:root{
  --bg:#f6f7fb;--surface:#fff;--ink:#14161f;--muted:#667085;--line:#e4e7ee;--brand:#326ce5;--brand-ink:#fff;
  --ok:#12a150;--warn:#f59e0b;--bad:#e5484d;--heat0:#eceff5;--heat1:#c7d8fb;--heat2:#8fb0f5;--heat3:#4e82ea;--heat4:#1f4fb8;
  --shadow:0 1px 2px rgba(16,24,40,.06),0 4px 16px rgba(16,24,40,.05);
}
@media (prefers-color-scheme:dark){:root{
  --bg:#0e1118;--surface:#171b26;--ink:#eef1f8;--muted:#9aa3b5;--line:#272d3d;--brand:#5b8cff;--brand-ink:#0b1020;
  --heat0:#232a3a;--heat1:#27407a;--heat2:#2f58b0;--heat3:#4679e6;--heat4:#8db0ff;--shadow:none;}}
*{box-sizing:border-box}
html,body{margin:0}
body{font:15px/1.5 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;background:var(--bg);color:var(--ink)}
a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}
h1,h2,h3{line-height:1.2;margin:0 0 .5em}h1{font-size:1.6rem}h2{font-size:1.15rem}h3{font-size:1rem}
button,input,select,textarea{font:inherit;color:inherit}
.btn{background:var(--brand);color:var(--brand-ink);border:0;border-radius:8px;padding:.5em .95em;cursor:pointer;font-weight:600}
.btn:hover{filter:brightness(1.08)}.btn:disabled{opacity:.5;cursor:default}
.btn.ghost{background:transparent;color:var(--ink);border:1px solid var(--line)}
.btn.sm{padding:.25em .6em;font-size:.85rem}
.btn.danger{background:var(--bad);color:#fff}
input[type=text],input[type=password],input[type=number],input[type=date],input[type=time],input[type=search],select{
  background:var(--surface);border:1px solid var(--line);border-radius:8px;padding:.5em .7em;width:100%}
label{display:block;font-weight:600;font-size:.85rem;margin:.8em 0 .25em}
.muted{color:var(--muted)}.small{font-size:.85rem}
.card{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:1.1rem 1.2rem;box-shadow:var(--shadow)}
.grid{display:grid;gap:1rem}
.g2{grid-template-columns:repeat(auto-fit,minmax(300px,1fr))}
.g3{grid-template-columns:repeat(auto-fit,minmax(200px,1fr))}
.row{display:flex;gap:.6rem;align-items:center;flex-wrap:wrap}.space{justify-content:space-between}
.hide{display:none!important}

/* shell */
.nav{position:sticky;top:0;z-index:10;background:var(--surface);border-bottom:1px solid var(--line)}
.nav-in{max-width:1100px;margin:0 auto;padding:.6rem 1rem;display:flex;gap:.3rem;align-items:center;flex-wrap:wrap}
.brand{font-weight:800;margin-right:.8rem;color:var(--ink)}
.nav a.tab{padding:.4em .8em;border-radius:8px;color:var(--muted);font-weight:600}
.nav a.tab:hover{background:var(--bg);text-decoration:none}
.nav a.tab.on{background:var(--bg);color:var(--ink)}
.nav .sp{flex:1}
main{max-width:1100px;margin:0 auto;padding:1.2rem 1rem 4rem}

/* auth */
.auth{max-width:380px;margin:8vh auto;padding:0 1rem}
.auth h1{font-size:1.9rem}
.err{color:var(--bad);font-size:.9rem;min-height:1.3em;margin-top:.5em}

/* nudge */
.nudge{display:flex;gap:.8rem;align-items:center;justify-content:space-between;border-radius:14px;padding:.9rem 1.1rem;margin-bottom:1rem;border:1px solid var(--line);background:var(--surface)}
.nudge.warn{border-color:var(--warn);background:color-mix(in srgb,var(--warn) 12%,var(--surface))}
.nudge.ok{border-color:var(--ok);background:color-mix(in srgb,var(--ok) 10%,var(--surface))}
.nudge.bad{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 10%,var(--surface))}

/* stats */
.stat .big{font-size:2rem;font-weight:800;line-height:1.1}
.stat .lbl{color:var(--muted);font-size:.85rem}
.bar{height:9px;border-radius:99px;background:var(--heat0);overflow:hidden}
.bar>i{display:block;height:100%;border-radius:99px;background:var(--brand)}
.dom{margin:.7rem 0}.dom .top{display:flex;justify-content:space-between;font-size:.88rem;margin-bottom:.25rem}
.chip{display:inline-block;font-size:.72rem;font-weight:700;padding:.1em .55em;border-radius:99px;background:var(--bg);border:1px solid var(--line);color:var(--muted)}
.chip.lab{color:#0a7d4b}.chip.mock{color:#b42318}

/* heatmap */
.heat{display:grid;grid-auto-flow:column;grid-template-rows:repeat(7,13px);grid-auto-columns:13px;gap:3px;overflow-x:auto;padding-bottom:4px}
.heat i{border-radius:3px;background:var(--heat0)}
.heat i[data-l="1"]{background:var(--heat1)}.heat i[data-l="2"]{background:var(--heat2)}
.heat i[data-l="3"]{background:var(--heat3)}.heat i[data-l="4"]{background:var(--heat4)}

/* curriculum */
details.sec{background:var(--surface);border:1px solid var(--line);border-radius:12px;margin-bottom:.6rem}
details.sec>summary{padding:.8rem 1rem;cursor:pointer;display:flex;gap:.8rem;align-items:center;font-weight:700;list-style:none}
details.sec>summary::-webkit-details-marker{display:none}
details.sec>summary .bar{width:110px;margin-left:auto}
.item{display:flex;gap:.7rem;align-items:center;padding:.45rem 1rem;border-top:1px solid var(--line)}
.item input{width:18px;height:18px;accent-color:var(--brand);flex:none}
.item .t{flex:1;min-width:0}.item.done .t a{color:var(--muted);text-decoration:line-through}
.dot{width:9px;height:9px;border-radius:50%;flex:none}
.filters{display:flex;gap:.5rem;flex-wrap:wrap;margin-bottom:1rem}.filters>*{width:auto}

