/* Black Water Tek marketing site. Dark instrument-panel aesthetic, brand tokens.
   No glows, no pulses, no animated gradients, no em dashes. */
:root {
  --bg: #060e1a;
  --surface: #0a1625;
  --panel: #0d1e30;
  --panel2: #0f2540;
  --border: #1a3050;
  --navy: #0f3862;
  --navyL: #1a4d80;
  --steel: #9eafc1;
  --steel-dim: #6a85a0;
  --text: #dceaf5;
  --muted: #5a7a95;
  --cyan: #4db8d4;
  --safe: #3dc98a;
  --warn: #e09a30;
  --o2: #34d399;
  --he: #f97316;
  --font: 'Montserrat', system-ui, -apple-system, sans-serif;
  --mono: 'Roboto Mono', ui-monospace, monospace;
}

* { box-sizing: border-box; }
img { max-width: 100%; }
picture { display: contents; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-weight: 300;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--cyan); text-decoration: none; }
h1, h2, h3 { font-weight: 300; letter-spacing: 0.5px; }
.wrap { max-width: 1120px; margin: 0 auto; padding: 0 24px; }
.eyebrow { font-size: 11px; letter-spacing: 3px; text-transform: uppercase; color: var(--steel); margin: 0 0 12px; }

/* Nav */
header.nav {
  position: sticky; top: 0; z-index: 10;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { display: flex; align-items: center; gap: 11px; }
.brand img { width: 34px; height: 34px; border-radius: 8px; }
.brand b { font-weight: 200; letter-spacing: 5px; text-transform: uppercase; font-size: 16px; }
.nav-links { display: flex; gap: 26px; align-items: center; }
.nav-links a { color: var(--steel); font-size: 13px; letter-spacing: 0.5px; }
.nav-links a:hover { color: var(--text); }
@media (max-width: 760px) { .nav-links { display: none; } }

.btn {
  display: inline-block;
  padding: 12px 22px;
  border-radius: 8px;
  font-size: 13px; letter-spacing: 1px; text-transform: uppercase;
  background: linear-gradient(135deg, var(--navy), var(--navyL));
  color: #eef6fc;
  border: 1px solid #9eafc155;
}
.btn:hover { border-color: var(--cyan); }
.btn.ghost { background: none; border: 1px solid var(--border); color: var(--steel); }
.btn.ghost:hover { border-color: var(--cyan); color: var(--cyan); }

/* Hero, deep-water visual treatment (static, on-brand: light from the surface
   fading into the depths). Drop a real photo at img/hero.jpg to layer it in. */
.hero {
  padding: 96px 0 76px; border-bottom: 1px solid var(--border); position: relative; overflow: hidden;
  background:
    radial-gradient(120% 90% at 50% -10%, rgba(77,184,212,0.16), transparent 55%),
    linear-gradient(180deg, #0a1830 0%, var(--bg) 70%);
}
.hero::after {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0.5;
  background-image:
    radial-gradient(3px 3px at 12% 70%, rgba(220,234,245,0.35), transparent),
    radial-gradient(2px 2px at 24% 82%, rgba(220,234,245,0.30), transparent),
    radial-gradient(2px 2px at 70% 60%, rgba(220,234,245,0.25), transparent),
    radial-gradient(3px 3px at 84% 78%, rgba(220,234,245,0.30), transparent),
    radial-gradient(2px 2px at 56% 88%, rgba(220,234,245,0.22), transparent);
}
.hero > .wrap { position: relative; z-index: 1; }
.hero-photo {
  display: block; width: 100%; height: auto; max-width: 1120px; margin: 28px auto 0; border-radius: 12px;
  border: 1px solid var(--border); aspect-ratio: 21/9; object-fit: cover; background: var(--surface);
}
/* Product image slot (drop img/gas-guru.jpg, img/dts-planner.jpg). */
.shot { display: block; width: 100%; height: auto; aspect-ratio: 16/10; object-fit: cover; border-radius: 10px; border: 1px solid var(--border); background: var(--surface); margin-bottom: 16px; }
.hero h1 { font-size: 46px; line-height: 1.1; margin: 0 0 18px; max-width: 14ch; }
.hero h1 b { font-weight: 500; color: var(--cyan); }
.hero p { font-size: 18px; color: var(--steel); max-width: 56ch; margin: 0 0 28px; }
.hero .cta { display: flex; gap: 14px; flex-wrap: wrap; }
@media (max-width: 600px) { .hero h1 { font-size: 34px; } }

section { padding: 64px 0; border-bottom: 1px solid var(--border); }
section h2 { font-size: 30px; margin: 0 0 8px; }
section > .wrap > p.lead { color: var(--steel); max-width: 60ch; margin: 0 0 36px; }

