/* Editorial exam-paper look: cream paper, ink, one deep green, one red pen. Hairlines, small radii, no shadows. */
:root{
  /* tokens per critique §9.3 (contrast on --paper: ink 16.1, ink2 9.0, ink3 5.4, green 9.5, red 6.7; focus 9.5 >= 3:1) */
  --paper:#FBF8F1; --paper2:#F3EEE3; --sheet:#FFFFFF; --ink:#1B1C1A; --ink2:#45463F; --ink3:#67665E; --rule:#D8D1C2; --rule2:#1B1C1A; --rule-input:#857D6E;
  --green:#0E4B39; --green-tint:#E5EEE8; --red:#A8251C; --red-tint:#F8E6E3; --amber:#8A5A00; --focus:#0E4B39;
  --serif: "Iowan Old Style","Palatino Linotype",Palatino,Georgia,"Times New Roman",serif;
  --sans: "Helvetica Neue",Helvetica,Arial,"Segoe UI",Roboto,sans-serif;
  --r:3px;
}
*{box-sizing:border-box}
[hidden]{display:none!important}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.5 var(--sans)}
a{color:var(--green);text-underline-offset:3px}
h1,h2,h3{font-family:var(--serif);font-weight:400;letter-spacing:-.01em;line-height:1.15;margin:0 0 .4em}
h1{font-size:clamp(1.9rem,6vw,2.8rem)} h2{font-size:1.45rem} h3{font-size:1.1rem}
button,input,select,textarea{font:inherit;color:inherit}
:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
.skip{position:absolute;left:-999px}.skip:focus{left:8px;top:8px;background:#fff;padding:8px;z-index:9}
.masthead{border-bottom:1px solid var(--rule2);background:var(--paper);position:sticky;top:0;z-index:5}
.mast-inner{max-width:1040px;margin:auto;padding:12px 18px 0;display:flex;flex-wrap:wrap;align-items:baseline;gap:4px 24px}
.wordmark{font-family:var(--serif);font-size:1.6rem;color:var(--ink);text-decoration:none;letter-spacing:-.02em}
.nav{display:flex;gap:18px;overflow-x:auto;scrollbar-width:none;width:100%;padding-bottom:0}
@media(min-width:760px){.nav{width:auto}}
.nav a{color:var(--ink2);text-decoration:none;font-size:.92rem;padding:8px 0 10px;border-bottom:2px solid transparent;white-space:nowrap}
.nav a.active{color:var(--ink);border-bottom-color:var(--green)}
.offline{margin:0;background:var(--ink);color:var(--paper);font-size:.82rem;padding:6px 18px;text-align:center}
main{max-width:1040px;margin:auto;padding:22px 18px 40px;outline:none}
.foot{max-width:1040px;margin:auto;padding:18px;border-top:1px solid var(--rule);font-size:.8rem;color:var(--ink2)}
.page-head{border-bottom:1px solid var(--rule);padding-bottom:14px;margin-bottom:22px}
.dateline,.label,.qmeta{font-size:.74rem;text-transform:uppercase;letter-spacing:.09em;color:var(--ink2);margin:0 0 6px;font-weight:600}
.label.red,.tag.red{color:var(--red)}
.lede{color:var(--ink2);max-width:62ch;margin:.2em 0 0}
.meta{color:var(--ink2);font-size:.86rem}
.quiet{color:var(--ink2);font-size:.88rem}
.tag{font-size:.7rem;border:1px solid currentColor;border-radius:var(--r);padding:1px 5px;margin-left:6px;letter-spacing:.04em;text-transform:none}
.btn{display:inline-block;border:1px solid var(--ink);background:transparent;color:var(--ink);border-radius:var(--r);padding:10px 16px;text-decoration:none;cursor:pointer;font-size:.95rem;line-height:1.2}
.btn.primary{background:var(--green);border-color:var(--green);color:#fff}
.btn.red{background:var(--red);border-color:var(--red);color:#fff}
.btn.small{padding:5px 10px;font-size:.85rem}
.btn:hover{filter:brightness(1.08)}
.actions{display:flex;flex-wrap:wrap;gap:12px;align-items:center;margin:18px 0}
.actions.col{flex-direction:column;align-items:stretch}
.nba{border-left:3px solid var(--green);padding:4px 0 4px 16px;margin:0 0 30px}
.nba h2{font-size:1.7rem;margin-bottom:.2em}.nba p{margin:.2em 0 12px;color:var(--ink2);max-width:56ch}
.cols{display:grid;gap:30px}
@media(min-width:820px){.cols{grid-template-columns:1.5fr 1fr}.cols>aside{border-left:1px solid var(--rule);padding-left:26px}}
.section-head{display:flex;justify-content:space-between;align-items:baseline;border-bottom:1px solid var(--rule2);margin:22px 0 8px;padding-bottom:4px}
.section-head:first-child{margin-top:0}.section-head h2{font-size:1.2rem;margin:0}
h3.subj{font-family:var(--sans);font-size:.78rem;text-transform:uppercase;letter-spacing:.09em;color:var(--ink2);margin:16px 0 4px;font-weight:600}
.mastery{list-style:none;margin:0;padding:0}
.mastery a{display:grid;grid-template-columns:1fr auto 3.2em;gap:10px;align-items:center;padding:7px 0;border-bottom:1px solid var(--rule);text-decoration:none;color:var(--ink)}
.mastery .t{font-size:.95rem}.mastery .p{text-align:right;font-variant-numeric:tabular-nums;font-size:.9rem}
.p.low{color:var(--red)}.p.high{color:var(--green)}.p.none{color:var(--ink3)}
