/* ==========================================================================
   Hull Diving Services — Design System v3
   Logo-blue headings, no harsh black, simple top-to-bottom sections.
   ========================================================================== */

:root {
  /* Palette — built from the HDS logo blue */
  --paper: #f8fafd;        /* page background */
  --white: #ffffff;
  --blue: #0e5aa7;         /* logo royal blue — headings, buttons, accents */
  --blue-deep: #0b477f;    /* hover / darker blue */
  --blue-soft: #e8f1fb;    /* tinted panels */
  --navy: #123a5e;         /* strong text that isn't a heading */
  --text: #44607c;         /* body text — blue-grey */
  --text-soft: #7d92a8;    /* muted */
  --hairline: #dde7f1;
  --hairline-dark: rgba(255,255,255,.16);
  --dark: #0a2036;         /* CTA band + footer */

  /* System */
  --maxw: 1200px;
  --gutter: clamp(20px, 5vw, 56px);
  --r: 6px;
  --shadow: 0 8px 30px rgba(14, 90, 167, .09);
  --ease: cubic-bezier(.25, .6, .3, 1);

  --font-body: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --font-head: "Inter Tight", var(--font-body);
}

/* ------------------------------ Reset ---------------------------------- */
*, *::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: .001ms !important; transition-duration: .001ms !important; }
}
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--text);
  background: var(--paper);
  line-height: 1.7;
  font-size: 16.5px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: var(--blue); text-decoration: none; }
h1, h2, h3, h4 {
  font-family: var(--font-head);
  color: var(--blue);
  line-height: 1.1;
  letter-spacing: -.025em;
  margin: 0 0 .5em;
  font-weight: 650;
}
p { margin: 0 0 1em; }
ul { margin: 0; padding: 0; }

h1 { font-size: clamp(2.3rem, 5.6vw, 4rem); }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.6rem); }
h3 { font-size: clamp(1.12rem, 1.8vw, 1.3rem); }
.lead { font-size: clamp(1.02rem, 1.5vw, 1.2rem); line-height: 1.65; }
.muted { color: var(--text-soft); }

/* ------------------------------ Layout --------------------------------- */
.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: var(--gutter); }
.section { padding: clamp(64px, 8.5vw, 116px) 0; }
.section--tint { background: var(--blue-soft); }
.rule { border: 0; border-top: 1px solid var(--hairline); margin: 0; }

/* Centered section head — the one consistent pattern on every page */
.center-head { text-align: center; max-width: 700px; margin: 0 auto clamp(36px, 5vw, 56px); }
.center-head h2 { margin-bottom: 14px; }
.center-head p { margin: 0; }

/* ------------------------------ Buttons -------------------------------- */
.btn {
  display: inline-flex; align-items: center; gap: 11px;
  font-family: var(--font-head); font-weight: 600; font-size: .96rem;
  padding: 15px 30px; border-radius: var(--r); border: 1px solid var(--blue);
  cursor: pointer; transition: background .25s var(--ease), color .25s var(--ease), border-color .25s, transform .25s var(--ease);
  white-space: nowrap;
}
.btn svg { width: 17px; height: 17px; transition: transform .25s var(--ease); }
.btn:hover svg { transform: translateX(4px); }
.btn--solid { background: var(--blue); color: #fff; box-shadow: 0 8px 22px rgba(14, 90, 167, .25); }
.btn--solid:hover { background: var(--blue-deep); border-color: var(--blue-deep); transform: translateY(-2px); }
.btn--line { background: #fff; color: var(--blue); }
.btn--line:hover { background: var(--blue-soft); transform: translateY(-2px); }
.section--dark .btn--solid, .cta-dark .btn--solid { background: #fff; color: var(--blue); border-color: #fff; box-shadow: none; }
.section--dark .btn--solid:hover, .cta-dark .btn--solid:hover { background: var(--blue-soft); border-color: var(--blue-soft); }

