:root{--ink:#392d23;--muted:#706658;--green:#397544;--cream:#fffdf7;--layout-gap:26px;color-scheme:light}
*{box-sizing:border-box}body{margin:0;min-width:1180px;min-height:100vh;color:var(--ink);font-family:system-ui,-apple-system,'Apple SD Gothic Neo',sans-serif;background:#ecd4b1 url('/assets/service-scenes-v6/world-study-room-v6.png') center center/cover fixed no-repeat}button,input{font:inherit}svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}.icon-definitions{position:absolute;width:0;height:0;overflow:hidden}
.site-header{height:70px;margin:25px 2.6vw 0;padding:0 23px;display:flex;justify-content:space-between;align-items:center;gap:22px;background:#fffdf9fa;border:1px solid #fff9;border-radius:27px;box-shadow:0 3px 12px #6a451d0a}
.brand{display:flex;align-items:center;gap:12px;flex-shrink:0}.brand strong{font-size:25px;letter-spacing:-1.1px;line-height:1.15;color:#493325}.brand em{font-style:normal;color:#29713b}.brand small{display:block;font-size:8px;letter-spacing:3.4px;margin-top:6px;color:#7c6f61}.brand-face{position:relative;display:block;width:42px;height:42px;border-radius:48% 50% 42% 44%;background:radial-gradient(circle at 30% 24%,#fff6bc,#f4cf69 70%);box-shadow:inset -2px -4px 5px #ceaa4033,0 3px 5px #c3a56730}.brand-face::before,.brand-face::after{content:'';position:absolute;width:3px;height:5px;top:17px;background:#6b5738;border-radius:50%}.brand-face::before{left:12px}.brand-face::after{right:12px}.brand-face i{position:absolute;width:8px;height:5px;top:23px;left:17px;border-bottom:1.5px solid #6b5738;border-radius:0 0 50% 50%}
nav{display:flex;align-items:center;gap:9px}.nav-item{display:flex;align-items:center;gap:8px;padding:12px 13px;font-size:14px;font-weight:650;white-space:nowrap}.nav-item.is-current{border:1px solid #e0ebd7;border-radius:15px;background:#edf4e5;color:#2f6d36}.coral{color:#e36440}.amber{color:#bc7e18}.violet{color:#8d73ba}.blue{color:#3c91a2}.account-preview{display:flex;align-items:center;gap:9px;font-size:12px;font-weight:600;white-space:nowrap}.student-avatar{display:grid;place-items:center;width:32px;height:32px;border:1px solid #d7b56f;border-radius:50%;background:linear-gradient(120deg,#fff2b1,#e6bc64);font-size:21px;font-style:italic;color:#81713a}.logout-preview{margin-left:6px;padding:10px 15px;border:1px solid #e4d6c3;border-radius:25px;color:#897e70;font-weight:500}
.library-layout{display:grid;grid-template-columns:minmax(0,1.63fr) minmax(360px,1fr);gap:var(--layout-gap);align-items:start;width:min(1256px,max(1080px,75vw));margin:50px clamp(48px,9.4vw,180px) 0 auto}.open-library{position:relative;min-width:0}.library-tools{position:relative;z-index:1;margin-bottom:36px}.library-tools::before{content:'';position:absolute;z-index:-1;inset:-22px -20px -22px;background:radial-gradient(ellipse at 45% 55%,#fffaf2ed 0%,#fffaf2c2 46%,#fffaf260 68%,transparent 82%);filter:blur(9px);pointer-events:none}.heading-row{display:flex;align-items:center;justify-content:space-between;gap:22px;min-height:78px}h1{margin:0;font-size:40px;line-height:1.25;letter-spacing:-1.8px;font-weight:780}.heading-row p{font-size:16px;line-height:1.5;margin:4px 0 0;white-space:nowrap}.search-preview{display:flex;align-items:center;gap:10px;flex:1;max-width:420px;min-width:180px;height:46px;padding:0 16px;background:#fffdf8f5;border:1px solid #cfc4b4;border-radius:30px;box-shadow:0 2px 5px #72513708;color:#89755d}.search-preview svg{width:18px;height:18px}.search-preview