.cells{display:flex;gap:2px}.cells i{width:11px;height:11px;border:1px solid var(--ink2);display:block;font-style:normal;font-size:10px;line-height:9px;text-align:center;color:#fff}
.cells i.ok{background:var(--green);border-color:var(--green)}.cells i.bad{background:var(--red);border-color:var(--red)}
.leaks{margin:0;padding:0;list-style:none;counter-reset:l}
.leaks li{display:grid;grid-template-columns:1fr auto;padding:8px 0;border-bottom:1px solid var(--rule)}
.leaks .meta{grid-column:1}.leaks .lost{grid-row:1/3;grid-column:2;align-self:center}
.lost{color:var(--red);font-family:var(--serif);font-size:1.2rem;font-variant-numeric:tabular-nums}
.plain{list-style:none;padding:0;margin:0}.plain li{padding:8px 0;border-bottom:1px solid var(--rule)}
.list-rows{border-top:1px solid var(--rule2)}
.row-link{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:14px 0;border-bottom:1px solid var(--rule);text-decoration:none;color:var(--ink)}
.row-link strong{display:block;font-family:var(--serif);font-weight:400;font-size:1.15rem}
.row-link .go{color:var(--green);font-size:.9rem;white-space:nowrap}
.quiz{max-width:680px}
.stem{font-family:var(--serif);font-size:1.35rem;line-height:1.35;margin:.2em 0 18px}
.opts{list-style:none;padding:0;margin:0;border-top:1px solid var(--rule)}
.opt{display:flex;gap:14px;width:100%;text-align:left;background:none;border:0;border-bottom:1px solid var(--rule);padding:14px 4px;cursor:pointer;align-items:baseline;min-height:48px}
.opt:hover:not([disabled]){background:var(--paper2)}
.opt .k{font-weight:700;width:1.3em;color:var(--ink2)}
.opt.right{background:var(--green-tint)}.opt.right .k{color:var(--green)}
.opt.wrong{background:var(--red-tint)}.opt.wrong .t{text-decoration:line-through;text-decoration-color:var(--red);text-decoration-thickness:2px}
.opt.done{cursor:default;color:var(--ink)}
.opt .tagline{margin-left:auto;font-size:.78rem;font-weight:600;white-space:nowrap;padding-left:8px}
.opt.right .tagline{color:var(--green)}.opt.wrong .tagline{color:var(--red)}
.opt.sel{background:var(--paper2);box-shadow:inset 3px 0 0 var(--ink)}.opt.sel .k{color:var(--ink)}
.report{margin-top:18px}
.jump{border:1px solid var(--ink);background:#fff;padding:2px 8px;margin:2px;cursor:pointer}
.cbt-foot .quit{flex:0 0 auto;min-width:70px;background:#eceef0}

/* mobile tab bar: every page reachable at 390px */
.tabbar{display:none}
@media(max-width:759px){
  .nav{display:none}
  .tabbar{display:grid;grid-template-columns:repeat(5,1fr);position:fixed;left:0;right:0;bottom:0;z-index:15;background:var(--paper);border-top:1px solid var(--rule2);padding-bottom:env(safe-area-inset-bottom)}
  .tabbar a{text-align:center;padding:12px 2px 14px;font-size:.8rem;color:var(--ink2);text-decoration:none;border-top:2px solid transparent;min-height:48px}
  .tabbar a.active{color:var(--ink);border-top-color:var(--green);font-weight:600}
  body{padding-bottom:64px}
  body.exam-mode .tabbar{display:none}body.exam-mode{padding-bottom:0}
  .cookie{bottom:56px}
}
.feedback{margin-top:18px;padding-left:14px;border-left:3px solid var(--green)}
.feedback.is-wrong{border-left-color:var(--red)}
.verdict{font-family:var(--serif);font-size:1.25rem;margin:0 0 6px}
.is-wrong .verdict{color:var(--red)}
.trap,.working{margin:6px 0}.working .label,.trap .label{display:inline;margin-right:6px}
.byline{font-size:.75rem}
.repair-call{border:1px solid var(--red);border-radius:var(--r);padding:12px 14px;margin-top:16px}
.repair-call p{margin:0 0 10px}
.lesson .rule{font-family:var(--serif);font-size:1.2rem;line-height:1.45;border-left:3px solid var(--green);padding-left:14px;max-width:60ch}
s{text-decoration-color:var(--red);text-decoration-thickness:2px}
.ai-box{border-top:1px solid var(--rule);margin-top:18px;padding-top:10px;max-width:62ch}
.form{display:grid;gap:14px;max-width:460px}
.form.inline{max-width:none;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));align-items:end}
label{display:block;font-size:.82rem;color:var(--ink2);font-weight:600}
label.block{margin-bottom:6px}
input:not([type=checkbox]):not([type=radio]),select,textarea{display:block;width:100%;margin-top:4px;padding:10px;border:1px solid var(--rule-input);border-radius:var(--r);background:var(--sheet);font-weight:400;color:var(--ink)}
textarea{font-family:var(--serif);font-size:1.05rem;line-height:1.5}
label.check{display:flex;gap:8px;align-items:baseline;font-weight:400;color:var(--ink);font-size:.95rem;padding:6px 0}