.arrow-link {
  display: inline-flex; align-items: center; gap: 9px;
  font-family: var(--font-head); font-weight: 600; font-size: .95rem; color: var(--blue);
  transition: color .2s, gap .25s var(--ease);
}
.arrow-link svg { width: 16px; height: 16px; }
.arrow-link:hover { color: var(--blue-deep); gap: 13px; }

/* ------------------------------ Header --------------------------------- */
.site-header {
  position: fixed; inset: 0 0 auto 0; z-index: 100;
  background: rgba(255, 255, 255, .94); backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color .3s, box-shadow .3s;
}
.site-header.is-scrolled { border-bottom-color: var(--hairline); box-shadow: 0 4px 20px rgba(14, 90, 167, .06); }
.nav { display: flex; align-items: center; justify-content: space-between; height: 80px; gap: 24px; }
.brand { display: flex; align-items: center; }
.brand__logo { height: 44px; width: auto; display: block; }
.footer-brand .brand__logo { background: #fff; padding: 8px 14px; border-radius: var(--r); height: 56px; }

.nav__links { display: flex; align-items: center; gap: 28px; list-style: none; }
.nav__links a {
  font-family: var(--font-head); font-weight: 550; font-size: .95rem;
  color: var(--text); padding: 6px 0; border-bottom: 2px solid transparent;
  transition: color .2s, border-color .2s;
}
.nav__links a:hover { color: var(--blue); }
.nav__links a[aria-current="page"] { color: var(--blue); border-bottom-color: var(--blue); }
.nav__cta a.btn { padding: 12px 24px; font-size: .9rem; }

.nav__toggle {
  display: none; width: 44px; height: 44px; border: 1px solid var(--hairline); border-radius: var(--r);
  background: #fff; cursor: pointer; padding: 0; place-items: center;
}
.nav__toggle span, .nav__toggle span::before, .nav__toggle span::after {
  content: ""; display: block; width: 18px; height: 2px; background: var(--blue); transition: transform .3s, opacity .2s; position: relative;
}
.nav__toggle span::before { position: absolute; top: -6px; }
.nav__toggle span::after { position: absolute; top: 6px; }
body.nav-open .nav__toggle span { background: transparent; }
body.nav-open .nav__toggle span::before { transform: translateY(6px) rotate(45deg); }
body.nav-open .nav__toggle span::after { transform: translateY(-6px) rotate(-45deg); }

@media (max-width: 920px) {
  .nav__toggle { display: grid; }
  .nav__links {
    position: fixed; inset: 80px 0 auto 0; flex-direction: column; align-items: stretch; gap: 0;
    background: #fff; padding: 8px var(--gutter) 28px;
    border-bottom: 1px solid var(--hairline); box-shadow: 0 20px 40px rgba(14, 90, 167, .1);
    transform: translateY(-130%); transition: transform .4s var(--ease);
  }
  body.nav-open .nav__links { transform: translateY(0); }
  .nav__links li { border-bottom: 1px solid var(--hairline); }
  .nav__links li:last-child { border-bottom: 0; }
  .nav__links a { display: block; padding: 16px 4px; }
  .nav__links a[aria-current="page"] { border-bottom: 0; }
  .nav__cta { margin-top: 14px; }
  .nav__cta a.btn { width: 100%; justify-content: center; }
}

/* ------------------------------ Heroes --------------------------------- */
.hero { padding: clamp(140px, 18vh, 190px) 0 clamp(40px, 6vw, 64px); text-align: center; }
.hero h1 { max-width: 21ch; margin-inline: auto; margin-bottom: 20px; }
.hero .lead { max-width: 60ch; margin: 0 auto 30px; }
.hero__actions { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }
.hero__creds {
  display: flex; flex-wrap: wrap; gap: 10px 30px; justify-content: center;
  margin-top: 38px; padding-top: 26px; border-top: 1px solid var(--hairline);
  font-family: var(--font-head); font-size: .8rem; font-weight: 600; letter-spacing: .08em;
  text-transform: uppercase; color: var(--text-soft);
}
.hero__creds span { display: inline-flex; align-items: center; gap: 8px; }
.hero__creds span::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--blue); }