/* Cards */
.grid { display: grid; gap: 18px; }
.cols-2 { grid-template-columns: repeat(2, 1fr); }
.cols-3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 860px) { .cols-2, .cols-3 { grid-template-columns: 1fr; } }
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 26px;
}
.card h3 { font-size: 20px; margin: 0 0 6px; }
.card .tag { display: inline-block; font-size: 10px; letter-spacing: 1.5px; text-transform: uppercase; padding: 3px 9px; border-radius: 20px; border: 1px solid var(--border); color: var(--steel); margin-bottom: 14px; }
.card .tag.live { color: var(--safe); border-color: #3dc98a55; }
.card ul { margin: 14px 0 0; padding-left: 18px; color: var(--steel); font-size: 14px; }
.card ul li { margin-bottom: 6px; }

/* Feature list */
.feat { display: flex; gap: 14px; align-items: flex-start; }
.feat .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--cyan); margin-top: 7px; flex-shrink: 0; }
.feat h4 { margin: 0 0 4px; font-size: 15px; font-weight: 400; }
.feat p { margin: 0; font-size: 13px; color: var(--muted); }

/* Full-width photo breaker */
.breaker { position: relative; padding: 0; border-bottom: 1px solid var(--border); overflow: hidden; }
.breaker img { display: block; width: 100%; height: 360px; object-fit: cover; filter: saturate(0.92) brightness(0.82); }
.breaker-caption { position: absolute; inset: 0; display: flex; align-items: flex-end; padding-bottom: 36px;
  background: linear-gradient(180deg, rgba(6,14,26,0.30) 0%, rgba(6,14,26,0.10) 40%, rgba(6,14,26,0.85) 100%); }
.breaker-caption h2 { font-size: 30px; margin: 0; max-width: 18ch; }
@media (max-width: 600px) { .breaker > img { height: 260px; } .breaker-caption h2 { font-size: 23px; } }

/* Engine split (copy + photo) */
.engine-split { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 40px; align-items: center; }
.engine-split .lead { margin-bottom: 28px; }
.engine-figure { margin: 0; }
.engine-figure img { width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--border); display: block; }
.engine-figure figcaption { font-size: 12px; color: var(--muted); margin-top: 10px; line-height: 1.5; }
@media (max-width: 860px) { .engine-split { grid-template-columns: 1fr; gap: 28px; } }

/* Built by a diver */
.about-split { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: 40px; align-items: center; }
.about-figure { margin: 0; }
.about-figure img { width: 100%; height: auto; border-radius: 12px; border: 1px solid var(--border); display: block; filter: grayscale(0.15); }
.about-copy .lead { margin-bottom: 22px; }
.about-facts { list-style: none; padding: 0; margin: 0; }
.about-facts li { padding: 11px 0; border-bottom: 1px solid var(--border); font-size: 14px; color: var(--steel); }
.about-facts li:last-child { border-bottom: none; }
.about-facts b { font-family: var(--mono); color: var(--cyan); font-weight: 500; margin-right: 8px; }
@media (max-width: 860px) { .about-split { grid-template-columns: 1fr; gap: 26px; } }

/* Engine stats */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
@media (max-width: 760px) { .stats { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 860px) { .engine-split .stats { grid-template-columns: repeat(2, 1fr); } }
.stat { background: var(--surface); border: 1px solid var(--border); border-radius: 10px; padding: 20px; text-align: center; }
.stat .n { font-family: var(--mono); font-size: 26px; color: var(--cyan); }
.stat .l { font-size: 11px; letter-spacing: 1px; text-transform: uppercase; color: var(--muted); margin-top: 6px; }

/* Pricing */
.price { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; padding: 28px; }
.price.featured { border-color: var(--cyan); }
.price h3 { font-size: 16px; letter-spacing: 2px; text-transform: uppercase; color: var(--steel); }
.price .amt { font-family: var(--mono); font-size: 34px; margin: 8px 0 2px; }
.price .amt span { font-size: 13px; color: var(--muted); }
.price ul { list-style: none; padding: 0; margin: 18px 0; }
.price ul li { padding: 7px 0; border-bottom: 1px solid var(--border); font-size: 13px; color: var(--steel); }
.price ul li::before { content: '+ '; color: var(--safe); font-family: var(--mono); }

/* FAQ */
.faq { max-width: 820px; }
.faq details { border: 1px solid var(--border); border-radius: 10px; background: var(--panel); margin-bottom: 12px; }
.faq summary {
  list-style: none; cursor: pointer; padding: 18px 22px; font-size: 16px; color: var(--text);
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: '+'; font-family: var(--mono); color: var(--cyan); font-size: 20px; line-height: 1; flex-shrink: 0; }
.faq details[open] summary::after { content: '\2212'; }
.faq summary:hover { color: var(--cyan); }
.faq details p { margin: 0; padding: 0 22px 20px; color: var(--steel); font-size: 14px; line-height: 1.65; }

/* Footer */
footer { padding: 40px 0; color: var(--muted); font-size: 12px; }
footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 14px; }
.disclaimer { font-size: 11px; color: var(--steel-dim); max-width: 70ch; margin-top: 10px; line-height: 1.5; }