[class="brand-symbol"]{width:42px;height:42px;border-radius:8px;font-size:15px;letter-spacing:.04em;box-shadow:inset 0 -5px 0 #0d4b40,0 4px 0 #d99b34}
.brand-symbol b{font-weight:800;position:relative;z-index:1}
.brand-sparks{position:absolute;right:3px;top:-10px;color:#e4a634;font-size:15px;line-height:1}
.brand-sparks:after{content:'';position:absolute;width:4px;height:4px;border-radius:50%;background:#f5c45d;right:-5px;top:11px;box-shadow:6px -4px 0 #d99b34}
.topic-button{display:grid;grid-template-columns:24px minmax(0,1fr) auto;align-items:center}
.topic-icon{width:22px;height:22px;display:grid;place-items:center;border:1px solid #c9d8d2;border-radius:5px;color:var(--green);font-size:14px;font-weight:700;line-height:1}
.topic-name{min-width:0}
.topic-button .topic-icon{box-sizing:border-box;flex:none;align-self:center;justify-self:start;font-family:"Segoe UI Symbol","Noto Sans Symbols",sans-serif;font-size:13px;line-height:22px;text-align:center;overflow:hidden}
.topic-button .topic-name{align-self:center;line-height:1.35}
.topic-button .topic-name{justify-self:stretch;text-align:left}
:root{font-family:Inter,Arial,sans-serif;color:#202d30;background:#f5f7f7;font-synthesis:none;--green:#156b59;--line:#dce3e2}html[data-palette=amber]{--green:#9d5d2d}html[data-palette=ocean]{--green:#0d5d92}html[data-palette=violet]{--green:#5a4a9a}html[data-theme=dark]{--green:#76d6b1}html[data-theme=dark][data-palette=amber]{--green:#f0b36a}html[data-theme=dark][data-palette=ocean]{--green:#8ec9ff}html[data-theme=dark][data-palette=violet]{--green:#b8a4ff}*{box-sizing:border-box;letter-spacing:0}body{margin:0}button,input,textarea{font:inherit}button,a,input,textarea{ -webkit-tap-highlight-color:transparent}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible,textarea:focus-visible{outline:3px solid #d99b34;outline-offset:3px}.theme-picker{position:relative}.theme-palette-button{display:inline-flex;align-items:center;gap:8px}.theme-palette-dot{display:inline-block;width:12px;height:12px;border-radius:50%;background:var(--green);box-shadow:0 0 0 2px rgba(255,255,255,.7),0 0 8px rgba(21,107,89,.25)}.theme-palette-menu{position:absolute;top:calc(100% + 6px);right:0;display:grid;gap:6px;padding:8px;min-width:156px;border:1px solid var(--line);border-radius:12px;background:rgba(255,255,255,.96);box-shadow:0 18px 36px rgba(18,61,54,.08),0 0 0 1px rgba(255,255,255,.7) inset;z-index:20}.palette-option{display:flex;align-items:center;gap:8px;width:100%;border:1px solid transparent;border-radius:8px;background:transparent;padding:8px 10px;color:inherit;text-align:left}.palette-option.active{background:#edf6f2;border-color:#cfe2d8}.palette-pill{display:inline-block;width:12px;height:12px;border-radius:50%}.palette-pill.forge{background:#156b59}.palette-pill.amber{background:#9d5d2d}.palette-pill.ocean{background:#0d5d92}.palette-pill.violet{background:#5a4a9a}header{height:86px;background:white;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 40px}.brand{display:flex;gap:12px;align-items:center;font-weight:750;font-size:21px;text-decoration:none;color:inherit}.brand-symbol{background:var(--green);color:white;width:38px;height:38px;border-radius:7px;display:grid;place-content:center;position:relative;font-size:26px}.brand-symbol span{position:absolute;right:3px;top:0;font-size:14px}.course{font-size:12px;color:#5e7073}.course b{border-left:1px solid var(--line);margin-left:12px;padding-left:12px}.layout{display:grid;grid-template-columns:264px 1fr;min-height:calc(100vh - 86px)}aside{background:#fff;border-right:1px solid var(--line);padding:32px 18px}.section-label{font-size:11px;font-weight:700;color:#6a7b7b;letter-spacing:0}aside>.section-label,aside>h2{margin-left:14px}h2{font-size:19px;margin:10px 0 20px}.topic-button{display:flex;align-items:center;justify-content:space-between;gap:8px;width:100%;border:0;background:none;text-align:left;padding:12px 14px;border-radius:5px;color:#536265;font-size:13px;line-height:1.45}.topic-button:hover{background:#f3f6f5}.topic-button.active{background:#e6f2ed;color:#155d4d;font-weight:700}.topic-button small{font-size:11px;flex-shrink:0;opacity:.7}.topic-group{font-size:10px;color:#82908e;padding:24px 14px 8px}.aside-note{font-size:11px;color:#82908e;line-height:1.7;padding:28px 14px}main{padding:38px 