input{min-width:0;width:100%;border:0;background:transparent;outline:0;font-size:14px;color:#786f62;opacity:1;-webkit-text-fill-color:#8a8175}.filter-row{display:flex;align-items:center;gap:14px;margin-top:21px;white-space:nowrap}.path-switch{display:flex;align-items:center;flex-shrink:0;padding:3px;background:#fffdf8f5;border:1px solid #e0d5c4;border-radius:26px}.path-switch span{min-width:82px;padding:9px 15px;text-align:center;font-size:13px;font-weight:700;color:#4d5047}.path-switch .is-current{background:linear-gradient(#5f9654,#3d7545);border-radius:24px;color:#fff}.topic-chips{display:flex;align-items:center;gap:7px;min-width:0;flex:1}.topic-chip{display:flex;align-items:center;justify-content:center;gap:6px;padding:10px 12px;border:1px solid #e4d8c8;background:#fffdf8f5;border-radius:24px;font-size:12px;font-weight:650;white-space:nowrap;box-shadow:0 2px 4px #78502306}.topic-chip.is-current{border-color:#52824b;background:#edf4e4;color:#37673b}.topic-chip svg{width:11px;height:11px;transform:rotate(90deg)}.topic-count{margin-left:auto;font-size:13px;font-weight:650}
.shelf-rows{display:grid;gap:26px}.shelf-books-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));align-items:end;gap:40px;padding:0 49px}.book-button{max-width:196px;justify-self:center;cursor:default}.book-button:hover{transform:none}.wood-shelf{position:relative;height:19px;margin-top:5px;border:1px solid #c38d56;border-radius:2px;background:repeating-linear-gradient(0deg,#9d632812 0 1px,transparent 2px 4px),linear-gradient(#efc293,#d7a36b 42%,#c48c53);box-shadow:inset 0 2px #fce0b5,inset 0 -3px #a7723726,0 7px 10px #68401d30}.wood-shelf::before{content:'';position:absolute;left:-1px;right:-1px;top:-8px;height:8px;border:1px solid #dfae78;transform:skewX(-18deg);transform-origin:bottom;background:linear-gradient(#f9d6b0,#edbf8a)}
.sv-book[data-variant='signature-detail'] .sv-book__content{top:55%}.sv-book[data-variant='signature-detail'] .sv-book__title{font-size:min(var(--book-title-size),12cqw);line-height:1.3}.sv-book[data-variant='signature-detail'] .sv-book__rule{margin-top:4cqw}.sv-book[data-variant='signature-detail'] .sv-book__subtitle{margin-top:3.5cqw;font-size:6cqw;line-height:1.4}.sv-book[data-variant='signature-detail'] .sv-book__frame{opacity:.68}
.shelf-footer{position:relative;text-align:center;padding-top:22px}.shelf-pager{display:flex;align-items:center;justify-content:center;gap:29px}.shelf-pager button{display:grid;place-items:center;width:43px;height:43px;border:1px solid #d8c4a4;border-radius:50%;background:#fffaf1f5;color:#5a6b47;box-shadow:0 2px 4px #65442b12;opacity:1}.shelf-pager button svg{width:16px;height:16px}.shelf-pager .previous svg{transform:rotate(180deg)}.shelf-pager strong{font-size:15px;color:#443d2d}.shelf-footer p{font-size:12px;color:#5b4e3d;margin:7px 0 0;text-shadow:0 1px #fff9}
.detail-panel{padding:25px 30px 22px;border-radius:20px;background:#fffdf8fa;border:1px solid #fff4e3;box-shadow:0 9px 22px #70503020;min-width:0}.detail-eyebrow{display:table;padding:6px 12px;border-radius:10px;background:#e9f1df;color:#3c6f3c;font-size:14px;line-height:1.2;font-weight:700;margin-bottom:10px}.level-pill{display:table;padding:4px 10px;background:#f5e9d5;border-radius:20px;color:#806849;font-size:12px;margin-bottom:7px}.detail-panel h2{font-size:30px;font-weight:760;line-height:1.38;letter-spacing:-1.2px;text-wrap:balance;word-break:keep-all;margin:0;max-width:360px}.book-intro{font-size:14px;color:#665d4f;line-height:1.7;word-break:keep-all;margin:13px 0 25px}.contents-heading{display:flex;justify-content:space-between;align-items:baseline;gap:10px;margin:0 0 12px}.contents-heading h3{font-size:19px;letter-spacing:-.6px;margin:0;white-space:nowrap}.contents-heading