.tbl{width:100%;border-collapse:collapse;margin:8px 0}.tbl th,.tbl td{border-bottom:1px solid var(--rule);padding:8px 6px;text-align:left;vertical-align:top;font-weight:400}
.tbl th{font-weight:400}.tbl td{font-variant-numeric:tabular-nums}.tbl .low{color:var(--red)}
.review{padding-left:1.4em}.review li{padding:8px 0;border-bottom:1px solid var(--rule)}.review li.x::marker{color:var(--red)}
.review p{margin:2px 0}
h1 .sub{font-size:.55em;color:var(--ink2)}
.flagline{border-left:3px solid var(--red);padding-left:10px;color:var(--ink);font-size:.9rem}
.marked{border-top:1px solid var(--rule2);margin-top:16px;padding-top:12px}
.log{display:grid;gap:10px;margin-bottom:14px}
.msg{max-width:62ch;padding:10px 0;border-bottom:1px solid var(--rule)}
.msg.me{font-family:var(--serif);font-size:1.1rem}
.msg.bot p{margin:0 0 4px}
.ask{display:flex;gap:8px;position:sticky;bottom:0;background:var(--paper);padding:10px 0}.ask input{margin:0}
.leak-wrap{display:grid;gap:24px}
@media(min-width:820px){.leak-wrap{grid-template-columns:420px 1fr}}
#card{width:100%;height:auto;border:1px solid var(--rule2)}
.heat-scroll{overflow-x:auto;border:1px solid var(--rule)}
.heat{border-collapse:collapse;font-size:.78rem;font-variant-numeric:tabular-nums}
.heat th{font-weight:400;text-align:left;padding:4px 8px;white-space:nowrap;background:var(--paper)}
.heat thead th{height:120px;vertical-align:bottom}.heat thead th span{writing-mode:vertical-rl;transform:rotate(180deg)}
.heat tbody th{position:sticky;left:0}
.heat td{width:36px;height:30px;text-align:center;border:1px solid var(--paper);
  background:color-mix(in srgb,var(--red) calc((1 - var(--p)) * 60%),#fffdf8);color:var(--ink)}
.heat td.na{background:repeating-linear-gradient(45deg,transparent 0 3px,var(--rule) 3px 4px)}
.draft{border:1px solid var(--rule2);padding:14px;border-radius:var(--r);display:grid;gap:10px;margin:12px 0}
.optrow{display:grid;grid-template-columns:2fr 1.4fr;gap:8px}
section{margin-bottom:28px}
.toast{position:fixed;left:50%;transform:translateX(-50%);bottom:18px;background:var(--ink);color:var(--paper);padding:10px 16px;border-radius:var(--r);font-size:.9rem;z-index:20;max-width:90vw}
details summary{cursor:pointer;color:var(--green);font-size:.9rem;margin:8px 0}
.file{cursor:pointer}

/* ---------- CBT exam hall: deliberately plain, like the real screen ---------- */
body.exam-mode .masthead,body.exam-mode .foot{display:none}
body.exam-mode main{max-width:none;padding:0}
.cbt{min-height:100vh;display:flex;flex-direction:column;background:#eceef0;color:#111;font-family:Arial,Helvetica,sans-serif}
.cbt-bar{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;background:#1f2a33;color:#fff;padding:10px 14px;font-size:.85rem}
.timer{font-variant-numeric:tabular-nums;font-weight:700;background:#fff;color:#111;padding:2px 8px}
.timer.low{background:var(--amber);color:#fff}
.cbt-body{flex:1;display:grid;gap:12px;padding:12px}
@media(min-width:820px){.cbt-body{grid-template-columns:1fr 260px}}
.cbt-q{background:#fff;border:1px solid #b9bec4;padding:16px}
.cbt-q .qn{font-size:.82rem;color:#444;margin:0 0 8px}
.cbt-q .stem{font-family:Arial,Helvetica,sans-serif;font-size:1.1rem}
.copt{display:flex;gap:8px;align-items:baseline;padding:10px 6px;border-top:1px solid #e1e3e6;font-weight:400;color:#111;font-size:1rem;cursor:pointer}
.copt input{width:18px;height:18px}
.palette{background:#fff;border:1px solid #b9bec4;padding:10px}
#pal{display:grid;grid-template-columns:repeat(auto-fill,minmax(38px,1fr));gap:4px}
#pal button,.legend i{border:1px solid #8a9096;background:#fff;height:34px;font-size:.85rem;cursor:pointer}
#pal button.a,.legend i.a{background:#2f6b4f;color:#fff;border-color:#2f6b4f}
#pal button.f,.legend i.f{box-shadow:inset 0 -4px 0 #d08b00}
#pal button.cur{outline:2px solid #111;outline-offset:1px}
.legend i{display:inline-block;width:12px;height:12px;vertical-align:middle;margin:0 4px 0 8px}
.cbt-foot{display:flex;gap:8px;padding:10px 12px;background:#d9dde1;flex-wrap:wrap}
.cbt-foot button{flex:1;min-width:110px;padding:12px;border:1px solid #6b7178;background:#fff;cursor:pointer}
.cbt-foot .sub{background:#1f2a33;color:#fff}
.confirm{position:fixed;inset:0;background:rgba(0,0,0,.45);display:grid;place-items:center;padding:16px}
.confirm>div{background:#fff;padding:20px;max-width:380px;border:1px solid #333;max-height:calc(100dvh - 32px);overflow-y:auto;overscroll-behavior:contain}
.confirm .cf-actions{position:sticky;bottom:-20px;background:#fff;padding:12px 0 0;margin-top:8px;border-top:1px solid #ddd}