44px;min-width:0;max-width:1600px;width:100%;margin:auto}.heading{display:flex;align-items:center;justify-content:space-between;margin-bottom:32px;gap:20px}h1{font-size:34px;line-height:1.23;font-weight:600;margin:12px 0 0}.progress-summary{border-left:1px solid var(--line);padding:8px 0 8px 28px;display:flex;flex-direction:column;gap:7px;font-size:12px;color:#637572}.progress-summary strong{font-size:32px;color:var(--green)}.text-button{border:0;background:none;padding:4px 0;text-align:left;color:#667773;font-size:11px;text-decoration:underline}.controls{border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:22px 0;display:flex;gap:24px;align-items:end;flex-wrap:wrap}.controls label,.controls legend{font-size:12px;color:#5b6b6a;margin-bottom:9px;display:block}.controls input[type=search]{background:white;border:1px solid #ccd6d3;border-radius:5px;padding:11px 12px;width:220px}.controls fieldset{border:0;margin:0;padding:0;min-width:0}.segmented{display:flex;border:1px solid #ccd6d3;border-radius:5px;background:white;padding:3px;gap:2px}.segmented button{border:0;padding:9px 12px;font-size:12px;background:transparent;color:#5c6e69;border-radius:3px}.segmented button[aria-pressed=true]{background:var(--green);color:#fff}.controls label.toggle{display:flex;align-items:center;gap:7px;min-height:40px;margin-bottom:0}input[type=checkbox]{accent-color:var(--green)}.workspace-heading{display:flex;justify-content:space-between;align-items:center;padding:28px 0 20px;gap:12px}.workspace-heading h2{margin:0}.workspace-heading>span{font-size:12px;color:#6a7b7b}.practice-layout{display:grid;grid-template-columns:240px minmax(0,1fr);gap:28px;align-items:start}#question-list{display:flex;flex-direction:column;gap:8px;max-height:640px;overflow:auto;padding:2px}.question-link{border:1px solid var(--line);background:#fff;text-align:left;padding:16px;border-radius:6px;min-height:94px;color:inherit}.question-link.active{border-color:var(--green);background:#edf5f1;box-shadow:inset 3px 0 var(--green)}.question-link strong{display:block;font-size:13px;margin:9px 0;line-height:1.45}.question-link small{font-size:10px;color:#6e807c}.question-link .mini-meta{display:flex;justify-content:space-between;font-size:10px;color:#6e807c}.question-sheet{background:white;border:1px solid var(--line);border-radius:7px;padding:30px;min-height:540px}.question-top{display:flex;justify-content:space-between;gap:15px;font-size:11px;align-items:center}.badge{color:#246750;background:#e7f3eb;padding:6px 9px;border-radius:4px}.badge.Standard{background:#e9eff9;color:#3b6191}.badge.Challenge{background:#faf0dc;color:#8a6420}.marks{color:#74827e}.question-sheet h2{font-size:24px;line-height:1.3;margin:22px 0 14px}.prompt{font-size:15px;line-height:1.8;white-space:pre-line}.answer-label{display:block;font-size:12px;font-weight:bold;margin:25px 0 10px}.answer-row{display:flex;align-items:center;gap:12px}.answer-row input{width:100%;min-width:0;border:1px solid #bdcbc6;border-radius:4px;padding:13px;background:#fafcfb}.unit{font-size:14px;white-space:nowrap}.answer-help{font-size:11px;color:#76837f;line-height:1.5}.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:22px}.primary,.secondary{border-radius:4px;padding:12px 18px;font-size:13px;font-weight:600}.primary{background:var(--green);color:#fff;border:1px solid var(--green)}.primary:hover{background:#105340}.secondary{background:white;border:1px solid #cdd7d3;color:#415d51}.feedback{margin-top:20px;padding:14px;font-size:13px;line-height:1.6;border-left:3px solid #b58325;background:#fcf5e7}.feedback.correct{background:#edf7f0;border-color:var(--green)}.solution{margin-top:24px;border-top:1px solid var(--line);padding-top:20px;line-height:1.7;font-size:14px}.solution h3{font-size:14px;margin:0 0 10px}.solution ol{padding-left:21px}.solution li{margin-bottom:8px}.question-bottom{display:flex;justify-content:space-between;align-items:center;border-top:1px solid var(--line);margin-top:26px;padding-top:18px;gap:12px}.question-bottom small{color:#788780;font-size:11px}.question-bottom button:disabled{opacity:.4;cursor:default}.empty{padding:40px 20px;text-align:center;line-height:1.8;color:#65786e}.choices{display:grid;gap:9px;margin-top:20px}.choice{display:flex;gap:10px;align-items:start;padding:12px;border:1px solid var(--line);border-radius:4px;font-size:14px;line-height:1.5}.choice:has(input:checked){border-color:var(--green);background:#f0f7f3}textarea{resize:vertical;width:100%;min-height:120px;padding:12px;border:1px