:root{--ink:#06121d;--navy:#061b2d;--blue:#073d61;--cyan:#37d7ff;--lime:#c9ff3f;--paper:#f4f7f5;--white:#fff;--muted:#a8bac5;--line:rgba(255,255,255,.16)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--ink);color:var(--white);font-family:"DM Sans",sans-serif;font-size:16px;line-height:1.55}a{color:inherit;text-decoration:none}h1,h2,h3,.brand{font-family:"Space Grotesk",sans-serif}h1,h2,h3,p{margin-top:0}.skip{position:fixed;left:1rem;top:-5rem;background:var(--lime);color:var(--ink);padding:.8rem 1rem;z-index:100}.skip:focus{top:1rem}.site-header{height:84px;display:flex;align-items:center;justify-content:space-between;padding:0 4vw;background:rgba(4,19,32,.9);backdrop-filter:blur(14px);position:absolute;z-index:10;width:100%;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:.7rem;font-weight:700;letter-spacing:.13em}.brand small{font-size:.55em;color:var(--cyan)}.brand-mark{width:42px;height:42px;border:1px solid rgba(255,255,255,.4);border-radius:50%;display:grid;place-items:center;letter-spacing:0}.brand-mark span{font-size:.45em;color:var(--lime);vertical-align:top}.site-header nav{display:flex;gap:2rem;align-items:center}.site-header nav>a:not(.button){font-size:.9rem;color:#dce8ee}.button{display:inline-flex;align-items:center;justify-content:center;background:var(--lime);color:var(--ink);padding:1rem 1.4rem;border-radius:2px;border:0;font:700 .9rem "DM Sans";text-transform:uppercase;letter-spacing:.08em;cursor:pointer}.button-small{padding:.65rem 1rem}.menu-button{display:none}.hero{height:min(900px,100vh);min-height:700px;position:relative;display:flex;align-items:center;overflow:hidden}.hero>img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover}.hero-shade{position:absolute;inset:0;background:linear-gradient(90deg,rgba(1,14,27,.95) 0%,rgba(2,19,34,.78) 37%,rgba(2,17,29,.12) 72%),linear-gradient(0deg,rgba(2,15,25,.7),transparent 45%)}.hero-content{position:relative;z-index:1;max-width:750px;margin-left:8vw;padding-top:60px}.eyebrow{font-size:.78rem;font-weight:700;text-transform:uppercase;letter-spacing:.18em;color:var(--lime);margin-bottom:1.2rem}.eyebrow.dark{color:#167b9c}.hero h1{font-size:clamp(4rem,7.7vw,8rem);line-height:.86;letter-spacing:-.065em;margin-bottom:2rem}.hero h1 em{font-style:normal;color:var(--cyan)}.hero-copy{max-width:600px;font-size:1.18rem;color:#d2e2ea}.hero-actions{display:flex;align-items:center;gap:2rem;margin-top:2rem}.text-link{font-weight:700}.text-link span{color:var(--cyan);margin-left:.35rem}.dive-note{position:absolute;right:5vw;bottom:5vw;z-index:2;border-left:3px solid var(--lime);padding:.5rem 1rem;display:grid;background:rgba(3,18,30,.45);backdrop-filter:blur(8px)}.dive-note span{font:700 1.5rem "Space Grotesk";color:var(--lime)}.dive-note small{color:var(--muted)}.ticker{white-space:nowrap;overflow:hidden;background:var(--lime);color:var(--ink);padding:.8rem;display:flex;justify-content:space-around;font-size:.78rem;font-weight:700;letter-spacing:.12em}.ticker i{width:5px;height:5px;background:#167b9c;border-radius:50%;align-self:center}.section{padding:8rem 8vw}.intro{background:var(--paper);color:var(--ink);display:grid;grid-template-columns:1fr 1fr;gap:8vw}.intro h2,.section-heading h2,.about h2,.contact h2,.glossary h2{font-size:clamp(2.8rem,5vw,5rem);line-height:.98;letter-spacing:-.05em}.intro h2 span{color:#168bac}.intro-copy{font-size:1.15rem;max-width:640px;padding-top:2.6rem}.intro-copy p{color:#324653}.dark-link{color:var(--ink);display:inline-block;margin-top:1rem}.essentials{display:grid;grid-template-columns:repeat(4,1fr);background:#e8efed;color:var(--ink);padding:0 8vw 7rem;gap:1px}.essentials article{padding:2rem;border-top:3px solid #b8c9ca}.essentials article:hover{border-color:#168bac}.essentials b{font-family:"Space Grotesk";color:#168bac}.essentials h3{font-size:1.6rem;margin:1.8rem 0 .6rem}.essentials p{color:#52656e}.training{background:var(--navy)}.section-heading{display:grid;grid-template-columns:1fr 1.2fr .8fr;gap:4vw;align-items:end;margin-bottom:4rem}.section-heading .eyebrow{align-self:start}.section-heading h2{margin:0}.section-heading>p:last-child{color:var(--muted)}.course-grid{display:grid;grid-template-columns:1.3fr 1fr;gap:1.5rem}.course{background:#0c2c45;padding:3rem;min-height:510px;display:flex;flex-direction:column;border-top:4px solid