.confirm #cf-p{max-height:none}
.confirm h2{font-family:Arial,sans-serif;font-size:1.2rem}
.confirm button{padding:10px 14px;border:1px solid #333;background:#fff;cursor:pointer}#yes{background:#1f2a33;color:#fff}

/* ---------- social / growth ---------- */
.btn.wa{background:var(--green);border-color:var(--green);color:#fff}
.sheet{display:grid;gap:12px;max-width:560px}
.fmt{display:flex;flex-wrap:wrap;gap:0;border:1px solid var(--ink);border-radius:var(--r);overflow:hidden;width:max-content;max-width:100%}
.fmt button{background:none;border:0;border-right:1px solid var(--ink);padding:8px 12px;cursor:pointer;font-size:.85rem}
.fmt button:last-child{border-right:0}.fmt button[aria-selected=true]{background:var(--ink);color:var(--paper)}
.fmt.types{margin-bottom:14px}
.cardc{width:100%;max-height:70vh;object-fit:contain;border:1px solid var(--rule2);background:var(--paper)}
.targets{display:grid;grid-template-columns:repeat(auto-fill,minmax(120px,1fr));gap:8px}.targets .btn{text-align:center}
.strip{display:flex;flex-wrap:wrap;gap:6px 18px;border-top:1px solid var(--rule2);border-bottom:1px solid var(--rule);padding:10px 0;margin:-10px 0 24px;font-size:.9rem}
.strip a{color:var(--ink);text-decoration:none}.strip .n{font-family:var(--serif);font-size:1.3rem;color:var(--green)}
.strip .wa-link{color:var(--green);text-decoration:underline}
.savehint{margin:-12px 0 20px}
.saveprompt{border:1px solid var(--green);border-radius:var(--r);padding:14px 16px}
.refack{border-top:1px solid var(--rule2);padding-top:10px}
.as-btn{width:100%;background:none;border:0;border-bottom:1px solid var(--rule);font:inherit;text-align:left;cursor:pointer}
.buddy{border-left:3px solid var(--green);padding-left:12px}
fieldset{border:1px solid var(--rule);border-radius:var(--r);padding:8px 12px}legend{font-size:.82rem;color:var(--ink2);font-weight:600}
.guardian{border-left:3px solid var(--red);padding-left:12px}
.notice{border-top:1px solid var(--rule);padding-top:6px;font-size:.9rem}.notice ul{padding-left:1.2em;margin:4px 0}
.err{color:var(--red);min-height:1.2em;margin:0}
.bigcode{font-family:var(--serif);font-size:3rem;letter-spacing:.2em}
.first{margin-bottom:12px}
.cookie{position:fixed;left:0;right:0;bottom:0;background:var(--paper);border-top:2px solid var(--ink);padding:12px 18px;z-index:30;font-size:.9rem}
.cookie p{margin:0 auto;max-width:1040px}.cookie .actions{max-width:1040px;margin:8px auto 0}
.others{margin-top:10px;border-top:1px solid var(--rule);padding-top:8px;font-size:.92rem}
.others summary{cursor:pointer;color:var(--green);font-weight:600}
.others ul{margin:8px 0 0;padding-left:18px}.others li{margin:4px 0;color:var(--ink2)}
.review .working,.review .trap{font-size:.92rem}
.review .others li{border:0;padding:0;margin:4px 0}
.cells{flex-wrap:wrap;align-items:center;max-width:62vw}.cells .cov{font-size:.75rem;color:var(--ink3);margin-left:4px;font-variant-numeric:tabular-nums}
.mastery a>*{min-width:0}
/* v2.6.x backend pages: teacher review, account, legal */
.review-opts .opt{cursor:default}.review-opts .opt.key{background:var(--green-tint)}.review-opts .opt.key .k{color:var(--green)}
.doc h2{margin-top:1.6em}.doc table{border-collapse:collapse;width:100%}.doc td,.doc th{border-bottom:1px solid var(--rule);padding:6px 4px;text-align:left;vertical-align:top}
.ph{background:var(--paper2);padding:0 3px;font-family:ui-monospace,monospace;font-size:.92em}
#main{min-height:calc(100vh - 140px)} /* reserve space so the footer doesn't jump when the view renders (CLS) */
.rv-stage{min-height:100vh}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.theory-group summary h2{display:inline;font-size:1.05rem;margin:0;color:var(--ink,inherit)}.theory-group{border-top:1px solid rgba(0,0,0,.08);padding:4px 0}
h1.label{line-height:1.3}
/* Focused practice desk: compact choices and readable subject progress. */
.practice-grid,.coverage-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;margin:22px 0 30px}
.practice-grid .row-link,.coverage-card{min-width:0;border:1px solid var(--rule);border-radius:9px;background:var(--sheet);padding:21px;align-items:flex-start}
.practice-grid .row-link:hover{border-color:var(--green);background:var(--green-tint)}
.practice-grid .row-link strong{font-size:1.3rem;margin-bottom:7px}.practice-grid .row-link .meta{display:block}
.coverage-card h2{font-size:1.25rem}.coverage-card p{margin:9px 0 0}
.foundation{padding:24px;background:var(--green-tint);border:1px solid var(--rule);border-radius:9px;margin:26px 0}