.media-band { position: relative; height: clamp(240px, 40vw, 480px); overflow: hidden; }
.media-band img { width: 100%; height: 100%; object-fit: cover; }

/* Inner page hero */
.page-hero { padding: clamp(140px, 18vh, 185px) 0 clamp(36px, 5vw, 56px); text-align: center; }
.page-hero h1 { max-width: 22ch; margin-inline: auto; margin-bottom: 16px; }
.page-hero .lead { max-width: 62ch; margin: 0 auto; }
.crumbs { display: flex; gap: 10px; justify-content: center; font-family: var(--font-head); font-size: .78rem; letter-spacing: .14em; text-transform: uppercase; color: var(--text-soft); margin-bottom: 20px; }
.crumbs a { color: var(--text-soft); } .crumbs a:hover { color: var(--blue); }

/* ------------------------------ Stat rail ------------------------------ */
.stat-rail { display: grid; grid-template-columns: repeat(2, 1fr); border-top: 1px solid var(--hairline); border-bottom: 1px solid var(--hairline); }
@media (min-width: 760px) { .stat-rail { grid-template-columns: repeat(4, 1fr); } }
.stat-rail > div { padding: clamp(26px, 3vw, 38px) 18px; text-align: center; }
.stat-rail > div + div { border-left: 1px solid var(--hairline); }
@media (max-width: 759px) { .stat-rail > div:nth-child(3) { border-left: 0; } .stat-rail > div:nth-child(1), .stat-rail > div:nth-child(2) { border-bottom: 1px solid var(--hairline); } }
.stat-rail strong { font-family: var(--font-head); display: block; font-size: clamp(1.9rem, 3.4vw, 2.7rem); font-weight: 650; color: var(--blue); line-height: 1.05; margin-bottom: 6px; }
.stat-rail span { font-size: .82rem; letter-spacing: .05em; text-transform: uppercase; color: var(--text-soft); }

/* ------------------------------ Service cards -------------------------- */
.svc-grid { display: grid; gap: 18px; }
@media (min-width: 640px) { .svc-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 980px) { .svc-grid { grid-template-columns: repeat(3, 1fr); } }
.svc-card {
  display: flex; flex-direction: column; gap: 8px;
  background: #fff; border: 1px solid var(--hairline); border-radius: var(--r);
  padding: 28px; transition: transform .3s var(--ease), box-shadow .3s var(--ease), border-color .3s;
}
.svc-card:hover { transform: translateY(-5px); box-shadow: var(--shadow); border-color: #bcd6ef; }
.svc-card h3 { margin: 0; }
.svc-card p { margin: 0 0 6px; font-size: .95rem; color: var(--text); flex: 1; }

/* ------------------------------ Two-column feature --------------------- */
.feature { display: grid; gap: clamp(26px, 4vw, 56px); align-items: center; }
@media (min-width: 900px) { .feature { grid-template-columns: 1fr 1fr; } }
.feature .photo { margin: 0; }
.feature h2 { margin-bottom: 14px; }

/* Photos */
.photo { border-radius: var(--r); overflow: hidden; margin: 0; box-shadow: var(--shadow); }
.photo img { width: 100%; height: auto; display: block; }
.photo--cover img { aspect-ratio: 4/3; object-fit: cover; }

/* Short bullets */
.dashlist { list-style: none; display: grid; gap: 13px; }
.dashlist li { position: relative; padding-left: 28px; }
.dashlist li::before {
  content: ""; position: absolute; left: 0; top: .5em; width: 15px; height: 15px; border-radius: 50%;
  background: var(--blue-soft);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='9' height='9' viewBox='0 0 24 24' fill='none' stroke='%230e5aa7' stroke-width='4' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: center;
}
.dashlist strong { color: var(--navy); font-family: var(--font-head); font-weight: 600; }

/* ------------------------------ Accreditation cards -------------------- */
.cred-grid { display: grid; gap: 18px; grid-template-columns: 1fr; }
@media (min-width: 640px) { .cred-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .cred-grid { grid-template-columns: repeat(4, 1fr); } }
.cred {
  background: #fff; border: 1px solid var(--hairline); border-top: 3px solid var(--blue);
  border-radius: var(--r); padding: 26px; text-align: center;
}
.cred h3 { margin-bottom: 8px; }
.cred p { font-size: .92rem; color: var(--text); margin: 0; }

