size: .7rem; letter-spacing: .22em; text-transform: uppercase; color: var(--ink-2); margin-top: 20px; }
.contact-card dt:first-child { margin-top: 0; }
.contact-card dd { font-family: var(--font-meter); font-size: 1rem; margin-top: 4px; }
.social-row { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 10px; }
.social-row a {
  font-family: var(--font-display); font-weight: 600; font-size: .74rem;
  letter-spacing: .12em; text-transform: uppercase;
  border: 1px solid var(--line); padding: 7px 13px; border-radius: 2px; color: var(--teal-dark);
}
.social-row a:hover { border-color: var(--teal); }

/* ---------- footer ---------- */
.footer { position: relative; color: var(--snow); }
.footer .scrim { position: absolute; inset: 0; z-index: 1; background: linear-gradient(180deg, rgba(4,24,56,.9), rgba(4,24,56,.96)); }
.footer-inner { position: relative; z-index: 2; padding-block: 76px 34px; }
.footer-tagline { max-width: min(420px, 100%); height: auto; margin-bottom: 44px; }
.footer-cols { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 44px; }
.footer h4 { font-family: var(--font-display); font-weight: 700; font-size: .74rem; letter-spacing: .22em; text-transform: uppercase; color: var(--teal-light); margin-bottom: 16px; }
.footer ul { list-style: none; }
.footer li { margin-bottom: 9px; }
.footer a { color: var(--snow-2); font-size: .9rem; }
.footer a:hover { color: #fff; }
.footer-legal {
  margin-top: 56px; padding-top: 24px; border-top: 1px solid rgba(91,171,181,.3);
  font-size: .78rem; color: var(--snow-2); display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap;
}
.footer-legal p { max-width: none; }

/* ---------- reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease-out, transform .6s ease-out; }
.reveal.lit { opacity: 1; transform: none; }

/* ---------- responsive ---------- */
@media (max-width: 980px) {
  .hex { --hw: 236px; }
  .footer-cols { grid-template-columns: 1fr 1fr; }
  .gauge-grid { grid-template-columns: 1fr; max-width: 420px; margin-left: auto; margin-right: auto; }
  .prod-row { grid-template-columns: 1fr; gap: 16px; }
  .contact-grid { grid-template-columns: 1fr; }
  .meter-strip .wrap { flex-direction: column; }
  .meter-cell { max-width: none; border-left: none; border-top: 1px solid rgba(91,171,181,.25); }
  .meter-cell:first-child { border-top: none; }
  .hero { padding-bottom: 40px; }
  .hero-scroll { display: none; }
  .meter-strip { position: static; margin-top: 48px; }
}
@media (max-width: 1080px) {
  .nav-links {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    background: var(--navy-deep); flex-direction: column; padding: 22px 28px; gap: 18px;
    border-top: 1px solid rgba(91,171,181,.3);
  }
  .nav-links.open { display: flex; }
  .nav-toggle { display: block; }
  .nav { background: var(--navy-deep); padding: 10px 0; }
}
@media (max-width: 900px) {
  /* 3-across honeycomb needs ~808px; stack before it can overflow */
  .hex-row { flex-direction: column; align-items: center; gap: 18px; }
  .hex-row + .hex-row { margin-top: 18px; }
  .hex { --hw: 268px; }
}
@media (max-width: 640px) {
  section { padding: 64px 0; }
  .schedule-row { grid-template-columns: 1fr; }
  .schedule-key { border-right: none; border-bottom: 1px solid var(--line); }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .mimic .flow-path { stroke-dashoffset: 0; animation: none; }
  .mimic .node-lamp, .mimic.lit .node-lamp { opacity: 1; animation: none; }
  .gauge-card .g-fill { stroke-dashoffset: var(--g-off, 40); animation: none !important; }
  .gauge-card .g-needle { transform: rotate(var(--g-rot, 20deg)); animation: none !important; }
  .btn, .hex .scrim { transition: none; }
}