:root{--ink:#10131b;--paper:#f7f6f1;--white:#fff;--teal:#10a9bd;--teal-dark:#087889;--pink:#d8348c;--violet:#51237d;--line:#d8d9dc;--muted:#5d6470;--radius:20px}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;font-size:17px;line-height:1.55}.topbar{height:76px;padding:0 clamp(22px,5vw,76px);display:flex;align-items:center;justify-content:space-between;background:rgba(247,246,241,.94);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20;backdrop-filter:blur(10px)}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;color:var(--ink);font-size:16px}.brand b{display:block}.microbe{display:grid;place-items:center;width:40px;height:40px;border-radius:50%;background:var(--ink);color:#55d4e0;font-size:27px}.topbar nav{display:flex;gap:26px}.topbar nav a{color:var(--ink);font-size:15px;text-decoration:none;font-weight:700}.topbar nav a:hover{color:var(--pink)}.hero{min-height:590px;padding:90px clamp(22px,8vw,130px);display:grid;grid-template-columns:1.05fr .95fr;align-items:center;overflow:hidden}.hero-copy{max-width:660px}.eyebrow{font-size:13px;letter-spacing:.15em;font-weight:900;color:var(--pink);margin:0 0 14px}.hero h1{font-size:clamp(48px,6.5vw,92px);line-height:.95;letter-spacing:-.055em;margin:0 0 30px}.hero h1 span{color:var(--teal-dark)}.hero-copy>p:not(.eyebrow){max-width:560px;font-size:20px;margin-bottom:32px}.button{border:0;border-radius:999px;padding:13px 20px;display:inline-flex;gap:12px;align-items:center;justify-content:center;font:inherit;font-weight:800;text-decoration:none;cursor:pointer}.primary{background:var(--ink);color:white}.primary:hover{background:var(--pink)}.light{background:white;color:var(--ink)}.light:hover{background:#dff7fa}.ghost{background:transparent;border:1px solid var(--line);color:var(--ink)}.cell-art{width:min(35vw,470px);aspect-ratio:1.45;border:12px double var(--teal);border-radius:48% 52% 44% 56%;position:relative;transform:rotate(-8deg);background:radial-gradient(circle at 25% 30%,#fdfdfd 0 4%,transparent 5%),radial-gradient(circle at 70% 68%,#efb3d2 0 5%,transparent 6%),repeating-radial-gradient(circle at 40% 50%,transparent 0 13px,rgba(11,166,186,.09) 14px 16px);box-shadow:inset 0 0 0 9px rgba(216,52,140,.18),0 28px 60px rgba(50,35,90,.14)}.cell-core{position:absolute;inset:18%;border-radius:48%;border:4px dashed var(--violet)}.cell-core b{position:absolute;inset:24%;border:6px solid var(--pink);border-radius:50%;transform:skew(15deg)}.cell-core i{position:absolute;width:16px;height:16px;background:var(--teal);border-radius:50%}.cell-core i:nth-child(1){left:8%;top:20%}.cell-core i:nth-child(2){right:6%;top:15%}.cell-core i:nth-child(3){right:13%;bottom:13%}.cell-core i:nth-child(4){left:17%;bottom:8%}.strand{position:absolute;width:70%;height:80px;border-top:6px solid var(--pink);border-radius:50%;right:-62%;top:20%}.strand.s2{top:44%;border-color:var(--teal);transform:rotate(8deg)}.strand.s3{top:67%;border-color:var(--violet);transform:rotate(-7deg)}.section{padding:86px clamp(22px,8vw,130px);scroll-margin-top:75px}.section-heading{display:flex;justify-content:space-between;align-items:end;gap:30px;margin-bottom:38px}.section-heading h2,.chapter-head h2{font-size:clamp(38px,5vw,62px);line-height:1;letter-spacing:-.04em;margin:0}.section-heading>p{max-width:390px;color:var(--muted)}.lot-grid{display:grid;grid-template-columns:1.25fr 1fr 1fr;gap:18px}.lot-card{min-height:280px;border:1px solid var(--line);border-radius:var(--radius);padding:28px;color:var(--ink);text-decoration:none;position:relative;background:white}.lot-card.active{background:linear-gradient(145deg,#0b8091,#12b6c6);color:white;border:0}.lot-card .number{font-size:36px;font-weight:950;opacity:.28}.status{position:absolute;right:22px;top:26px;font-size:12px;letter-spacing:.12em;font-weight:900;padding:6px 10px;border:1px solid currentColor;border-radius:999px}.lot-card h3{font-size:27px;line-height:1.05;margin:45px 0 10px}.lot-card p{margin:0;opacity:.82}.card-link{display:block;margin-top:20px;font-weight:900}.future{background:transparent}.dark{background:var(--ink);color:white}.dark .eyebrow{color:#52d5df}.chapter-head{display:flex;align-items:end;justify-content:space-between;gap:24px;border-bottom:1px solid #3b3f48;padding-bottom:28px}.lead{font-size:21px;color:#c5cad2}.chapter-tabs,.exercise-nav{display:flex;gap:8px}.tab,.exercise-pill{border:1px solid #575c66;background:transparent;color:white;border-radius:999px;padding:11px 20px;font:inherit;font-weight:800;cursor:pointer}.tab.active{background:var(--pink);border-color:var(--pink)}.tab-panel,.exercise-panel{display:none}.tab-panel.active,.exercise-panel.active{display:block}.learn-path{display:grid;grid-template-columns:1fr 