.home-world{position:relative;overflow:hidden;background:radial-gradient(ellipse at 50% 12%,#fff 10%,#e7f6ff 60%,#fff9ec);padding-top:var(--header-h)}.home-world .rail{position:absolute;top:var(--header-h);width:27%;height:auto;z-index:0}.home-world .rail.left{left:0}.home-world .rail.right{right:0}.home-copy{position:relative;z-index:1;text-align:center;width:min(560px,65%);margin:auto;padding:32px 0 12px}.home-copy h1{font-size:clamp(35px,4.55vw,62px);letter-spacing:-.047em;margin-bottom:14px}.home-copy h1 span{display:table;margin:5px auto 0;color:var(--teal);background:linear-gradient(90deg,transparent,#d5f3ff 12%,#d5f3ff 88%,transparent);padding:0 25px 4px;border-radius:999px}.home-copy p{font-size:clamp(13px,1.15vw,16px);max-width:530px;margin:0 auto 14px}.home-copy .caption{margin-top:8px;font-size:11px}.home-scene{position:relative;z-index:1;width:100%;display:block;mix-blend-mode:normal}.activity-grid{display:grid;grid-template-columns:repeat(12,1fr);gap:14px}.activity-card{grid-column:span 3;display:flex;flex-direction:column;position:relative;overflow:hidden;min-height:210px;border:1px solid var(--line);border-radius:16px;background:linear-gradient(118deg,#fff 50%,#fff8e9);box-shadow:var(--shadow-card);text-decoration:none;color:var(--ink);padding:16px 19px 0;transition:transform 180ms,box-shadow 180ms}.activity-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-panel);color:var(--ink)}.activity-card:nth-child(n+5){grid-column:span 4;min-height:180px}.activity-card h3{font-size:17px;margin:7px 0 4px;line-height:1.2}.activity-card p{font-size:12px;line-height:1.45;margin:0 28px 5px 0}.activity-card .arrow{position:absolute;top:15px;right:15px;width:31px;height:31px;border-radius:50%;background:#fff;display:grid;place-items:center;box-shadow:0 2px 7px #1824420d}.activity-card .arrow .icon{width:17px;height:17px}.activity-card .art{width:100%;margin-top:auto;max-height:123px;object-fit:cover;object-position:bottom;mix-blend-mode:multiply}.activity-card .source-icon{width:35px;height:35px;object-fit:contain;mix-blend-mode:multiply}.activity-card .state{padding:10px 0;font-size:12px}.activity-card:nth-child(n+5) .art{max-height:100px}.home-features{padding-top:25px;background:linear-gradient(#fff,#fbfdff)}.auth-world{position:relative;overflow:hidden;background:radial-gradient(ellipse at 50% 20%,#fff 20%,#eef9ff 70%,#fff6e5);min-height:850px;padding:105px 0 55px}.auth-world .art-rail{position:absolute;top:var(--header-h);height:calc(100% - var(--header-h));width:31%;object-fit:cover;object-position:top;z-index:0}.auth-world .art-rail.left{left:0;object-position:left top}.auth-world .art-rail.right{right:0;object-position:right top}.auth-world::after{content:'';position:absolute;bottom:0;left:0;right:0;height:80px;background:linear-gradient(transparent,#fff);pointer-events:none}.auth-heading{text-align:center;position:relative;z-index:2;max-width:650px;margin:0 auto 24px;padding:0 24px}.auth-heading h1{font-size:clamp(37px,4.15vw,56px)}.auth-heading p{font-size:15px;margin-bottom:0}.auth-card{position:relative;z-index:2;width:min(430px,calc(100% - 40px));padding:32px;border:1px solid #e5eaf1;border-radius:26px;background:#fff;box-shadow:var(--shadow-panel);margin:0 auto}.auth-card .icon-top{margin:0 auto 18px;display:grid;place-items:center;width:74px;height:74px;background:var(--sky);border-radius:23px;color:var(--blue)}.auth-card .icon-top .icon{width:40px;height:40px}.auth-card .foot-link{font-size:12px;text-align:center;margin:0}.auth-card .product-summary{display:flex;align-items:center;gap:18px;padding:18px;background:var(--sky-soft);border-radius:16px;margin-bottom:22px}.mini-cover{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;width:94px;height:122px;flex-shrink:0;background:linear-gradient(#d9f3ff 8%,#fff9ed 78%);border-radius:3px 8px 8px 3px;border-left:7px solid #288bc3;box-shadow:3px 5px 8px #18304c26;padding:10px;color:var(--ink);position:relative;overflow:hidden}.mini-cover .icon{width:35px;height:35px;color:#218943;margin-top:6px}.mini-cover strong{font:750 17px/1.1 var(--font-heading)}.mini-cover small{font-size:10px}.stepper{display:flex;justify-content:space-between;gap:8px;margin:0 0 24px;text-align:center}.stepper>div{flex:1;position:relative;font-size:11px;color:var(--text)}.stepper span{display:grid;place-items:center;width:30px;height:30px;margin:0 auto 5px;border:1px solid #cbd8e6;border-radius:50%;background:#fff;color:var(--text)}.stepper .active span{background:var(--blue);color:#fff;border-color:var(--blue)}.otp-input{font:600 31px/1.1 var(--font-body)!important;text-align:center;letter-spacing:.42em;padding:18px 8px!important;min-height:72px!important}.auth-split .auth-card{margin-left:53%;width:min(420px,42%)}.auth-split .auth-heading{text-align:left;margin-left:15%;max-width:70%;padding:0}.auth-split .auth-heading h1{font-size:47px}.screen-world{position:relative;padding-top:calc(var(--header-h) + 35px);min-height:600px;background:linear-gradient(#f1faff,#fff 