solid #bdcbc6;border-radius:4px}.diagram{width:100%;height:130px;display:block;background:#f6f9f8;margin-top:18px;border-radius:4px}footer{border-top:1px solid var(--line);margin-top:30px;padding-top:18px;display:flex;justify-content:space-between;gap:20px;font-size:10px;line-height:1.6;color:#7b8983}footer a{color:#526d60}button:disabled{cursor:default;opacity:.65}@media(min-width:1500px){main{padding:44px 64px}}@media(max-width:1150px){main{padding:28px}.layout{grid-template-columns:220px 1fr}.practice-layout{grid-template-columns:190px minmax(0,1fr);gap:18px}.question-sheet{padding:24px}.controls{gap:16px}h1{font-size:30px}}@media(max-width:850px){header{padding:0 22px;height:72px}.layout{display:block}aside{padding:20px;border-right:0;border-bottom:1px solid var(--line)}aside>h2,aside>.section-label,.aside-note,.topic-group{display:none}#topics{display:flex;overflow-x:auto;gap:8px}.topic-button{width:auto;flex:0 0 auto;max-width:220px;border:1px solid var(--line);padding:10px 12px}.heading{margin-bottom:24px}.practice-layout{grid-template-columns:180px minmax(0,1fr)}}@media(max-width:600px){main{padding:25px 18px}header{padding:0 18px}.brand{font-size:17px;gap:8px}.brand-symbol{width:30px;height:32px;font-size:23px}.course{font-size:9px}.course b{margin-left:5px;padding-left:5px}h1{font-size:26px}.progress-summary{padding-left:14px;font-size:10px}.progress-summary strong{font-size:27px}.controls{gap:18px}.controls>div:first-child,.controls input[type=search]{width:100%}.segmented button{padding:9px 10px;font-size:11px}.practice-layout{display:flex;flex-direction:column;gap:18px}#question-list{width:100%;flex-direction:row;max-height:none;padding-bottom:6px}.question-link{flex:0 0 190px}#question{width:100%}.question-sheet{padding:22px 18px}.question-sheet h2{font-size:22px}.workspace-heading h2{font-size:17px}footer{flex-direction:column;gap:7px}.heading{gap:10px}.progress-summary span{max-width:70px}}
.question-preview{display:none}
.practice-layout.browsing{display:block}
.practice-layout.browsing #question-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));max-height:none;overflow:visible;gap:16px}
.browsing .question-link{display:flex;flex-direction:column;gap:14px;padding:22px;height:100%;min-width:0}
.browsing .question-link .mini-meta{align-items:center;width:100%;gap:12px}
.browsing .question-link strong{font-size:18px;margin:0}
.browsing .question-preview{display:block;font-size:13px;line-height:1.7;white-space:pre-line}
.browsing .question-link small{margin-top:auto;line-height:1.6}
.workspace-heading #count{margin-left:auto}
#back-to-questions{margin-bottom:18px}
.katex{font-size:1.08em;white-space:normal}
.katex-display{max-width:100%;overflow-x:auto;overflow-y:hidden;padding:6px 0}
.question-preview,.prompt,.solution,.choice>span{min-width:0;overflow-wrap:anywhere}
.question-preview .katex,.prompt .katex,.solution .katex{display:inline-block;max-width:100%;overflow-x:auto;overflow-y:hidden;vertical-align:middle;padding:2px 0}
.unit{max-width:45%;white-space:normal}
.unit .katex{max-width:100%;overflow-x:auto;overflow-y:hidden}
aside{align-self:start;position:sticky;top:0;max-height:100vh;overflow-y:auto}
@media(min-width:701px) and (max-width:850px){
  .layout{display:grid;grid-template-columns:210px minmax(0,1fr)}
  aside{border-right:1px solid var(--line);padding:24px 12px}
  .heading{flex-wrap:wrap}
  .progress-summary{border-left:0;padding-left:0}
  .practice-layout{grid-template-columns:minmax(0,1fr)}
}
@media(max-width:850px){
  aside>h2,aside>.section-label,.topic-group{display:block}
  #topics{display:block;overflow:visible}
  .topic-button{width:100%;max-width:none;border:0}
  .practice-layout.browsing #question-list{grid-template-columns:minmax(0,1fr)}
}
@media(max-width:700px){
  aside{position:static;max-height:none;overflow:visible}
}
[hidden]{display:none!important}
.static-host #account-screen{display:none!important}
.view-tabs{flex-wrap:wrap}
.landing-screen{padding:42px 18px 60px;max-width:1200px;margin:0 auto}
.landing-hero{position:relative;overflow:hidden;background:radial-gradient(circle at top left,#f8fff7 0%,#edf8f4 26%,#fffaf1 62%,#fff5e7 100%);border:1px solid var(--line);border-radius:28px;padding:30px 28px 24px;box-shadow:0 20px 50px rgba(19,57,49,.08),0 0 0 1px rgba(255,255,255,.5) inset;animation:heroPulse 12s ease-in-out infinite alternate}