1fr;gap:18px;margin-top:28px}.resource{border:1px solid #3b3f48;border-radius:var(--radius);padding:25px;background:#181c25;min-width:0}.resource h3{font-size:24px;line-height:1.2;margin:10px 0 18px}.tag{display:inline-block;color:#51d1dd;font-size:12px;letter-spacing:.13em;font-weight:900}.resource video{width:100%;aspect-ratio:16/9;border-radius:12px;background:#07090d}.resource audio{width:100%;margin:10px 0}.hint{color:#aeb5c0;font-size:15px}.book,.pdf-card{display:flex;justify-content:space-between;gap:24px}.book-pages{display:flex;align-items:center}.book-pages span{width:62px;height:92px;margin-left:-25px;display:grid;place-items:center;border:2px solid #10131b;background:#f9f5e9;color:var(--ink);font-weight:950;box-shadow:0 6px 18px #0006;transform:rotate(6deg)}.book-pages span:nth-child(2){transform:rotate(-4deg);background:#dff7fa}.book-pages span:nth-child(3){transform:rotate(9deg);background:#f8cfe4}.pdf-symbol{width:100px;height:100px;flex:0 0 100px;border:3px solid var(--pink);color:#ff67b3;border-radius:50%;display:grid;place-items:center;font-size:34px;font-weight:950;line-height:.7}.pdf-symbol span{display:block;font-size:9px;letter-spacing:.1em}.coming{margin-top:28px;min-height:310px;border:1px dashed #555b66;border-radius:var(--radius);display:flex;align-items:center;justify-content:center;gap:28px;text-align:left}.coming>span{font-size:76px;color:var(--teal)}.coming h3{font-size:31px;margin:0}.coming p:last-child{max-width:570px;color:#bdc3cd}.exercises{background:white}.exercise-nav{margin-bottom:24px}.exercise-pill{color:var(--ink);border-color:var(--line)}.exercise-pill.active{color:white;background:var(--violet);border-color:var(--violet)}.exercise-panel{border:1px solid var(--line);border-radius:var(--radius);padding:32px;background:var(--paper)}.flash-wrap{max-width:720px;margin:auto;text-align:center}.counter{font-size:12px;letter-spacing:.13em;font-weight:900;color:var(--muted)}.flashcard{width:100%;min-height:280px;border:0;border-radius:var(--radius);padding:35px;background:var(--violet);color:white;box-shadow:0 15px 36px #39205724;cursor:pointer}.flashcard strong{font-size:clamp(34px,6vw,58px);display:block}.flash-label{font-size:12px;letter-spacing:.15em;color:#e9bcff;font-weight:900}.flash-answer{display:none;font-size:21px;max-width:520px;margin:20px auto}.flashcard.revealed .flash-answer{display:block}.flashcard.revealed strong{font-size:30px}.flashcard small{display:block;margin-top:28px;opacity:.7}.controls{display:flex;justify-content:center;gap:10px;margin-top:18px}.match-header{display:flex;justify-content:space-between;align-items:center}.text-button{border:0;background:none;text-decoration:underline;font:inherit;font-weight:800;cursor:pointer}.match-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.match-column{display:grid;gap:10px}.match-item{border:2px solid transparent;background:white;border-radius:12px;padding:16px;text-align:left;font:inherit;cursor:pointer;min-height:64px}.match-item:hover,.match-item.selected{border-color:var(--pink)}.match-item.matched{background:#d9f5ef;color:#146252;opacity:.7;pointer-events:none}.match-item.wrong{animation:shake .25s;border-color:#bd1f3f}.feedback{font-weight:800;min-height:28px}.feedback.ok{color:#13715b}.feedback.no{color:#aa2140}@keyframes shake{25%{transform:translateX(-5px)}75%{transform:translateX(5px)}}.reading-card{display:grid;grid-template-columns:1fr 1fr;gap:35px}.reading-text{background:var(--ink);color:white;padding:30px;border-radius:16px}.reading-text h3{font-size:28px}.question{padding:12px}.question h3{font-size:24px}.answers{display:grid;gap:10px}.answer{background:white;border:2px solid var(--line);border-radius:12px;padding:14px;text-align:left;font:inherit;cursor:pointer}.answer:hover{border-color:var(--teal)}.answer.correct{border-color:#1b9a78;background:#d9f5ef}.answer.incorrect{border-color:#c53055;background:#fde2e9}.hidden{display:none!important}footer{padding:28px clamp(22px,8vw,130px);display:flex;justify-content:space-between;border-top:1px solid var(--line);font-weight:750}footer a{color:var(--ink)}
@media(max-width:850px){.topbar nav{display:none}.hero{grid-template-columns:1fr;padding-top:55px}.cell-art{width:min(85vw,450px);margin:60px 0 0}.lot-grid,.learn-path,.reading-card{grid-template-columns:1fr}.section-heading,.chapter-head{align-items:flex-start;flex-direction:column}.chapter-tabs{width:100%}.tab{flex:1}.book,.pdf-card{align-items:center}.match-grid{grid-template-columns:1fr}.match-header{align-items:flex-start;gap:12px}.hero h1{font-size:52px}.section{padding-top:64px;padding-bottom:64px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important}}
.lot-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
