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.glossary-section{background:#0c1a2a;border-top:1px solid var(--line);padding:102px 0 120px}.glossary-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin-top:28px}.glossary-card{padding:19px 21px;background:#0a1726;border:1px solid var(--line);border-radius:5px;min-height:130px}.glossary-card h3{font-size:15px;margin:0 0 6px}.glossary-card h3 span{font-weight:400;font-family:var(--serif);font-size:11px;color:var(--gold)}.glossary-card p{font-size:12px;color:#9bafbe;line-height:1.8;margin:0}
.final-banner{border:1px solid #4f5365;border-radius:10px;min-height:352px;overflow:hidden;margin-top:90px;margin-bottom:100px;display:flex;align-items:center;background:#101f31}.final-art{position:absolute;inset:0;background:url('assets/explore-hero.webp') center/cover;opacity:.63}.final-art:after{content:'';position:absolute;inset:0;background:linear-gradient(90deg,#0c1827 5%,rgba(9,19,31,.92) 39%,rgba(9,19,31,.11))}.final-content{position:relative;padding:46px 58px}.final-content h2{font-size:clamp(27px,3.3vw,42px);line-height:1.4;letter-spacing:-.06em;margin:15px 0}.final-content p{font-size:13px;color:#aec1ce;margin-bottom:24px}.footer{background:#06101a;border-top:1px solid var(--line);padding:58px 0 25px}.footer-main{display:flex;justify-content:space-between;gap:30px}.footer-logo{font-family:var(--serif);font-size:21px;letter-spacing:.12em}.footer-logo span,.footer-logo small{color:var(--gold)}.footer-main p{font-size:12px;color:#8295a5;line-height:1.9}.footer-links{display:flex;flex-wrap:wrap;align-content:start;gap:19px;font-size:12px;color:#adbdc8}.footer-links a:hover{color:var(--gold)}.footer-bottom{border-top:1px solid var(--line);margin-top:45px;padding-top:17px;display:flex;justify-content:space-between;gap:20px;font-size:10px;color:#728799}
.lesson-dialog{border:1px solid #385367;background:#0c1c2d;color:var(--ink);width:min(730px,calc(100% - 20px));max-height:min(88vh,900px);border-radius:10px;padding:0;box-shadow:0 40px 140px #000a}.lesson-dialog::backdrop{background:rgba(0,9,18,.8);backdrop-filter:blur(7px)}.dialog-inner{max-height:min(88vh,900px);overflow:auto;overscroll-behavior:contain}.dialog-header{display:flex;align-items:center;justify-content:space-between;padding:15px 29px;position:sticky;top:0;background:#112539;z-index:2;border-bottom:1px solid var(--line);color:var(--gold);font-size:10px;letter-spacing:.15em}.dialog-close{width:33px;height:33px;border:1px solid rgba(199,215,230,.3);border-radius:50%;background:none;color:#d5e1e9;font-size:24px;line-height:1}.lesson-content{padding:36px 35px 39px}.lesson-content h2{font-size:33px;letter-spacing:-.06em;margin:10px 0 0}.lesson-content .subheading{font-size:14px;color:var(--gold);margin:0 0 25px}.lesson-content .lead{font-size:16px;line-height:1.95;color:#d0dde5}.lesson-content h3{font-size:15px;margin:27px 0 10px;display:flex;align-items:center;gap:10px}.lesson-content h3:before{content:'';width:5px;height:17px;background:var(--gold);border-radius:2px}.lesson-content ul{padding-left:21px;color:#b0c3d0;font-size:13px;line-height:2}.lesson-content li{padding-left:3px;margin:4px 0}.lesson-content .lesson-note{border-left:2px solid #68d7bf;background:rgba(36,109,103,.12);padding:13px 17px;margin-top:16px;color:#c4e7de;font-size:13px;line-height:1.9}.lesson-content .lesson-caution{border-left-color:#e9b07a;background:rgba(125,84,49,.13);color:#e1c5ae}.lesson-content .formula{background:#071624;border:1px solid #294357;padding:18px;border-radius:5px;font-size:14px;color:#f0d5aa;font-variant-numeric:tabular-nums;line-height:1.9}.lesson-content .practice{background:#102b38;padding:20px;border-radius:5px;border:1px solid rgba(92,215,190,.23);font-size:13px;color:#c8e2df;line-height:1.9}.lesson-check{background:#102237;border:1px solid var(--line);padding:20px;margin-top:22px;border-radius:6px}.lesson-check h4{margin:0 0 13px;font-size:14px}.lesson-check .quiz-option{width:100%;margin-top:7px}.lesson-check-result{font-size:12px;margin-top:11px;color:var(--gold);line-height:1.8}.lesson-footer{border-top:1px solid var(--line);margin-top:30px;padding-top:20px;display:flex;align-items:center;justify-content:space-between;gap:10px}.lesson-footer .btn{padding:10px 15px;font-size:11px;min-height:41px}.lesson-footer small{color:#899dab;font-size:11px}.back-top{position:fixed;bottom:25px;right:25px;z-index:15;width:43px;height:43px;border:1px solid #536d7b;border-radius:50%;background:#0c2736;color:var(--gold);font-size:19px;box-shadow:0 5px 23px #0008;opacity:0;pointer-events:none;transition:opacity .2s}.back-top.visible{opacity:1;pointer-events:all}