520px);overflow:hidden}.screen-world::before,.screen-world::after{content:'';position:absolute;top:var(--header-h);width:23%;height:490px;background-size:cover;pointer-events:none;opacity:.88}.screen-world::before{left:0;background-image:url('../art/auth-left.png');background-position:left top;mask-image:linear-gradient(90deg,#000 30%,transparent)}.screen-world::after{right:0;background-image:url('../art/auth-right.png');background-position:right top;mask-image:linear-gradient(270deg,#000 30%,transparent)}.screen-world>.container{position:relative;z-index:1}.page-intro{text-align:center;margin:24px auto 36px;max-width:760px}.page-intro p{font-size:16px}.page-intro .source-icon{width:43px;height:43px;mix-blend-mode:multiply}.unit-progress{display:flex;gap:18px;align-items:center;padding:14px 20px;border:1px solid var(--line);background:#fff;border-radius:999px;max-width:450px;margin:22px auto;color:var(--ink);font-size:13px}.unit-progress .progress-track{flex:1}.unit-grid{margin-top:42px}.unit-grid .activity-card{grid-column:span 4;min-height:265px}.unit-grid .activity-card:nth-child(7){grid-column:span 12;min-height:145px;display:block;padding:24px 28px}.unit-grid .activity-card:nth-child(7) .art{position:absolute;right:100px;bottom:0;width:280px;height:125px}.unit-grid .activity-card:nth-child(7) .state{position:relative;z-index:1}.unit-grid .activity-card:nth-child(7) h3{margin-top:0}.unit-grid .activity-card:nth-child(7) .source-icon{float:left;margin-right:20px;width:48px;height:48px}.book-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.book-card{display:flex;align-items:center;gap:24px;min-height:220px}.book-card .mini-cover{width:114px;height:157px}.add-book{display:flex;align-items:center;justify-content:center;flex-direction:column;border:1px dashed #b8cbdc;min-height:220px;color:var(--ink);text-decoration:none}.add-book .badge-circle{margin-bottom:10px}.continue-card{display:grid;grid-template-columns:28% 1fr 29%;gap:26px;margin-top:25px;align-items:center}.continue-card>img{width:100%;height:190px;object-fit:cover;border-radius:13px}.checklist{list-style:none;padding:0;margin:0;font-size:12px}.checklist li{padding:5px 0;display:flex;gap:9px;align-items:center}.checklist .icon{width:18px;height:18px;color:var(--green)}.inline-progress{display:flex;gap:15px;align-items:center;margin:17px 0;font-size:12px}.inline-progress .progress-track{flex:1}.unit-library{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}.unit-tile{color:var(--ink);text-decoration:none;padding:24px;min-height:230px}.unit-tile .unit-art{width:76px;height:76px;border-radius:22px;background:linear-gradient(130deg,#f2fcf7,#fff6dc);display:grid;place-items:center;margin:0 auto 16px;color:var(--green)}.unit-tile .unit-art .icon{width:46px;height:46px}.unit-tile h3{font-size:20px}.unit-tile .pill{margin-top:12px}.utility-layout{display:grid;grid-template-columns:235px 1fr;gap:25px}.utility-nav{display:flex;flex-direction:column;gap:6px;align-self:start}.utility-nav a{color:var(--text);display:flex;align-items:center;gap:13px;padding:13px;border-radius:12px;font-size:14px;text-decoration:none}.utility-nav a.active{background:var(--sky);color:var(--blue)}.legal-copy h2{font-size:23px;margin-top:30px}.legal-copy p,.legal-copy li{color:var(--text);font-size:15px;line-height:1.75}.metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-bottom:24px}.metric .value{font:750 43px/1.1 var(--font-heading);display:block;margin:12px 0;color:var(--blue)}.score-ring{--score:0;display:grid;place-items:center;width:180px;height:180px;border-radius:50%;background:conic-gradient(#27ab69 calc(var(--score)*1%),#e7eef5 0);margin:0 auto 22px;position:relative}.score-ring::before{content:'';position:absolute;inset:14px;border-radius:50%;background:white}.score-ring span{position:relative;font:750 35px/1 var(--font-heading)}.review-item{padding:18px 0;border-top:1px solid var(--line)}.review-item .answer-status{font-weight:650;font-size:13px}.result-actions{display:flex;gap:14px;flex-wrap:wrap;justify-content:center;margin-top:24px}.result-card{max-width:700px;margin:0 auto}.completion-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:25px 0}.completion-row{padding:12px;background:var(--sky-soft);border-radius:10px;display:flex;gap:10px;align-items:center;font-size:13px}.screen-index{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.screen-link{display:block;padding:20px;color:var(--ink);text-decoration:none}.screen-link strong{display:block}.screen-link small{color:var(--text)}.invitation-output{margin-top:16px;padding:16px;background:var(--sky-soft);border-radius:12px;overflow-wrap:anywhere;font-size:13px}
/* Explicit typography specificity and provisional crop seam treatment. */
.auth-heading .eyebrow,.page-intro .eyebrow{font-size:10px;letter-spacing:.3em;margin-bottom:14px}
.home-world .rail{height:calc(100% - var(--header-h) - 37.725vw);object-fit:cover;object-position:bottom}
.world-banner img{mask-image:linear-gradient(90deg,transparent,#000 12%)}