.unit-intro{padding-top:72px}.unit-intro h1{font-size:clamp(42px,6vw,72px);line-height:1;letter-spacing:-.045em;margin:0}.placeholder-main{min-height:calc(100vh - 76px);padding:clamp(30px,8vw,100px);display:grid;place-items:center;background:linear-gradient(145deg,var(--ink),#28203c)}.placeholder-card{position:relative;width:min(840px,100%);padding:clamp(36px,7vw,78px);border-radius:var(--radius);background:var(--paper)}.placeholder-card h1{font-size:clamp(42px,7vw,78px);line-height:1;letter-spacing:-.05em;margin:0 0 26px;max-width:740px}.placeholder-card>p:not(.eyebrow){font-size:20px;color:var(--muted);max-width:650px;margin-bottom:34px}.placeholder-card .status{color:var(--pink)}
.reading-picker{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:22px}.reading-choice{border:1px solid var(--line);background:white;color:var(--ink);border-radius:999px;padding:10px 17px;font:inherit;font-weight:800;cursor:pointer}.reading-choice.active{background:var(--teal-dark);border-color:var(--teal-dark);color:white}.quiz-wide{max-width:760px;margin:auto;background:white;border-radius:16px;padding:clamp(24px,5vw,48px)}.quiz-wide h3{font-size:clamp(25px,4vw,36px);line-height:1.2;margin:8px 0}.multi-help{color:var(--muted);margin-top:0}
.path-links{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:8px}.path-links a{border:1px solid #575c66;border-radius:999px;padding:10px 16px;color:white;text-decoration:none;font-weight:800;font-size:15px}.path-links a:hover{background:var(--pink);border-color:var(--pink)}.topic-block{padding:54px 0 12px;scroll-margin-top:76px}.topic-block+.topic-block{margin-top:42px;border-top:1px solid #3b3f48}.topic-heading{display:grid;grid-template-columns:auto minmax(0,720px);gap:22px;align-items:start;margin-bottom:24px}.topic-number{font-size:clamp(44px,7vw,78px);font-weight:950;line-height:.9;color:#333945}.topic-heading h2{font-size:clamp(36px,5vw,58px);line-height:1;margin:0 0 12px;letter-spacing:-.04em}.topic-heading p:last-child{color:#c5cad2;font-size:18px;margin:0}.virus-poster{margin:26px 0 18px;border-radius:var(--radius);overflow:hidden;background:white}.virus-poster img{display:block;width:100%;height:auto}.virus-resources{align-items:stretch}.audio-wide audio{width:100%;margin-top:10px}.key-points ul{margin:12px 0 0;padding-left:22px}.key-points li{margin:7px 0}.virus-mark{border-color:var(--teal);color:#56d9e4}.compare-block{padding-bottom:28px}.compare-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.compare-grid article{padding:26px;border:1px solid #3b3f48;border-radius:var(--radius);background:#181c25}.compare-grid h3{font-size:27px;margin:0 0 10px}.compare-grid p{color:#c5cad2;margin:0}.reading-text p{white-space:pre-line}
@media(max-width:850px){.path-links{justify-content:flex-start}.topic-heading{grid-template-columns:1fr;gap:8px}.topic-number{font-size:40px}.compare-grid{grid-template-columns:1fr}.virus-poster{border-radius:12px}}
.completed{background:#fff}.completed .status{color:var(--teal-dark)}.motion-icon{display:grid;place-items:center;width:40px;height:40px;border-radius:50%;background:var(--ink);color:#ffcc4d;font-size:25px;font-weight:900}.motion-hero{min-height:540px;padding:75px clamp(22px,8vw,130px);display:grid;grid-template-columns:1.05fr .95fr;gap:50px;align-items:center;background:linear-gradient(145deg,#f7f6f1 0 58%,#f0c84b 58%)}.motion-hero h1{font-size:clamp(54px,8vw,100px);line-height:.87;letter-spacing:-.065em;margin:0 0 28px}.motion-hero h1 span{color:#225ab6}.motion-lead{font-size:21px;max-width:560px}.hero-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:28px}.motion-graphic{height:330px;position:relative;overflow:hidden}.track{position:absolute;left:3%;right:3%;bottom:50px;height:8px;background:var(--ink);transform:rotate(-8deg)}.ball{position:absolute;width:110px;height:110px;border-radius:50%;left:30%;bottom:100px;background:radial-gradient(circle at 32% 28%,#fff 0 6%,#11aabd 7% 35%,#087889 70%);box-shadow:0 25px 35px #10131b33}.force-arrow{position:absolute;left:4%;bottom:170px;width:210px;border-bottom:8px solid var(--pink);color:var(--pink);font-size:32px;font-weight:950}.force-arrow:after{content:"";position:absolute;right:-2px;bottom:-17px;border-left:24px solid var(--pink);border-top:13px solid transparent;border-bottom:13px solid transparent}.speed-lines{position:absolute;left:2%;bottom:115px;width:170px;height:50px;border-top:5px solid var(--teal-dark);border-bottom:5px solid var(--teal-dark)}.calendar-note{padding:18px 22px;margin-bottom:18px;border-left:5px solid var(--pink);background:#fff;border-radius:0 12px 12px 0}.schedule-wrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:#fff}.course-table{width:100%;border-collapse:collapse;min-width:860px}.course-table