.landing-hero:before,.landing-hero:after{content:"";position:absolute;border-radius:50%;filter:blur(8px);animation:drift 9s ease-in-out infinite alternate}
.landing-hero:before{inset:auto -100px -120px auto;width:300px;height:300px;background:radial-gradient(circle,#f7d067 0%,rgba(247,208,103,.85) 24%,rgba(247,208,103,0) 68%);opacity:1;box-shadow:0 0 40px rgba(255,191,69,.38)}
.landing-hero:after{inset:-70px auto auto -90px;width:260px;height:260px;background:radial-gradient(circle,#afe1c9 0%,rgba(175,225,201,.72) 24%,rgba(175,225,201,0) 72%);box-shadow:0 0 36px rgba(122,191,157,.22)}
.landing-hero .spark{position:absolute;display:block;width:8px;height:8px;border-radius:50%;background:#f8d777;box-shadow:0 0 10px rgba(248,215,119,.7),0 0 26px rgba(248,215,119,.45);animation:twinkle 3s ease-in-out infinite}
.landing-hero .spark:nth-child(1){top:18%;right:18%;animation-delay:0s}
.landing-hero .spark:nth-child(2){top:30%;right:28%;width:6px;height:6px;animation-delay:.8s}
.landing-hero .spark:nth-child(3){top:58%;right:14%;width:10px;height:10px;animation-delay:1.2s}
.landing-hero .spark:nth-child(4){top:24%;right:42%;width:7px;height:7px;animation-delay:2s}
.landing-hero .spark:nth-child(5){top:42%;right:22%;width:5px;height:5px;animation-delay:1.6s}
.landing-hero .spark:nth-child(6){top:16%;right:52%;width:9px;height:9px;animation-delay:2.4s}
.landing-hero .spark:nth-child(7){top:70%;right:36%;width:6px;height:6px;animation-delay:1.1s}
.landing-hero .spark:nth-child(8){top:52%;right:58%;width:8px;height:8px;animation-delay:2.8s}
.hero-badge{display:inline-flex;align-items:center;padding:7px 12px;border-radius:999px;background:rgba(25,107,89,.08);border:1px solid rgba(25,107,89,.18);color:var(--green);font-size:11px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;position:relative;z-index:1}
.landing-hero h1{position:relative;z-index:1;margin:18px 0 12px;font-size:clamp(2.3rem,4vw,4rem);line-height:1.05;letter-spacing:-.05em;text-shadow:0 8px 18px rgba(18,61,54,.08);background:linear-gradient(120deg,#1d473f 0%,#1d7a5e 28%,#e1b24d 52%,#1f5b4f 76%,#1d473f 100%);-webkit-background-clip:text;background-clip:text;color:transparent;position:relative;display:inline-block}
.landing-hero h1:after{content:"Physics Forge";position:absolute;inset:0;color:transparent;background:linear-gradient(120deg,rgba(255,255,255,.9),rgba(255,255,255,0));-webkit-background-clip:text;background-clip:text;mix-blend-mode:screen;opacity:.7;transform:translateX(2px);pointer-events:none}
.landing-hero p{position:relative;z-index:1;max-width:760px;margin:0;font-size:1.02rem;line-height:1.75;color:#465d5e}
.landing-actions{position:relative;z-index:1;display:flex;flex-wrap:wrap;gap:12px;margin-top:24px}
.landing-metrics{position:relative;z-index:1;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:28px;max-width:620px}
.landing-metrics div{padding:16px 18px;border:1px solid rgba(21,107,89,.12);border-radius:14px;background:rgba(255,255,255,.59);backdrop-filter:blur(8px)}
.landing-metrics strong{display:block;font-size:1.5rem;line-height:1.1;color:var(--green)}
.landing-metrics span{font-size:.78rem;letter-spacing:.08em;text-transform:uppercase;color:#5a7073}
.landing-showcase{margin-top:26px}
.landing-carousel{overflow:hidden;border-radius:20px}
.landing-track{display:flex;transition:transform .6s cubic-bezier(.22,1,.36,1)}
.landing-slide{min-width:100%}
.landing-card{display:grid;grid-template-columns:auto 1fr;align-items:center;gap:14px 16px;width:100%;padding:22px 20px;border:1px solid var(--line);border-radius:18px;background:linear-gradient(180deg,#ffffff,#f8fbfa);color:inherit;text-align:left;box-shadow:0 18px 30px rgba(18,61,54,.05),0 0 0 1px rgba(255,255,255,.7) inset;transition:transform .2s ease, box-shadow .2s ease, border-color .2s ease, background .2s ease;animation:cardReveal .55s ease both}
.landing-card:hover{transform:translateY(-2px);border-color:#b3cdbf;box-shadow:0 18px 30px rgba(18,61,54,.10),0 0 0 1px rgba(255,255,255,.7) inset;filter:drop-shadow(0 0 12px rgba(131,201,170,.28))}
.landing-card:focus-visible,.carousel-button:focus-visible,.carousel-dot:focus-visible{outline:3px solid #d99b34;outline-offset:3px}
