/* Calcali app shell. One stylesheet for phone, tablet and desktop.
   Spacing follows the Fibonacci steps 5, 8, 13, 21, 34, 55. Corners are Apple-style squircles. */
*{box-sizing:border-box}
html,body{height:100%;margin:0}
body{background:var(--desk);color:var(--ink);font-family:var(--sans);-webkit-tap-highlight-color:transparent;overscroll-behavior-y:none}
button,input,select,textarea{font-family:inherit;font-size:inherit;color:var(--ink)}
button{cursor:pointer;background:none;border:0;padding:0;display:inline-flex;align-items:center;justify-content:center;gap:6px;line-height:1}
a{color:inherit}
input,select,textarea{-webkit-text-fill-color:var(--ink);caret-color:var(--ink)}
:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
[hidden]{display:none!important}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

/* ---------- shell ----------
   Phones: content + a tab bar at the bottom. 760px+: a side rail pinned to the left edge that never
   moves between pages; content is centred in the space to its right. 1280px+: an extra column on feeds. */
body{background-color:var(--desk)}
.shell{display:flex;min-height:100dvh;justify-content:center;padding-left:var(--railw)}
.shell.norail{padding-left:0}
.rail{display:none}
.main{flex:1;min-width:0;max-width:640px;width:100%;display:flex;flex-direction:column;min-height:100dvh;position:relative;padding-bottom:calc(var(--tabbar) + env(safe-area-inset-bottom,0px))}
.main.mwide{max-width:1120px}
.main.mfull{max-width:none}
.main.mboard{max-width:none;padding:0!important}
.aside{display:none}
.tabbar{position:fixed;left:0;right:0;bottom:0;z-index:50;display:flex;align-items:center;justify-content:space-around;padding:6px 8px calc(6px + env(safe-area-inset-bottom,0px));background:var(--paper);border-top:2px solid var(--line)}
:root{--tabbar:66px}
.tab{flex:1;max-width:76px;height:52px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;text-decoration:none;font-size:11px;color:var(--muted);border-radius:var(--r1);position:relative}
.tab svg{display:block}
.tab[aria-current=page]{color:var(--ink);font-weight:700}
.tab[aria-current=page] svg{stroke-width:2.6}
.tab.ask{flex:0 0 54px;width:54px;height:54px;border-radius:19px;corner-shape:squircle;background:var(--ink);color:var(--onink)}
.tabav{display:flex;height:28px;align-items:center}
.tab[aria-current=page] .tabav .avw{outline:2px solid var(--ink);outline-offset:1px;border-radius:999px}
.badge{min-width:18px;height:18px;padding:0 5px;border-radius:999px;background:var(--bad);color:#1F2328;font-size:10px;font-weight:700;display:inline-flex;align-items:center;justify-content:center;border:2px solid var(--paper);line-height:1}
/* full-screen pages (question page, ask, a whiteboard) hide the tab bar on phones */
.immersive .tabbar{display:none}
.immersive{--tabbar:0px}