th,.course-table td{padding:17px 18px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}.course-table thead{background:var(--ink);color:#fff}.course-table tbody th{font-size:21px;color:var(--pink);width:70px}.course-table td:nth-child(2),.course-table td:nth-child(3){white-space:nowrap;font-weight:800;width:135px}.course-table td:last-child>a:not(.mini-link){display:inline;font-size:19px;font-weight:900;color:#175fc1}.course-table td span{display:block;margin:4px 0}.mini-link{display:inline-flex;margin:6px 7px 0 0;padding:6px 10px;border-radius:999px;background:#edf1f6;color:var(--ink);font-size:14px;font-weight:750;text-decoration:none}.assessment-row{background:#fff3d1}.project-row{background:#e9f7f9}.review-section{background:var(--ink);color:#fff}.review-section .section-heading>p{color:#c8ced8}.chapter-review-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}.review-card{border:1px solid #3f4652;border-radius:16px;background:#181d27;overflow:hidden}.review-card summary{display:flex;align-items:center;gap:14px;padding:20px;cursor:pointer;list-style:none;font-size:21px}.review-card summary::-webkit-details-marker{display:none}.review-card summary span{color:#5cdae3;font-size:14px;font-weight:900;letter-spacing:.08em}.review-card summary:after{content:"+";margin-left:auto;color:#f3cf58;font-size:28px}.review-card[open] summary:after{content:"−"}.review-card>div{padding:0 20px 22px;color:#d1d5dc}.review-card ul{padding-left:20px}.formula{display:inline-block;margin:8px 0 16px;padding:9px 14px;border-radius:8px;background:#282f3c;color:#f6d35f;font-weight:900}.review-start{display:block;border:0;border-radius:999px;padding:10px 16px;background:#fff;color:var(--ink);font:inherit;font-weight:850;cursor:pointer}.review-quiz{max-width:820px;margin:30px auto 0;padding:32px;border-radius:var(--radius);background:var(--paper);color:var(--ink)}.review-quiz h3{font-size:30px;margin:0}.review-quiz #reviewQuestion{font-size:21px;font-weight:750}.final-project{background:#f0c84b}.final-project h2{font-size:clamp(42px,6vw,72px);line-height:1;margin:0 0 20px}.final-project>p:not(.eyebrow){max-width:760px;font-size:21px}.final-project ol{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;counter-reset:step;padding:0;list-style:none}.final-project li{padding:22px;background:#fff;border-radius:14px}.final-project li:before{counter-increment:step;content:counter(step);display:grid;place-items:center;width:32px;height:32px;margin-bottom:14px;border-radius:50%;background:var(--ink);color:#fff;font-weight:900}
@media(max-width:850px){.motion-hero{grid-template-columns:1fr;background:linear-gradient(180deg,#f7f6f1 0 68%,#f0c84b 68%)}.motion-graphic{height:250px}.chapter-review-grid{grid-template-columns:1fr}.final-project ol{grid-template-columns:1fr 1fr}.course-table th,.course-table td{padding:13px}}
@media(max-width:520px){.final-project ol{grid-template-columns:1fr}.motion-hero h1{font-size:58px}}

/* Kafli 1.1 — Hreyfing */
.review-link{width:max-content;text-decoration:none}.motion-chapter{background:#f7f4eb;color:#173a35}.chapter-topbar{background:rgba(247,244,235,.95)}.chapter-brand{display:flex;align-items:center;gap:16px}.chapter-brand a{color:#173a35;font-weight:900;text-decoration:none}.chapter-brand span{padding:6px 10px;border-radius:999px;background:#f0c84b;font-size:13px;font-weight:900}.motion-chapter-hero{min-height:520px;padding:80px max(7vw,36px);display:grid;grid-template-columns:1.15fr .65fr;align-items:center;gap:65px;background:linear-gradient(135deg,#f9f5e9,#d7eaf0)}.motion-chapter-hero h1{font-family:Georgia,serif;font-size:clamp(64px,9vw,118px);line-height:.9;letter-spacing:-.05em;margin:12px 0 25px}.motion-chapter-hero p:not(.eyebrow){max-width:680px;font-size:20px;line-height:1.6}.motion-chapter-mark{position:relative;aspect-ratio:1;border-radius:50%;display:grid;place-items:center;background:#fff9;box-shadow:inset 0 0 0 24px #ffffff35;overflow:hidden}.motion-chapter-mark b{position:relative;z-index:2;padding:14px 20px;border-radius:14px;background:#173f38;color:#fff;font-family:Georgia,serif;font-size:clamp(28px,4vw,48px)}.motion-chapter-mark i{position:absolute;width:66px;height:66px;left:16%;top:25%;border-radius:50%;background:#e2478f;box-shadow:0 12px 20px #102e2933}.mini-road{position:absolute;width:90%;height:70px;bottom:19%;background:#33434a;transform:rotate(-12deg)}.mini-road:after{content:"";position:absolute;left:4%;right:4%;top:32px;border-top:5px dashed #fff}.chapter-goals{padding:27px max(7vw,36px);display:grid;grid-template-columns:1.2fr repeat(3,1fr);gap:18px;background:#173f38;color:#fff;align-items:center}.chapter-goals span{line-height:1.4}.chapter-section{padding:95px