@media(max-width:1100px){.top-nav{gap:13px}.top-nav a{font-size:11px}.brand-type b{font-size:14px}.brand-type small{font-size:7px}.header-cta{display:none}.intro-grid{gap:25px}.patterns-grid{grid-template-columns:repeat(3,1fr)}.challenge-layout{gap:35px}}
@media(max-width:800px){.container{width:calc(100% - 36px)}.site-header{padding:0 20px;height:70px}.top-nav{display:none}.menu-button{display:flex;margin-left:auto}.mobile-nav{top:70px}.hero{min-height:695px}.hero-art{background-position:60% center}.hero-gradient{background:linear-gradient(90deg,rgba(4,12,25,.96),rgba(5,15,27,.7) 65%,rgba(7,17,30,.18)),linear-gradient(0deg,#081421,transparent 29%)}.hero h1{font-size:clamp(35px,7vw,56px)}.hero p{font-size:14px}.intro{padding:85px 0}.intro-grid{grid-template-columns:1fr}.stats-grid{max-width:480px}.feature-grid{grid-template-columns:1fr 1fr}.feature-card:last-child{grid-column:1/-1;min-height:190px}.curriculum-section,.laboratory-section,.patterns-section,.challenge-section,.glossary-section{padding:75px 0}.section-row{align-items:start;flex-direction:column;gap:12px}.progress-box{width:100%;max-width:420px}.lessons-grid,.glossary-grid{grid-template-columns:repeat(2,1fr)}.patterns-grid{grid-template-columns:repeat(2,1fr)}.challenge-layout{grid-template-columns:1fr}.challenge-art{height:180px;margin-top:25px}.quiz-card{min-height:0}.section-heading{font-size:36px}.final-banner{margin-top:65px;margin-bottom:70px}.final-content{padding:35px}.footer-main{flex-direction:column}}
@media(max-width:530px){.container{width:calc(100% - 28px)}.site-header{padding:0 15px}.brand-mark{width:36px;height:36px}.brand-type b{font-size:13px}.brand-type small{font-size:6.5px}.hero{min-height:640px}.hero-inner{padding-top:90px}.hero h1{font-size:38px;margin:25px 0 15px}.hero p{font-size:13px}.hero p br{display:none}.hero-actions{align-items:stretch;flex-direction:column;max-width:300px}.hero-mini{margin-top:33px}.hero-bottom{font-size:8px}.hero-bottom span:last-child{display:none}.section-heading{font-size:31px}.intro,.curriculum-section,.laboratory-section,.patterns-section,.challenge-section,.glossary-section{padding-top:69px;padding-bottom:76px}.section-lead{font-size:13px}.feature-grid,.lessons-grid,.glossary-grid{grid-template-columns:1fr}.feature-card,.feature-card:last-child{grid-column:auto;min-height:190px}.feature-card h3{margin-top:16px}.curriculum-tools{margin-top:30px}.search-wrap{width:100%}.lesson-card{min-height:163px}.lesson-card h3{margin:9px 0 2px}.patterns-grid{grid-template-columns:1fr 1fr;gap:9px}.pattern-card{padding:11px;min-height:270px}.pattern-diagram{height:115px}.pattern-card p{font-size:10px}.pattern-card h3{font-size:14px}.lab-toolbar{padding:14px;gap:12px}.control-set select{min-width:135px}.chart-title-row{padding:17px 14px 10px}.chart-title-row strong{font-size:10px}.chart-last strong{font-size:18px}.overlays{gap:9px;padding:8px 13px 13px}.overlays label{font-size:10px}.chart-wrap{height:290px}.osc-wrap{height:125px}.osc-title{margin:0 13px}.replay-controls{padding:14px}.replay-controls input[type=range]{order:2;flex-basis:100%}.analysis-summary{padding:19px}.analysis-top{flex-wrap:wrap}.analysis-top small{margin:0}.legend{font-size:10px}.quiz-card{padding:20px}.quiz-card h3{font-size:18px;min-height:0}.final-content{padding:27px 20px}.final-content p{font-size:12px}.footer-bottom{flex-direction:column;gap:7px}.lesson-content{padding:26px 19px}.lesson-content h2{font-size:27px}.lesson-content .lead{font-size:14px}.lesson-footer{flex-direction:column;align-items:stretch}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;animation-duration:.001ms!important;transition-duration:.001ms!important}}
/* Keep decorative glows and the small-screen menu inside the viewport. */
.ambient-two{right:0;width:370px}
.mobile-nav{z-index:45}
@media(max-width:800px){.ambient{display:none}}

/* A subtle original WebP detail on the first learning path tile. */
.feature-blue{background-image:linear-gradient(110deg,rgba(12,28,45,.96),rgba(16,34,50,.84)),url("assets/explore-lab.webp");background-position:center;background-size:cover}