/* Scuba Complete Guide — main stylesheet */
:root {
  --navy: #0b3954;
  --navy-2: #08283b;
  --teal: #0e7c86;
  --teal-2: #1aa3b0;
  --aqua: #e6f6f8;
  --coral: #ff6b4a;
  --coral-2: #e5512f;
  --sand: #fbf7f0;
  --ink: #16242e;
  --muted: #55656f;
  --line: #dde6ea;
  --bg: #ffffff;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(11, 57, 84, .06), 0 8px 24px rgba(11, 57, 84, .08);
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --serif: Georgia, "Iowan Old Style", "Times New Roman", serif;
}
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 84px; }
body { margin: 0; font-family: var(--font); color: var(--ink); background: var(--bg); line-height: 1.65; font-size: 17px; }
img { max-width: 100%; height: auto; display: block; }
a { color: var(--teal); text-underline-offset: 3px; }
a:hover { color: var(--navy); }
h1, h2, h3, h4 { line-height: 1.2; color: var(--navy); letter-spacing: -.01em; }
.wrap { width: min(1180px, 100% - 32px); margin-inline: auto; }
.skip { position: absolute; left: -999px; top: 8px; background: var(--navy); color: #fff; padding: 8px 12px; z-index: 100; border-radius: 6px; }
.skip:focus { left: 8px; }
:focus-visible { outline: 3px solid var(--coral); outline-offset: 2px; }

/* ---------- header ---------- */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.96); backdrop-filter: saturate(160%) blur(8px); border-bottom: 1px solid var(--line); }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 66px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--navy); font-size: 19px; letter-spacing: -.02em; white-space: nowrap; }
.brand b { color: var(--teal); font-weight: 800; }
.brand span { font-weight: 600; }
.logo-mark { width: 38px; height: 38px; flex: none; }
.site-nav ul { list-style: none; display: flex; gap: 2px; margin: 0; padding: 0; }
.site-nav a { display: block; padding: 8px 10px; border-radius: 8px; text-decoration: none; color: var(--ink); font-weight: 600; font-size: 15px; }
.site-nav a:hover, .site-nav a[aria-current] { background: var(--aqua); color: var(--navy); }
.nav-toggle { display: none; background: none; border: 0; width: 44px; height: 44px; padding: 10px; cursor: pointer; }
.nav-toggle span { display: block; height: 2px; background: var(--navy); margin: 5px 0; border-radius: 2px; transition: .2s; }
@media (max-width: 1080px) {
  .nav-toggle { display: block; }
  .site-nav { position: absolute; left: 0; right: 0; top: 100%; background: #fff; border-bottom: 1px solid var(--line); box-shadow: var(--shadow); display: none; }
  .site-nav.open { display: block; }
  .site-nav ul { flex-direction: column; padding: 8px 16px 16px; }
  .site-nav a { padding: 12px; font-size: 17px; }
  .nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
}

/* ---------- breadcrumbs ---------- */
.crumbs ol { list-style: none; display: flex; flex-wrap: wrap; gap: 4px; padding: 0; margin: 0 0 14px; font-size: 14px; color: var(--muted); }
.crumbs li + li::before { content: "›"; margin-right: 4px; opacity: .6; }
.crumbs a { color: inherit; }

