:root{--ink:#102e35;--paper:#f4f0e8;--cream:#fbf8f1;--teal:#0d7774;--mint:#bde4d8;--amber:#e9a442;--coral:#db6d54;--line:#cbd0ca}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Arial,Helvetica,sans-serif}button,a,select{font:inherit}.topbar{height:76px;padding:0 5vw;display:flex;align-items:center;justify-content:space-between;background:var(--cream)}.brand{display:flex;align-items:center;gap:10px;color:inherit;text-decoration:none;font-size:20px}.brand b>span{color:var(--teal)}.mark{display:grid;place-items:center;width:34px;height:34px;background:var(--ink);color:#fff;border-radius:6px;font-family:Georgia,serif;font-style:italic}.course{font-size:11px;letter-spacing:2px;font-weight:800}.saved{font-size:11px;color:#567068;background:#e8ede8;padding:9px 13px;border-radius:20px}.progress{height:4px;background:#d9ddd6;position:sticky;top:0;z-index:10}.progress i{display:block;height:100%;width:33%;background:var(--amber);transition:.3s}.hero{height:660px;position:relative;overflow:hidden}.hero>img{width:100%;height:100%;object-fit:cover}.shade{position:absolute;inset:0;background:linear-gradient(90deg,rgba(9,29,34,.9),rgba(9,29,34,.68) 38%,rgba(9,29,34,.05) 72%)}.hero-copy{position:absolute;left:7vw;top:13%;width:min(590px,48vw);color:#fff}.eyebrow,.kicker{font-size:11px;font-weight:900;letter-spacing:2.3px}.eyebrow{display:inline-block;background:var(--amber);color:var(--ink);padding:7px 11px}.hero h1,h2,h3{font-family:Georgia,serif}.hero h1{font-size:clamp(48px,6vw,82px);line-height:.94;margin:25px 0 20px;letter-spacing:-3px}.hero h1 em{color:#ffd68e;font-weight:400}.hero-copy p{font-size:18px;line-height:1.6;max-width:520px;color:#e4ece8}.primary{border:0;border-radius:3px;background:var(--amber);color:var(--ink);font-weight:900;padding:15px 19px;text-decoration:none;display:inline-flex;gap:20px;cursor:pointer;box-shadow:5px 5px 0 rgba(9,31,35,.18)}.primary:disabled{opacity:.45}.mission{position:absolute;right:5vw;bottom:35px;width:280px;color:#fff;border-left:3px solid var(--amber);padding:7px 0 7px 18px;display:flex;flex-direction:column;gap:8px}.mission b{font-size:10px;letter-spacing:2px}.mission span{font-family:Georgia,serif;font-size:18px}.lesson-nav{background:#0f343a;display:flex;padding:0 7vw;position:sticky;top:4px;z-index:9}.lesson-nav button{flex:1;max-width:270px;display:flex;gap:14px;align-items:center;background:transparent;color:#a9c0bd;border:0;border-bottom:4px solid transparent;padding:20px;cursor:pointer;text-align:left}.lesson-nav button>b{font-family:Georgia,serif;font-size:24px;font-weight:400}.lesson-nav button span{display:flex;flex-direction:column}.lesson-nav strong{color:#fff}.lesson-nav small{font-size:11px}.lesson-nav .active{background:#18444a;border-color:var(--amber)}.section{display:none}.active-section{display:block}.grid,.heading,.layers,.panel-wrap{max-width:1180px;margin:auto}.intro{display:grid;grid-template-columns:1.35fr .8fr;gap:90px;padding:100px 35px}.kicker{color:var(--teal)}h2{font-size:clamp(38px,4vw,58px);line-height:1.04;letter-spacing:-1.5px;margin:15px 0 25px}h2 em{color:var(--teal);font-weight:400}.lead{font-size:20px;line-height:1.65}.intro p{line-height:1.7;color:#435c60}.definition{background:var(--ink);color:#fff;padding:38px;align-self:center;box-shadow:12px 12px 0 var(--mint);transform:rotate(1deg)}.definition>span,.layer-grid article>span{font-size:10px;letter-spacing:2px;font-weight:900;color:#85d1c5}.definition p{font-family:Georgia,serif;color:#fff;font-size:24px;line-height:1.4}.definition small{display:block;border-top:1px solid #49636a;padding-top:18px;color:#c6d5d2;line-height:1.5}.model{background:#e8e2d7;padding:90px max(5vw,30px)}.heading{display:flex;justify-content:space-between;align-items:end;margin-bottom:35px}.heading