/* 1. Foundation and shared navigation */
:root{--ink:#183e3d;--muted:#607775;--accent:#17766b;--line:#dce6e2;--paper:#fff;--wash:#f4f7f4}
body.student-page,body.admin-page{background:var(--wash);color:var(--ink);font-family:'Plus Jakarta Sans',Arial,sans-serif;-webkit-font-smoothing:antialiased}
button,a,input,select,textarea{touch-action:manipulation}
button,a,input,select,textarea,summary{outline-offset:4px}
:focus-visible{outline:3px solid #b87924!important}
button{transition:background .18s,color .18s,border-color .18s!important}
button:disabled{cursor:not-allowed}
input[type=radio],input[type=checkbox]{accent-color:var(--accent);flex-shrink:0;width:16px;height:16px;margin-top:3px}
.skip-link{position:absolute;top:-80px;left:20px;z-index:100;background:white;padding:12px}.skip-link:focus{top:10px}
.site-header{background:#fff;border-bottom:1px solid var(--line)}
.header-inner{max-width:1280px;margin:auto;padding:20px 32px;display:flex;align-items:center;justify-content:space-between;gap:20px}
.brand{display:flex;gap:12px;align-items:center;font-weight:800;font-size:22px;letter-spacing:-.7px;color:var(--ink)}
.brand small{display:block;font-size:9px;letter-spacing:2.3px;color:var(--muted);margin-top:3px}
.brand-mark{display:flex;align-items:center;justify-content:center;width:44px;height:44px;border-radius:13px;background:var(--ink);color:#fff;font-size:25px;letter-spacing:-4px;padding-right:4px}.brand-mark span{color:#a6d5bd}
.site-header nav,#authHeader{display:flex;align-items:center;gap:22px;font-size:12px;font-weight:700}
.site-header nav>a{color:var(--muted)}
.site-header button{border:1px solid var(--line);background:white;color:var(--ink);border-radius:9px;padding:10px 14px}
.site-header button:hover{background:#edf4ef}
.site-footer{max-width:1280px;width:100%;margin:40px auto 0;padding:26px 32px;border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:16px;color:var(--muted);font-size:11px}
/* 2. Intro: student and teacher */
.page-intro{max-width:1280px;width:100%;margin:auto;padding:46px 32px 36px;display:flex;justify-content:space-between;align-items:center;gap:48px}
.eyebrow{font-size:10px;font-weight:800;letter-spacing:2px;color:var(--accent);margin-bottom:15px}
.page-intro h1{font-size:clamp(30px,3.2vw,43px);line-height:1.2;font-weight:800;letter-spacing:-1.8px}.page-intro h1 span{color:var(--accent)}
.intro-copy{font-size:14px;line-height:1.8;color:var(--muted);max-width:535px;margin-top:17px}
.intro-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:22px}.intro-tags span{font-size:10px;font-weight:700;border:1px solid var(--line);border-radius:6px;padding:7px 10px;background:#fff8}
.study-note{position:relative;flex:0 0 330px;border-left:2px solid #bfd2c5;padding:15px 0 15px 30px;color:var(--muted);overflow:hidden}.note-index{font-size:9px;letter-spacing:1.8px;font-weight:800}.study-note p{font-size:12px;margin-top:18px}.study-note b{color:var(--ink)}.study-note svg{width:180px;height:60px;margin-top:15px;fill:none;stroke:#7ba996;stroke-width:1.5}
/* 3. Student filters and result toolbar */
.student-page main{padding:0 32px;gap:26px;align-items:flex-start}
.filter-panel{width:330px!important;flex-shrink:0;padding:24px!important;border:1px solid var(--line)!important;border-radius:16px!important;background:white!important;box-shadow:0 5px 22px #203a3210!important}
.filter-panel>div:first-child>div:first-child>span,.results-panel>div:first-child>div:first-child>span:first-child,#btnApplySearch>span:first-child{display:none}