span{font-size:12px;white-space:nowrap;color:#766a59}.lesson-list{border:1px solid #dfd5c6;border-radius:10px;overflow:hidden;background:#fffefb80}.lesson-row{display:grid;grid-template-columns:26px minmax(0,1fr) auto 10px;align-items:center;gap:9px;min-height:50px;padding:10px 15px;border-bottom:1px solid #e9e0d2;color:#3c3f32}.lesson-row:last-child{border-bottom:0}.lesson-number{font-size:13px;color:#776d58;font-variant-numeric:tabular-nums}.lesson-title{font-size:14px;line-height:1.45;letter-spacing:-.25px;font-weight:650;word-break:keep-all}.lesson-count{font-size:11px;color:#6a6a5a;white-space:nowrap}.lesson-row>svg{width:12px;height:12px;color:#5b7948}.lesson-row.is-selected{background:#e6efdc;box-shadow:inset 2px 0 #50814b}.lesson-check{display:grid;place-items:center;width:23px;height:23px;border-radius:50%;background:#347340;color:white}.lesson-check svg{width:15px;height:15px;stroke-width:2.3}.learning-availability{margin-top:20px}.start{display:flex;align-items:center;justify-content:center;gap:13px;width:100%;min-height:55px;border:1px solid #447947;border-radius:13px;background:linear-gradient(#5c9758,#3a7240);color:#fff;opacity:1;font-size:18px;font-weight:700;box-shadow:inset 0 1px #ffffff20,0 3px 5px #47673c1c}.start svg{width:21px;height:21px}.learning-availability p{text-align:center;font-size:11px;margin:8px 0 0;color:#81755f;line-height:1.4}.preview-note{text-align:right;margin:22px clamp(48px,9.4vw,180px) 16px auto;font-size:11px;color:#635641;text-shadow:0 1px 2px #fff}
/* Desktop layout study only; mobile layout belongs to a separate design phase. */
.detail-eyebrow{margin-top:0}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
/* The reference uses wider, shorter covers so both shelves sit above the desk edge. */
.shelf-rows{gap:18px}.book-button{max-width:190px}.shelf-books-grid .sv-book{aspect-ratio:9/10}
.library-tools{container-type:inline-size}.path-switch span{min-width:clamp(82px,13cqw,101px)}.filter-row{gap:clamp(14px,2.6cqw,22px)}.topic-chip{font-size:clamp(12px,1.75cqw,13.5px);padding-inline:clamp(10px,1.85cqw,14px)}
body{display:flow-root;min-height:100vh}
.preview-note{margin-top:14px;margin-bottom:8px}

/* Stage 2: navigation and selection within the approved desktop composition. */
button{cursor:pointer}button:disabled{cursor:default}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #50814b;outline-offset:3px}
.path-switch button{min-width:clamp(82px,13cqw,101px);padding:9px 15px;border:0;border-radius:24px;background:transparent;text-align:center;font-size:13px;font-weight:700;color:#4d5047;min-height:38px}.path-switch button:hover:not(.is-current){background:#f2f0e6}
.topic-chip{min-height:40px;min-width:0;color:#554b3e;cursor:pointer}.chip-label{min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.topic-chip:not(.all-topics){max-width:clamp(85px,16cqw,130px)}.topic-chip:hover{border-color:#9aab83;background:#f8faef}.topic-chip.is-current:hover{background:#edf4e4}.all-topics{flex-shrink:0}.topic-count{white-space:nowrap;font-variant-numeric:tabular-nums}
.search-preview:focus-within{outline:2px solid #50814b;outline-offset:3px}.search-preview input{height:42px;-webkit-text-fill-color:#4b5140;color:#4b5140}.search-preview input::placeholder{-webkit-text-fill-color:#8a8175;font-size:13px}.search-preview input:focus-visible{outline:0}
.shelf-rows{position:relative}.book-placeholder{display:block;width:100%;max-width:190px;aspect-ratio:9/10;justify-self:center;pointer-events:none}.book-button{cursor:pointer}.book-button:hover{transform:translateY(-3px)}.shelf-pager button:disabled{background:#f8efdfd9;color:#b4a58e;border-color:#dfceb3;box-shadow:none}.shelf-pager button:not(:disabled):hover{background:#f2f6e8;border-color:#78915f}