/* Unit Lab: B2-01 hierarchy, composed from the supplied provisional art layers. */
.unit-lab{background:var(--sky-soft)}
.unit-hero{position:relative;isolation:isolate;min-height:535px;padding:calc(var(--header-h) + 28px) 0 100px;background:linear-gradient(180deg,var(--sky),var(--paper) 68%,var(--cream));overflow:hidden}
.unit-hero::before,.unit-hero::after{content:"";position:absolute;z-index:-1;top:var(--header-h);bottom:0;width:27%;background-size:cover;pointer-events:none}
.unit-hero::before{left:0;background-image:url('../art/auth-left.png');background-position:left center;mask-image:linear-gradient(90deg,#000 40%,transparent)}
.unit-hero::after{right:0;background-image:url('../art/auth-right.png');background-position:right center;mask-image:linear-gradient(270deg,#000 45%,transparent)}
.unit-hero .breadcrumbs{justify-content:center;margin-bottom:24px}
.unit-hero .container{position:relative;z-index:2}
.unit-heading{max-width:680px;margin:auto;text-align:center}
.unit-heading h1{font-size:clamp(38px,4.8vw,60px);line-height:1.1;margin:0 0 16px}
.unit-number{display:block;margin-bottom:4px;color:var(--ink)}
.unit-heading>p{font-size:16px;max-width:490px;margin:0 auto}
.unit-heading .unit-choice{font-size:12px;max-width:340px}
.unit-heading .unit-progress{max-width:370px;margin:22px auto 14px;padding:12px 20px;gap:24px;box-shadow:var(--shadow-card)}
.unit-heading .progress-track{height:16px}
.unit-progress>span{white-space:nowrap;color:var(--text);font-size:12px}
.unit-progress strong{color:var(--ink)}
.unit-robot{position:absolute;z-index:1;left:max(16px,calc((100% - 1280px)/2));bottom:0;width:220px;height:280px;object-fit:cover;object-position:top;pointer-events:none;mask-image:linear-gradient(180deg,transparent,#000 10%,#000 85%,transparent);border-radius:var(--radius-xl)}
.unit-activities{position:relative;margin-top:0;padding-bottom:8px}
.unit-lab .unit-grid{margin-top:0;gap:14px}
.unit-lab .activity-card{display:block;grid-column:span 4;min-height:240px;padding:20px 20px 132px;border-radius:var(--radius-lg)}
.unit-lab .activity-card .source-icon{position:absolute;top:21px;left:20px;width:46px;height:46px;max-width:none}
.unit-lab .activity-copy{margin-left:68px}
.unit-lab .activity-card h3{font-size:18px;margin:0 24px 4px 0;line-height:1.2;max-width:none}
.unit-lab .activity-card p{max-width:none;margin:0 0 8px;font-size:13px}
.unit-lab .activity-card .activity-subtitle{color:var(--blue-deep);font-size:15px;text-transform:capitalize}
.unit-lab .activity-card .activity-description{line-height:1.35}
.unit-lab .activity-card .arrow{top:16px;right:12px;width:30px;height:30px}
.unit-lab .activity-card .art{position:absolute;bottom:0;left:0;right:auto;width:100%;height:125px;max-width:none;max-height:none;object-fit:cover;object-position:center 65%;margin:0;mask-image:linear-gradient(180deg,transparent,#000 22%)}
.unit-lab .activity-card .state:not(.sr-only){position:absolute;bottom:12px;left:18px;z-index:2;padding:0}
.unit-lab .activity-card .pill{border:1px solid var(--line);background:var(--paper)}
.unit-lab .activity-card .pill.success{background:var(--green-bg)}
.unit-lab .activity-card:nth-child(7){min-height:126px;padding:24px 28px;grid-column:1/-1}
.unit-lab .activity-card:nth-child(7) .source-icon{float:none;top:25px;left:28px;margin:0;width:48px;height:48px}
.unit-lab .activity-card:nth-child(7) .activity-copy{max-width:54%;margin-left:84px;position:relative;z-index:1}
.unit-lab .activity-card:nth-child(7) h3{font-size:24px}
.unit-lab .activity-card:nth-child(7) .art{left:auto;right:65px;width:34%;height:126px;mask-image:linear-gradient(90deg,transparent,#000 20%)}
.unit-lab .activity-card:nth-child(7) .state:not(.sr-only){left:auto;right:60px;bottom:12px}
.unit-lab .world-banner{margin-top:16px}
.workspace-intro{text-align:left;max-width:none}
.workspace-intro h1{font-size:clamp(32px,4vw,48px);overflow-wrap:anywhere}
.workspace-section-title{margin-top:36px}
.book-card h2,.add-book h2,.progress-unit h2{font-size:23px}
.progress-unit{margin-bottom:24px}.progress-unit>.btn{margin-top:20px}
.unit-lab .activity-card .state.sr-only{position:absolute}
.member-action{display:flex;align-items:center;gap:8px;flex-wrap:wrap;max-width:280px}
.member-action select{max-width:100%;min-height:44px;border:1px solid var(--line);border-radius:var(--radius-sm);padding:8px;background:var(--paper);color:var(--ink)}
.member-action .form-status{flex-basis:100%;margin:0}