/* calendar */
.cal{display:grid;grid-template-columns:repeat(7,1fr);gap:4px}
.cal .dow{font-size:.75rem;color:var(--muted);text-align:center;font-weight:700;padding:.2rem}
.cal button.day{aspect-ratio:1/0.9;min-height:62px;background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:.3rem .4rem;text-align:left;cursor:pointer;display:flex;flex-direction:column;justify-content:space-between;position:relative}
.cal button.day:hover{border-color:var(--brand)}
.cal button.day.out{opacity:.35}
.cal button.day.today{outline:2px solid var(--brand)}
.cal button.day.sel{background:color-mix(in srgb,var(--brand) 14%,var(--surface))}
.cal button.day[data-l="1"]{background:var(--heat1)}.cal button.day[data-l="2"]{background:var(--heat2)}
.cal button.day[data-l="3"]{background:var(--heat3);color:#fff}.cal button.day[data-l="4"]{background:var(--heat4);color:#fff}
.cal .n{font-size:.8rem;font-weight:700}
.cal .m{font-size:.68rem;opacity:.9}
.cal .pl{position:absolute;right:5px;top:5px;font-size:.65rem;background:var(--warn);color:#000;border-radius:99px;padding:0 .4em;font-weight:700}
.cal .exam{position:absolute;right:5px;bottom:4px;font-size:.9rem}
.side .li{display:flex;gap:.5rem;align-items:center;padding:.35rem 0;border-top:1px solid var(--line)}
.side .li .t{flex:1;min-width:0;font-size:.9rem}

/* tables */
table{width:100%;border-collapse:collapse}th,td{padding:.55rem .5rem;text-align:left;border-bottom:1px solid var(--line)}
th{font-size:.78rem;text-transform:uppercase;letter-spacing:.04em;color:var(--muted);cursor:pointer;user-select:none}
tr.me td{background:color-mix(in srgb,var(--brand) 9%,transparent);font-weight:600}
.avatar{width:30px;height:30px;border-radius:50%;display:inline-grid;place-items:center;background:var(--brand);color:var(--brand-ink);font-weight:800;font-size:.85rem;margin-right:.5rem;vertical-align:middle}

/* lesson */
.lesson{max-width:820px}
.lesson .md img{max-width:100%;height:auto;border:1px solid var(--line);border-radius:6px}
.lesson .md pre{background:#0f1420;color:#e6edf7;padding:.8rem 1rem;border-radius:8px;overflow:auto;font-size:1em;line-height:1.55}
.lesson .md code{background:var(--bg);padding:.1em .35em;border-radius:4px;font-size:1em}
.lesson .md pre code{background:none;padding:0}
.lesson .md table{display:block;overflow:auto}
.lesson .md blockquote{border-left:4px solid var(--line);margin-left:0;padding-left:1rem;color:var(--muted)}
.sticky-bar{position:sticky;bottom:0;background:var(--surface);border-top:1px solid var(--line);padding:.7rem 0;margin-top:2rem;display:flex;gap:.6rem;align-items:center;flex-wrap:wrap}

#toast{position:fixed;left:50%;bottom:20px;transform:translateX(-50%) translateY(80px);background:var(--ink);color:var(--bg);padding:.6rem 1rem;border-radius:10px;opacity:0;transition:.25s;z-index:50;max-width:90vw}
#toast.on{transform:translateX(-50%);opacity:1}
@media (max-width:640px){.cal button.day{min-height:52px;padding:.2rem}.cal .m{display:none}details.sec>summary .bar{width:60px}}

.split{grid-template-columns:minmax(0,2fr) minmax(260px,1fr);align-items:start}
@media (max-width:800px){.split{grid-template-columns:minmax(0,1fr)}}
.cal>*{min-width:0}
.cal button.day{width:100%;min-width:0;overflow:hidden}
@media (max-width:640px){.cal{gap:3px}.cal .pl{right:2px;top:2px;padding:0 .3em}.cal .n{font-size:.75rem}}

.with-side{display:grid;grid-template-columns:minmax(0,1fr) 330px;gap:1.5rem;align-items:start}
.with-side .lesson{max-width:none}
.side-tabs{position:sticky;top:64px;max-height:calc(100vh - 80px);overflow:auto;padding:.8rem}
.side-tabs .tabs{display:flex;gap:.25rem;margin-bottom:.8rem;border-bottom:1px solid var(--line);padding-bottom:.5rem}
.side-tabs .tabs button{flex:1;background:none;border:0;border-radius:8px;padding:.35rem .2rem;cursor:pointer;font-weight:600;font-size:.82rem;color:var(--muted)}
.side-tabs .tabs button.on{background:var(--bg);color:var(--ink)}
.side-tabs h3{font-size:.78rem;text-transform:uppercase;letter-spacing:.04em;color:var(--muted);margin:1rem 0 .4rem}
a.vid{display:flex;flex-direction:column;gap:.15rem;align-items:flex-start;padding:.55rem .65rem;border:1px solid var(--line);border-radius:10px;margin-bottom:.45rem;color:var(--ink);background:var(--surface)}
a.vid:hover{border-color:var(--brand);text-decoration:none}
a.vid b{font-size:.88rem;line-height:1.3}
@media (max-width:1000px){.with-side{grid-template-columns:minmax(0,1fr)}.side-tabs{position:static;max-height:none}}

.vdot{width:10px;height:10px;border-radius:50%;flex:none;border:2px solid var(--line);background:transparent;display:inline-block}
.vdot.on{background:#16a34a;border-color:#16a34a}
.guide{border:1px solid var(--line);border-left:4px solid var(--brand);border-radius:12px;background:color-mix(in srgb,var(--brand) 5%,var(--surface));padding:1rem 1.2rem;margin:1rem 0}
.guide-h{font-weight:800;margin-bottom:.4rem}
.guide .md h3{margin:1.1rem 0 .3rem;font-size:1rem}
.guide .md h4{margin:.9rem 0 .25rem;font-size:.92rem;color:var(--accent,#7aa2ff)}
.guide .md pre{overflow-x:auto;font-size:1em;line-height:1.55}
.guide .md table{font-size:.88rem}