.landing-icon{width:56px;height:56px;border-radius:16px;background:linear-gradient(135deg,#1b6d5d,#1d8f72);color:#fff;display:grid;place-items:center;font-weight:800;font-size:1.2rem;box-shadow:inset 0 -6px 0 rgba(0,0,0,.08),0 0 20px rgba(27,109,93,.25);animation:iconGlow 2.4s ease-in-out infinite alternate}
.landing-card-title{grid-column:2;font-size:1.08rem;font-weight:700;color:var(--green)}
.landing-card-copy{grid-column:2;font-size:.93rem;line-height:1.65;color:#4f6465}
.landing-carousel-controls{display:flex;align-items:center;justify-content:center;gap:18px;margin-top:18px}
.carousel-button{width:42px;height:42px;border:1px solid var(--line);border-radius:50%;background:rgba(255,255,255,.72);color:inherit;display:grid;place-items:center;transition:transform .2s ease, background .2s ease, border-color .2s ease}
.carousel-button:hover{transform:translateY(-1px);border-color:#b7d3c9;background:rgba(245,250,247,.9)}
.carousel-dots{display:flex;align-items:center;gap:8px}
.carousel-dot{width:10px;height:10px;border:0;padding:0;border-radius:50%;background:rgba(21,107,89,.26);transition:transform .2s ease, background .2s ease;position:relative}
.carousel-dot.active{background:var(--green);transform:scale(1.25);box-shadow:0 0 0 4px rgba(21,107,89,.14)}
@keyframes drift{0%{transform:translate3d(0,0,0) scale(1)}50%{transform:translate3d(12px,-10px,0) scale(1.12)}100%{transform:translate3d(-10px,12px,0) scale(1.05)}}
@keyframes twinkle{0%,100%{opacity:.45;transform:scale(.8)}50%{opacity:1;transform:scale(1.4)}}
@keyframes heroPulse{0%{box-shadow:0 20px 50px rgba(19,57,49,.08),0 0 0 1px rgba(255,255,255,.5) inset}100%{box-shadow:0 30px 68px rgba(24,82,71,.15),0 0 0 1px rgba(255,255,255,.65) inset}}
@keyframes cardReveal{0%{opacity:0;transform:translateY(12px) scale(.98)}100%{opacity:1;transform:translateY(0) scale(1)}}
@keyframes iconGlow{0%{transform:scale(1);box-shadow:inset 0 -6px 0 rgba(0,0,0,.08),0 0 0 rgba(27,109,93,0)}100%{transform:scale(1.04);box-shadow:inset 0 -6px 0 rgba(0,0,0,.08),0 0 18px rgba(27,109,93,.22)}}
#challenge-view{max-width:880px;margin:0 auto}.challenge-toggle{display:flex;align-items:center;gap:10px;font-size:14px;white-space:nowrap}
.challenge-progress{border-block:1px solid var(--line);padding:22px 0;margin-bottom:30px}.challenge-progress>div{display:flex;justify-content:space-between;align-items:center;margin-bottom:14px;font-size:13px}.challenge-progress strong{font-size:24px;color:var(--green)}
.challenge-progress progress{appearance:none;display:block;width:100%;height:14px;border:0;border-radius:4px;background:#dde8e2;overflow:hidden}.challenge-progress progress::-webkit-progress-bar{background:#dde8e2}.challenge-progress progress::-webkit-progress-value{background:var(--green)}.challenge-progress progress::-moz-progress-bar{background:var(--green)}
.challenge-question{padding:6px 0 28px}.challenge-question h2{font-size:24px;line-height:1.4;margin:22px 0 14px}.challenge-question .question-top{flex-wrap:wrap}.challenge-question .answer-row{max-width:520px}.challenge-complete{padding:36px 0;min-height:240px}.challenge-complete h2{font-size:28px}
#challenge-error{color:#a23434;line-height:1.6}[data-theme=dark] #challenge-error{color:#ffa4a4}[data-theme=dark] .challenge-progress progress,[data-theme=dark] .challenge-progress progress::-webkit-progress-bar{background:#35473d}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
#challenge-view{max-width:1200px}.challenge-layout{display:grid;grid-template-columns:220px minmax(0,1fr);gap:36px}.challenge-options{border-right:1px solid var(--line);padding-right:22px}.challenge-options h2{font-size:18px;margin:12px 0 20px}.challenge-options p,.challenge-options label{font-size:13px;line-height:1.6}.challenge-options label{display:flex;align-items:flex-start;gap:8px;margin:20px 0 12px}.challenge-options input{margin-top:4px;flex-shrink:0}.challenge-options ul{padding-left:20px;font-size:12px;line-height:1.9;color:#637572}.challenge-main{min-width:0}[data-theme=dark] .challenge-options ul{color:#b5c6bd}
@media(max-width:850px){.challenge-layout{grid-template-columns:minmax(0,1fr);gap:24px}.challenge-options{border-right:0;border-bottom:1px solid var(--line);padding:0 0 16px}.challenge-options ul{display:none}.challenge-options h2{margin:0 0 12px}}
@media(max-width:600px){.view-tabs{gap:4px 16px}.view-tabs button{font-size:12px;padding-inline:0}.challenge-question h2{font-size:21px}}
select{font:inherit;max-width:100%}