/* Keep each supplied activity artwork with its original card geometry. */
.home-features .activity-card--compact{grid-column:span 3;min-height:210px}
.home-features .activity-card--wide{grid-column:span 4;min-height:180px}
.home-features .activity-card .art{width:100%;height:auto;max-width:100%;object-fit:contain;object-position:center bottom}
.home-features .activity-card--compact .art{max-height:123px}
.home-features .activity-card--wide .art{max-height:100px}
.unit-lab .activity-card--standard{grid-column:span 4;min-height:240px}
.unit-lab .activity-card--featured{grid-column:1/-1;min-height:126px;padding:24px 28px}
.unit-lab .activity-card .art{object-fit:contain;object-position:center bottom;mask-image:none}
.unit-lab .activity-card--featured .source-icon{top:25px;left:28px;width:48px;height:48px}
.unit-lab .activity-card--featured .activity-copy{max-width:54%;margin-left:84px;position:relative;z-index:1}
.unit-lab .activity-card--featured h3{font-size:24px}
.unit-lab .activity-card--featured .art{left:auto;right:65px;width:34%;height:126px;object-fit:contain;mask-image:none}

/* Licensed Ringlet chapter content inside Knowledge Lab. */
.unit-lab .unit-hero{min-height:0;padding-bottom:54px}
.chapter-picker{position:relative;display:grid;grid-template-columns:minmax(225px,.48fr) minmax(0,1fr);align-items:center;gap:22px;width:min(100%,880px);margin:28px auto 0;padding:18px 20px;overflow:hidden;border:1px solid rgba(92,177,216,.58);border-radius:22px;background:linear-gradient(120deg,rgba(255,255,255,.98),rgba(232,248,255,.96));box-shadow:0 16px 38px rgba(22,88,124,.13),inset 0 1px 0 #fff}
.chapter-picker::before{content:'';position:absolute;right:-45px;top:-70px;width:180px;height:180px;border-radius:50%;background:radial-gradient(circle,rgba(72,191,224,.18),transparent 68%);pointer-events:none}
.chapter-picker-label{position:relative;z-index:1;display:flex;align-items:center;gap:12px;min-width:0;text-align:left}.chapter-picker-label>span:last-child{min-width:0}.chapter-picker-label strong,.chapter-picker-label small{display:block}.chapter-picker-label strong{color:var(--ink);font-size:17px}.chapter-picker-label small{margin-top:3px;color:var(--text);font-size:12px;line-height:1.35}
.chapter-picker-icon{display:grid;place-items:center;flex:0 0 46px;height:46px;border-radius:14px;background:linear-gradient(145deg,var(--blue),#23a8d5);box-shadow:0 7px 16px rgba(0,111,180,.2);color:#fff}.chapter-picker-icon .icon{width:25px;height:25px}
.chapter-picker-control{position:relative;z-index:1;min-width:0}
.chapter-picker select{appearance:none;display:block;width:100%;min-width:0;height:54px;padding:0 54px 0 17px;border:1px solid #add2e5;border-radius:15px;background:rgba(255,255,255,.98);color:var(--ink);font-size:14px;font-weight:650;text-overflow:ellipsis;box-shadow:0 6px 16px rgba(18,82,116,.08),inset 0 1px 1px rgba(16,59,82,.03);cursor:pointer;transition:border-color var(--duration-fast),box-shadow var(--duration-fast),transform var(--duration-fast)}
.chapter-picker select:hover{border-color:#55b2dc;box-shadow:0 8px 20px rgba(18,82,116,.12)}.chapter-picker select:focus-visible{border-color:var(--blue);box-shadow:var(--focus),0 8px 20px rgba(18,82,116,.12)}
.chapter-picker-chevron{position:absolute;right:19px;top:50%;width:11px;height:11px;border-right:2px solid var(--blue);border-bottom:2px solid var(--blue);transform:translateY(-70%) rotate(45deg);pointer-events:none;transition:transform var(--duration-fast)}
.chapter-picker:focus-within .chapter-picker-chevron{transform:translateY(-30%) rotate(225deg)}
.chapter-picker.is-loading{opacity:.72;pointer-events:none}.chapter-picker.is-loading .chapter-picker-chevron{width:18px;height:18px;border:2px solid var(--blue);border-right-color:transparent;border-radius:50%;animation:spin .7s linear infinite;transform:none;top:18px;right:17px}
.chapter-empty{display:flex;justify-content:center;gap:8px;flex-wrap:wrap;margin:28px auto 0;padding:14px 18px;border:1px solid var(--line);border-radius:15px;background:rgba(255,255,255,.86);color:var(--text);font-size:13px}.chapter-empty strong{color:var(--ink)}
.selected-chapter{display:flex;align-items:baseline;gap:10px;margin:20px 0 14px;color:var(--text);font-size:12px}.selected-chapter strong{color:var(--ink);font-size:17px}
.unit-lab .activity-card.is-unavailable{cursor:default;filter:saturate(.55);opacity:.72}.unit-lab .activity-card.is-unavailable:hover{transform:none;box-shadow:var(--shadow-card)}
.knowledge-content-world{padding-bottom:58px;background:linear-gradient(180deg,#eefaff,#fff 520px)}
.knowledge-content-world>.container{max-width:980px}
.content-heading{text-align:center;max-width:720px;margin:12px auto 26px}.content-heading h1{font-size:clamp(32px,4vw,52px)}.content-heading>p:last-child{font-size:15px}
.content-panel{padding:28px;border:1px solid var(--line);border-radius:22px;background:rgba(255,255,255,.98);box-shadow:var(--shadow-card)}
.video-stage{padding:12px;background:#10243a}.video-stage video{display:block;width:100%;max-height:70vh;border-radius:13px;background:#07121f}
.content-actions{display:flex;justify-content:center;margin-top:24px}
.question-bank-list{display:grid;gap:18px}.question-bank-card{position:relative}.question-number{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:15px;color:var(--blue);font-size:13px;font-weight:750;text-transform:uppercase;letter-spacing:.08em}.question-number span{padding:5px 9px;border-radius:999px;background:var(--sky-soft);color:var(--text);font-size:10px;letter-spacing:0}.question-bank-card h2{font-size:clamp(19px,2.1vw,27px);line-height:1.4;margin-bottom:18px;letter-spacing:-.015em}.question-passage{margin:0 0 18px;padding:16px;border-left:4px solid var(--cyan);border-radius:0 12px 12px 0;background:var(--sky-soft);color:var(--text);font-size:14px}.question-media{display:block;max-width:min(100%,520px);max-height:360px;margin:14px 0 20px;border:1px solid var(--line);border-radius:13px;object-fit:contain}.question-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:0;padding:0;list-style-position:inside}.question-options li{min-height:54px;padding:13px;border:1px solid var(--line);border-radius:12px;background:#fbfdff;color:var(--ink)}.question-options li::marker{color:var(--blue);font-weight:750}.question-options img{display:block;max-width:220px;max-height:180px;margin:10px auto 0;object-fit:contain}.question-answer{margin-top:18px;border-top:1px solid var(--line)}.question-answer summary{color:var(--green)}.question-answer div{padding:12px 15px;border-radius:11px;background:var(--green-bg)}.question-answer p:last-child{margin-bottom:0}