.clock{font:700 3rem/1.1 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;text-align:center;letter-spacing:.02em;font-variant-numeric:tabular-nums;margin:.4rem 0}
.timer-pill{border:1px solid var(--line);background:var(--surface);color:var(--ink);border-radius:99px;padding:.2em .7em;font:600 .8rem ui-monospace,Menlo,Consolas,monospace;cursor:pointer}
.timer-pill.on{border-color:var(--ok);color:var(--ok)}
.timer-pill.paused{border-color:var(--warn);color:var(--warn)}
.timer-hero{max-width:560px;margin:0 auto}.timer-hero .clock{font-size:3.6rem}
#pre .btn.on{background:var(--brand);color:var(--brand-ink);border-color:transparent}
.nudge.behind{background:#fdecec;border:1px solid var(--bad);color:#7a1d20;margin:.6rem 0}
@media (prefers-color-scheme:dark){.nudge.behind{background:#3a1618;color:#ffb4b6}}
.pl.late{background:var(--bad)!important;color:#fff!important}
.embed{margin:2rem 0 1rem}.embed .ratio{position:relative;aspect-ratio:16/9;border-radius:12px;overflow:hidden;background:#000;border:1px solid var(--line)}.embed iframe{position:absolute;inset:0;width:100%;height:100%;border:0}

/* ---- intro ---- */
body:has(.intro){background:#050a1c}
.intro{position:relative;color:#e8eefc;font-family:"Bricolage Grotesque",Inter,system-ui,sans-serif}
.intro-track{height:700vh}
.intro-stage{position:fixed;inset:0;overflow:hidden}
.intro-stage canvas{position:absolute;inset:0;width:100%;height:100%;display:block}
.intro-top{position:fixed;z-index:5;top:0;left:0;right:0;display:flex;justify-content:space-between;align-items:center;padding:1rem clamp(1rem,4vw,2.4rem)}
.intro-brand{font-weight:800;letter-spacing:-.01em}
.intro-links{display:flex;gap:.5rem}
.il{font:600 .9rem Inter,system-ui,sans-serif;color:#e8eefc;background:transparent;border:1px solid rgba(232,238,252,.25);border-radius:99px;padding:.45rem 1rem;cursor:pointer;transition:background .15s,border-color .15s}
.il:hover{background:rgba(232,238,252,.1)}.il.solid{background:#326ce5;border-color:#326ce5}.il.solid:hover{background:#4a80f0}
.il:focus-visible,.intro .btn:focus-visible{outline:3px solid #ffb454;outline-offset:2px}
.intro-copy{position:absolute;left:clamp(1.2rem,6vw,5rem);top:50%;width:min(32vw,27rem);transform:translateY(-50%);pointer-events:none}
.cap{position:absolute;left:0;right:0;top:50%;opacity:0;margin-top:-5rem}
.cap h2{font-size:clamp(2.1rem,4.4vw,3.8rem);line-height:1.02;font-weight:800;letter-spacing:-.025em;margin:0 0 1rem;color:#fff}
.cap p{font:400 clamp(1rem,1.25vw,1.15rem)/1.55 Inter,system-ui,sans-serif;color:rgba(232,238,252,.78);margin:0;max-width:30ch}
.cta{display:flex;gap:.7rem;flex-wrap:wrap;margin-top:1.5rem}
.intro .btn.big{font-size:1rem;padding:.8rem 1.3rem;border-radius:12px}
.intro .btn.ghost{color:#e8eefc;border-color:rgba(232,238,252,.3);background:transparent}
.intro-rail{position:absolute;right:clamp(.8rem,2vw,1.6rem);top:50%;transform:translateY(-50%);list-style:none;margin:0;padding:0;display:grid;gap:.7rem}
.intro-rail li{width:7px;height:7px;border-radius:50%;background:rgba(232,238,252,.25);transition:background .25s,transform .25s}
.intro-rail li.on{background:#7aa7ff;transform:scale(1.35)}
.intro-hint{position:absolute;left:50%;bottom:1.6rem;transform:translateX(-50%);font:500 .85rem Inter,system-ui,sans-serif;color:rgba(232,238,252,.7);display:grid;justify-items:center;gap:.5rem}
.intro-hint span{width:1px;height:34px;background:linear-gradient(#7aa7ff,transparent);animation:hintDrop 1.6s ease-in-out infinite}
@keyframes hintDrop{0%{transform:scaleY(0);transform-origin:top}50%{transform:scaleY(1);transform-origin:top}51%{transform-origin:bottom}100%{transform:scaleY(0);transform-origin:bottom}}
@media (max-width:880px){
  .intro-copy{left:1.2rem;right:1.2rem;width:auto;top:auto;bottom:2.2rem;transform:none;height:13.5rem}
  .cap{top:auto;bottom:0;margin-top:0}
  .cap h2{font-size:2rem}.cap p{max-width:none}
  .intro-hint{display:none}
}
@media (prefers-reduced-motion:reduce){.intro-hint span{animation:none}}