@media (min-width:760px){
  :root{--tabbar:0px;--railw:84px}
  .tabbar{display:none}
  .rail{display:flex;flex-direction:column;gap:4px;position:fixed;left:0;top:0;bottom:0;z-index:40;width:var(--railw);padding:21px 13px;border-right:2px solid var(--line);background:color-mix(in srgb,var(--paper) 82%,transparent);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px);overflow-y:auto;scrollbar-width:none}
  .shell.norail .rail{display:none}
  .rail .logo{display:flex;align-items:center;gap:10px;height:44px;padding:0 8px;margin-bottom:13px;user-select:none}
  .rail .logo img{flex-shrink:0}
  .rail .logo b{display:none;font-size:22px;letter-spacing:-.03em}
  .rail a.nav{display:flex;align-items:center;gap:13px;height:48px;padding:0 15px;border-radius:var(--r1);corner-shape:squircle;text-decoration:none;font-size:15px;color:var(--muted);position:relative;flex-shrink:0}
  .rail a.nav>svg,.rail a.nav .ic{width:28px;height:28px;display:flex;align-items:center;justify-content:center;flex-shrink:0;position:relative}
  .rail a.nav>svg{padding:2px}
  .rail a.nav span.l{display:none;white-space:nowrap}
  .rail a.nav:hover{background:var(--soft)}
  .rail a.nav[aria-current=page]{color:var(--ink);font-weight:700;background:var(--soft)}
  .rail a.nav[aria-current=page] svg{stroke-width:2.6}
  .rail a.nav .badge{position:absolute;top:-6px;left:16px}
  .rail .askbtn{margin-top:8px;height:48px;border-radius:var(--r1);corner-shape:squircle;background:var(--ink);color:var(--onink);font-weight:600;text-decoration:none;display:flex;align-items:center;justify-content:center;gap:8px;flex-shrink:0}
  .rail .askbtn span{display:none}
  .rail .grow{flex:1;min-height:13px}
  .main{padding:0 21px}
  .main.mfull{padding:0}
  .head .bell{display:none}
}
@media (min-width:1100px){
  :root{--railw:248px}
  .rail .logo b,.rail a.nav span.l,.rail .askbtn span{display:inline}
}
@media (min-width:1280px){
  .aside{display:flex;flex-direction:column;gap:13px;width:320px;flex-shrink:0;padding:21px 21px 21px 0;position:sticky;top:0;height:100dvh;overflow:auto}
  .no-aside .aside{display:none}
}

/* ---------- headers ---------- */
.head{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:8px;min-height:62px;padding:calc(10px + env(safe-area-inset-top,0px)) 13px 10px;background:color-mix(in srgb,var(--desk) 88%,transparent);-webkit-backdrop-filter:blur(8px);backdrop-filter:blur(8px)}
.head h1{margin:0;font-size:20px;letter-spacing:-.02em;font-weight:700;line-height:1.15;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.htitle{display:flex;flex-direction:column;min-width:0;flex-shrink:1}
.htitle span{font-size:12px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;display:flex;align-items:center;gap:5px}
.head .sp{flex:1}
.brand{display:flex;align-items:center;gap:8px;user-select:none}
.brand b{font-size:22px;letter-spacing:-.03em}
h1.onlywide{display:none}
@media (min-width:760px){.head .brand{display:none}h1.onlywide{display:block}.head{padding-top:21px}}
.iconbtn{width:40px;height:40px;border-radius:999px;border:2px solid var(--line);background:var(--paper);position:relative;flex-shrink:0;text-decoration:none;display:inline-flex;align-items:center;justify-content:center;color:var(--ink);padding:0}
.iconbtn svg{display:block;flex-shrink:0}
.iconbtn .badge{position:absolute;top:-5px;right:-7px}
.hub{display:flex;gap:6px;padding:0 13px 8px;overflow-x:auto;scrollbar-width:none}
.hub::-webkit-scrollbar{display:none}
.hub .fchip svg{display:block}
@media (min-width:760px){.hub{display:none}}

/* ---------- surfaces ---------- */
.card{background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;padding:13px;display:flex;flex-direction:column;gap:8px}
.stack{display:flex;flex-direction:column;gap:8px}
.pad{padding:0 8px}
.section-title{font-size:13px;font-weight:700;color:var(--muted);text-transform:none;margin:13px 5px 3px;display:flex;align-items:center;gap:8px}
.muted{color:var(--muted)}
.small{font-size:12px}
.hrow{display:flex;align-items:center;gap:8px}
.wrap{flex-wrap:wrap}
.grow{flex:1;min-width:0}
.center{text-align:center}
.empty{padding:34px 21px;text-align:center;color:var(--muted);font-size:14px;line-height:1.5}
.empty b{display:block;color:var(--ink);font-size:16px;margin-bottom:5px}