/* School library and restricted platform administration. */
.site-messages{position:fixed;z-index:90;top:calc(var(--header-h) + 12px);right:24px;display:grid;gap:8px;width:min(390px,calc(100% - 32px))}.site-message{padding:13px 16px;border:1px solid #afdac0;border-radius:13px;background:#f0fff5;box-shadow:var(--shadow-panel);color:#17613d;font-size:13px;font-weight:600}.site-message.info{border-color:#b4d8ea;background:#f0faff;color:#155b7c}.site-message.error{border-color:#e9b4bb;background:var(--red-bg);color:var(--red)}
.library-heading,.platform-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;margin:16px 0 30px}.library-heading h1,.platform-heading h1{font-size:clamp(34px,4.4vw,56px);overflow-wrap:anywhere}.library-heading p,.platform-heading p{margin-bottom:0}.library-add-panel{display:grid;grid-template-columns:minmax(250px,.8fr) minmax(360px,1.2fr);align-items:center;gap:30px;margin-bottom:38px;background:linear-gradient(125deg,#fff 20%,#edfaff);border-color:#c8e4f2}.library-add-copy{display:flex;align-items:center;gap:15px}.library-add-copy .badge-circle{flex:0 0 54px;margin:0}.library-add-copy h2{font-size:24px;margin-bottom:5px}.library-add-copy p{margin:0}.library-isbn-form label{display:block;margin-bottom:7px;color:var(--ink);font-size:13px;font-weight:700}.library-isbn-control{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:10px}.library-isbn-control input{width:100%;min-width:0;min-height:48px;padding:11px 14px;border:1px solid #b9ccda;border-radius:12px;background:#fff}.library-isbn-control .btn{white-space:nowrap}.library-section-heading{display:flex;align-items:end;justify-content:space-between;gap:20px;margin:0 0 18px}.library-section-heading h2{margin:0}.library-section-heading .eyebrow{margin-bottom:7px}.library-count{padding:7px 12px;border-radius:999px;background:var(--sky-soft);color:var(--blue);font-size:12px;font-weight:700}.library-book-grid{margin-bottom:32px}.library-book-grid .book-card{position:relative}.book-isbn{color:var(--muted);font-size:11px}.library-empty{grid-column:1/-1}.library-empty .badge-circle{margin-inline:auto}
.platform-school-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.platform-school-card{display:block;color:var(--ink);text-decoration:none;transition:transform var(--duration-fast),box-shadow var(--duration-fast)}.platform-school-card:hover{color:var(--ink);transform:translateY(-3px);box-shadow:var(--shadow-panel)}.platform-school-top{display:flex;align-items:start;justify-content:space-between}.platform-school-card h2{font-size:23px;margin:5px 0}.platform-school-card>p{font-size:13px}.platform-school-card dl{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:20px 0}.platform-school-card dl div{padding:11px;border-radius:11px;background:var(--sky-soft)}.platform-school-card dt{color:var(--muted);font-size:10px;text-transform:uppercase;letter-spacing:.08em}.platform-school-card dd{margin:3px 0 0;color:var(--ink);font-size:13px;font-weight:750;overflow-wrap:anywhere}.platform-card-link{color:var(--blue);font-size:13px;font-weight:700}.platform-signout{margin-top:30px}.platform-form-panel{padding:34px}.platform-form-grid{display:grid;grid-template-columns:1fr 1fr;gap:4px 20px}.platform-form-grid .field-wide{grid-column:1/-1}.platform-form-grid .field input{width:100%;min-height:49px;padding:12px 14px;border:1px solid #ccd6e4;border-radius:11px;background:#fff}.platform-form-grid .field label{display:block;margin-bottom:7px;color:var(--ink);font-size:13px;font-weight:700}.platform-form-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:14px}.school-detail-heading{align-items:center}.credential-card{min-width:275px;padding:17px 20px;border:1px solid #b8dcea;border-radius:17px;background:linear-gradient(135deg,#fff,#eaf9ff);box-shadow:var(--shadow-card)}.credential-card span,.credential-card small{display:block}.credential-card span{color:var(--muted);font-size:10px;text-transform:uppercase;letter-spacing:.1em}.credential-card strong{display:block;margin:4px 0;color:var(--blue);font-size:22px;letter-spacing:.04em}.credential-card small{color:var(--text);font-size:10px}.admin-book-list{display:grid;gap:12px}.admin-book-row{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:20px 24px}.admin-book-row h3{margin:9px 0 4px}.admin-book-row p{margin:0;font-size:12px}.admin-library-add{margin-top:4px}