/* ---------- home ---------- */
.home-hero { position: relative; color: #fff; background: var(--navy-2); overflow: hidden; }
.home-hero img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: .72; }
.home-hero::after { content: ""; position: absolute; inset: 0; background: linear-gradient(90deg, rgba(8,40,59,.92) 0%, rgba(8,40,59,.6) 50%, rgba(8,40,59,.1) 100%); }
.home-hero .wrap { position: relative; z-index: 1; padding: 96px 0 104px; }
.home-hero h1 { color: #fff; font-size: clamp(34px, 5.4vw, 60px); max-width: 15ch; margin: 0 0 16px; }
.home-hero p { font-size: clamp(17px, 2vw, 21px); max-width: 44ch; margin: 0 0 28px; color: #e6f4f7; }
.btns { display: flex; flex-wrap: wrap; gap: 12px; }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 13px 22px; border-radius: 999px; font-weight: 700; text-decoration: none; border: 2px solid transparent; transition: .15s; font-size: 16px; cursor: pointer; font-family: inherit; }
.btn-primary { background: var(--coral); color: #fff; }
.btn-primary:hover { background: var(--coral-2); color: #fff; }
.btn-ghost { border-color: rgba(255,255,255,.7); color: #fff; }
.btn-ghost:hover { background: #fff; color: var(--navy); }
.btn-outline { border-color: var(--teal); color: var(--teal); background: #fff; }
.btn-outline:hover { background: var(--teal); color: #fff; }
.band { padding: 64px 0; }
.band-alt { background: var(--sand); }
.band-dark { background: var(--navy); color: #dcebf0; }
.band-dark h2, .band-dark h3 { color: #fff; }
.band h2.band-title { font-size: clamp(26px, 3.2vw, 36px); margin: 0 0 8px; }
.band .band-sub { color: var(--muted); margin: 0 0 32px; max-width: 62ch; }
.band-dark .band-sub { color: #b9d3dc; }
.path { list-style: none; counter-reset: step; display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px; padding: 0; margin: 0; }
.path li { counter-increment: step; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 20px; position: relative; }
.path li::before { content: counter(step); display: grid; place-items: center; width: 34px; height: 34px; border-radius: 50%; background: var(--teal); color: #fff; font-weight: 800; margin-bottom: 12px; }
.path h3 { margin: 0 0 6px; font-size: 18px; }
.path p { margin: 0 0 10px; color: var(--muted); font-size: 15px; }
.path a { font-weight: 700; font-size: 15px; }
.section-tiles { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 800px) { .section-tiles { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .section-tiles { grid-template-columns: 1fr; } }
.tile { position: relative; border-radius: var(--radius); overflow: hidden; text-decoration: none; color: #fff; aspect-ratio: 16/10; background: var(--navy); }
.tile img { width: 100%; height: 100%; object-fit: cover; transition: transform .4s; }
.tile:hover img { transform: scale(1.05); }
.tile-body { position: absolute; inset: auto 0 0 0; padding: 40px 16px 14px; background: linear-gradient(transparent, rgba(8,40,59,.9)); display: flex; flex-direction: column; }
.tile strong { font-size: 19px; }
.tile small { opacity: .85; }
.tools-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.tool-card { background: rgba(255,255,255,.06); border: 1px solid rgba(255,255,255,.15); border-radius: var(--radius); padding: 22px; text-decoration: none; color: #dcebf0; transition: .15s; }
.tool-card:hover { background: rgba(255,255,255,.12); color: #fff; }
.tool-card .ico { font-size: 28px; line-height: 1; }
.tool-card h3 { margin: 10px 0 6px; font-size: 18px; }
.tool-card p { margin: 0; font-size: 15px; }
.trust { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 24px; }
.trust h3 { margin: 0 0 6px; font-size: 18px; }
.trust p { margin: 0; color: var(--muted); }

/* ---------- cards ---------- */
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 20px; }
.card { display: flex; flex-direction: column; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; text-decoration: none; color: var(--ink); transition: transform .15s, box-shadow .15s; }
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); color: var(--ink); }
.card-img { aspect-ratio: 16/9; object-fit: cover; width: 100%; }
.card-body { padding: 16px 18px 20px; }
.card-kicker { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--teal); font-weight: 700; }
.card h2, .card h3 { font-size: 19px; margin: 6px 0 8px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.55; }

/* ---------- hub ---------- */
.hub-hero { background: linear-gradient(rgba(8,40,59,.74), rgba(8,40,59,.88)), var(--hero) center/cover no-repeat var(--navy); color: #fff; padding: 56px 0 60px; }
.hub-hero h1 { color: #fff; font-size: clamp(32px, 4.6vw, 50px); margin: 0 0 12px; }
.hub-hero .lede { color: #dcebf0; max-width: 64ch; font-size: 19px; margin: 0; }
.hub-hero .crumbs ol { color: #b9d3dc; }
.hub { padding: 40px 0 72px; }
.hub-intro { max-width: 760px; margin-bottom: 32px; }