header{height:auto;min-height:86px;gap:20px;flex-wrap:wrap;padding-top:16px;padding-bottom:16px}
.header-actions{display:flex;align-items:center;gap:14px;flex-wrap:wrap;font-size:12px}
dialog{width:min(620px,calc(100% - 32px));border:1px solid var(--line);border-radius:6px;padding:0;color:inherit;background:white;box-shadow:0 20px 70px #15251d33}dialog::backdrop{background:#15251d66}.dialog-content{padding:0}#enquiries-form{padding:28px}#enquiries-form .heading{margin-bottom:12px}#enquiries-form h2{margin:0;font-size:24px}#enquiries-form label{display:grid;gap:8px;margin:18px 0;font-size:13px}#enquiries-form input,#enquiries-form select,#enquiries-form textarea{width:100%;border:1px solid #bdcbc6;border-radius:4px;padding:11px;background:white;color:inherit;resize:vertical}#enquiries-form textarea{min-height:130px}#enquiries-error{color:#a23434;font-size:13px;line-height:1.5;min-height:1.5em}.enquiries-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:20px}
.role-view-switch{display:flex;justify-content:flex-end;padding:8px 24px;border-bottom:1px solid var(--line)}
.icon-button{width:38px;height:38px;border:1px solid var(--line);border-radius:4px;background:transparent;color:inherit;font-size:22px}
.account-panel{max-width:440px;margin:50px auto;padding:0 24px}
#skip-login{display:block;width:100%;margin-top:24px}
#teacher-invitation-result{max-width:560px;margin-top:16px;font-size:13px;line-height:1.6}#invitation-code{display:block;width:100%;padding:12px;margin-top:8px;border:1px solid var(--line);border-radius:4px}
#microsoft-signin{width:100%;margin:18px 0 8px}.account-connections{text-align:right;padding:0 40px}.account-connections:has([hidden]){display:none}#global-status:not(:empty){padding:16px 24px;font-size:14px;line-height:1.6}
.account-screen{padding:42px 18px}.account-screen>.section-label,.account-screen>h1{text-align:center}
.account-panel h1{margin-bottom:26px}
#account-tabs{display:flex;gap:20px;border-bottom:1px solid var(--line);margin-bottom:24px}
#account-tabs button,.view-tabs button{background:none;color:inherit;border:0;border-bottom:3px solid transparent;padding:15px 8px;font-size:14px}
#account-tabs button[aria-pressed=true],.view-tabs button[aria-current=page]{border-color:var(--green);color:var(--green);font-weight:700}
#account-form label,#teacher-form label{display:grid;gap:8px;margin:18px 0;font-size:13px}
#account-form input,#account-form select,#teacher-form input{width:100%;border:1px solid #bdcbc6;border-radius:4px;padding:12px;background:white;color:inherit}
#account-submit{width:100%;margin:12px 0}
#account-error{color:#a23434;line-height:1.6;font-size:13px}
.view-tabs{display:flex;gap:24px;padding:0 40px;background:white;border-bottom:1px solid var(--line)}
.gradebook-layout{grid-template-columns:minmax(0,1fr)}
.layout main{align-self:start;margin-top:0}
.notes-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 24px;margin-top:28px}
.notes-index button{text-align:left;border:0;border-bottom:1px solid var(--line);border-radius:0;background:none;padding:20px 0;color:var(--green)}
.notes-toc{display:flex;flex-wrap:wrap;gap:12px 22px;border-block:1px solid var(--line);padding:20px 0}
a{color:var(--green)}
.note-section{border-bottom:1px solid var(--line);padding:26px 0;max-width:900px;scroll-margin-top:20px}
.note-section h2{font-size:22px;margin:0 0 18px}
.note-section p{font-size:15px;line-height:1.85;overflow-wrap:anywhere}
.note-section .katex{max-width:100%;overflow:auto;display:inline-block;vertical-align:middle;padding:3px 0}
.source-note{font-size:12px;line-height:1.7;color:#667773;margin-top:30px}
.notes-heading{margin-bottom:28px}.notes-heading h1{font-size:30px;max-width:700px}
.notes-back{background:none;border:0;padding:0;margin-bottom:24px;color:var(--green);font-size:13px}
.notes-index .note-topic{display:grid;grid-template-columns:32px minmax(0,1fr) 18px;align-items:start;gap:14px;padding:24px 0;color:inherit;font-weight:400}
.note-topic strong{display:block;font-size:17px;line-height:1.4;font-weight:600}.note-topic small{display:block;font-size:12px;line-height:1.7;margin:10px 0;color:#637572}
.note-topic-meta{font-size:11px;color:var(--green)}.note-topic:hover strong{text-decoration:underline;text-underline-offset:4px}
.note-number{font-size:12px;color:var(--green);font-weight:700;line-height:2}
.notes-toc{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px 24px;padding:22px 0;margin-bottom:12px}