/* ---- logo + wordmark ---- */
.logo .le{stroke:#a9c6ff}.logo .le5{stroke:#ffb454}.logo .le6{opacity:.3}
.logo{display:block;filter:drop-shadow(0 6px 18px rgba(50,108,229,.45))}
.logo.draw .le{stroke-dasharray:1;stroke-dashoffset:1;animation:logoDraw .7s cubic-bezier(.3,.7,.2,1) forwards;animation-delay:calc(var(--i,0)*70ms)}
.logo.draw .le0{--i:0}.logo.draw .le1{--i:1}.logo.draw .le2{--i:2}.logo.draw .le3{--i:3}.logo.draw .le4{--i:4}.logo.draw .le5{--i:5}.logo.draw .le6{--i:6}
.logo.draw .lc{stroke-dasharray:1;stroke-dashoffset:1;animation:logoDraw .5s cubic-bezier(.3,.7,.2,1) .55s forwards}
.logo.draw polygon{animation:logoPop .6s cubic-bezier(.2,.9,.3,1.3) both;transform-origin:50px 52px}
@keyframes logoDraw{to{stroke-dashoffset:0}}
@keyframes logoPop{from{transform:scale(.4);opacity:0}to{transform:scale(1);opacity:1}}
.wm{font-family:"Bricolage Grotesque",Inter,system-ui,sans-serif;font-weight:700;letter-spacing:-.02em;display:inline-flex;align-items:center;gap:.5rem}
.wm b{font-weight:800}
.nav .brand{display:inline-flex;align-items:center;gap:.5rem;font-family:"Bricolage Grotesque",Inter,system-ui,sans-serif;font-weight:700;letter-spacing:-.02em;font-size:1.08rem}
.nav .brand .logo{width:30px;height:auto;filter:none}
.nav .brand b{font-weight:800}
.hero-logo{width:clamp(56px,6vw,84px);height:auto;margin-bottom:1rem}
.wm-big{font-size:clamp(2.4rem,4.4vw,4.2rem);line-height:.98;font-weight:700;letter-spacing:-.035em;margin:0 0 1.1rem;color:#fff}
.wm-big span{display:block;font-weight:800;font-size:1.28em;letter-spacing:-.045em;background:linear-gradient(100deg,#fff 20%,#9dc0ff);-webkit-background-clip:text;background-clip:text;color:transparent}
.cap.hero{margin-top:-15rem;width:min(42vw,36rem)}.cap.hero .tag{font:400 clamp(1rem,1.3vw,1.15rem)/1.55 Inter,system-ui,sans-serif;color:rgba(232,238,252,.82);margin:0;max-width:42ch}
.auth .authlogo{width:64px;height:auto;margin:0 0 .8rem}
.auth h1{font-family:"Bricolage Grotesque",Inter,system-ui,sans-serif;letter-spacing:-.03em;font-weight:800}
@media (max-width:880px){.intro-copy{height:21rem}.cap.hero{margin-top:0}.hero-logo{width:52px;margin-bottom:.6rem}.wm-big{font-size:2.3rem;margin-bottom:.6rem}.wm-big span{font-size:1.2em}.cap.hero .tag{font-size:.95rem;max-width:none}.cap.hero .cta{margin-top:1rem}}

/* ---- motion ---- */
::view-transition-old(root){animation:vtOut .22s cubic-bezier(.4,0,1,1) both}
::view-transition-new(root){animation:vtIn .12s cubic-bezier(.16,1,.3,1) both}
@keyframes vtOut{to{opacity:0;transform:translateY(-6px) scale(.995)}}
@keyframes vtIn{from{opacity:0;transform:translateY(14px) scale(.995)}}
.nav{view-transition-name:nav}::view-transition-group(nav){animation-duration:0s}
.route-enter .card,.route-enter .nudge,.route-enter h1,.route-enter .item,.route-enter details.sec,.route-enter .auth{animation:rise .22s cubic-bezier(.16,1,.3,1) both;animation-delay:calc(var(--d,0) * 16ms)}
@keyframes rise{from{opacity:0;transform:translateY(8px)}}
.route-enter .bar>i{transform-origin:left;animation:barGrow .4s cubic-bezier(.2,.8,.2,1) both}
@keyframes barGrow{from{transform:scaleX(0)}}
.route-enter .cal button.day,.route-enter .heat i,.route-enter .heat span{animation:fadeIn .2s ease both;animation-delay:calc(var(--d,0) * 6ms)}
@keyframes fadeIn{from{opacity:0;transform:scale(.8)}}
.btn{transition:transform .12s ease,filter .15s ease,background .15s ease,box-shadow .2s ease}
.btn:hover{filter:brightness(1.08);box-shadow:0 6px 18px rgba(50,108,229,.28)}
.btn:active{transform:scale(.96)}
.btn.ghost:hover{box-shadow:none}
.nav .tab{transition:background .2s,color .2s}
.card{transition:box-shadow .25s ease,transform .25s ease}
a.day,button.day{transition:transform .15s ease,background .2s}
button.day:hover{transform:translateY(-2px)}
.item{transition:background .2s}.item:hover{background:color-mix(in srgb,var(--brand) 6%,transparent)}
dialog[open]{animation:dlgIn .28s cubic-bezier(.16,1,.3,1)}
dialog::backdrop{background:rgba(5,10,28,.5);backdrop-filter:blur(3px);animation:fadeBack .25s ease}
@keyframes dlgIn{from{opacity:0;transform:translateY(14px) scale(.96)}}
@keyframes fadeBack{from{opacity:0}}
#toast{transition:opacity .3s,transform .35s cubic-bezier(.16,1,.3,1)}
.timer-pill.on{animation:pillPulse 2s ease-in-out infinite}
@keyframes pillPulse{0%,100%{box-shadow:0 0 0 0 rgba(18,161,80,.45)}50%{box-shadow:0 0 0 6px rgba(18,161,80,0)}}
.clock.run{animation:clockGlow 2s ease-in-out infinite}
@keyframes clockGlow{50%{text-shadow:0 0 22px rgba(50,108,229,.45)}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{animation-duration:.01ms!important;animation-delay:0s!important;transition-duration:.01ms!important}::view-transition-group(*),::view-transition-old(*),::view-transition-new(*){animation:none!important}}
.intro-brand{display:inline-flex;align-items:center;gap:.5rem}.intro-brand .logo{width:26px;height:auto;filter:none}
.auth{padding-top:1.2rem}
@media (max-width:880px){.cap.hero{width:auto}.cap.hero .cta .btn{flex:1}}