.empty-shelf-message{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;pointer-events:none;padding:30px;color:#4a4737}.empty-shelf-message::before{content:'';position:absolute;inset:25% 5%;background:#fffaf0e8;border-radius:20px;box-shadow:0 6px 20px #8b60331a;z-index:0}.empty-shelf-message>*{position:relative;margin:0}.empty-shelf-message h2{font-size:22px;letter-spacing:-.7px}.empty-shelf-message p{font-size:14px;line-height:1.7;margin:12px 0 16px}.empty-shelf-message button{pointer-events:auto;padding:10px 18px;border:1px solid #849974;background:#edf4e4;color:#3e6b3d;border-radius:20px}
.lesson-list{max-height:352px;overflow:auto;scrollbar-width:thin;scrollbar-color:#9aa988 #f4f1e7}.lesson-row{width:100%;border:0;border-bottom:1px solid #e9e0d2;background:transparent;text-align:left;font:inherit}.lesson-row:hover{background:#f1f5e9}.lesson-row.is-selected{background:#e6efdc}.lesson-row:focus-visible{outline-offset:-3px}.lesson-number{display:flex;align-items:center}.selection-status{margin:10px 0 0;min-height:18px;font-size:12px;color:#4b6d42;line-height:1.5;word-break:keep-all}.learning-availability{margin-top:13px}.detail-empty{min-height:435px;display:flex;flex-direction:column;justify-content:center;padding:20px 0}.detail-empty .detail-eyebrow{align-self:flex-start}.detail-empty h2{font-size:27px}.detail-empty p{font-size:15px;line-height:1.8;color:#756854}
#scope-dialog{width:min(880px,86vw);max-height:84vh;padding:32px;border:1px solid #ecddc6;border-radius:22px;background:#fffdf7;color:#392d23;box-shadow:0 20px 65px #39261055}#scope-dialog::backdrop{background:#31251866;backdrop-filter:blur(4px)}.dialog-close{position:absolute;right:12px;top:10px;width:44px;height:44px;border:0;border-radius:50%;background:transparent;color:#756653;font-size:28px}.dialog-close:hover{background:#f3ecdf}.scope-dialog-head h2{font-size:27px;letter-spacing:-1px;margin:0 0 8px}.scope-dialog-head p{font-size:14px;color:#776a56;margin:0 0 20px}#scope-search{width:100%;height:46px;padding:0 15px;border:1px solid #c8c2aa;border-radius:10px;background:#fffef9;color:#494637;font:inherit;font-size:14px}.scope-result-count{font-size:12px;color:#6f725e;margin:14px 0 10px}.scope-choice-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;max-height:46vh;overflow:auto;padding:4px;scrollbar-width:thin;scrollbar-color:#99a487 #f3efdf}.scope-choice{display:flex;align-items:center;justify-content:space-between;gap:8px;min-height:61px;padding:13px;border:1px solid #e6decc;border-radius:10px;background:#fffaf0;text-align:left;color:#534a3b}.scope-choice strong{font-size:14px;line-height:1.5;font-weight:650;word-break:keep-all}.scope-choice span{font-size:11px;white-space:nowrap;color:#6f745d}.scope-choice:hover,.scope-choice.is-current{background:#edf4e4;border-color:#668b52;color:#34673c}.scope-choice.is-current{box-shadow:inset 0 0 0 1px #668b52}.scope-no-results{padding:30px;text-align:center;font-size:14px;color:#7a705e}.ready-message{padding:22px 20px;text-align:center}.ready-message .detail-eyebrow{margin:0 auto 15px}.ready-message h2{font-size:26px;line-height:1.5;margin:0 0 15px}.ready-message p{color:#736953;font-size:14px;line-height:1.8}.ready-confirm{padding:12px 32px;border:1px solid #62824d;border-radius:12px;background:#e8f0dd;color:#3b663c;font-weight:650;margin-top:12px}.load-error{grid-column:1/-1;padding:50px;background:#fffaf0;border-radius:20px}.load-error h1{font-size:30px}.load-error button{padding:12px 20px;background:#e8f0dd;border:1px solid #7d955f;border-radius:12px}