max(6vw,30px);scroll-margin-top:76px}.chapter-section-heading{max-width:820px;margin-bottom:42px}.chapter-section-heading h2{font-family:Georgia,serif;font-size:clamp(42px,5vw,68px);line-height:1.02;margin:8px 0 14px}.chapter-section-heading>p:last-child{font-size:18px;line-height:1.55}.materials-section{background:#f8f2e6}.motion-material-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.motion-material{min-height:250px;border:1px solid #dedbcf;border-radius:22px;background:#fff;box-shadow:0 12px 28px #173f3810;overflow:hidden;display:flex;flex-direction:column}.motion-material:hover{transform:translateY(-3px);box-shadow:0 18px 34px #173f3820}.material-copy{padding:28px;display:flex;flex:1;flex-direction:column}.material-icon{font-size:38px}.motion-material small{margin-top:14px;color:#176ca8;font-weight:900;letter-spacing:.12em}.motion-material h3{font-family:Georgia,serif;font-size:28px;margin:7px 0 10px}.motion-material p{line-height:1.55;margin:0 0 20px}.motion-material a{margin-top:auto;color:#176ca8;font-weight:900;text-decoration:none}.motion-material img,.motion-material video{display:block;width:100%;max-height:410px;object-fit:contain;background:#102e29}.motion-material iframe{width:100%;height:390px;border:0;background:#eee}.motion-material audio{width:calc(100% - 56px);margin:0 28px 28px}.motion-material.featured{grid-column:1/-1;min-height:0;background:linear-gradient(125deg,#173f38,#28544d);color:#fff}.motion-material.featured .material-copy{display:grid;grid-template-columns:auto 1fr auto;column-gap:22px;align-items:center}.motion-material.featured .material-icon{grid-row:1/4;width:72px;height:72px;border-radius:18px;background:#fff;display:grid;place-items:center}.motion-material.featured small{margin:0;color:#f3d77d}.motion-material.featured h3{margin:5px 0}.motion-material.featured p{margin:0;color:#dce9e6}.motion-material.featured a{grid-column:3;grid-row:1/4;padding:13px 18px;border-radius:999px;background:#f3d77d;color:#173f38}.motion-concept-lab{max-width:1160px;margin:auto;display:grid;grid-template-columns:.9fr 1.1fr;gap:24px}.motion-concept-list{display:grid;grid-template-columns:1fr 1fr;gap:10px}.motion-concept-list button{padding:16px 18px;border:1px solid #d4dad6;border-radius:16px;background:#fff;text-align:left;display:flex;flex-direction:column;gap:4px;cursor:pointer}.motion-concept-list button.active{border:2px solid #176ca8;background:#eef8fb}.motion-concept-list b{font-size:17px}.motion-concept-list span{color:#687773}.motion-concept-detail{min-height:340px;padding:38px;border-radius:24px;background:#173f38;color:#fff;display:flex;flex-direction:column;justify-content:center}.motion-concept-detail small{font-weight:900;letter-spacing:.15em;color:#f3d77d}.motion-concept-detail h3{font-family:Georgia,serif;font-size:43px;margin:10px 0 20px}.motion-concept-detail p{font-size:19px;line-height:1.65}.motion-quiz-section{background:#eee8dc}.motion-quiz-grid{max-width:1150px;margin:auto;display:grid;grid-template-columns:1fr 1fr;gap:18px}.motion-quiz-grid article{padding:25px;border-radius:20px;background:#fff;border:1px solid #dce1dc}.motion-quiz-grid h3{font-family:Georgia,serif;font-size:21px;line-height:1.35}.quiz-options{display:grid;gap:8px}.quiz-options button,.graph-options button{padding:12px 14px;border:1px solid #ccd6d4;border-radius:12px;background:#f7f7f3;text-align:left;cursor:pointer}.quiz-options button.correct,.graph-options button.correct,.scenario-list button.correct{background:#dcefe1;border-color:#5c9970}.quiz-options button.wrong,.graph-options button.wrong,.scenario-list button.wrong{background:#fae2da;border-color:#d17b62}.quiz-feedback,.calc-feedback,.graph-feedback{min-height:48px;margin-bottom:0;font-weight:800}.good{color:#39744b}.try{color:#a14f39}.motion-score{max-width:1150px;margin:24px auto 0;display:grid;grid-template-columns:auto 1fr;gap:18px;align-items:center;font-weight:900}.motion-score>div{height:13px;border-radius:99px;background:#d3d1c9;overflow:hidden}.motion-score i{display:block;width:0;height:100%;background:#4d8c68;transition:.3s}.calculation-section{background:#173f38;color:#fff}.calculation-section .eyebrow{color:#f3d77d}.formula-triangle{width:220px;margin:0 auto 34px;display:grid;grid-template-columns:1fr 1fr;clip-path:polygon(50% 0,100% 100%,0 100%);background:linear-gradient(180deg,#f0c84b 0 49%,#2f87c1 50%);color:#102e29;text-align:center;padding:35px 34px 18px;font-family:Georgia,serif;font-size:29px}.formula-triangle strong{grid-column:1/-1;padding-bottom:21px;border-bottom:3px solid #fff}.formula-triangle span{padding-top:9px;color:#fff}.formula-triangle span+span{border-left:3px solid #fff}.calculation-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}.calculation-grid