.foundation .actions{margin-bottom:0}.foundation .btn{background:var(--paper)}
.nba{border:1px solid var(--rule);border-left:4px solid var(--green);border-radius:8px;background:var(--green-tint);padding:24px}
.subject-progress{border-bottom:1px solid var(--rule);padding:12px 0}.subject-progress>summary{cursor:pointer;display:flex;justify-content:space-between;gap:12px;align-items:center;font-family:var(--serif);font-size:1.14rem;min-height:44px}
.subject-progress>summary:before{content:'+';color:var(--green);font-family:var(--sans)}.subject-progress[open]>summary:before{content:'−'}
.subject-progress>summary span:first-of-type{flex:1}.subject-progress .mastery{padding:8px 0}
.question-report{margin-top:24px;border-top:1px solid var(--rule);padding-top:12px;color:var(--ink2);font-size:.9rem}
.question-report summary{cursor:pointer;min-height:44px;padding:10px 0}.question-report textarea{width:100%}
@media(max-width:600px){.practice-grid,.coverage-grid{grid-template-columns:1fr}.practice-grid .row-link,.coverage-card{padding:18px}.foundation,.nba{padding:20px}.subject-progress>summary{flex-wrap:wrap}.subject-progress>summary .meta{font-size:.75rem}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
/* Sabi 2.9. Book typography, a useful desk, and the quiet details of a revision notebook. */
@font-face{font-family:Sabi Book;src:url('fonts/Book.woff') format('woff');font-style:normal;font-weight:400;font-display:swap}
@font-face{font-family:Sabi Book;src:url('fonts/Book-Italic.woff') format('woff');font-style:italic;font-weight:400;font-display:swap}
@font-face{font-family:Sabi Text;src:url('fonts/Text.woff') format('woff');font-style:normal;font-weight:400;font-display:swap}
@font-face{font-family:Sabi Text;src:url('fonts/Text-Bold.woff') format('woff');font-style:normal;font-weight:600 800;font-display:swap}
:root{--paper:#f8f6ef;--paper2:#efede3;--sheet:#fffefa;--ink:#242c28;--ink2:#505b54;--ink3:#667068;--rule:#d7d9cd;--rule2:#253e32;--green:#244d3d;--green-tint:#e9ede4;--red:#9b4537;--red-tint:#f8ece7;--serif:'Sabi Book',Georgia,serif;--sans:'Sabi Text',Arial,sans-serif;--r:3px}
body{font-size:16px;line-height:1.55}h1,h2,h3{font-family:var(--serif);font-weight:400;letter-spacing:-.035em}h1{font-size:clamp(2.5rem,5vw,3.8rem);line-height:1.05}h2{font-size:1.85rem}p{max-width:75ch}a,button{touch-action:manipulation}
.masthead{background:var(--paper);border-bottom:1px solid var(--rule);position:relative}
.mast-inner{max-width:1240px;min-height:94px;padding:18px 40px;gap:0 26px;align-items:center;flex-wrap:nowrap}
.wordmark{font-family:var(--serif);font-size:2.7rem;font-style:italic;color:var(--green);line-height:1;text-decoration:none;letter-spacing:-.07em;padding-right:5px}
.brand-aside{font-size:.78rem;line-height:1.3;color:var(--ink2);max-width:90px;border-left:1px solid var(--rule);padding-left:19px}
.nav{margin-left:auto;width:auto;gap:25px;overflow:visible}.nav a{font-size:.91rem;padding:12px 0;color:var(--ink2)}.nav a.active{border-color:var(--red);color:var(--ink)}
main{max-width:1160px;padding:44px 40px 64px;min-height:68vh}.page-head{margin-bottom:32px;padding-bottom:26px}.page-head .lede{margin-top:14px;max-width:66ch}
.label,.dateline{font-family:var(--sans);font-size:.7rem;letter-spacing:.13em;font-weight:600;color:var(--ink2)}
.btn{border-radius:3px;padding:13px 20px;font-size:.94rem;min-height:46px;display:inline-flex;align-items:center;justify-content:center;gap:24px}.btn.primary{background:var(--green);border-color:var(--green)}.btn:hover{filter:none;background:var(--paper2)}.btn.primary:hover{background:#193b2d}.btn.red:hover{background:#7b3229}.text-link{font-size:.9rem;color:var(--green);text-decoration:none;display:inline-flex;gap:12px;align-items:center;min-height:44px;border-bottom:1px solid transparent}.text-link:hover{border-bottom-color:var(--green)}
.desk-heading{padding:0 0 31px}.desk-heading .dateline{display:flex;justify-content:space-between;align-items:center;margin:0 0 27px}.desk-heading .dateline span{font-weight:400;letter-spacing:.08em}.desk-heading h1{font-size:clamp(2.7rem,5.8vw,4.8rem);margin:0;line-height:1.05}.desk-intro{margin:14px 0 0;color:var(--ink2);font-size:1.08rem;max-width:62ch}
.desk-top{display:grid;grid-template-columns:minmax(0,1.9fr) minmax(235px,1fr);gap:44px;align-items:stretch;margin:10px 0 55px}
.session-sheet.nba{position:relative;margin:0;background:var(--sheet);border:1px solid var(--rule);border-top:3px solid var(--green);border-radius:0;padding:24px 32px 20px;box-shadow:4px 5px 0 -1px var(--paper2),4px 5px 0 0 var(--rule)}