h2{margin-bottom:0}.heading>p{max-width:390px;line-height:1.6;color:#51666a}.functions{display:grid;grid-template-columns:repeat(4,1fr);max-width:1180px;margin:auto}.functions article{min-height:305px;padding:25px}.functions article>span{font-family:Georgia,serif;font-size:42px;color:rgba(16,46,53,.35)}.functions small{display:block;font-weight:900;letter-spacing:2px;margin-top:30px}.functions h3,.layer-grid h3{font-size:34px;margin:5px 0}.functions p{line-height:1.5;min-height:50px}.functions article>b{display:block;font-size:12px;border-top:1px solid rgba(16,46,53,.2);padding-top:18px}.f0{background:var(--mint)}.f1{background:#f3c76d}.f2{background:#b8d5dc}.f3{background:#eba18e}.think{max-width:1180px;margin:25px auto 0;border:1px dashed #81918d;padding:22px;display:grid;grid-template-columns:auto 1fr auto;gap:20px;align-items:center}.think>b{font-size:10px;letter-spacing:1.5px}.think button,.link{border:0;background:transparent;color:var(--teal);font-weight:900;text-decoration:underline;cursor:pointer}.think p{grid-column:2/4;margin:0}.devices{padding:100px 35px;display:grid;grid-template-columns:1.35fr .9fr;gap:65px;align-items:center}.photo{position:relative;min-height:500px;box-shadow:14px 14px 0 #d8cdbb}.photo>img{position:absolute;width:100%;height:100%;object-fit:cover}.photo>div{position:absolute;left:-18px;bottom:22px;background:var(--cream);padding:18px 24px;display:flex;gap:15px;align-items:center}.photo>div>b{font-family:Georgia,serif;font-size:34px;color:var(--amber)}.accordion{border-top:1px solid var(--line)}.accordion button{display:grid;grid-template-columns:1fr auto;width:100%;padding:16px 2px;background:transparent;border:0;border-bottom:1px solid var(--line);text-align:left;cursor:pointer}.accordion button>span{font-family:Georgia,serif;font-size:21px}.accordion button>i{font-style:normal;font-size:22px;color:var(--teal)}.accordion p{grid-column:1/3;margin:12px 0 4px;line-height:1.55;color:#51666a}.accordion .open{background:#e7ede8;padding-left:12px;padding-right:12px}.layers{padding:80px 35px 100px}.layer-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.layer-grid article{background:#fff;padding:32px;border-top:5px solid var(--teal);box-shadow:0 7px 25px rgba(28,45,45,.07)}.layer-grid article>span{color:var(--teal)}.layer-grid p,.layer-grid li{line-height:1.6;color:#4c6265}.layer-grid li{margin:12px 0}.layer-grid .firmware{background:var(--ink);color:#fff;border-color:var(--amber)}.layer-grid .firmware p{color:#d6e2df}.chips{display:flex;flex-wrap:wrap;gap:6px}.chips b{font-size:10px;background:#e5eeeb;color:var(--teal);padding:7px}.warning{border:1px solid #547177;padding:15px;font-size:12px;line-height:1.5}.warning b{display:block;color:var(--amber)}.ready{background:var(--teal);color:#fff;padding:55px max(7vw,35px);display:flex;justify-content:space-between;align-items:center}.ready h2{font-size:42px;margin:10px 0}.ready .kicker{color:#f7cd76}.panel-wrap{padding:85px 35px 110px}.center{text-align:center;max-width:780px;margin:0 auto 45px}.center p,.exam-head p{color:#52686b;line-height:1.6;font-size:17px}.sim-progress{max-width:880px;margin:0 auto 20px;font-size:12px}.sim-progress div{height:6px;background:#d4dbd5;margin:10px 0}.sim-progress i{display:block;height:100%;background:var(--teal)}.ticket{max-width:880px;margin:auto;background:#fff;display:grid;grid-template-columns:220px 1fr;box-shadow:12px 12px 0 #d9d1c3}.ticket aside{background:var(--ink);color:#fff;padding:35px;display:flex;flex-direction:column}.ticket aside span,.ticket-main>small{font-size:10px;letter-spacing:2px;font-weight:900;color:#81c9be}.ticket aside strong{font-family:Georgia,serif;font-size:34px;margin:20px 0}.ticket-main{padding:45px}.ticket-main