/* ---------- article ---------- */
.article-hero { background: var(--aqua); padding: 36px 0 30px; border-bottom: 1px solid var(--line); }
.article-hero h1 { font-size: clamp(30px, 4.4vw, 46px); margin: 0 0 12px; max-width: 24ch; }
.article-hero .lede { font-size: 19px; color: #33464f; max-width: 70ch; margin: 0 0 14px; }
.byline { font-size: 14px; color: var(--muted); margin: 0; }
.article-grid { display: grid; grid-template-columns: minmax(0, 760px) 300px; gap: 48px; justify-content: space-between; padding-top: 32px; }
.hero-fig { margin: 0 0 24px; border-radius: var(--radius); overflow: hidden; background: var(--aqua); }
.hero-fig img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.article-side { position: relative; }
.side-box { position: sticky; top: 90px; border: 1px solid var(--line); border-radius: var(--radius); padding: 18px 18px 10px; background: #fff; }
.side-box h2 { font-size: 15px; text-transform: uppercase; letter-spacing: .06em; margin: 0 0 10px; color: var(--teal); }
.side-list { margin: 0; padding-left: 20px; font-size: 15px; }
.side-list li { margin-bottom: 8px; }
.side-list a { color: var(--ink); text-decoration: none; }
.side-list a:hover { color: var(--teal); text-decoration: underline; }
.side-list a[aria-current] { font-weight: 700; color: var(--teal); }
@media (max-width: 1000px) { .article-grid { grid-template-columns: minmax(0, 1fr); gap: 0; } .article-side { margin-top: 32px; } .side-box { position: static; } }
.toc { border: 1px solid var(--line); border-radius: var(--radius); padding: 14px 18px; margin: 0 0 28px; background: #fbfdfd; }
.toc summary { font-weight: 700; cursor: pointer; color: var(--navy); }
.toc ol { margin: 10px 0 4px; padding-left: 22px; columns: 2; column-gap: 32px; font-size: 15px; }
.toc li { margin-bottom: 6px; break-inside: avoid; }
@media (max-width: 640px) { .toc ol { columns: 1; } }