.filter-panel label{color:var(--muted);font-size:10px;letter-spacing:1px}
.filter-panel button{font-weight:600;box-shadow:none!important}
#screenerTitle{font-size:15px;color:var(--ink)}
#domainAccordionContainer{max-height:340px;scrollbar-width:thin;scrollbar-color:#b7cbc1 transparent}
#domainAccordionContainer>div{border:1px solid var(--line);border-radius:9px;box-shadow:none}
#domainAccordionContainer>div>button{background:#f4f7f4;color:var(--ink);font-size:11px;min-height:45px;border:0}
#domainAccordionContainer button[aria-pressed]{font-size:11px;padding:7px 9px;line-height:1.5;text-align:left;border-radius:6px}
.filter-panel button[aria-pressed=true]{background:var(--accent)!important;background-image:none!important;color:#fff!important;border-color:var(--accent)!important}
.filter-panel button[aria-pressed=false]{background:#fff!important;color:var(--muted)!important;border-color:var(--line)!important}
#paperFilterContainer,#typeFilterContainer{gap:5px;flex-wrap:wrap}
#typeFilterContainer button{font-size:10px;padding:9px 7px}
#levelFilterContainer button{min-height:33px}
.filter-panel select{background:#f6f8f6;font-size:12px;min-height:42px;font-weight:600;border-color:var(--line)}
#searchModeHint{font-size:11px;line-height:1.65;color:var(--muted);background:#f6f8f6;border:0}
#btnApplySearch{background:var(--accent);border-radius:9px;font-size:12px;min-height:46px;transform:none}
#btnApplySearch:hover{background:#105d54}
.results-panel{width:auto!important;flex:1;min-width:0}
.results-panel>div:first-child{background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:none;padding:15px 20px}
#questionCount{background:#e9f3ee;color:var(--accent);box-shadow:none;font-size:12px}
#groupByYearBtn{background:#f5f7f5;color:var(--ink);border:1px solid var(--line);border-radius:7px;box-shadow:none;font-size:11px}
#practiceProgress{margin:16px 0;padding:20px 22px;background:#eaf2ec;border-color:#d8e5dc;box-shadow:none}
#practiceProgress [data-score]{font-size:14px;color:var(--ink)}
#practiceProgress [data-storage]{font-size:11px;color:var(--muted);max-width:580px;line-height:1.7}
#practiceProgress .upgrade-actions{margin-bottom:0}
#practiceProgress button{font-size:11px;background:#fff9;border:1px solid #cbded1;color:var(--ink);padding:8px 11px}
#practiceProgress [data-clear]{background:transparent;border-color:transparent;color:var(--muted)}
#dbStatus{font-size:12px;line-height:1.7}
#questionsList>div:not(.upgrade-panel):not(:has(article)){background:#fff;border:1px dashed #c4d7cd;border-radius:14px;box-shadow:none}
#questionsList>div>div.bg-gradient-to-r{background:var(--ink);border-radius:12px 12px 0 0;box-shadow:none}
/* 4. Questions, answers and shared previews */
.upgrade-panel{border-color:var(--line);border-radius:14px;padding:26px;color:var(--ink);font-size:14px;box-shadow:0 3px 14px #193d3005}
.upgrade-panel h2{font-size:17px;letter-spacing:-.3px}
.practice-meta{font-size:11px;line-height:1.9;color:var(--muted);padding-bottom:16px;border-bottom:1px solid var(--line);margin-bottom:20px}
.question-copy{font-size:15px;line-height:1.9;margin:18px 0;color:#263c3b}
.practice-choice{padding:14px 16px;border-color:var(--line);border-radius:9px;margin:10px 0;line-height:1.7;font-size:14px;background:#fff}
.practice-choice:hover{background:#f6f9f6;border-color:#9cbeb0}
.practice-choice:has(input:checked){background:#edf6ef;border-color:var(--accent);box-shadow:inset 3px 0 var(--accent)}
.practice-choice b{color:var(--accent);margin-right:8px}