/* ---- card glow + life ---- */
@property --ang{syntax:'<angle>';initial-value:0deg;inherits:false}
.card{position:relative}
.card::before{content:'';position:absolute;inset:0;border-radius:inherit;pointer-events:none;opacity:0;transition:opacity .35s ease;
  background:radial-gradient(420px circle at var(--mx,50%) var(--my,50%),color-mix(in srgb,var(--brand) 16%,transparent),transparent 62%)}
.card::after{content:'';position:absolute;inset:-1px;border-radius:inherit;padding:1.5px;pointer-events:none;opacity:0;transition:opacity .35s ease;
  background:conic-gradient(from var(--ang),transparent 0 62%,var(--brand) 80%,#9dc0ff 90%,transparent 100%);
  -webkit-mask:linear-gradient(#000 0 0) content-box,linear-gradient(#000 0 0);-webkit-mask-composite:xor;mask:linear-gradient(#000 0 0) content-box exclude,linear-gradient(#000 0 0);
  }
.card:hover::after{animation:spinAng 4.5s linear infinite}
@keyframes spinAng{to{--ang:360deg}}
.card:hover{transform:translateY(-3px);border-color:color-mix(in srgb,var(--brand) 45%,var(--line));
  box-shadow:0 0 0 1px color-mix(in srgb,var(--brand) 25%,transparent),0 14px 40px -12px color-mix(in srgb,var(--brand) 55%,transparent)}
.card:hover::before,.card:hover::after{opacity:1}
.card.side:hover,#calGrid .card:hover,.lesson .card:hover{transform:none}
.timer-hero::after{opacity:.55}.timer-hero:hover::after{opacity:1;animation-duration:6s}
.timer-hero{box-shadow:0 0 0 1px color-mix(in srgb,var(--brand) 22%,transparent),0 12px 50px -16px color-mix(in srgb,var(--brand) 60%,transparent)}
.stat .big{transition:text-shadow .3s}
.stat:hover .big{text-shadow:0 0 22px color-mix(in srgb,var(--brand) 70%,transparent)}
.bar>i{position:relative;overflow:hidden;box-shadow:0 0 12px color-mix(in srgb,var(--brand) 70%,transparent)}
.bar>i::after{content:'';position:absolute;inset:0;background:linear-gradient(90deg,transparent,rgba(255,255,255,.5),transparent);transform:translateX(-100%)}
.card:hover .bar>i::after,details.sec:hover .bar>i::after{animation:shimmer 1.6s ease-in-out infinite}
@keyframes shimmer{60%,100%{transform:translateX(100%)}}
.heat i:not([data-l="0"]){box-shadow:0 0 6px color-mix(in srgb,var(--brand) 55%,transparent)}
.heat i{transition:transform .15s}.heat i:hover{transform:scale(1.5);position:relative;z-index:2}
.nudge{position:relative;transition:box-shadow .3s}
.nudge.bad{animation:nudgePulse 2.4s ease-in-out infinite}
.nudge.ok{box-shadow:0 0 28px -8px color-mix(in srgb,var(--ok) 70%,transparent)}
.nudge.warn{box-shadow:0 0 28px -8px color-mix(in srgb,var(--warn) 70%,transparent)}
@keyframes nudgePulse{0%,100%{box-shadow:0 0 0 0 color-mix(in srgb,var(--bad) 40%,transparent)}50%{box-shadow:0 0 28px -4px color-mix(in srgb,var(--bad) 60%,transparent)}}
.nudge.behind{animation:nudgePulse 2.4s ease-in-out infinite}
.clock{transition:text-shadow .4s}
.chip{transition:transform .15s,box-shadow .2s}.chip:hover{transform:translateY(-1px);box-shadow:0 0 12px color-mix(in srgb,var(--brand) 40%,transparent)}
.vdot.on{box-shadow:0 0 6px var(--ok)}
@keyframes dotPulse{50%{box-shadow:0 0 14px var(--ok)}}
.pl{animation:badgeIn .4s cubic-bezier(.2,.9,.3,1.4) both}
@keyframes badgeIn{from{transform:scale(.5);opacity:0}}
button.day.today{box-shadow:0 0 0 2px color-mix(in srgb,var(--brand) 55%,transparent),0 0 18px -2px color-mix(in srgb,var(--brand) 60%,transparent)}
button.day.sel{box-shadow:0 0 22px -2px color-mix(in srgb,var(--brand) 70%,transparent)}
.btn:not(.ghost){background-image:linear-gradient(135deg,color-mix(in srgb,#fff 14%,transparent),transparent 55%)}
@media (hover:none){.card:hover{transform:none}}
@media (prefers-reduced-motion:reduce){.card::after,.bar>i::after,.nudge.bad,.nudge.behind,.vdot.on{animation:none!important}}

/* ---- lesson layout: full-width text, resources in a slide-over drawer ---- */
main:has(.with-side){max-width:1360px}
.with-side{display:block}
.with-side .lesson{max-width:none}
.lesson .md{font-size:1.04rem;line-height:1.72}
.side-handle{position:fixed;right:0;top:42%;z-index:25;writing-mode:vertical-rl;padding:.9rem .55rem;border:1px solid var(--line);border-right:0;border-radius:12px 0 0 12px;background:var(--brand);color:var(--brand-ink);font:600 .85rem Inter,system-ui,sans-serif;cursor:pointer;box-shadow:0 8px 30px -8px color-mix(in srgb,var(--brand) 70%,transparent);transition:padding .2s,transform .2s,opacity .2s}
.side-handle:hover{padding-right:.85rem}
.side-handle.hide{opacity:0;pointer-events:none;transform:translateX(100%)}
.side-backdrop{position:fixed;inset:0;z-index:28;background:rgba(5,10,28,.45);backdrop-filter:blur(2px);opacity:0;pointer-events:none;transition:opacity .25s}
.side-backdrop.on{opacity:1;pointer-events:auto}
aside.side-tabs.card{position:fixed;top:0;right:0;bottom:0;z-index:30;width:min(400px,92vw);max-height:none;border-radius:16px 0 0 16px;overflow:auto;padding:1rem;transform:translateX(106%);transition:transform .35s cubic-bezier(.16,1,.3,1),box-shadow .3s;box-shadow:none}
aside.side-tabs.card.open,aside.side-tabs.card.open:hover{transform:none;box-shadow:-20px 0 60px -20px rgba(0,0,0,.55)}
aside.side-tabs.card:hover{transform:translateX(106%)}
aside.side-tabs.card::before,aside.side-tabs.card::after{display:none}
.side-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:.6rem}
@media (max-width:1000px){aside.side-tabs.card{position:fixed;max-height:none}}
a.vid.has-img{flex-direction:row;align-items:flex-start;gap:.75rem}
a.vid .vthumb{width:150px;aspect-ratio:16/9;object-fit:cover;border-radius:8px;flex:none;background:#0b0f17}
a.vid .vbody{overflow-wrap:anywhere;display:flex;flex-direction:column;gap:.15rem;align-items:flex-start;min-width:0}
@media(max-width:520px){a.vid.has-img{flex-direction:column}a.vid .vthumb{width:100%}}