/* ---------- prose ---------- */
.prose { font-size: 18px; }
.prose > * { max-width: 100%; }
.prose h2 { font-size: clamp(24px, 3vw, 30px); margin: 44px 0 14px; padding-top: 4px; }
.prose h3 { font-size: 21px; margin: 30px 0 10px; }
.prose p, .prose ul, .prose ol { margin: 0 0 18px; }
.prose li { margin-bottom: 8px; }
.prose li::marker { color: var(--teal); }
.prose strong { color: #0f2a3a; }
.prose blockquote { margin: 24px 0; padding: 4px 0 4px 20px; border-left: 4px solid var(--teal-2); font-family: var(--serif); font-size: 20px; color: #2c4250; }
.prose figure { margin: 28px 0; }
.prose figcaption { font-size: 14px; color: var(--muted); margin-top: 8px; }
.prose figure img { border-radius: var(--radius); }
.prose dl:not(.keyfacts) { margin: 0 0 24px; }
.prose dl:not(.keyfacts) dt { margin-top: 14px; color: var(--navy); }
.prose dl:not(.keyfacts) dd { margin: 2px 0 0; }
.prose .lede, .page .lede { font-size: 20px; color: #33464f; }
.small { font-size: 14px; color: var(--muted); }
.table-wrap { overflow-x: auto; margin: 0 0 24px; border: 1px solid var(--line); border-radius: 12px; }
.prose table, .tool table { width: 100%; border-collapse: collapse; font-size: 15.5px; }
.prose th, .prose td, .tool th, .tool td { padding: 10px 12px; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; }
.prose th, .tool th { background: var(--aqua); color: var(--navy); font-weight: 700; white-space: nowrap; }
.prose tr:last-child td { border-bottom: 0; }
.callout { border-radius: 12px; padding: 16px 20px; margin: 24px 0; background: var(--aqua); border-left: 5px solid var(--teal); font-size: 17px; }
.callout > :last-child { margin-bottom: 0; }
.callout-title { display: block; font-weight: 800; color: var(--navy); margin-bottom: 4px; }
.callout.warn { background: #fff4ef; border-color: var(--coral); }
.callout.tip { background: #f1f9ee; border-color: #3f9b4e; }
.callout.info { background: var(--aqua); }
.keyfacts { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 0; background: #fff; border: 1px solid var(--line); border-radius: 12px; overflow: hidden; margin: 0 0 28px; }
.keyfacts div { background: #fff; padding: 12px 14px; box-shadow: 0 0 0 .5px var(--line); }
.keyfacts dt { font-size: 12px; text-transform: uppercase; letter-spacing: .07em; color: var(--muted); font-weight: 700; }
.keyfacts dd { margin: 2px 0 0; font-weight: 700; color: var(--navy); font-size: 16px; line-height: 1.4; }
.rating { display: inline-block; padding: 2px 10px; border-radius: 999px; font-size: 14px; font-weight: 700; background: #e6f4ea; color: #1e6b31; }
.rating.mid { background: #fff5d6; color: #7a5a00; }
.rating.adv { background: #ffe8e1; color: #a1341a; }
.checks { list-style: none; padding-left: 0 !important; }
.checks li { position: relative; padding-left: 30px; }
.checks li::before { content: "✓"; position: absolute; left: 0; top: 0; color: #fff; background: var(--teal); width: 20px; height: 20px; border-radius: 50%; display: grid; place-items: center; font-size: 12px; font-weight: 900; margin-top: 4px; }
.crosses li::before { content: "✕"; background: var(--coral); }
.proscons { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin: 0 0 24px; }
.proscons > div { border: 1px solid var(--line); border-radius: 12px; padding: 14px 18px; }
.proscons h4 { margin: 0 0 8px; font-size: 16px; }
.proscons ul { margin: 0; padding-left: 20px; font-size: 16px; }
@media (max-width: 640px) { .proscons { grid-template-columns: 1fr; } }
.faq details { border: 1px solid var(--line); border-radius: 12px; margin-bottom: 10px; background: #fff; }
.faq summary { cursor: pointer; padding: 14px 18px; font-weight: 700; color: var(--navy); list-style: none; position: relative; padding-right: 44px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 18px; top: 10px; font-size: 24px; color: var(--teal); }
.faq details[open] summary::after { content: "–"; }
.faq details > :not(summary) { padding: 0 18px; }
.faq details > p:last-child { padding-bottom: 14px; margin-bottom: 0; }
.signals { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: 12px; margin: 0 0 24px; padding: 0 !important; list-style: none; }
.signals li { border: 1px solid var(--line); border-radius: 12px; padding: 14px; margin: 0; font-size: 16px; }
.signals strong { display: block; color: var(--navy); }

/* ---------- pager, related ---------- */
.pager { display: flex; justify-content: space-between; gap: 16px; margin: 48px 0 0; padding-top: 24px; border-top: 1px solid var(--line); }
.pager a { display: flex; flex-direction: column; text-decoration: none; font-weight: 700; max-width: 48%; }
.pager a span { font-size: 13px; text-transform: uppercase; letter-spacing: .07em; color: var(--muted); font-weight: 600; }
.pager .next { text-align: right; margin-left: auto; }
.related { padding: 56px 0 72px; }
.related > h2 { font-size: 28px; margin: 0 0 20px; }

/* ---------- ads ---------- */
.ad { margin: 32px 0; min-height: 120px; text-align: center; }
.ad-label { display: block; font-size: 11px; text-transform: uppercase; letter-spacing: .1em; color: #8a99a2; margin-bottom: 4px; }
.ad-side { position: sticky; top: 420px; }

/* ---------- plain pages ---------- */
.page { padding: 36px 0 72px; max-width: 800px; }
.page h1 { font-size: clamp(30px, 4vw, 42px); }