h3{font-size:31px;line-height:1.3;margin:12px 0 30px}.ticket-main label{display:block;font-size:10px;font-weight:900;letter-spacing:1.5px;margin-bottom:7px}.ticket-main select{width:100%;padding:14px;border:1px solid #aebbb7;background:#fbfaf6;margin-bottom:22px}.feedback{max-width:880px;margin:25px auto;padding:20px}.feedback.good{background:#d8ede4}.feedback.bad{background:#f4d8d1}.complete{max-width:880px;margin:auto;background:var(--ink);color:#fff;text-align:center;padding:55px}.complete h3{font-size:72px;margin:15px}.tips{max-width:880px;margin:70px auto 0}.tips>div{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.tips span{border-top:3px solid var(--amber);padding:14px;background:#ebe6dd;font-size:13px}.tips b{display:block;margin-bottom:5px}.exam-head{display:grid;grid-template-columns:1fr 160px;gap:30px;align-items:center}.exam-head aside{background:var(--amber);padding:25px;text-align:center;display:flex;flex-direction:column}.exam-head aside b{font-family:Georgia,serif;font-size:52px}.rules{display:flex;gap:30px;padding:17px 20px;background:#dfe9e5;font-size:12px;margin:30px 0}.question{display:grid;grid-template-columns:120px 1fr;border-top:1px solid var(--line);padding:35px 0}.qmeta{display:flex;flex-direction:column;gap:8px}.qmeta>b{font-family:Georgia,serif;font-size:36px;color:#9aa9a5}.qmeta span,.qmeta small{font-size:9px;letter-spacing:1px;font-weight:900}.qbody h3{font-size:23px;line-height:1.4;margin:0 0 20px}.options{display:grid;grid-template-columns:1fr 1fr;gap:9px}.options label{border:1px solid #bdc7c3;background:#fff;padding:13px;display:flex;align-items:center;gap:12px;cursor:pointer}.options label>b{display:grid;place-items:center;width:27px;height:27px;border:1px solid #aab7b2;border-radius:50%;font-size:11px}.options input:checked~b{background:var(--teal);color:#fff}.answer-key{box-shadow:inset 4px 0 #4f9e79}.rationale{margin-top:15px;background:#e5ebe7;padding:15px;display:flex;gap:18px;line-height:1.5}.submit{position:sticky;bottom:0;background:var(--ink);color:#fff;padding:18px 25px;display:flex;align-items:center;justify-content:space-between}.score{background:var(--teal);color:#fff;padding:45px;display:grid;grid-template-columns:150px 1fr auto;gap:35px;align-items:center}.score>strong{width:130px;height:130px;border:8px solid #f6cf7b;border-radius:50%;display:grid;place-content:center;text-align:center;font-family:Georgia,serif;font-size:33px}footer{background:#0a292e;color:#fff;padding:30px 5vw;display:flex;align-items:center;justify-content:space-between}footer p,footer>span{font-size:12px;color:#adc3c0}@media(max-width:900px){.saved{display:none}.hero-copy{width:76vw}.intro,.devices{grid-template-columns:1fr;gap:45px}.functions{grid-template-columns:1fr 1fr}.layer-grid{grid-template-columns:1fr}.tips>div{grid-template-columns:1fr 1fr}}@media(max-width:620px){.topbar{padding:0 18px}.course{font-size:8px}.hero{height:570px}.hero-copy{left:24px;top:10%;width:88vw}.hero h1{font-size:49px}.mission{display:none}.lesson-nav{padding:0}.lesson-nav button{padding:13px 8px}.lesson-nav small{display:none}.intro,.devices,.layers,.panel-wrap{padding:65px 20px}.heading{display:block}.functions{grid-template-columns:1fr}.think{grid-template-columns:1fr}.think p{grid-column:auto}.photo{min-height:310px}.ready{display:block}.ticket{grid-template-columns:1fr}.ticket-main{padding:28px}.tips>div,.options{grid-template-columns:1fr}.exam-head{grid-template-columns:1fr}.exam-head aside{display:none}.rules{flex-direction:column}.question{grid-template-columns:1fr}.qmeta{flex-direction:row;align-items:center;margin-bottom:15px}.score{grid-template-columns:1fr;text-align:center}.score>strong{margin:auto}footer{flex-direction:column;gap:14px;text-align:center}}