.upgrade-button{background:var(--accent);padding:11px 16px;border-radius:8px;font-size:12px;font-weight:700}
.upgrade-button:hover{background:#105d54}.upgrade-button.secondary{background:#edf3ef;color:var(--ink)}.upgrade-button.secondary:hover{background:#ddebe2}
.upgrade-button:disabled{opacity:.5;cursor:not-allowed}
.practice-text{font-size:14px;line-height:1.8;border-color:#c5d5cd;border-radius:9px;min-height:130px;resize:vertical;background:#fcfdfb}
.practice-answer{background:#edf6ef;border-color:#c8dfcf;border-radius:9px;line-height:1.8}
.question-part{border-color:var(--line);padding-top:20px;margin-top:22px}.question-part summary{cursor:pointer;font-size:12px;color:var(--accent);font-weight:700}
.upgrade-status{background:#eef3f0;color:#49635d;border-radius:8px;font-size:12px;line-height:1.7}.upgrade-error{color:#991b1b;background:#fef2f2}.upgrade-success{color:#065f46;background:#ecfdf5}
.preview-language{border-color:var(--line);padding:18px}.preview-language .question-copy{font-size:13px}
/* 5. Teacher workspace, PDF and JSON editor */
.admin-page{font-family:'Plus Jakarta Sans',Arial,sans-serif}
.admin-intro{padding-bottom:24px}.admin-intro h1{font-size:34px}.admin-intro .intro-tags{max-width:160px}
#loginCard{margin:28px auto 60px;padding:36px;border:1px solid var(--line);border-radius:16px;box-shadow:0 12px 40px #163b3210;width:calc(100% - 40px)}
#loginCard h2{color:var(--ink);font-size:22px}#loginCard p{font-size:13px;line-height:1.8}#loginCard button{background:var(--accent);border-radius:8px;box-shadow:none}
#adminPanel{padding:16px 32px;gap:24px}#adminPanel>section,#repairPanel>div,#optimizePanel>div{border:1px solid var(--line);border-radius:14px;box-shadow:0 4px 16px #173c3206;padding:24px;min-width:0}
.admin-page h2{color:var(--ink)!important}.admin-page button{border-radius:7px;box-shadow:none;font-size:12px;line-height:1.6}
#adminPanel button[class*=bg-blue],#adminPanel button[class*=bg-indigo],#adminPanel button[class*=bg-emerald],#adminPanel button[class*=bg-green]{background:var(--accent)}
#adminPanel .bg-blue-50{background:#f1f6f2;border-color:var(--line);padding:15px}
#jsonPasteBox{background:#fcfdfc;color:#244e44;font-size:12px;line-height:1.8;padding:16px;border-color:#ccdad2;border-radius:8px;resize:vertical}
#adminPanel .upgrade-panel{box-shadow:none;background:#fbfcfa;padding:20px}
#adminPanel input[type=file]{font-size:12px;width:100%;padding:12px;border:1px dashed #b5ccbe;border-radius:8px;background:#f6f9f5}
input[type=file]::file-selector-button{border:0;background:#e1ede4;color:var(--ink);padding:8px 11px;border-radius:5px;margin-right:12px;cursor:pointer}
#repairPanel,#optimizePanel{padding:12px 32px;width:100%}
#authHeader{font-size:11px;flex-wrap:wrap;gap:10px}
#authHeader[hidden]{display:none}
/* 6. Responsive layouts and motion preference */
@media(max-width:1023px){.student-page main{flex-direction:column}.filter-panel{width:100%!important}.results-panel{width:100%!important}#domainAccordionContainer{max-height:240px}.study-note{flex-basis:270px;padding-left:22px}.page-intro{gap:25px}.preview-grid{grid-template-columns:1fr}}