/* Keep the school library separate from the decorative page scene. */
.library-page .screen-world{padding-bottom:64px;background:linear-gradient(180deg,#eef9ff 0,#f8fcff 330px,#f4f8fb 100%);overflow:visible}
.library-page .screen-world::before,.library-page .screen-world::after{opacity:.16;filter:saturate(.65)}
.library-page .screen-world>.container{width:min(calc(100% - 64px),1180px)}
.library-books-shell{position:relative;padding:28px;border:1px solid rgba(190,211,225,.88);border-radius:28px;background:rgba(255,255,255,.94);box-shadow:0 20px 48px rgba(25,75,105,.1);isolation:isolate}
.library-books-shell::before{content:'';position:absolute;z-index:-1;inset:0;border-radius:inherit;background:linear-gradient(135deg,rgba(229,247,255,.45),transparent 38%,rgba(255,248,229,.38))}
.library-book-grid{grid-template-columns:repeat(2,minmax(0,1fr));align-items:stretch;margin:0}
.library-book-grid .library-book-card{display:grid;grid-template-columns:122px minmax(0,1fr);align-items:center;gap:24px;min-width:0;min-height:218px;padding:26px;overflow:hidden;border-color:#dce9f1;background:linear-gradient(125deg,#fff 45%,#f5fbff);box-shadow:0 9px 24px rgba(29,78,106,.08)}
.library-book-grid .library-book-card:hover{border-color:#b7dbea;box-shadow:0 14px 30px rgba(29,78,106,.12)}
.library-book-grid .library-book-card .mini-cover{width:122px;height:165px;max-width:100%;margin:0}
.mini-cover.has-cover{padding:4px;border-left:0;border-radius:10px;background:#fff;box-shadow:0 8px 20px rgba(18,54,74,.16),inset 0 0 0 1px rgba(151,188,207,.32)}
.mini-cover.has-cover img{display:block;width:100%;height:100%;border-radius:7px;object-fit:contain;object-position:center;background:#fff}
.library-book-copy{display:flex;align-items:flex-start;flex-direction:column;min-width:0;height:100%;padding:4px 0}
.library-book-copy .eyebrow{margin-bottom:8px}.library-book-copy h2{width:100%;margin-bottom:8px;font-size:22px;overflow-wrap:anywhere}.library-book-copy .publisher-name{width:100%;margin-bottom:5px;overflow-wrap:anywhere}.library-book-copy .book-isbn{width:100%;margin-bottom:15px;overflow-wrap:anywhere}.library-book-copy .btn{margin-top:auto}

/* Reserve a stable row for hero copy so it never moves into the scene artwork. */
.home-world{display:grid;grid-template-rows:clamp(300px,25vw,350px) auto}
.home-copy{grid-row:1;align-self:center;max-height:100%;padding:20px 0;transform:scale(.9);transform-origin:center center}
.home-scene{grid-row:2;margin:0}

/* Overlap the hero art layers to prevent browser-zoom rounding seams. */
.home-world .rail{display:block;height:calc(100% - var(--header-h) - 37.725vw + 6px)}
.home-scene{top:-6px;margin-bottom:-6px}

/* Use one clean home-world backdrop everywhere; page content never shares its layer with artwork. */
.auth-world,.screen-world,.unit-hero,.knowledge-content-world,.library-page .screen-world,.platform-page .screen-world{background:radial-gradient(ellipse at 50% 12%,#fff 8%,#e7f6ff 58%,#fff9ec 100%)}
.auth-world .art-rail,.auth-world::before,.screen-world::before,.screen-world::after,.unit-hero::before,.unit-hero::after,.unit-robot{display:none}
.auth-world>*,.screen-world>.container,.unit-hero>.container{position:relative;z-index:1}
.nav-signout{display:flex;margin:0}.nav-signout .btn{white-space:nowrap}.nav-signout .icon{width:18px;height:18px}

/* Content pages use the home classroom as the card backdrop. */
body:not(.home-page):not(.auth-page) main{background:linear-gradient(180deg,rgba(241,250,255,.62),rgba(255,255,255,.48),rgba(255,249,236,.58)),url('../art/home-scene.webp') center center/cover fixed no-repeat}
body:not(.home-page):not(.auth-page) .screen-world,body:not(.home-page):not(.auth-page) .unit-hero,body:not(.home-page):not(.auth-page) .knowledge-content-world,body.library-page .screen-world,body.platform-page .screen-world{background:linear-gradient(180deg,rgba(247,252,255,.5),rgba(255,255,255,.24))}
body:not(.home-page):not(.auth-page) .unit-activities{padding-top:22px;padding-bottom:50px}