.sheet-top{display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--rule);padding-bottom:13px;margin-bottom:23px}.sheet-top .label{margin:0}.sheet-number{font-size:.76rem;color:var(--ink3);font-variant-numeric:tabular-nums}.session-sheet h2{font-size:clamp(2rem,3.7vw,3.1rem);line-height:1.07;max-width:470px;margin:0 0 17px;letter-spacing:-.035em}.session-sheet p{max-width:48ch;font-size:.95rem;line-height:1.65}.session-sheet .actions{gap:22px;margin:23px 0 19px}.session-sheet .sheet-note{font-family:var(--serif);font-style:italic;font-size:.89rem;color:var(--ink3);border-top:1px solid var(--rule);padding-top:13px;max-width:none;margin-bottom:0}
.week-note{border-top:1px solid var(--rule2);padding-top:17px}.week-note>.label{margin:0 0 21px}.week-total{display:flex;align-items:center;gap:15px;min-height:58px}.week-total>strong{font-family:var(--serif);font-size:3.4rem;line-height:1;font-weight:400;letter-spacing:-.05em}.week-total>span{font-size:.87rem;color:var(--ink2);max-width:150px;line-height:1.4}.week-bars{display:grid;grid-template-columns:repeat(7,1fr);gap:12px;margin:25px 0 23px;max-width:100%;height:102px}.week-day{display:flex;flex-direction:column;text-align:center;gap:9px;color:var(--ink3);font-size:.72rem}.bar-track{height:76px;display:flex;align-items:flex-end;border-bottom:1px solid var(--rule);background:linear-gradient(to bottom,transparent calc(50% - .5px),var(--rule) 50%,transparent calc(50% + .5px))}.bar-track>span{display:block;width:100%;max-width:23px;margin:auto auto 0;background:#b6c2b4;min-height:2px}.is-today .bar-track>span{background:var(--red)}.is-today>span{color:var(--red);font-weight:600}.review-link{display:flex;justify-content:space-between;gap:10px;border-top:1px solid var(--rule);border-bottom:1px solid var(--rule);padding:13px 0;text-decoration:none;font-size:.82rem;color:var(--ink2)}.review-link strong{font-weight:400;color:var(--green);white-space:nowrap}.exam-date{display:inline-block;color:var(--ink3);font-size:.8rem;margin-top:14px;text-decoration:none}
.desk-section-head{display:flex;justify-content:space-between;align-items:flex-end;gap:20px;border-bottom:1px solid var(--rule2);padding-bottom:16px;margin-bottom:0}.desk-section-head h2{margin:0}.desk-section-head .label{margin-bottom:8px}.desk-section-head .text-link{min-height:28px}.subject-directory{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));column-gap:44px}.subject-entry{display:flex;align-items:center;gap:17px;min-height:102px;border-bottom:1px solid var(--rule);text-decoration:none;color:var(--ink);padding:19px 3px}.subject-entry:hover{background:var(--paper2)}.subject-initial{align-self:stretch;min-width:47px;display:flex;align-items:center;justify-content:center;border-left:2px solid #8eaa9a;font-family:var(--serif);font-size:1.5rem;font-style:italic;color:var(--green);letter-spacing:-.05em}.subject-entry:nth-child(3n+2) .subject-initial{border-left-color:#b9816b;color:#875440}.subject-entry:nth-child(3n) .subject-initial{border-left-color:#a0a884;color:#626b48}.subject-text{min-width:0;flex:1}.subject-text strong{display:block;font-family:var(--serif);font-size:1.35rem;font-weight:400;line-height:1.2;margin-bottom:6px}.subject-text .meta{display:block;font-size:.77rem}.entry-arrow{font-size:1.15rem;color:var(--green);margin-right:6px}
.desk-bottom{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:44px;margin-top:44px;padding:28px 0;border-top:1px solid var(--rule2);border-bottom:1px solid var(--rule)}.desk-bottom h2{font-size:1.8rem;margin:12px 0}.desk-bottom p:not(.label){font-size:.9rem;color:var(--ink2);max-width:44ch;margin:0 0 10px}.editorial-note{font-size:.78rem;color:var(--ink3);margin:27px 0 0;max-width:none}.editorial-note a{color:inherit}.progress-notes{margin-top:35px}.progress-notes h2{font-size:1.6rem}.recent-line{display:flex;justify-content:space-between;gap:15px;border-bottom:1px solid var(--rule);padding:13px 0;max-width:none}