var(--cyan)}.course.featured{background:var(--cyan);color:var(--ink);border-color:var(--lime)}.course>div{display:flex;justify-content:space-between}.tag{font-size:.75rem;font-weight:700;text-transform:uppercase;letter-spacing:.14em}.course-num{font:700 2rem "Space Grotesk";opacity:.35}.course h3{font-size:2.8rem;margin:4rem 0 1rem}.course p{max-width:550px}.course ul{padding-left:1.2rem;margin-bottom:2rem}.course a{margin-top:auto;font-weight:700}.knowledge{background:var(--paper);color:var(--ink);padding:8rem 8vw}.section-heading.compact{grid-template-columns:.5fr 1fr}.resource-list{border-top:1px solid #afc1c5}.resource-list details{border-bottom:1px solid #afc1c5}.resource-list summary{display:grid;grid-template-columns:60px 1fr auto;gap:1rem;padding:1.7rem 0;cursor:pointer;font:600 clamp(1.15rem,2vw,1.55rem) "Space Grotesk";list-style:none}.resource-list summary span{color:#168bac;font-size:.8rem}.resource-list summary b{color:#168bac}.resource-list details[open] summary b{transform:rotate(45deg)}.resource-list details p{max-width:820px;color:#435862;margin:0 0 2rem 76px}.library-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem;margin-top:4rem}.library-cards article{background:#fff;padding:2rem;border-top:3px solid #168bac}.library-cards span{font-size:.7rem;font-weight:700;letter-spacing:.14em;color:#168bac}.library-cards h3{font-size:1.7rem;margin:2rem 0 .6rem}.library-cards p{color:#5a6b73}.library-cards a{font-weight:700}.glossary{display:grid;grid-template-columns:1fr 1.2fr;gap:8vw;background:#05243a}.glossary dl{margin:0}.glossary dl div{display:grid;grid-template-columns:100px 1fr;border-bottom:1px solid var(--line);padding:1.2rem 0}.glossary dt{color:var(--lime);font:700 1.2rem "Space Grotesk"}.glossary dd{margin:0;color:#d4e4ea}.about{background:#e8efed;color:var(--ink)}.about-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:8vw}.about-grid div{font-size:1.12rem;color:#40535d;padding-top:1rem}.contact{display:grid;grid-template-columns:1fr 1fr;gap:8vw;padding:8rem;background:#08799a}.contact .eyebrow{color:var(--lime)}.contact form{background:#fff;color:var(--ink);padding:2.5rem;display:grid;gap:1.3rem}.contact label{display:grid;gap:.45rem;font-size:.78rem;font-weight:700;text-transform:uppercase;letter-spacing:.08em}.contact input,.contact select{border:0;border-bottom:1px solid #a8b6bb;padding:.85rem 0;font:1rem "DM Sans";background:transparent;border-radius:0}.contact input:focus,.contact select:focus{outline:2px solid #08799a;outline-offset:3px}.form-note{font-size:.8rem;color:#60717a;margin:0}.form-note.success{color:#08799a;font-weight:700}footer{padding:4rem 8vw;background:#03101b;display:grid;grid-template-columns:1fr 1.5fr 1fr;gap:3rem;align-items:start;color:#9eb1bd}footer .brand{color:#fff}footer div{display:grid;gap:.5rem}footer small{grid-column:1/-1;border-top:1px solid var(--line);padding-top:1.5rem}.menu-button{background:transparent;color:#fff;border:1px solid var(--line);padding:.6rem .8rem}
@media(max-width:900px){.site-header{height:72px}.menu-button{display:block}.site-header nav{display:none;position:absolute;top:72px;left:0;right:0;background:#041320;padding:2rem;flex-direction:column;align-items:flex-start}.site-header nav.open{display:flex}.hero{min-height:760px}.hero-content{margin:0 6vw;padding-right:6vw}.hero h1{font-size:clamp(3.7rem,16vw,6rem)}.dive-note{left:6vw;right:auto}.intro,.glossary,.about-grid,.contact{grid-template-columns:1fr}.section{padding:6rem 6vw}.essentials{grid-template-columns:1fr 1fr;padding:0 6vw 5rem}.section-heading{grid-template-columns:1fr}.course-grid{grid-template-columns:1fr}.library-cards{grid-template-columns:1fr}.contact{padding:6rem 6vw}.knowledge{padding:6rem 6vw}footer{grid-template-columns:1fr 1fr}footer p{grid-column:1/-1}}
@media(max-width:560px){.hero-actions{align-items:flex-start;flex-direction:column;gap:1rem}.hero-shade{background:linear-gradient(90deg,rgba(1,14,27,.94),rgba(2,19,34,.5)),linear-gradient(0deg,rgba(2,15,25,.8),transparent)}.dive-note{bottom:2rem}.ticker{justify-content:flex-start;gap:2rem}.essentials{grid-template-columns:1fr}.course{padding:2rem;min-height:470px}.resource-list summary{grid-template-columns:40px 1fr auto}.resource-list details p{margin-left:56px}.contact form{padding:1.5rem}footer{grid-template-columns:1fr}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}