/* Keep the book activity picker calm and easy to scan. */
body.unit-lab:not(.home-page):not(.auth-page) main{
  background:
    radial-gradient(circle at 9% 18%,rgba(115,199,232,.13) 0 70px,transparent 71px),
    radial-gradient(circle at 91% 42%,rgba(255,211,98,.12) 0 95px,transparent 96px),
    radial-gradient(circle at 20% 82%,rgba(109,197,143,.1) 0 80px,transparent 81px),
    linear-gradient(180deg,#eef9ff 0,#f8fcff 42%,#fffdf5 100%)
}
body.unit-lab:not(.home-page):not(.auth-page) .unit-hero{
  background:linear-gradient(180deg,rgba(255,255,255,.68),rgba(255,255,255,.3))
}
body.unit-lab .unit-activities{position:relative;z-index:1}
.unit-lab .unit-hero{padding-bottom:46px}
.unit-lab .unit-hero .breadcrumbs{justify-content:flex-start;width:min(100%,1050px);margin:0 auto 18px}
.book-overview{display:grid;grid-template-columns:190px minmax(0,1fr);align-items:center;gap:34px;width:min(100%,1050px);margin:0 auto;padding:28px;border:1px solid rgba(174,207,224,.72);border-radius:30px;background:rgba(255,255,255,.82);box-shadow:0 18px 48px rgba(32,88,118,.1);backdrop-filter:blur(8px)}
.book-cover-stage{display:grid;place-items:center;align-self:start;min-width:0;margin:0;padding:10px;border-radius:20px;background:linear-gradient(145deg,#e9f7ff,#fff9e9);box-shadow:inset 0 0 0 1px rgba(133,190,217,.3)}
.book-cover-stage>img{display:block;width:100%;height:240px;border-radius:11px;object-fit:contain;filter:drop-shadow(0 9px 10px rgba(18,54,74,.18))}
.book-cover-fallback{display:flex;width:100%;height:240px;flex-direction:column;align-items:center;justify-content:center;padding:18px;border-left:8px solid #198bc4;border-radius:5px 13px 13px 5px;background:linear-gradient(160deg,#dff5ff,#fff 58%,#fff2c9);box-shadow:0 9px 20px rgba(18,54,74,.14);text-align:center}.book-cover-fallback small{color:var(--text)}.book-cover-fallback strong{margin:10px 0;color:var(--ink);font:750 21px/1.15 var(--font-heading)}.book-cover-fallback .icon{width:42px;height:42px;color:var(--green)}
.book-overview-copy{min-width:0}.book-overview-copy>.eyebrow{margin-bottom:7px;color:var(--blue)}.book-overview-copy h1{margin:0 0 12px;font-size:clamp(32px,4vw,48px);overflow-wrap:anywhere}.book-guidance{max-width:650px;margin:12px 0 0;font-size:15px}
.book-facts{display:flex;flex-wrap:wrap;gap:8px}.book-facts span{display:inline-flex;align-items:center;min-height:30px;padding:5px 11px;border:1px solid #d6e8f1;border-radius:999px;background:#f4fbff;color:#36566a;font-size:11px;font-weight:700}
.book-overview .chapter-picker{width:100%;margin:22px 0 0;grid-template-columns:minmax(190px,.42fr) minmax(0,1fr);padding:15px 17px;border-radius:18px;box-shadow:0 10px 25px rgba(22,88,124,.09)}
.book-overview .chapter-picker-label strong{font-size:15px}.book-overview .chapter-picker-icon{flex-basis:42px;height:42px;border-radius:12px}.book-overview .chapter-picker select{height:50px}
.unit-availability{margin-top:14px;padding-top:2px}.unit-availability summary{display:inline-flex;align-items:center;min-height:36px;padding:6px 12px;border-radius:10px;color:var(--blue);font-size:12px;font-weight:700}.unit-availability summary:hover{background:#eef8fd}.unit-chip-list{display:flex;flex-wrap:wrap;gap:7px;margin-top:8px}.unit-chip-list span{padding:5px 10px;border:1px solid #d9e7ee;border-radius:999px;background:#fff;color:#486273;font-size:11px;font-weight:650}
.unit-activities-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;margin:12px 0 18px;padding:0 4px}.unit-activities-heading .eyebrow{margin-bottom:5px;color:var(--blue)}.unit-activities-heading h2{margin:0 0 5px;font-size:clamp(26px,3vw,34px)}.unit-activities-heading p{margin:0;font-size:13px}.unit-activities-heading .selected-chapter{flex:0 1 330px;display:block;margin:0;padding:10px 14px;border:1px solid #d5e8f1;border-radius:13px;background:rgba(255,255,255,.88);text-align:right}.unit-activities-heading .selected-chapter span,.unit-activities-heading .selected-chapter strong{display:block}.unit-activities-heading .selected-chapter strong{margin-top:2px;font-size:15px}

/* Login pages retain the illustrated activation-card treatment. */
.auth-page .auth-world{background:radial-gradient(ellipse at 50% 20%,#fff 20%,#eef9ff 70%,#fff6e5)}
.auth-page .auth-world .art-rail{display:block;position:absolute;top:var(--header-h);height:calc(100% - var(--header-h));width:31%;object-fit:cover;object-position:top;z-index:0}
.auth-page .auth-world .art-rail.left{left:0;object-position:left top}.auth-page .auth-world .art-rail.right{right:0;object-position:right top}
.auth-page .auth-heading,.auth-page .auth-card{position:relative;z-index:2}