/* ===== v2 motion: expand + light-up on hover, nav glow, ambient effects ===== */
:root{--glow:color-mix(in srgb,var(--brand) 55%,transparent)}
/* cards expand a little more and light up */
.card{transition:box-shadow .3s ease,transform .3s cubic-bezier(.2,.8,.2,1),border-color .3s,background-color .3s}
.card:hover{transform:translateY(-4px) scale(1.018)}
.card.side:hover,#calGrid .card:hover,.lesson .card:hover,.timer-hero:hover{transform:none}
.timer-hero:hover{transform:translateY(-2px) scale(1.008)}
/* curriculum section boxes */
details.sec{position:relative;transition:transform .3s cubic-bezier(.2,.8,.2,1),box-shadow .3s,border-color .3s,background-color .3s}
details.sec::before{content:'';position:absolute;inset:0;border-radius:inherit;pointer-events:none;opacity:0;transition:opacity .35s;
  background:radial-gradient(380px circle at var(--mx,50%) var(--my,0%),color-mix(in srgb,var(--brand) 15%,transparent),transparent 65%)}
details.sec:hover{transform:scale(1.012);border-color:color-mix(in srgb,var(--brand) 55%,var(--line));z-index:2;
  box-shadow:0 0 0 1px color-mix(in srgb,var(--brand) 28%,transparent),0 12px 36px -10px var(--glow)}
details.sec:hover::before{opacity:1}
details.sec[open]:hover{transform:none}
details.sec>summary{transition:background .25s}
details.sec>summary:hover .bar>i{filter:brightness(1.25)}
/* lesson rows light up and nudge right */
.item{transition:background .2s,transform .25s cubic-bezier(.2,.8,.2,1),box-shadow .25s;position:relative}
.item:hover{background:color-mix(in srgb,var(--brand) 11%,transparent);transform:translateX(5px);box-shadow:inset 3px 0 0 var(--brand)}
.item a{transition:color .2s,text-shadow .2s}.item:hover a{text-shadow:0 0 14px var(--glow)}
.item input[type=checkbox]{transition:transform .2s}.item input[type=checkbox]:hover{transform:scale(1.25)}
.item input[type=checkbox]:checked{animation:pop .35s ease}
@keyframes pop{50%{transform:scale(1.5)}}
/* resource + link cards */
a.vid{transition:transform .3s cubic-bezier(.2,.8,.2,1),box-shadow .3s,border-color .3s,background-color .3s}
a.vid:hover{transform:translateY(-3px) scale(1.025);box-shadow:0 0 0 1px color-mix(in srgb,var(--brand) 30%,transparent),0 12px 30px -10px var(--glow);background:color-mix(in srgb,var(--brand) 7%,var(--surface))}
a.vid .vthumb{transition:transform .4s cubic-bezier(.2,.8,.2,1),filter .3s}
a.vid:hover .vthumb{transform:scale(1.07);filter:brightness(1.12) saturate(1.15)}
/* top pages bar */
.nav{transition:box-shadow .3s}
.nav::after{content:'';position:absolute;left:0;right:0;bottom:-1px;height:2px;pointer-events:none;
  background:linear-gradient(90deg,transparent,var(--brand),#9dc0ff,var(--brand),transparent);opacity:.55}
@keyframes navflow{to{background-position:-200% 0}}
.nav a.tab{position:relative;overflow:hidden;transition:transform .25s cubic-bezier(.2,.8,.2,1),color .2s,background .25s,box-shadow .25s}
.nav a.tab::before{content:'';position:absolute;inset:0;border-radius:inherit;opacity:0;transition:opacity .25s;pointer-events:none;
  background:radial-gradient(90px circle at var(--mx,50%) var(--my,50%),color-mix(in srgb,var(--brand) 35%,transparent),transparent 70%)}
.nav a.tab::after{content:'';position:absolute;left:50%;bottom:3px;height:2px;width:0;background:var(--brand);border-radius:2px;transform:translateX(-50%);transition:width .3s cubic-bezier(.2,.8,.2,1);box-shadow:0 0 8px var(--brand)}
.nav a.tab:hover{transform:translateY(-2px) scale(1.08);color:var(--ink);background:color-mix(in srgb,var(--brand) 14%,var(--bg));box-shadow:0 6px 20px -6px var(--glow)}
.nav a.tab:hover::before{opacity:1}.nav a.tab:hover::after,.nav a.tab.on::after{width:60%}
.nav a.tab.on{box-shadow:0 0 18px -6px var(--glow)}
.nav .brand{transition:transform .3s cubic-bezier(.2,.8,.2,1),filter .3s}
.nav .brand:hover{transform:scale(1.06);filter:drop-shadow(0 0 10px var(--glow));text-decoration:none}
.nav .brand .logo{transition:transform .6s cubic-bezier(.2,.8,.2,1)}.nav .brand:hover .logo{transform:rotate(18deg) scale(1.12)}
.nav .chip,.nav .timer-pill{transition:transform .25s cubic-bezier(.2,.8,.2,1),box-shadow .25s}
.nav .chip:hover,.nav .timer-pill:hover{transform:translateY(-2px) scale(1.08);box-shadow:0 6px 18px -6px var(--glow)}
.nav-in>*{animation:navIn .6s cubic-bezier(.16,1,.3,1) both}
.nav-in>*:nth-child(2){animation-delay:.05s}.nav-in>*:nth-child(3){animation-delay:.1s}.nav-in>*:nth-child(4){animation-delay:.15s}.nav-in>*:nth-child(5){animation-delay:.2s}.nav-in>*:nth-child(6){animation-delay:.25s}
@keyframes navIn{from{opacity:0;transform:translateY(-10px)}}
/* buttons: lift, glow, press, ripple */
.btn{position:relative;overflow:hidden;transition:transform .2s cubic-bezier(.2,.8,.2,1),box-shadow .25s,filter .2s}
.btn:hover:not(:disabled){transform:translateY(-2px) scale(1.04)}
.btn:active:not(:disabled){transform:scale(.97)}
.btn .rip{position:absolute;border-radius:50%;background:rgba(255,255,255,.45);transform:scale(0);animation:rip .6s ease-out forwards;pointer-events:none}
@keyframes rip{to{transform:scale(4);opacity:0}}
/* calendar days, chips, heatmap */
button.day{transition:transform .2s cubic-bezier(.2,.8,.2,1),box-shadow .25s,border-color .2s,background .2s}
button.day:hover{transform:translateY(-3px) scale(1.07);box-shadow:0 8px 22px -8px var(--glow);z-index:2;position:relative}
.chip:hover{transform:translateY(-2px) scale(1.07)}
/* page headings + ambient background */
h1{background:linear-gradient(90deg,var(--ink) 0,var(--ink) 55%,color-mix(in srgb,var(--brand) 70%,var(--ink)) 100%);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;width:fit-content;max-width:100%}
body::before{content:'';position:fixed;inset:0;z-index:-1;pointer-events:none;opacity:.5;
  background:radial-gradient(40vmax 40vmax at 15% 10%,color-mix(in srgb,var(--brand) 14%,transparent),transparent 60%),radial-gradient(35vmax 35vmax at 85% 90%,color-mix(in srgb,#a855f7 10%,transparent),transparent 60%)}
@keyframes drift{to{transform:translate(4vmax,-3vmax) rotate(6deg)}}
.stat .big{transition:text-shadow .3s,transform .3s cubic-bezier(.2,.8,.2,1)}.stat:hover .big{transform:scale(1.08)}
@media (hover:none){.card:hover,details.sec:hover,a.vid:hover,.item:hover,.nav a.tab:hover{transform:none}}
@media (prefers-reduced-motion:reduce){.nav::after,body::before,.nav-in>*{animation:none!important}.card:hover,details.sec:hover,a.vid:hover,.item:hover,.nav a.tab:hover,.btn:hover{transform:none!important}}