.notes-toc a{display:flex;gap:12px;align-items:baseline;font-size:13px;text-decoration:none;line-height:1.5}.notes-toc a:hover{text-decoration:underline}.notes-toc span{font-size:11px;opacity:.75}
.notes-reading{max-width:920px}.note-section{max-width:none;padding:32px 0;scroll-margin-top:24px}
.note-section-heading{display:grid;grid-template-columns:32px minmax(0,1fr);gap:14px;align-items:baseline;margin-bottom:18px}.note-section-heading h2{font-size:21px;margin:0;line-height:1.4}
.note-body{padding-left:46px;max-width:850px}.note-point,.note-equation{font-size:15px;line-height:1.85;overflow-wrap:anywhere;margin:0 0 16px}
.note-point:last-child{margin-bottom:0}.note-equation{border-left:3px solid #539981;background:#eaf2ee;padding:16px 20px;margin:18px 0 22px}
.note-practical-group{margin:24px 0}.note-practical-group h3{font-size:17px;line-height:1.5;margin:0 0 10px}.note-practical-group ol,.note-practical-group ul{padding-left:24px;margin:0}.note-practical-group li{padding-left:4px;margin:0 0 12px;font-size:15px;line-height:1.85;overflow-wrap:anywhere}.note-section .note-practical-source{font-size:12px;line-height:1.7;opacity:.8;margin:0 0 20px}
.note-example .note-number{color:#996812}.note-example .note-body{border-left:3px solid #d2a249;padding:4px 0 4px 20px;margin-left:14px}
.note-figure{margin:28px 0 6px;padding:20px 0 0;border-top:1px solid var(--line)}.note-figure h3{font-size:14px;margin:0 0 14px}.note-figure canvas{width:100%;max-width:680px;height:auto;aspect-ratio:15/7;display:block}.note-figure figcaption{font-size:12px;color:#637572;line-height:1.7;max-width:640px;margin-top:12px}.note-controls{max-width:680px;padding:14px 16px;margin:0 0 16px;background:#edf4f0;border:1px solid var(--line);border-radius:5px}.note-control-row{display:flex;align-items:center;gap:18px}.note-control-row+ .note-control-row{margin-top:14px}.note-control-row label{display:grid;grid-template-columns:auto auto;gap:4px 10px;flex:1;font-size:12px}.note-control-row input{grid-column:1 / -1;width:100%;accent-color:var(--green)}.note-control-row output{color:var(--green);font-weight:700;text-align:right}.note-control-actions>span{font-size:12px}.note-control-actions .segmented{margin-left:auto}.note-control-actions strong{font-size:12px;color:var(--green);white-space:nowrap}
.notes-source{max-width:920px;margin-top:24px;font-size:12px;line-height:1.7;color:#637572}.notes-source summary{cursor:pointer}.notes-source p{margin:12px 0}
.note-section .note-reference{font-size:11px;color:#637572;margin:0 0 18px;line-height:1.6}[data-theme=dark] .note-section .note-reference{color:#b5c6bd}
[data-theme=dark] .note-equation{background:#243b30;border-color:#76d6b1}[data-theme=dark] .note-topic small,[data-theme=dark] .note-figure figcaption,[data-theme=dark] .notes-source{color:#b5c6bd}[data-theme=dark] .note-example .note-number{color:#f1c66f}[data-theme=dark] .note-controls{background:#24352c}
@media(max-width:600px){.notes-heading h1{font-size:26px}.notes-toc{grid-template-columns:minmax(0,1fr)}.note-body{padding-left:0}.note-section-heading{gap:8px;grid-template-columns:26px minmax(0,1fr)}.note-section-heading h2{font-size:19px}.note-equation{padding:14px}.note-example .note-body{margin-left:0}.note-point,.note-equation{font-size:14px}.note-figure figcaption{min-width:0}.notes-index .note-topic{gap:10px}.note-control-row{display:grid;grid-template-columns:minmax(0,1fr);gap:12px}.note-control-actions .segmented{margin-left:0}.note-control-actions strong{justify-self:start}}
.table-scroll{overflow-x:auto;max-width:100%;margin:24px 0}
table{border-collapse:collapse;width:100%;font-size:13px;text-align:left}
th{font-size:11px;color:#637572;background:#edf2f0;white-space:nowrap}
td,th{padding:15px 14px;border-bottom:1px solid var(--line);vertical-align:top;line-height:1.5}
td small{display:block;color:#667773;margin-top:5px}
.student-link{border:0;background:none;padding:0;color:var(--green);text-decoration:underline;text-align:left;font:inherit;font-weight:600}
.response-cell{min-width:160px;max-width:360px;white-space:pre-wrap;overflow-wrap:anywhere}
.teacher-admin{margin-top:36px;padding-top:24px;border-top:1px solid var(--line)}
.teacher-admin summary{cursor:pointer;font-size:14px}
#teacher-form{max-width:440px}
#hints{font-size:14px;line-height:1.8}
