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/* V4 polish: editorial clarity, faithful ACE logo, guided learning gates */
body{font-size:16px;line-height:1.68}
.paper{border-radius:11px;box-shadow:0 6px 28px rgba(21,42,24,.045);min-height:600px}
.paper h1{letter-spacing:-.035em}
.two{grid-template-columns:minmax(0,1.48fr) minmax(250px,.66fr)}
.copy p{font-size:16px;line-height:1.83;margin-bottom:19px;max-width:76ch}
.key-points{margin:27px 0 12px;padding:22px 26px;background:#f4f7f2;border:1px solid #dfe8dd;border-radius:9px}
.key-points h3{font-size:16px;margin:0 0 9px;color:var(--pine)}
.key-points .points{margin-top:0}
.lesson-aside{padding:25px 23px;background:#f7f9f6;border:1px solid #e1e7dd;border-radius:10px;color:#3c5646;position:relative}
.lesson-aside strong{font-size:21px;color:#274b36;display:block;line-height:1.35}
.lesson-aside p{font-size:14px;line-height:1.75}
.aside-line{display:block;height:3px;width:45px;background:var(--green);margin:26px 0 12px}
.lesson-aside .aside-small{font-size:12px;color:#788b7c}
.course-hero{background:linear-gradient(135deg,#f5f8f3,#eaf0e9);padding:38px}
.stats-inline{color:#3a5844;font-weight:650}
.chapter.locked{cursor:not-allowed;opacity:.53}
.chapter.locked:hover{background:transparent}
.locked-label{display:block;font-size:10px;font-weight:400;color:#718274}
.overview-item:disabled{opacity:.49;cursor:not-allowed}
.card-toggle{display:block;text-align:left;cursor:pointer;color:inherit;width:100%;transition:border-color .15s ease,background .15s ease}
.card-toggle:hover{border-color:#669871;background:#f6faf5}
.card-toggle.reviewed{border-color:#99b89b;background:#fbfdf9}
.card-toggle .card-action{color:#327447;font-size:12px;display:block;margin-top:19px;font-weight:800}
.card-toggle p{line-height:1.7}
.card-toggle .index{text-transform:uppercase}
.activity-tip{font-size:14px;font-weight:600;color:#45634c;margin:14px 0 20px;line-height:1.6}
.scenario-brief{background:#eff5ef;border-left:4px solid #568c56;padding:21px 25px}
.scenario-brief p{font-size:17px;line-height:1.8}
.gatehint{color:#526d54;font-size:13px;font-weight:700;margin-bottom:6px;text-align:center;max-width:320px}
.controls{gap:12px;position:sticky;bottom:0;z-index:5;box-shadow:0 -8px 22px rgba(255,255,255,.84)}
.step{display:flex;flex-direction:column;align-items:center}
.step-track{max-width:100%;width:180px}
.quizblock{max-width:900px;background:#fcfdfb}
.quizblock h3{font-size:21px}
.pick.visited:after{content:' ✓';color:#1f6c39}
.diagram.paused .particle{animation-play-state:paused}
.animation-toggle{margin:10px 0 0}
.exam-item{min-width:0;border:0;border-bottom:1px solid #e5e8e3;margin:0;padding:25px 0}
.exam-item legend{font-weight:750;font-size:17px;line-height:1.5;margin-bottom:11px}
.exam-item label{display:block;border:1px solid #e0e7df;margin:8px 0;padding:12px;border-radius:7px}
.exam-item label:has(input:checked){border-color:#86aa88;background:#f1f8f0}
.screen-mark{float:right;color:#718071;font-size:12px;letter-spacing:0;text-transform:none}
.muted{background:#f6f8f4;color:#566453;border-color:#becbbf}
.source-photo figcaption{font-size:11px;padding:11px;line-height:1.6;color:#5b6a60}
@media(max-width:950px){.two{grid-template-columns:1fr}.lesson-aside{max-width:650px}}