/* perf: smoother hover transitions */
.btn{transition:transform .15s ease-out,box-shadow .2s,filter .15s}
.btn:hover:not(:disabled){transform:translateY(-2px) scale(1.05);filter:brightness(1.12);box-shadow:0 8px 22px -4px var(--glow)}
.btn.ghost:hover:not(:disabled){box-shadow:0 6px 18px -6px var(--glow);border-color:var(--brand)}
.lesson .md pre code,.guide .md pre code{font-size:inherit}

.codewrap{position:relative;margin:1em 0}.codewrap pre{margin:0;padding-right:3rem}
.copybtn{position:absolute;top:8px;right:8px;width:32px;height:32px;display:grid;place-items:center;border-radius:8px;border:1px solid rgba(255,255,255,.14);background:rgba(255,255,255,.06);color:#9fb0c8;cursor:pointer;opacity:.55;transition:opacity .12s,background .12s,color .12s,transform .12s}
.codewrap:hover .copybtn,.copybtn:focus-visible{opacity:1}
.copybtn:hover{background:rgba(122,162,255,.22);color:#fff;transform:scale(1.08)}
.copybtn:active{transform:scale(.94)}
.copybtn.ok{opacity:1;color:#4ade80;border-color:#4ade80;background:rgba(74,222,128,.15)}
@media (hover:none){.copybtn{opacity:1}}

.title-row{display:flex;align-items:flex-start;justify-content:space-between;gap:1rem}.title-row h1{margin:0 0 .5em;min-width:0}.skipvid{flex:none;white-space:nowrap;margin-top:.2rem}
@media (max-width:560px){.title-row{flex-direction:column;gap:.3rem}}

.hero-row{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);gap:1rem;margin-top:1rem;align-items:stretch}
.hero-row .timer-hero{max-width:none;margin:0;display:flex;flex-direction:column;justify-content:center}
.stats2{display:grid;grid-template-columns:1fr 1fr;gap:1rem;grid-auto-rows:1fr}
.stats2 .stat{display:flex;flex-direction:column;justify-content:center}
@media (max-width:900px){.hero-row{grid-template-columns:1fr}}
@media (max-width:480px){.stats2{grid-template-columns:1fr 1fr;gap:.6rem}}

.chan-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:1rem;margin-top:1rem}
a.chan{display:flex;gap:.9rem;align-items:flex-start;color:inherit;text-decoration:none}
a.chan:hover{text-decoration:none;transform:translateY(-3px) scale(1.015);box-shadow:0 12px 30px -12px color-mix(in srgb,var(--brand) 55%,transparent);border-color:color-mix(in srgb,var(--brand) 55%,var(--line))}
.chan-ic{font-size:1.7rem;line-height:1;flex:none;width:2.6rem;height:2.6rem;display:grid;place-items:center;border-radius:12px;background:var(--bg)}
.chan-tx h2{margin:0 0 .25rem;font-size:1.02rem}.chan-tx p{margin:0 0 .45rem;color:var(--muted);font-size:.88rem;line-height:1.4}
.disc-new{margin:1rem 0}.disc-new input,.disc-new textarea{width:100%;margin-bottom:.6rem;font:inherit}.disc-new textarea{resize:vertical;min-height:90px}
.thread-list{display:grid;gap:.7rem;margin-top:1rem}
a.thread{display:flex;justify-content:space-between;gap:1rem;color:inherit;text-decoration:none;padding:.9rem 1.1rem}
a.thread:hover{text-decoration:none;transform:translateY(-2px) scale(1.01);border-color:color-mix(in srgb,var(--brand) 55%,var(--line))}
.thread-main{min-width:0}.thread-main h3{margin:0 0 .2rem;font-size:1rem}.thread-main p{margin:0 0 .3rem;color:var(--muted);font-size:.88rem;overflow:hidden;text-overflow:ellipsis;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical}
.thread-n{flex:none;text-align:center;min-width:3.2rem;color:var(--muted);font-size:.75rem}.thread-n b{display:block;font-size:1.25rem;color:var(--ink)}
.post{margin-bottom:.7rem}.post.op{border-left:4px solid var(--brand)}
.post-meta{display:flex;align-items:center;gap:.4rem;flex-wrap:wrap;margin-bottom:.6rem}.post-meta .avatar{width:26px;height:26px;font-size:.78rem}
.post-body{line-height:1.6;overflow-wrap:anywhere}.post-body pre{background:#0f1420;color:#e6edf7;padding:.8rem 1rem;border-radius:8px;overflow:auto;margin:.6rem 0}
.post-body code{background:var(--bg);padding:.1em .35em;border-radius:4px}.post-body pre code{background:none;padding:0}
.linkbtn{background:none;border:0;color:var(--muted);cursor:pointer;font-size:.8rem;margin-left:auto;padding:.1rem .3rem}.linkbtn:hover{color:var(--bad,#d33);text-decoration:underline}
@media (max-width:640px){.chan-grid{grid-template-columns:1fr}}
.nav-in{flex-wrap:nowrap;gap:.1rem}.nav .brand{white-space:nowrap;margin-right:.4rem}.nav a.tab{padding:.4em .6em;white-space:nowrap}
.nav a.tab[href="#/settings"]{max-width:8rem;overflow:hidden;text-overflow:ellipsis}
.timer-pill,.nav .chip{white-space:nowrap;flex:none}
@media (max-width:900px){.nav-in{flex-wrap:wrap}}