#hints h3{font-size:14px;margin-top:24px}
.question-bottom>a{font-size:12px;line-height:1.5}
.question-bottom>div{flex-shrink:0}
:root[data-theme=dark]{color-scheme:dark;background:#191c1b;color:#e1e9e5;--green:#76d6b1;--line:#3e4843}
[data-theme=dark] header,[data-theme=dark] aside,[data-theme=dark] .view-tabs,[data-theme=dark] .question-sheet,[data-theme=dark] .question-link{background:#222724}
[data-theme=dark] .topic-button,[data-theme=dark] .secondary,[data-theme=dark] .segmented button{color:#c7d6ce}
[data-theme=dark] .topic-button:hover,[data-theme=dark] .topic-button.active,[data-theme=dark] .question-link.active,[data-theme=dark] .choice:has(input:checked){background:#263d32;color:#aff0d1}
[data-theme=dark] .primary,[data-theme=dark] .segmented button[aria-pressed=true]{background:#76d6b1;color:#13261d;border-color:#76d6b1}
[data-theme=dark] .primary:hover{background:#a1e8c9}
[data-theme=dark] input,[data-theme=dark] textarea,[data-theme=dark] select,[data-theme=dark] .secondary,[data-theme=dark] .segmented{background:#252c28!important;color:#e1e9e5!important;border-color:#526459!important}
[data-theme=dark] dialog{background:#222724;box-shadow:0 20px 70px #0008}
[data-theme=dark] .landing-hero{background:radial-gradient(circle at top left,#1c2b2f 0%,#101b1d 38%,#17191e 100%);border-color:#3d4a46;box-shadow:0 20px 50px rgba(0,0,0,.32),0 0 0 1px rgba(255,255,255,.04) inset}
[data-theme=dark] .landing-hero:before{background:radial-gradient(circle,#ffd37f 0%,rgba(255,211,127,.82) 18%,rgba(255,211,127,0) 64%);box-shadow:0 0 44px rgba(255,191,69,.15)}
[data-theme=dark] .landing-hero:after{background:radial-gradient(circle,#94e4c3 0%,rgba(148,228,195,.7) 16%,rgba(148,228,195,0) 62%);box-shadow:0 0 30px rgba(148,228,195,.12)}
[data-theme=dark] .landing-hero h1{background:linear-gradient(120deg,#d5eaf0 0%,#93f0d0 25%,#f7d77e 48%,#a7efe0 70%,#d9ebee 100%);-webkit-background-clip:text;background-clip:text;color:transparent}
[data-theme=dark] .landing-hero p,[data-theme=dark] .landing-card-copy,[data-theme=dark] .landing-metrics span{color:#c0d3cd}
[data-theme=dark] .hero-badge{background:rgba(118,214,177,.08);border-color:rgba(118,214,177,.2)}
[data-theme=dark] .landing-metrics div{background:rgba(18,27,27,.72);border-color:rgba(118,214,177,.2)}
[data-theme=dark] .landing-card{background:linear-gradient(180deg,#1f2b29,#151b1c);border-color:#3d4a46;box-shadow:0 18px 30px rgba(0,0,0,.22),0 0 0 1px rgba(255,255,255,.04) inset}
[data-theme=dark] .landing-card:hover{border-color:#66b89a;box-shadow:0 20px 30px rgba(0,0,0,.28),0 0 0 1px rgba(255,255,255,.05) inset;filter:drop-shadow(0 0 12px rgba(103,201,168,.18))}
[data-theme=dark] .landing-card .landing-icon{background:linear-gradient(135deg,#31796d,#45a882);box-shadow:inset 0 -6px 0 rgba(0,0,0,.12),0 0 18px rgba(72,194,156,.18)}
[data-theme=dark] .carousel-button{background:rgba(19,28,28,.82);border-color:#40564d;color:#e1e9e5}
[data-theme=dark] .carousel-dot{background:rgba(118,214,177,.35)}
[data-theme=dark] .carousel-dot.active{background:#76d6b1;box-shadow:0 0 0 4px rgba(118,214,177,.16)}
[data-theme=dark] .answer-help,[data-theme=dark] .section-label,[data-theme=dark] .course,[data-theme=dark] .source-note,[data-theme=dark] .controls label,[data-theme=dark] .controls legend,[data-theme=dark] .progress-summary,[data-theme=dark] .question-link small,[data-theme=dark] .mini-meta,[data-theme=dark] td small,[data-theme=dark] footer,[data-theme=dark] #count{color:#aebfb5}
[data-theme=dark] .badge{background:#244736;color:#a9e9c5}
[data-theme=dark] .badge.Standard{background:#283c56;color:#bfd3f4}
[data-theme=dark] .badge.Challenge{background:#4e4024;color:#f4d593}
[data-theme=dark] .feedback{background:#3c3423;color:#f5dfb5}
[data-theme=dark] .feedback.correct{background:#263d32;color:#b4eed2}
[data-theme=dark] th{background:#29332d;color:#c7d6ce}
[data-theme=dark] #account-error{color:#ffa4a4}
@media(max-width:700px){.view-tabs{padding:0 18px;gap:20px}.header-actions{gap:10px}.heading{flex-wrap:wrap}.notes-index{grid-template-columns:minmax(0,1fr)}.question-bottom{flex-wrap:wrap}.account-panel{margin-top:30px}h1{overflow-wrap:anywhere}}
@media(max-width:600px){.practice-layout.browsing #question-list{grid-template-columns:minmax(0,1fr)}.workspace-heading{flex-wrap:wrap}.workspace-heading h2{flex-basis:100%}.workspace-heading #count{margin-left:0;margin-right:auto}}