.practice-tools{display:flex;justify-content:space-between;gap:20px;align-items:center;margin-bottom:18px}.subject-search{flex:1;max-width:380px}.subject-search input{width:100%;border:0;border-bottom:1px solid var(--rule-input);background:transparent;padding:14px 0;font:inherit;border-radius:0;min-height:48px}.mode-switch{display:flex;border:1px solid var(--rule-input);padding:3px;border-radius:3px;gap:3px}.mode-switch button{background:none;border:0;padding:10px 12px;font-size:.83rem;cursor:pointer;min-height:44px;border-radius:1px}.mode-switch button[aria-pressed=true]{background:var(--green);color:var(--sheet)}.practice-extras{margin:38px 0 0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:44px;border-top:1px solid var(--rule2);padding-top:23px}.practice-extras>a{display:flex;flex-direction:column;gap:8px;text-decoration:none;color:var(--ink)}.practice-extras strong{font-family:var(--serif);font-size:1.5rem;font-weight:400}.practice-extras strong span{font-family:var(--sans);font-size:1rem;color:var(--green)}
.quiz{max-width:760px;margin:0 auto}.quiz-topline{display:flex;justify-content:space-between;gap:20px;margin:0 0 22px;align-items:center}.quiz .label{margin:0 0 10px}.quiz-progress{width:100%;height:3px;display:block;appearance:none;border:0;background:var(--rule);margin:0 0 33px;accent-color:var(--green)}.quiz-progress::-webkit-progress-bar{background:var(--rule)}.quiz-progress::-webkit-progress-value{background:var(--green)}.quiz .stem{font-size:clamp(1.5rem,3vw,2rem);line-height:1.35;margin:10px 0 27px;letter-spacing:-.015em}.quiz .qmeta{font-size:.71rem}.quiz .opt{border:1px solid var(--rule);background:var(--sheet);border-radius:3px;margin-bottom:10px;padding:16px 18px;align-items:center;gap:17px;min-height:62px}.quiz .opts{border:0}.quiz .opt .k{font-family:var(--serif);font-weight:400;font-size:1.15rem;border-right:1px solid var(--rule);padding-right:15px;width:34px;flex-shrink:0}.quiz .opt.right{background:var(--green-tint);border-color:#879f8e}.quiz .opt.wrong{background:var(--red-tint);border-color:#c79587}.quiz .opt:hover:not(.done){border-color:var(--green);background:var(--green-tint)}.quiz .feedback{padding:22px 24px;margin:26px 0;border-left:3px solid var(--green);background:var(--sheet)}.quiz .feedback.is-wrong{border-left-color:var(--red)}.quiz .verdict{font-family:var(--serif);font-size:1.6rem}.quiz .working{font-size:.95rem;line-height:1.7}.quiz .byline{border-top:1px solid var(--rule);padding-top:12px;font-size:.75rem}
.theory-group{border-bottom:1px solid var(--rule);padding:13px 0}.theory-group>summary{cursor:pointer;padding:8px 0}.theory-group>summary h2{display:inline;font-size:1.5rem}.theory-search{display:block;max-width:520px;margin-bottom:25px}.theory-search input{width:100%;border:1px solid var(--rule-input);padding:12px 15px;border-radius:2px;background:var(--sheet)}
.form input:not([type=checkbox]):not([type=radio]),.form select,.form textarea,textarea{background:var(--sheet);border-radius:2px}select,input,textarea{max-width:100%}.form label{font-size:.9rem}.foundation,.coverage-card,.practice-grid .row-link{border-radius:2px}.coverage-card{background:transparent}.coverage-grid{gap:0 30px}.coverage-card{border:0;border-bottom:1px solid var(--rule);padding:20px 0}.foot{max-width:1160px;padding:22px 40px 30px;border-top:1px solid var(--rule);font-size:.73rem;line-height:1.8;color:var(--ink3)}.foot a{color:inherit}.cookie{left:auto;right:24px;bottom:24px;max-width:470px;border:1px solid var(--rule2);padding:20px 24px;background:var(--sheet);box-shadow:0 4px 20px #242c2812;font-size:.82rem}.cookie .actions{gap:12px;margin:17px 0 0}.cookie .btn{font-size:.83rem;min-height:44px;padding:11px 14px}.toast{max-width:calc(100vw - 32px);font-size:.87rem}
@media(min-width:1100px){main{padding-top:51px}.desk-heading .dateline{margin-bottom:32px}.desk-top{margin-top:13px}}
@media(max-width:900px){.mast-inner{padding:18px 26px;gap:20px}.brand-aside{display:none}.nav{gap:20px}.desk-top{gap:28px;grid-template-columns:minmax(0,1.55fr) minmax(220px,1fr)}main{padding:34px 26px 52px}.session-sheet.nba{padding:23px}.subject-directory,.desk-bottom,.practice-extras{column-gap:28px}.subject-text strong{font-size:1.2rem}.practice-tools{align-items:stretch;flex-direction:column}.subject-search{max-width:none}.mode-switch{align-self:flex-start}}