.contact-card{background:#fff;color:var(--ink);padding:2.5rem;align-self:start}
.contact-card h3{font-size:2rem;margin-bottom:1.5rem}
.contact-card .button{margin-bottom:1rem}
.contact-card a:not(.button){color:#08799a;font-weight:700}
.admin-bar .site-header{top:32px}
@media(max-width:782px){.admin-bar .site-header{top:46px}}

.glossary-nav{display:flex;flex-wrap:wrap;gap:.45rem;margin:2rem 0 3rem}
.glossary-nav a{width:2.55rem;height:2.55rem;display:grid;place-items:center;background:#fff;border:1px solid #afc1c5;color:#06243a;font:700 .85rem "Space Grotesk";transition:.2s ease}
.glossary-nav a:hover,.glossary-nav a:focus{background:#c9ff3f;border-color:#c9ff3f;transform:translateY(-2px)}
.glossary-intro{max-width:850px;color:#435862;font-size:1.05rem}
.glossary-group{width:100%;margin:4rem 0;padding:0}
.glossary-group h2{width:100%;margin:0 0 1.5rem;font-size:clamp(2rem,4vw,3.5rem)}
.glossary-group dl{margin:0;border-top:1px solid #afc1c5}
.glossary-group dl div{display:grid;grid-template-columns:minmax(180px,240px) minmax(0,1fr);gap:2rem;padding:1.35rem 0;border-bottom:1px solid #c8d4d6}
.glossary-group dt{font:700 1.08rem "Space Grotesk";color:#073d61}
.glossary-group dd{margin:0;color:#435862}
.nitrox-terms{background:#06243a;color:#fff;padding:clamp(1.5rem,3vw,2.5rem);border-radius:3px}
.nitrox-terms h2,.nitrox-terms dt{color:#c9ff3f}
.nitrox-terms dd{color:#d4e4ea}
.nitrox-terms dl,.nitrox-terms dl div{border-color:rgba(255,255,255,.18)}
@media(max-width:650px){.glossary-group dl div{grid-template-columns:1fr;gap:.45rem}.glossary-nav a{width:2.35rem;height:2.35rem}}

.page-with-ads{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:clamp(2rem,5vw,5rem);align-items:start}
.page-primary{min-width:0}
.page-primary>h1{font-size:clamp(2.8rem,5vw,5rem);line-height:1;letter-spacing:-.04em;margin-bottom:3rem}
.page-ad-sidebar{display:grid;gap:2rem;position:sticky;top:2rem}
.ad-position{width:300px;max-width:100%}
.ad-disclosure{display:block;margin-bottom:.35rem;color:#60717a;font-size:.66rem;font-weight:700;letter-spacing:.12em;text-transform:uppercase}
.ad-position a{display:block;line-height:0;border:1px solid #b7c5ca;background:#061b2d;box-shadow:0 8px 24px rgba(6,27,45,.12);transition:transform .2s ease,box-shadow .2s ease}
.ad-position a:hover,.ad-position a:focus{transform:translateY(-3px);box-shadow:0 12px 30px rgba(6,27,45,.2);outline:3px solid #168bac;outline-offset:3px}
.ad-position img{display:block;width:100%;height:auto;aspect-ratio:6/5;object-fit:cover}
@media(max-width:1050px){.page-with-ads{grid-template-columns:minmax(0,1fr) 260px}.ad-position{width:260px}}
@media(max-width:800px){.page-with-ads{grid-template-columns:1fr}.page-ad-sidebar{position:static;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem}.ad-position{width:100%}}
@media(max-width:650px){.page-ad-sidebar{grid-template-columns:1fr}.ad-position{width:300px;max-width:100%;margin-inline:auto}}

.home-glossary-content{display:flex;flex-direction:column;gap:2rem}
.home-glossary-content dl{width:100%}
.glossary-button{align-self:flex-start}

.brand-logo-shell{display:flex;background:transparent;padding:0;line-height:0}
.nitrox-logo{display:block;width:245px;height:auto}
.footer-logo{width:max-content}
@media(max-width:560px){.nitrox-logo{width:190px}.site-header{padding-left:3vw;padding-right:3vw}}