/* ---------- tools ---------- */
.tool { border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; margin: 0 0 32px; background: #fbfdfd; font-size: 16px; }
.tool label { font-weight: 700; color: var(--navy); display: block; margin-bottom: 6px; }
.tool select, .tool input[type=number] { font: inherit; padding: 10px 12px; border: 1px solid #b9cbd3; border-radius: 10px; background: #fff; min-width: 140px; }
.tool .row { display: flex; flex-wrap: wrap; gap: 18px; align-items: flex-end; margin-bottom: 18px; }
.tool .seg { display: inline-flex; border: 1px solid #b9cbd3; border-radius: 10px; overflow: hidden; }
.tool .seg button { font: inherit; border: 0; background: #fff; padding: 10px 14px; cursor: pointer; }
.tool .seg button[aria-pressed="true"] { background: var(--teal); color: #fff; }
.months { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 18px; }
.months button { font: inherit; font-size: 15px; border: 1px solid #b9cbd3; background: #fff; border-radius: 999px; padding: 6px 13px; cursor: pointer; }
.months button[aria-pressed="true"] { background: var(--navy); border-color: var(--navy); color: #fff; }
.result { border-radius: 12px; background: #fff; border: 2px solid var(--teal); padding: 18px 20px; }
.result h3 { margin: 0 0 6px; font-size: 22px; }
.result p { margin: 0 0 8px; }
.cal-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 12px; }
.cal-item { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.cal-item h4 { margin: 0 0 4px; font-size: 17px; }
.cal-item p { margin: 0; font-size: 14.5px; color: var(--muted); }
.cal-item a { font-size: 14.5px; font-weight: 700; }
.badge { display: inline-block; font-size: 12px; font-weight: 800; padding: 2px 8px; border-radius: 999px; margin-left: 6px; vertical-align: middle; }
.badge.best { background: #e6f4ea; color: #1e6b31; }
.badge.good { background: #fff5d6; color: #7a5a00; }
.heat td { text-align: center; font-size: 13px; padding: 6px 4px; }
.heat td:first-child { text-align: left; font-weight: 600; white-space: nowrap; font-size: 14px; }
.heat .b { background: #37a45a; color: #fff; }
.heat .g { background: #cde9d5; }
.heat .o { background: #f1f4f5; color: #9aa7ae; }
.checklist fieldset { border: 1px solid var(--line); border-radius: 12px; padding: 12px 18px 8px; margin: 0 0 16px; background: #fff; }
.checklist legend { font-weight: 800; color: var(--navy); padding: 0 6px; }
.checklist label { display: flex; gap: 10px; align-items: flex-start; font-weight: 400; color: var(--ink); padding: 5px 0; cursor: pointer; }
.checklist input { width: 20px; height: 20px; margin-top: 3px; accent-color: var(--teal); flex: none; }
.checklist label:has(input:checked) { color: #8a99a2; text-decoration: line-through; }
.progress { height: 10px; background: var(--line); border-radius: 999px; overflow: hidden; margin: 6px 0 18px; }
.progress span { display: block; height: 100%; background: var(--teal); width: 0; transition: width .2s; }

/* ---------- footer ---------- */
.site-footer { background: var(--navy-2); color: #b9d3dc; padding: 56px 0 32px; font-size: 15px; }
.site-footer a { color: #dcebf0; text-decoration: none; }
.site-footer a:hover { color: #fff; text-decoration: underline; }
.brand-light { color: #fff; }
.brand-light b { color: var(--teal-2); }
.footer-brand p { max-width: 50ch; margin: 12px 0 32px; }
.footer-cols { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 28px; }
.footer-cols h3 { font-size: 15px; margin: 0 0 10px; }
.footer-cols h3 a { color: #fff; }
.footer-cols ul { list-style: none; padding: 0; margin: 0; }
.footer-cols li { margin-bottom: 6px; }
.footer-legal { border-top: 1px solid rgba(255,255,255,.12); margin-top: 40px; padding-top: 24px; }
.footer-legal nav { display: flex; flex-wrap: wrap; gap: 18px; margin: 16px 0; }
.disclaimer { font-size: 14px; max-width: 90ch; }

@media (max-width: 640px) {
  body { font-size: 16.5px; }
  .prose { font-size: 17px; }
  .home-hero .wrap { padding: 64px 0 72px; }
  .band { padding: 48px 0; }
  .brand { font-size: 17px; }
  .logo-mark { width: 34px; height: 34px; }
}
@media print {
  .site-header, .site-footer, .ad, .article-side, .related, .pager, .toc, .btns, .no-print { display: none !important; }
  body { font-size: 12pt; }
}