article{padding:26px;border-radius:20px;background:#fff;color:#173a35}.calculation-grid small{font-weight:900;letter-spacing:.12em;color:#176ca8}.calculation-grid h3{font-family:Georgia,serif;font-size:27px;margin:8px 0}.calculation-grid label{display:flex;align-items:center;justify-content:space-between;gap:10px;font-weight:900}.calculation-grid input{width:130px;padding:11px;border:1px solid #b9c5c2;border-radius:10px;font:inherit}.calculation-grid button{margin-top:15px;padding:10px 14px;border:0;border-radius:999px;background:#173f38;color:#fff;font-weight:900;cursor:pointer}.graph-section{background:#f6efdF}.graph-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.graph-grid article{padding:24px;border-radius:20px;background:#fff}.graph-grid h3{font-family:Georgia,serif;font-size:25px;margin:0}.graph-grid svg{width:100%;max-height:230px;margin:12px 0;background:#f6fbfc;border-radius:14px}.graph-grid .axes{fill:none;stroke:#173f38;stroke-width:4}.graph-grid .data-line{fill:none;stroke:#e2478f;stroke-width:7;stroke-linecap:round}.graph-grid text{font-size:18px;font-weight:900;fill:#173f38}.graph-options{display:grid;gap:7px}.scenario-section{background:#e7f2f2}.scenario-list{display:grid;gap:12px}.scenario-list article{display:grid;grid-template-columns:auto 1fr;gap:12px 18px;align-items:center;padding:20px 22px;border-radius:18px;background:#fff}.scenario-list article>span{grid-row:1/3;width:42px;height:42px;border-radius:50%;display:grid;place-items:center;background:#176ca8;color:#fff;font-weight:900}.scenario-list p{margin:0;font-weight:800}.scenario-list article>div{display:flex;flex-wrap:wrap;gap:7px}.scenario-list button{padding:8px 11px;border:1px solid #cad5d2;border-radius:999px;background:#f7f7f3;cursor:pointer}.scenario-list small{grid-column:2;min-height:20px;font-weight:800}.chapter-finish{padding:55px max(7vw,36px);display:flex;justify-content:space-between;align-items:center;gap:30px;background:#f0c84b}.chapter-finish h2{font-family:Georgia,serif;font-size:32px;margin:7px 0}.chapter-finish a{padding:14px 19px;border-radius:99px;background:#173f38;color:#fff;text-decoration:none;font-weight:900;white-space:nowrap}
@media(max-width:900px){.motion-chapter-hero{grid-template-columns:1fr}.motion-chapter-mark{max-width:360px;width:75%;margin:auto}.chapter-goals{grid-template-columns:1fr 1fr}.motion-concept-lab{grid-template-columns:1fr}.graph-grid{grid-template-columns:1fr}.chapter-topbar nav{display:none}}
@media(max-width:700px){.motion-material-grid,.motion-quiz-grid,.calculation-grid{grid-template-columns:1fr}.motion-material.featured .material-copy{grid-template-columns:auto 1fr}.motion-material.featured a{grid-column:1/-1;grid-row:auto;text-align:center;margin-top:18px}.motion-concept-list{grid-template-columns:1fr}.chapter-goals{grid-template-columns:1fr}.chapter-finish{align-items:flex-start;flex-direction:column}.scenario-list article{grid-template-columns:auto 1fr}.motion-chapter-hero,.chapter-section{padding-left:20px;padding-right:20px}}

/* Kafli 1.2 — Kraftar */
.force-chapter{--force-blue:#315fbd;--force-orange:#ef7a31}.force-hero{background:linear-gradient(135deg,#f8f4e9,#dce5f7)}.force-hero h1{color:#173f38}.force-mark{position:relative;aspect-ratio:1;border-radius:50%;display:grid;place-items:center;background:#fff9;box-shadow:inset 0 0 0 24px #ffffff35}.force-mark span{width:118px;height:118px;border-radius:28px;display:grid;place-items:center;background:#173f38;color:#fff;font-family:Georgia,serif;font-size:68px;font-weight:900}.force-mark b,.force-mark i{position:absolute;top:46%;font-size:74px;line-height:1;font-style:normal}.force-mark b{left:7%;color:var(--force-blue)}.force-mark i{right:7%;color:var(--force-orange)}.force-mark small{position:absolute;bottom:18%;padding:7px 12px;border-radius:99px;background:#f0c84b;font-weight:900;letter-spacing:.08em}.force-featured{background:linear-gradient(125deg,#193d62,#315fbd)!important}.force-concept-detail{background:#193d62}.force-quiz-section{background:#e8edf5}.force-lab-section{background:#173f38;color:#fff}.force-lab-section .eyebrow{color:#f3d77d}.force-lab-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.force-lab-grid article{padding:26px;border-radius:20px;background:#fff;color:#173a35}.force-lab-grid small{font-weight:900;letter-spacing:.12em;color:var(--force-blue)}.force-lab-grid h3{font-family:Georgia,serif;font-size:26px;line-height:1.2;margin:8px 0}.force-choice-list{display:grid;gap:8px}.force-choice-list button{padding:11px 13px;border:1px solid #ccd6d4;border-radius:11px;background:#f7f7f3;text-align:left;cursor:pointer}.force-choice-list button.selected{border:2px solid