@media(max-width:640px){.header-inner{padding:16px 20px}.brand{font-size:19px}.brand-mark{width:36px;height:36px;font-size:23px}.brand small{font-size:8px;letter-spacing:1.6px}.site-header nav{gap:12px;font-size:10px}.site-header nav>a{max-width:74px}.site-header button{padding:8px 10px;font-size:11px}.page-intro{padding:30px 20px 26px}.page-intro h1{font-size:31px;letter-spacing:-1.2px}.intro-copy{font-size:13px}.study-note{display:none}.student-page main{padding:0 16px;gap:18px}.filter-panel{padding:20px!important}.upgrade-panel{padding:20px}.question-copy{font-size:14px}.practice-choice{padding:12px}.intro-tags{gap:6px}.intro-tags span{font-size:9px;padding:6px 8px}.site-footer{padding:22px 20px;flex-direction:column;font-size:10px}.admin-intro{display:block}.admin-intro .intro-tags{max-width:none}#adminPanel{padding:12px 16px;grid-template-columns:1fr}#adminPanel>section{padding:18px}#repairPanel,#optimizePanel{padding:10px 16px}#authHeader{max-width:125px}#userInfo{overflow-wrap:anywhere}.results-panel>div:first-child{padding:14px}.preview-language{padding:12px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}

/* 7. Biology identity — illustrations, fresh palette and topic accents */
:root{--ink:#242c4e;--muted:#646c88;--accent:#6650cc;--line:#e1e5f1;--wash:#f6f8fe}
body.student-page,body.admin-page{background:radial-gradient(ellipse at 85% 7%,#e9e4ff 0,transparent 34%),radial-gradient(ellipse at 8% 20%,#e7faf0 0,transparent 28%),var(--wash)}
.brand-mark{background:#6650cc;box-shadow:4px 4px 0 #d5f493;border-radius:15px}.brand-mark span{color:#d5f493}
.site-header{background:#ffffffed}.site-header button{border-radius:12px}
.page-intro{gap:24px;padding-top:30px;padding-bottom:28px;min-height:345px}
.page-intro>div:first-child{flex:1;min-width:0}.page-intro h1{font-size:clamp(32px,3.4vw,46px);letter-spacing:-1.8px;line-height:1.16}.page-intro h1 span{color:#6650cc}
.eyebrow{display:inline-block;padding:7px 11px;border-radius:30px;background:#e4f7ce;color:#3e6633;letter-spacing:1.5px;font-size:9px}
.intro-copy{max-width:510px}.intro-tags span{border-radius:20px;background:#fff;border-color:#dfe3f0}.intro-tags span:first-child{background:#eee9ff;color:#634bb8;border-color:#e0d7ff}.intro-tags span:nth-child(2){background:#e2f9f1;color:#267461;border-color:#cbecdf}
.biology-art{position:relative;flex:0 1 450px;max-width:46%;min-width:0}.biology-art img{width:100%;height:auto}.specimen-tag,.specimen-caption{position:absolute;font-size:9px;letter-spacing:1.6px;font-weight:800;color:#787994}.specimen-tag{top:0;left:32px}.specimen-caption{bottom:4px;right:24px}
.filter-panel{border-radius:20px!important;box-shadow:0 8px 25px #60579a08!important}.results-panel>div:first-child{border-radius:15px}
#domainAccordionContainer>div:nth-child(5n+1)>button{background:#e9f8ef;color:#366a50}#domainAccordionContainer>div:nth-child(5n+2)>button{background:#eee9ff;color:#63519f}#domainAccordionContainer>div:nth-child(5n+3)>button{background:#eff6de;color:#596c37}#domainAccordionContainer>div:nth-child(5n+4)>button{background:#fff0e6;color:#946545}#domainAccordionContainer>div:nth-child(5n)>button{background:#e9f3ff;color:#416b93}
.filter-panel button[aria-pressed=true]{background:#eee9ff!important;color:#5940ab!important;border-color:#d7caf6!important}
#btnApplySearch,.upgrade-button{background:#6650cc;box-shadow:0 4px 10px #6650cc20}#btnApplySearch:hover,.upgrade-button:hover{background:#523ab6}
#practiceProgress{background:linear-gradient(110deg,#eeebff,#edf7fd);border-color:#e0def3;border-radius:16px}#practiceProgress button{border-color:#d7d1ee;background:#ffffffb0}.upgrade-button.secondary{background:#efecfa;color:#584895}
#questionCount{background:#e8e1ff;color:#654cb8}.practice-choice:has(input:checked){background:#f1edff;border-color:#8b76d9;box-shadow:inset 3px 0 #8b76d9}.practice-choice:hover{background:#f7f5ff;border-color:#bbabe7}.practice-choice b{color:#6650cc}