/* discussions: chat */
.disc-warn{display:flex;gap:.5rem;align-items:flex-start;margin:.5rem 0;padding:.55rem .8rem;border-radius:10px;font-size:.88rem;line-height:1.4;background:color-mix(in srgb,#f59e0b 14%,var(--surface));border:1px solid color-mix(in srgb,#f59e0b 55%,var(--line));color:var(--ink)}
.chat{padding:0;overflow:hidden;display:flex;flex-direction:column;margin-top:.7rem}
.chat-log{height:clamp(320px,calc(100vh - 380px),640px);overflow-y:auto;padding:1rem 1.1rem;display:flex;flex-direction:column;gap:.75rem;scroll-behavior:smooth}
.chat-empty{margin:auto;text-align:center}
.msg{display:flex;gap:.6rem;align-items:flex-start}.msg .avatar{flex:none;margin:0;width:30px;height:30px}
.msg-main{min-width:0;max-width:min(760px,100%)}.msg-head{display:flex;align-items:center;gap:.5rem;margin-bottom:.1rem}.msg-head a{font-weight:700;font-size:.9rem}
.msg-body{line-height:1.5;overflow-wrap:anywhere;background:var(--bg);padding:.45rem .7rem;border-radius:4px 12px 12px 12px;display:inline-block}
.msg.mine .msg-body{background:color-mix(in srgb,var(--brand) 18%,var(--bg))}
.msg-body pre{background:#0f1420;color:#e6edf7;padding:.7rem .9rem;border-radius:8px;overflow:auto;margin:.4rem 0}.msg-body code{background:rgba(127,127,127,.18);padding:.1em .35em;border-radius:4px}.msg-body pre code{background:none;padding:0}
.chat-form{display:flex;gap:.6rem;padding:.8rem 1rem;border-top:1px solid var(--line);align-items:flex-end}
.chat-in,.disc-new input,.disc-new textarea{flex:1;font:inherit;background:#fff;color:#111;border:1px solid #c5ccd8;border-radius:10px;padding:.55rem .7rem;resize:none;min-height:46px;max-height:160px}
.chat-in::placeholder{color:#6b7280}.chat-in:focus{outline:2px solid var(--brand);outline-offset:0}
.chat .err{padding:0 1rem .6rem;min-height:0}

.exam-book{display:flex;gap:1rem;align-items:flex-start;margin:1rem 0 .4rem;border-left:4px solid var(--brand)}
.eb-ic{font-size:1.9rem;line-height:1;flex:none}.eb-tx{min-width:0}
.eb-tip{display:flex;gap:.5rem;align-items:flex-start;margin:0 0 .8rem;padding:.55rem .8rem;border-radius:10px;font-size:.9rem;line-height:1.45;background:color-mix(in srgb,#f59e0b 14%,var(--surface));border:1px solid color-mix(in srgb,#f59e0b 55%,var(--line))}

.labnote{display:flex;gap:.5rem;align-items:flex-start;margin:.2rem 0 1rem;padding:.55rem .8rem;border-radius:10px;font-size:.9rem;line-height:1.45;background:color-mix(in srgb,var(--brand) 10%,var(--surface));border:1px solid color-mix(in srgb,var(--brand) 40%,var(--line))}
.lesson .md details{margin:.55rem 0;border:1px solid var(--line);border-radius:10px;background:var(--surface);overflow:hidden}
.lesson .md details>summary{cursor:pointer;font-weight:700;padding:.6rem .9rem;list-style:none;display:flex;gap:.5rem;align-items:baseline}
.lesson .md details>summary::-webkit-details-marker{display:none}
.lesson .md details>summary::before{content:"▸";color:var(--brand);transition:transform .15s}
.lesson .md details[open]>summary::before{transform:rotate(90deg)}
.lesson .md details[open]>summary{border-bottom:1px solid var(--line);background:var(--bg)}
.lesson .md details>*:not(summary){margin-left:.9rem;margin-right:.9rem}
.lesson .md details>p:last-child,.lesson .md details>pre:last-child{margin-bottom:.8rem}

.site-foot{max-width:1100px;margin:-2.5rem auto 5rem;padding:0 1rem;display:flex;flex-wrap:wrap;gap:.6rem 1.2rem;justify-content:space-between;align-items:center;font-size:.78rem;color:var(--muted,#8a93a6)}
.site-foot .coffee{color:inherit;text-decoration:none;border:1px solid currentColor;border-radius:999px;padding:.25rem .8rem;opacity:.85}
.site-foot .coffee:hover{opacity:1;color:var(--accent,#3b82f6)}

/* Emphasised Curriculum tab */
.nav a.tab.hero{font-weight:800;letter-spacing:.01em;color:transparent;background:linear-gradient(110deg,#60a5fa,#a78bfa 35%,#f472b6 65%,#fbbf24) 0 0/220% 100%;-webkit-background-clip:text;background-clip:text;
  border:1px solid color-mix(in srgb,var(--brand) 55%,transparent);box-shadow:0 0 16px -4px var(--glow);animation:heroShift 6s linear infinite}
.nav a.tab.hero .hero-ic{display:inline-block;margin-right:.3em;font-size:.8em;-webkit-text-fill-color:#fbbf24;animation:heroPulse 2.4s ease-in-out infinite}
.nav a.tab.hero:hover{background:linear-gradient(110deg,#60a5fa,#a78bfa 35%,#f472b6 65%,#fbbf24) 0 0/220% 100%;-webkit-background-clip:text;background-clip:text;box-shadow:0 6px 22px -4px var(--glow)}
.nav a.tab.hero.on{box-shadow:0 0 22px -2px var(--glow)}
@keyframes heroShift{to{background-position:220% 0}}
@keyframes heroPulse{50%{transform:scale(1.35) rotate(20deg);opacity:.8}}
@media (prefers-reduced-motion:reduce){.nav a.tab.hero,.nav a.tab.hero .hero-ic{animation:none!important}}