var(--force-blue);background:#e7eefc}.check-force,#checkWeight{margin-top:15px;padding:10px 15px;border:0;border-radius:999px;background:#173f38;color:#fff;font-weight:900;cursor:pointer}.force-case-feedback{min-height:72px;font-weight:800}.weight-section{background:#eef5f7}.weight-lab{display:grid;grid-template-columns:1.1fr 1fr 1fr;gap:18px;align-items:stretch}.weight-input,.planet-card{padding:28px;border-radius:22px;background:#fff}.weight-input label{display:block;font-family:Georgia,serif;font-size:28px;font-weight:900}.weight-input>div{display:grid;grid-template-columns:1fr auto;gap:18px;align-items:center;margin:28px 0}.weight-input input{width:100%;accent-color:var(--force-blue)}.weight-input output{min-width:90px;padding:9px 12px;border-radius:10px;background:#173f38;color:#fff;text-align:center;font-weight:900}.planet-card{display:flex;flex-direction:column;gap:10px;justify-content:center}.planet-card>span{font-size:58px}.planet-card small{font-weight:900;letter-spacing:.12em}.planet-card b{font-size:20px}.planet-card strong{font-size:24px;color:var(--force-blue)}.planet-card.moon{background:#17243e;color:#fff}.planet-card.moon strong{color:#f3d77d}.weight-check{max-width:760px;margin:24px auto 0;padding:28px;border-radius:20px;background:#fff;text-align:center}.weight-check h3{font-family:Georgia,serif;font-size:28px;margin:0}.weight-check input{width:130px;padding:10px;border:1px solid #b9c5c2;border-radius:10px;font:inherit}.weight-check #weightFeedback{min-height:26px;font-weight:900}.friction-section{background:#f7f1e4}.friction-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}.friction-grid article{display:grid;grid-template-columns:auto 1fr;gap:10px 16px;align-items:center;padding:20px;border-radius:18px;background:#fff}.friction-grid article>span{grid-row:1/3;width:40px;height:40px;border-radius:50%;display:grid;place-items:center;background:var(--force-orange);color:#fff;font-weight:900}.friction-grid p{margin:0;font-weight:800}.friction-grid article>div{display:flex;flex-wrap:wrap;gap:7px}.friction-grid button{padding:8px 11px;border:1px solid #ccd6d4;border-radius:999px;background:#f7f7f3;cursor:pointer}.friction-grid button.correct{background:#dcefe1;border-color:#5c9970}.friction-grid button.wrong{background:#fae2da;border-color:#d17b62}.friction-grid small{grid-column:2;min-height:22px;font-weight:800}.misconception-section{background:#dde7f7}.misconception-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.misconception-grid button{min-height:250px;padding:28px;border:0;border-radius:22px;background:#193d62;color:#fff;text-align:left;display:flex;flex-direction:column;cursor:pointer}.misconception-grid button+button{background:#8f3b29}.misconception-grid small{letter-spacing:.12em;font-weight:900;color:#f3d77d}.misconception-grid b{margin:auto 0;font-family:Georgia,serif;font-size:25px;line-height:1.3}.misconception-grid span{display:none;margin-top:18px;line-height:1.55}.misconception-grid button.revealed span{display:block}.misconception-grid button.revealed b{margin:18px 0 0}.force-finish{background:#dbe5f7}
@media(max-width:900px){.force-lab-grid,.weight-lab{grid-template-columns:1fr}.force-mark{max-width:360px;width:75%;margin:auto}}
@media(max-width:700px){.friction-grid,.misconception-grid{grid-template-columns:1fr}}

/* Kafli 1.3 — Frjálst fall */
.fall-hero{background:linear-gradient(135deg,#eaf7ff,#f2efff 62%,#fff5df)}
.fall-mark{width:230px;height:230px;border-radius:50%;background:radial-gradient(circle at 50% 50%,#172844 0 48%,#3e70ad 49% 51%,transparent 52%);position:relative;color:#fff;display:grid;place-items:center;box-shadow:0 28px 60px #1d36542b}
.fall-mark span{position:absolute;top:18px;font-size:2rem;color:#ffad55}.fall-mark i{font-size:5rem;font-style:normal;color:#7ed5ef}.fall-mark b{position:absolute;right:35px;top:85px;font-size:2.6rem}.fall-mark small{position:absolute;bottom:43px;letter-spacing:.1em}
.fall-featured{background:linear-gradient(145deg,#12223b,#254f7b)!important;color:#fff}.fall-featured a{color:#fff}.fall-concept-detail{background:linear-gradient(145deg,#142946,#285b84)}
.fall-case-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.fall-case-grid article{background:#fff;border:1px solid #dce5ee;border-radius:22px;padding:24px;box-shadow:0 12px 30px #1d36540d}.fall-case-grid small{color:#3b7699;font-weight:800;letter-spacing:.1em}.fall-case-grid h3{min-height:58px;margin:8px 0 16px}.fall-case-grid article>div{display:grid;gap:9px}.fall-case-grid button,.orbit-controls button{border:1px solid #b9c9d8;background:#f7fafc;padding:12px 14px;border-radius:12px;text-align:left;font:inherit;font-weight:700;cursor:pointer}.fall-case-grid button:hover,.orbit-controls button:hover{border-color:#397ba3}.fall-case-grid button.correct{background:#dff7e8;border-color:#50a874}.fall-case-grid button.wrong{background:#fff0ed;border-color:#d66a5d}.fall-case-grid article>p{min-height:76px;line-height:1.5}.fall-case-grid p.good{color:#167044}.fall-case-grid p.try{color:#a53f34}