/* ------------------------------ Gallery -------------------------------- */
.gallery { display: grid; gap: 16px; grid-template-columns: repeat(2, 1fr); }
@media (min-width: 900px) { .gallery { grid-template-columns: repeat(4, 1fr); } }
.gallery figure { margin: 0; border-radius: var(--r); overflow: hidden; box-shadow: var(--shadow); background: var(--blue-soft); }
.gallery img { width: 100%; height: 100%; aspect-ratio: 3/4; object-fit: cover; transition: transform .5s var(--ease); }
.gallery figure:hover img { transform: scale(1.04); }
.gallery img.contain { object-fit: contain; padding: 14px; }

/* ------------------------------ Mission quote -------------------------- */
.mission { background: var(--blue-soft); }
.mission blockquote {
  margin: 0 auto; max-width: 820px; text-align: center;
  font-family: var(--font-head); font-weight: 600; font-size: clamp(1.25rem, 2.6vw, 1.9rem);
  line-height: 1.4; letter-spacing: -.015em; color: var(--blue);
}

/* ------------------------------ Client lists --------------------------- */
.client-cols { column-gap: clamp(30px, 4vw, 60px); columns: 1; }
@media (min-width: 640px) { .client-cols { columns: 2; } }
@media (min-width: 980px) { .client-cols { columns: 3; } }
.client-cols li {
  list-style: none; break-inside: avoid;
  padding: 12px 2px; border-bottom: 1px solid var(--hairline);
  font-size: .96rem; color: var(--text);
}
.sector { margin-bottom: clamp(40px, 5vw, 56px); }
.sector:last-child { margin-bottom: 0; }
.sector h3 { text-align: center; margin-bottom: 20px; }
.sector h3::after { content: ""; display: block; width: 44px; height: 3px; border-radius: 3px; background: var(--blue); margin: 12px auto 0; }

/* ------------------------------ Marquee -------------------------------- */
.marquee { overflow: hidden; padding: 24px 0; border-top: 1px solid var(--hairline); border-bottom: 1px solid var(--hairline);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); mask-image: linear-gradient(90deg, transparent, #000 6%, #000 94%, transparent); }
.marquee__track { display: flex; gap: 56px; width: max-content; animation: marquee 48s linear infinite; }
.marquee:hover .marquee__track { animation-play-state: paused; }
.marquee__track span { font-family: var(--font-head); font-weight: 600; font-size: .95rem; letter-spacing: .08em; text-transform: uppercase; color: var(--text-soft); white-space: nowrap; }
@keyframes marquee { to { transform: translateX(-50%); } }

/* ------------------------------ Dark CTA band -------------------------- */
.cta-dark { background: linear-gradient(140deg, var(--blue-deep), var(--dark) 70%); color: #cfe0f0; text-align: center; }
.cta-dark h2 { color: #fff; max-width: 24ch; margin-inline: auto; }
.cta-dark p { max-width: 52ch; margin: 0 auto 28px; }
.cta-dark .hero__actions { margin-top: 0; }
.cta-dark .cta-phone { margin-top: 22px; font-family: var(--font-head); font-size: .95rem; color: #9fc0dd; }
.cta-dark .cta-phone a { color: #fff; font-weight: 600; }
.cta-dark .cta-phone a:hover { color: var(--blue-soft); }

/* ------------------------------ Contact -------------------------------- */
.contact-grid { display: grid; gap: clamp(36px, 5vw, 70px); }
@media (min-width: 940px) { .contact-grid { grid-template-columns: 1fr 1.15fr; } }
.contact-list { border-top: 1px solid var(--hairline); }
.contact-list > div { display: grid; grid-template-columns: 120px 1fr; gap: 18px; padding: 20px 0; border-bottom: 1px solid var(--hairline); }
.contact-list h3 { font-size: .78rem; letter-spacing: .14em; text-transform: uppercase; color: var(--text-soft); font-weight: 600; margin: 5px 0 0; }
.contact-list a { color: var(--blue); font-family: var(--font-head); font-weight: 600; }
.contact-list a:hover { color: var(--blue-deep); }
.contact-list p { margin: 0; }
.contact-list .sub { font-size: .84rem; color: var(--text-soft); margin-top: 2px; }