.practice-answer{background:#effaf3;border-color:#cce9d6}.upgrade-panel{border-radius:18px}.practice-meta{color:#70748d}#loginCard button{background:#6650cc}
.admin-intro .biology-art{max-width:300px}.admin-intro h1{font-size:36px}
@media(max-width:760px){.page-intro{gap:12px}.biology-art{flex-basis:280px;max-width:40%}.specimen-tag,.specimen-caption{font-size:7px;letter-spacing:1px}.page-intro h1{font-size:33px}}
@media(max-width:640px){.page-intro{position:relative;display:block;padding:30px 20px 22px;min-height:0}.page-intro>div:first-child{position:relative;z-index:1}.page-intro h1{font-size:34px;max-width:350px}.biology-art{max-width:280px;width:85%;margin:22px auto 0}.biology-art img{max-height:175px;object-fit:contain}.specimen-tag{left:8px;top:0}.specimen-caption{right:0;bottom:-4px}.admin-intro .biology-art{max-width:230px}.admin-intro h1{font-size:31px}.intro-copy{font-size:13px}.filter-panel{border-radius:18px!important}}

/* 8. Study dashboard, bookmarks and spaced revision */
.answer-data-notice{padding:12px;border:1px solid #eed59f;border-radius:8px;background:#fff8e9;color:#795922;font-size:12px;line-height:1.7}
.study-panel{background:linear-gradient(135deg,#fff,#f7f5ff);margin:16px 0;padding:22px}
.study-heading{display:flex;justify-content:space-between;align-items:center}.study-heading h2{margin:0}.study-heading>span{color:#a18adf;font-size:25px}
.study-panel>[data-study-caption]{font-size:12px;color:var(--muted);margin:6px 0 16px}
.study-stats{display:grid;grid-template-columns:repeat(4,1fr);gap:10px}.study-stats>div{padding:13px;background:#fff;border:1px solid #e6e1f5;border-radius:12px}.study-stats b{display:block;color:#6650cc;font-size:23px;line-height:1.4}.study-stats span{font-size:10px;color:var(--muted);display:block;margin-top:4px}
.study-note-copy,.study-storage{font-size:11px;line-height:1.7;color:var(--muted)}.study-storage{margin-top:14px!important}
.chapter-details{border-top:1px solid var(--line);margin-top:16px;padding-top:14px}.chapter-details summary{font-size:12px;font-weight:700;cursor:pointer;color:#5948a2}.chapter-details [data-chapters]{max-height:320px;overflow:auto;margin-top:12px;scrollbar-width:thin}
.chapter-progress{display:grid;grid-template-columns:1fr auto;gap:8px;align-items:center;padding:12px 0;border-bottom:1px solid var(--line)}.chapter-progress b{font-size:11px}.chapter-progress small{display:block;font-size:10px;color:var(--muted);margin-top:4px}.chapter-progress>span{font-size:13px;color:#6650cc;font-weight:700}.chapter-progress progress{grid-column:1/-1;width:100%;height:6px;border:0;border-radius:9px;overflow:hidden;accent-color:#9680dd}.chapter-progress progress::-webkit-progress-bar{background:#eae6f4}.chapter-progress progress::-webkit-progress-value{background:#9680dd;border-radius:9px}.study-empty{font-size:12px;color:var(--muted)}
.question-tools{display:flex;justify-content:flex-end;margin-bottom:10px}.study-bookmark{border:1px solid #e4dcf6;color:#705baf;border-radius:20px;padding:7px 11px;font-size:11px;font-weight:700;background:#faf8ff}.study-bookmark[aria-pressed=true]{background:#eee6ff;border-color:#c7b4ee;color:#6242a9}.study-bookmark:hover{background:#eee6ff}
.study-set-notice{padding:12px 16px;border:1px solid #d8ccec;border-radius:10px;background:#f4efff;font-size:12px;color:#654d93;margin:16px 0}
@media(max-width:640px){.study-panel{padding:18px}.study-stats{grid-template-columns:repeat(2,1fr);gap:8px}.study-stats>div{padding:12px}.study-stats b{font-size:22px}}