.orbit-lab{display:grid;grid-template-columns:1.4fr 1fr;gap:26px;align-items:center;background:#eef7fb;border-radius:28px;padding:28px}.orbit-stage{height:330px;position:relative;overflow:hidden;border-radius:22px;background:linear-gradient(#12213f 0 58%,#8fd4ee 59%)}.orbit-earth{position:absolute;width:500px;height:500px;border-radius:50%;background:radial-gradient(circle at 45% 20%,#82c9a8,#367eb0 55%,#154b79);left:50%;transform:translateX(-50%);top:205px;color:#fff;text-align:center;padding-top:45px;font-weight:900;letter-spacing:.18em}.orbit-path{position:absolute;left:20%;top:65px;width:60%;height:180px;border-top:5px dashed #ffb55d;border-radius:50%;transform:rotate(18deg);transition:.35s}.orbit-path span{display:block;width:18px;height:18px;border-radius:50%;background:#ff765f;box-shadow:0 0 18px #ff765f;position:absolute;left:3%;top:-11px}.orbit-path.langt{width:78%;height:220px;left:12%;transform:rotate(8deg)}.orbit-path.braut{width:86%;height:260px;left:7%;top:38px;border:5px dashed #ffb55d;transform:none}.orbit-controls{display:grid;gap:10px}.orbit-controls button{text-align:center}.orbit-controls button.active{background:#214f76;color:#fff;border-color:#214f76}.orbit-controls p{min-height:90px;line-height:1.55;font-weight:650}
@media(max-width:800px){.fall-case-grid,.orbit-lab{grid-template-columns:1fr}.fall-mark{width:180px;height:180px}.orbit-stage{height:280px}.fall-case-grid h3{min-height:0}}

/* Gagnvirkar æfingar og hugtakalisti */
.exercise-section{max-width:920px;margin:auto}.exercise-section h1{font-family:Georgia,serif;font-size:clamp(2rem,5vw,3.5rem)}.exercise-input{display:block;width:100%;max-width:560px;padding:14px;margin:10px 0 24px;border:1px solid #a9bcb5;border-radius:12px;background:#fff;color:#173f38;font:inherit}.exercise-card{padding:clamp(20px,4vw,40px);border:1px solid #d7e3dd;border-radius:24px;background:#fff;box-shadow:0 14px 38px #173f380d}.exercise-status{display:flex;justify-content:space-between;gap:12px;font-weight:700;flex-wrap:wrap}.exercise-card progress{width:100%;height:10px;margin:16px 0;accent-color:#276e52}.exercise-question{font-size:1.25rem;line-height:1.6}.exercise-choice{display:flex;align-items:center;gap:14px;padding:16px;border:2px solid #d7e3dd;border-radius:12px;cursor:pointer;background:#fafbf7}.exercise-choice:has(input:checked){border-color:#276e52;background:#edf6ee}.exercise-choice input{width:20px;height:20px;flex-shrink:0;accent-color:#276e52}.exercise-choice.correct{background:#e4f3e8;border-color:#2f7850}.exercise-choice.incorrect{background:#fff0e9;border-color:#b45a39}.exercise-card .answers{display:grid;gap:12px;margin-bottom:22px}.exercise-feedback{line-height:1.6;margin:20px 0}.exercise-feedback.ok{border-left:4px solid #276e52;padding:14px;background:#edf6ee}.exercise-feedback.no{border-left:4px solid #b45a39;padding:14px;background:#fff3eb}.exercise-card button:disabled{opacity:.7}.glossary-section{background:#edf3ed}.term-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;padding:0}.term-list>div{padding:22px;background:#fff;border-radius:16px}.term-list dt{font-weight:800;font-size:1.1rem;color:#173f38}.term-list dd{margin:9px 0 0;line-height:1.6}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #dc9d25;outline-offset:4px}@media(max-width:650px){.term-list{grid-template-columns:1fr}.exercise-section{padding:24px 16px}.exercise-card{padding:20px}.exercise-choice{padding:12px}}

/* Samræmt við kafla 1.2: flettilisti, hugtakaspjald og æfingaspjöld. */
.concept-scroll{max-height:430px;overflow-y:auto;align-content:start;padding:3px 8px 3px 3px}.concept-scroll button{font-weight:800;font-size:16px;min-height:60px}.glossary-section .motion-concept-detail{align-self:start;position:sticky;top:100px}.motion-chapter-hero h1#chapterHeading{font-size:clamp(48px,6.5vw,94px);overflow-wrap:normal}.motion-quiz-grid .exercise-input,.calculation-grid .exercise-input{width:100%;max-width:100%;margin:12px 0}.motion-quiz-grid form button{padding:10px 16px;border:0;border-radius:99px;background:#173f38;color:#fff;font:inherit;font-weight:800;cursor:pointer}.glossary-section select{max-width:560px}.calculation-grid .quiz-feedback{color:#173a35}.calculation-grid .quiz-feedback.good{color:#39744b}.calculation-grid .quiz-feedback.try{color:#a14f39}@media(max-width:900px){.glossary-section .motion-concept-detail{position:static}.concept-scroll{max-height:260px}}