@media(max-width:759px){body{padding-bottom:68px}.mast-inner{min-height:76px;padding:16px 22px}.wordmark{font-size:2.3rem}.brand-aside{display:block;margin-left:auto;max-width:none;border:0;padding:0;font-size:.75rem}.nav{display:none}.tabbar{display:grid;background:var(--paper);border-top:1px solid var(--rule2);z-index:15}.tabbar a{min-height:58px;font-size:.76rem;padding:17px 3px 13px;border-top:2px solid transparent}.tabbar a.active{border-top-color:var(--red)}main{padding:27px 22px 42px}.desk-heading{padding-bottom:27px}.desk-heading .dateline{font-size:.64rem;letter-spacing:.08em;gap:10px;margin-bottom:25px}.desk-heading .dateline span{letter-spacing:0}.desk-heading h1{font-size:3.05rem}.desk-intro{font-size:.98rem;max-width:34ch}.desk-top{grid-template-columns:1fr;gap:31px;margin:0 0 36px}.session-sheet.nba{padding:21px 23px}.session-sheet h2{font-size:2.55rem}.session-sheet p{font-size:.91rem}.session-sheet .actions{gap:12px 20px}.session-sheet .sheet-note{font-size:.8rem}.week-note{padding-top:19px}.week-note>.label{margin-bottom:14px}.week-total>strong{font-size:2.7rem}.week-total>span{max-width:none}.week-total{min-height:42px}.week-bars{height:76px;margin:17px 0 20px;gap:18px}.bar-track{height:54px}.review-link{font-size:.85rem}.exam-date{margin-top:13px}.desk-section-head{padding-bottom:13px}.desk-section-head h2{font-size:1.7rem}.desk-section-head .text-link{font-size:.78rem;white-space:nowrap}.subject-directory{grid-template-columns:1fr}.subject-entry{min-height:92px;padding:17px 0}.subject-text strong{font-size:1.35rem}.subject-text .meta{font-size:.77rem}.desk-bottom{grid-template-columns:1fr;gap:25px;margin-top:32px;padding-top:25px}.desk-bottom>section+section{border-top:1px solid var(--rule);padding-top:24px}.desk-bottom h2{font-size:1.9rem}.practice-extras{grid-template-columns:1fr;gap:24px}.practice-extras>a+ a{border-top:1px solid var(--rule);padding-top:20px}.page-head h1{font-size:2.8rem}.page-head .lede{font-size:.95rem}.mode-switch{width:100%;justify-content:stretch}.mode-switch button{flex:1;font-size:.81rem;padding:10px}.quiz .opt{padding:14px 13px;gap:13px;flex-wrap:wrap}.quiz .opt .t{flex:1;min-width:0}.quiz .opt .tagline{width:100%;margin-left:47px;white-space:normal;padding:0;text-align:left}.quiz .opt .tagline:empty{display:none}.quiz .feedback{padding:18px}.quiz .stem{font-size:1.7rem}.foot{padding:21px 22px 26px}.cookie{left:12px;right:12px;bottom:76px;max-width:none;padding:17px 18px}.coverage-grid{grid-template-columns:1fr}.recent-line{flex-wrap:wrap}.editorial-note{font-size:.75rem}.brand-aside{white-space:nowrap}.desk-bottom .text-link{min-height:44px}}
@media(max-width:360px){main{padding-left:17px;padding-right:17px}.desk-heading h1{font-size:2.65rem}.session-sheet.nba{padding:19px}.session-sheet h2{font-size:2.3rem}.desk-heading .dateline span{display:none}.desk-section-head h2{font-size:1.5rem}.subject-text strong{font-size:1.25rem}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
.desk-heading .dateline{max-width:none}
/* Useful revision tools, kept in the same notebook vocabulary. */
.offline-home{border-top:1px solid var(--rule);padding-top:22px;margin:28px 0 0;max-width:none}.offline-home>a{font-size:.9rem;text-decoration:none}.offline-home>.meta{display:block;margin-top:5px;font-size:.78rem}.offline-directory{border-top:1px solid var(--rule2)}.offline-subject{display:flex;justify-content:space-between;gap:24px;align-items:center;padding:23px 0;border-bottom:1px solid var(--rule)}.offline-subject h2{font-size:1.5rem;margin-bottom:4px}.offline-subject p{margin:5px 0 0}.offline-subject .btn{flex-shrink:0;min-width:132px}.offline-subject .btn:disabled{color:var(--ink3);border-color:var(--rule);cursor:default;background:var(--paper2)}.download-state{color:var(--green)}.mistake-subject{margin-bottom:32px}.mistake-item{border-bottom:1px solid var(--rule);padding:16px 0}.mistake-item summary{cursor:pointer;line-height:1.5}.mistake-item summary>span:first-child{font-family:var(--serif);font-size:1.15rem}.mistake-item summary>.meta{display:block;margin:5px 0 0 17px}.mistake-item>p{padding-left:17px}.draft-state{border-left:2px solid var(--green);padding-left:12px;font-size:.8rem;margin:13px 0 20px}
@media(max-width:600px){.offline-subject{align-items:flex-start;gap:14px;flex-direction:column}.offline-subject .btn{min-width:0;align-self:stretch}.mistake-subject .desk-section-head h2{font-size:1.35rem}}
.backup-restore{padding:22px 0;margin:23px 0;border-top:1px solid var(--rule);border-bottom:1px solid var(--rule)}.backup-restore h3{font-size:1.5rem}.backup-restore #restore-preview{font-size:.87rem;margin-top:17px}
.backup-file{display:block;font-size:.9rem;margin:15px 0}.backup-file input{display:block;margin-top:9px;width:100%;max-width:500px;min-height:44px}

/* The longer GradeRadar wordmark stays readable on compact screens. */
@media(min-width:760px) and (max-width:1100px){.brand-aside{display:none}.mast-inner{gap:18px}.nav{gap:18px}}
@media(max-width:420px){.wordmark{font-size:1.9rem;letter-spacing:-.055em}.brand-aside{font-size:.65rem;max-width:80px;white-space:normal}.mast-inner{gap:10px}}