/* Public activity demos. */
.demo-access-modal{width:min(92vw,480px);max-height:calc(100vh - 32px);padding:0;overflow:visible;border:0;border-radius:26px;background:transparent;color:var(--ink);box-shadow:0 28px 80px rgba(19,57,78,.3)}
.demo-access-modal::backdrop{background:rgba(15,42,60,.55);backdrop-filter:blur(5px)}
.demo-access-card{position:relative;padding:34px;border:1px solid rgba(181,218,234,.85);border-radius:26px;background:linear-gradient(150deg,#fff 58%,#eaf9ff);text-align:center}
.demo-modal-close{position:absolute;top:13px;right:15px;display:grid;width:38px;height:38px;place-items:center;padding:0;border:0;border-radius:50%;background:#edf6fa;color:#36566a;font:500 27px/1 Arial;cursor:pointer}
.demo-modal-close:hover{background:#dceff7;color:var(--blue)}
.demo-access-icon{display:grid;width:64px;height:64px;place-items:center;margin:0 auto 14px;border-radius:20px;background:linear-gradient(145deg,#fff2bd,#ffd45e);box-shadow:0 10px 24px rgba(186,132,24,.2);font-size:31px}
.demo-access-card h2{margin:4px 0 10px;font-size:clamp(25px,4vw,34px)}
.demo-access-card>p:not(.eyebrow):not(.form-status){font-size:14px}
.demo-access-card .field{display:block;margin:23px 0 12px;text-align:left}
.demo-access-card .field span{display:block;margin-bottom:7px;color:var(--ink);font-size:13px;font-weight:750}
.demo-access-card .field input{width:100%;min-height:52px;padding:12px 15px;border:1px solid #b8cfdb;border-radius:13px;background:#fff;color:var(--ink);font-size:17px;letter-spacing:.05em}
.demo-access-card .field input:focus{outline:3px solid rgba(25,139,196,.17);border-color:var(--blue)}
.demo-access-card .btn-block{width:100%;justify-content:center}
.demo-access-card .form-status{margin:0 0 12px;padding:9px 11px;border-radius:10px;background:var(--red-bg);color:var(--red);font-size:13px;font-weight:700}
.demo-access-card .demo-access-note{margin:14px 0 0!important;color:var(--muted);font-size:11px!important}
.demo-eyebrow{display:inline-flex;padding:6px 11px;border-radius:999px;background:#fff0b9;color:#805a00!important}
.demo-footer-actions{display:flex;justify-content:center;gap:12px;margin-top:25px}
.demo-test-container{max-width:900px!important}
.demo-quiz{max-width:760px;margin:0 auto;padding:clamp(22px,4vw,38px)}
.demo-quiz-top{display:flex;align-items:center;justify-content:space-between;gap:12px;color:var(--blue);font-size:13px;font-weight:750}
.demo-progress{height:9px;margin:13px 0 27px;overflow:hidden;border-radius:999px;background:#e5f1f6}.demo-progress span{display:block;width:0;height:100%;border-radius:inherit;background:linear-gradient(90deg,var(--blue),var(--cyan));transition:width .25s ease}
.demo-quiz-question{color:var(--ink);font:750 clamp(22px,3.1vw,32px)/1.25 var(--font-heading);text-align:center}
.demo-quiz-image{display:block;width:min(100%,430px);height:clamp(180px,28vh,300px);margin:20px auto;border-radius:17px;background:#f5fafc;object-fit:contain}
.demo-quiz-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:26px}
.demo-option{min-height:58px;padding:13px 16px;border:2px solid #d8e8ef;border-radius:14px;background:#fff;color:var(--ink);font:700 15px/1.25 var(--font-body);cursor:pointer;transition:transform .15s,border-color .15s,background .15s}
.demo-option:hover:not(:disabled){transform:translateY(-2px);border-color:var(--blue);background:#f2fbff}.demo-option.is-correct{border-color:#4dae73;background:#eaf9ef;color:#17613d}.demo-option.is-wrong{border-color:#df6570;background:#fff0f1;color:#9f2732}.demo-option:disabled{cursor:default}
.demo-quiz-feedback{min-height:24px;margin:17px 0 0;text-align:center;font-weight:750}.demo-quiz-feedback.is-correct{color:#23804b}.demo-quiz-feedback.is-wrong{color:#b23842}.demo-quiz-next{display:flex;margin:14px auto 0}.demo-quiz-result{padding:25px 0;text-align:center}.demo-quiz-result>span{font-size:66px}.demo-quiz-result h2{margin:10px 0;font-size:36px}.demo-quiz-result .btn{margin:20px auto 0}
@media (max-width:620px){.demo-access-card{padding:29px 21px 24px}.demo-footer-actions{align-items:stretch;flex-direction:column}.demo-footer-actions .btn{justify-content:center}.demo-quiz-options{grid-template-columns:1fr}.demo-quiz{padding:21px 16px}.demo-quiz-image{height:210px}}

/* Mirror the inner-edge fade on the two authentication illustrations. */
.auth-world .art-rail.left {
  -webkit-mask-image: linear-gradient(to right, #000 0%, #000 58%, rgba(0, 0, 0, .72) 76%, transparent 100%);
  mask-image: linear-gradient(to right, #000 0%, #000 58%, rgba(0, 0, 0, .72) 76%, transparent 100%);
}

.auth-world .art-rail.right {
  -webkit-mask-image: linear-gradient(to left, #000 0%, #000 58%, rgba(0, 0, 0, .72) 76%, transparent 100%);
  mask-image: linear-gradient(to left, #000 0%, #000 58%, rgba(0, 0, 0, .72) 76%, transparent 100%);
}

.question-image-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.question-image-grid img {
  display: block;
  width: 100%;
  height: clamp(170px, 20vw, 260px);
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
  object-fit: contain;
}