.form { border: 1px solid var(--hairline); background: #fff; border-radius: var(--r); padding: clamp(26px, 4vw, 42px); box-shadow: var(--shadow); }
.field { margin-bottom: 18px; }
.field label { display: block; font-family: var(--font-head); font-weight: 600; font-size: .88rem; color: var(--navy); margin-bottom: 7px; }
.field input, .field select, .field textarea {
  width: 100%; font: inherit; font-size: .98rem; color: var(--navy); padding: 13px 15px;
  border: 1px solid var(--hairline); border-radius: var(--r); background: var(--paper);
  transition: border-color .2s, background .2s, box-shadow .2s;
}
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--blue); background: #fff; box-shadow: 0 0 0 4px rgba(14, 90, 167, .12); }
.field textarea { min-height: 140px; resize: vertical; }
.form__row { display: grid; gap: 18px; }
@media (min-width: 560px) { .form__row { grid-template-columns: 1fr 1fr; } }
.form__note { font-size: .84rem; color: var(--text-soft); margin: 12px 0 0; }
.form-status { margin-top: 14px; font-size: .92rem; font-family: var(--font-head); }
.form-status.ok { color: #0e7a4f; } .form-status.err { color: #b3372a; }

/* ------------------------------ Footer --------------------------------- */
.site-footer { background: var(--dark); color: #8ba4bd; padding: clamp(56px, 7vw, 84px) 0 32px; }
.footer-grid { display: grid; gap: 38px; grid-template-columns: 1fr; }
@media (min-width: 780px) { .footer-grid { grid-template-columns: 1.6fr 1fr 1fr 1.3fr; } }
.site-footer h4 { color: #fff; font-size: .74rem; letter-spacing: .18em; text-transform: uppercase; margin-bottom: 18px; font-weight: 600; }
.site-footer a { color: #8ba4bd; transition: color .2s; }
.site-footer a:hover { color: #fff; }
.footer-links { list-style: none; display: grid; gap: 11px; font-size: .94rem; }
.footer-about { max-width: 36ch; font-size: .94rem; line-height: 1.75; }
.footer-brand { display: flex; align-items: center; margin-bottom: 20px; }
.footer-bottom { display: flex; flex-wrap: wrap; gap: 12px 24px; justify-content: space-between; align-items: center;
  margin-top: 50px; padding-top: 24px; border-top: 1px solid var(--hairline-dark); font-size: .82rem; color: #64809d; }

/* ------------------------------ Reveal --------------------------------- */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity .7s var(--ease), transform .7s var(--ease); }
.reveal.is-visible { opacity: 1; transform: none; }
.reveal[data-delay="1"] { transition-delay: .08s; }
.reveal[data-delay="2"] { transition-delay: .16s; }
.reveal[data-delay="3"] { transition-delay: .24s; }

/* ------------------------------ Misc ----------------------------------- */
.skip-link { position: absolute; left: -999px; top: 0; background: var(--blue); color: #fff; padding: 10px 16px; z-index: 200; }
.skip-link:focus { left: 0; }
:focus-visible { outline: 3px solid rgba(14, 90, 167, .5); outline-offset: 2px; }
.float-actions { position: fixed; right: 18px; bottom: 18px; z-index: 90; }
.float-actions a {
  width: 52px; height: 52px; border-radius: 50%; display: grid; place-items: center;
  background: var(--blue); box-shadow: 0 10px 26px rgba(14, 90, 167, .4);
  transition: background .25s var(--ease), transform .25s var(--ease);
}
.float-actions a:hover { background: var(--blue-deep); transform: scale(1.07); }
.float-actions svg { width: 24px; height: 24px; }