@media(max-width:750px){.copy p{font-size:15px}.controls{position:sticky;bottom:0}.gatehint{max-width:155px;font-size:10px}.paper-body{padding:25px 19px}.course-hero{padding:22px}.screen-mark{float:none;display:block;margin-top:5px}}

/* ACE EnviroScience: typographic brand wordmark and learner experience */
.logo{position:relative;display:flex;gap:0;align-items:baseline;white-space:nowrap;padding-bottom:15px}.logo .brand-ace,.brand-lockup .brand-ace{font-size:30px;font-weight:720;letter-spacing:-.07em;color:#718a2c;line-height:1}.logo .brand-enviro,.brand-lockup .brand-enviro{font-size:30px;font-weight:300;letter-spacing:-.065em;color:#1d2424;margin-left:14px;line-height:1}.logo .brand-tagline{position:absolute;right:0;bottom:2px;letter-spacing:.28em;font-size:7px;color:#6e7774;font-weight:550}.learner-top{font-size:12px;color:#53635b}.account-button{border:1px solid #cedbd0;background:white;border-radius:7px;color:#254c34;padding:8px 12px;font-size:13px;font-weight:700}
#ace-portal-overlay{display:grid;place-items:center;position:fixed;inset:0;z-index:50;background:rgba(16,30,23,.48);padding:18px;overflow:auto;backdrop-filter:blur(3px)}.portal-card{width:min(520px,100%);background:#fff;border:1px solid #d6e2d6;border-radius:15px;box-shadow:0 16px 65px #17251b45;padding:34px;max-height:95vh;overflow:auto}.brand-lockup{display:flex;align-items:baseline;flex-wrap:wrap;margin-bottom:26px;position:relative;padding-bottom:20px}.brand-lockup .brand-ace,.brand-lockup .brand-enviro{font-size:37px}.brand-lockup small{position:absolute;right:4px;bottom:0;letter-spacing:.25em;font-size:8px;color:#777}.portal-card h2{margin:6px 0 6px;font-size:29px;line-height:1.2;letter-spacing:-.04em}.portal-card p{font-size:14px;color:#516157}.portal-label{font-size:11px;font-weight:750;letter-spacing:.12em;color:#628027}.portal-note{border-left:3px solid #749534;background:#f2f5eb;padding:12px 16px;margin:22px 0}.portal-note strong{font-size:10px;letter-spacing:.12em;color:#496a2b}.portal-note p{margin:4px 0 0}.portal-card form label{display:block;font-size:13px;color:#455c4f;font-weight:650;margin:12px 0}.portal-card input{display:block;width:100%;margin-top:6px;padding:13px;border:1px solid #cbd7ce;border-radius:7px;font:inherit;font-size:15px}.portal-primary{display:block;width:100%;background:#315c35;border:1px solid #315c35;color:white;padding:12px 15px;border-radius:8px;font:inherit;font-size:14px;font-weight:700;margin:15px 0;cursor:pointer}.portal-secondary{color:#315c35;background:white}.portal-text{border:0;background:transparent;color:#315c35;font-size:13px;text-decoration:underline;margin-top:10px;cursor:pointer}.portal-dash{display:grid;gap:11px;padding:14px 0}.portal-dash>div{background:#f5f7f2;border:1px solid #e0e6dc;border-radius:8px;padding:11px 14px}.portal-dash span{display:block;font-size:11px;color:#5b7061}.portal-dash strong{display:block;font-size:15px}.portal-email{border:1px solid #d8dfd9;background:#fbfcfb;padding:15px;font-size:13px;line-height:1.8}.portal-cert{margin:25px 0;padding:20px;border:1px solid #cbdcc6;background:#f4f8f1;border-radius:10px}.portal-cert h2,.portal-cert h3{margin:0}.portal-cert .btn{margin:6px 6px 6px 0}
@media(max-width:750px){.top{gap:8px}.logo .brand-ace,.logo .brand-enviro{font-size:22px}.logo .brand-tagline{font-size:6px;letter-spacing:.13em}.learner-top,.tag{display:none}.top-right{gap:5px}.account-button{font-size:11px;padding:7px 9px}.portal-card{padding:22px}}