/* ---------- buttons, chips, tabs ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:44px;padding:0 18px;border-radius:var(--r1);corner-shape:squircle;background:var(--ink);color:var(--onink);font-weight:600;font-size:15px;white-space:nowrap;text-decoration:none}
.btn.sec{background:var(--paper);color:var(--ink);border:2px solid var(--line)}
.btn.ghost{background:transparent;color:var(--ink)}
.btn.small{height:34px;padding:0 13px;font-size:13px;border-radius:10px}
.btn.block{width:100%}
.btn.danger{background:var(--bad);color:var(--ink)}
.btn:disabled{opacity:.5;cursor:default}
.chips{display:flex;gap:6px;overflow-x:auto;scrollbar-width:none;padding:2px 0}
.chips::-webkit-scrollbar{display:none}
.fchip{flex-shrink:0;height:34px;padding:0 13px;border-radius:999px;background:var(--paper);border:2px solid var(--line);font-size:13px;font-weight:500;white-space:nowrap;text-decoration:none;display:inline-flex;align-items:center;gap:6px}
.fchip[aria-pressed=true],.fchip.on{background:var(--ink);border-color:var(--ink);color:var(--onink)}
.tabs{display:flex;border-bottom:2px solid var(--line);gap:2px;overflow-x:auto;scrollbar-width:none}
.tabs::-webkit-scrollbar{display:none}
.tabs button,.tabs a{flex-shrink:0;height:44px;padding:0 13px;border-bottom:3px solid transparent;margin-bottom:-2px;font-size:14px;font-weight:500;color:var(--muted);text-decoration:none;display:inline-flex;align-items:center}
.tabs [aria-selected=true]{border-bottom-color:var(--ink);color:var(--ink);font-weight:700}
.tabs.grow-tabs button{flex:1}
.topicchip{display:inline-flex;align-items:center;gap:5px;height:24px;padding:0 9px;border-radius:999px;background:var(--soft);font-size:11px;font-weight:600;text-decoration:none;white-space:nowrap}
.pill{padding:4px 9px;border-radius:999px;font-size:11px;font-weight:600;white-space:nowrap;line-height:1.2;color:#1F2328}

/* ---------- forms ---------- */
.field{display:flex;flex-direction:column;gap:5px}
.field>span,.label{font-size:13px;font-weight:600}
.field small{font-size:12px;color:var(--muted);line-height:1.4}
.input,.select,.textarea{height:48px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--field);padding:0 13px;font-size:16px;width:100%}
.textarea{height:auto;min-height:96px;padding:12px 13px;line-height:1.45;resize:vertical}
.select{appearance:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%231F2328' stroke-width='3' stroke-linecap='round'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 13px center;padding-right:36px}
.input.math{font-family:var(--math);font-size:21px}
.input:focus,.select:focus,.textarea:focus{border-color:var(--ink);outline:none}
.form{display:flex;flex-direction:column;gap:13px}
.err{color:var(--badText);font-size:13px;min-height:0}
.ok{color:var(--okText);font-size:13px}
.seg2{display:grid;grid-template-columns:repeat(auto-fit,minmax(90px,1fr));gap:6px}
.opt2{min-height:48px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--field);font-weight:600;font-size:14px;padding:8px;text-align:center;line-height:1.2}
.opt2[aria-pressed=true]{background:var(--ink);border-color:var(--ink);color:var(--onink)}
.check{display:flex;gap:10px;align-items:flex-start;font-size:14px;line-height:1.4}
.check input{width:20px;height:20px;margin:1px 0 0;accent-color:var(--ink)}

/* ---------- avatars ---------- */
.avw{position:relative;display:inline-flex;align-items:center;justify-content:center;flex-shrink:0}
.av{width:32px;height:32px;border-radius:999px;display:inline-flex;align-items:center;justify-content:center;font-weight:700;font-size:12px;flex-shrink:0;line-height:1}

/* ---------- feed cards ---------- */
.feed{display:flex;flex-direction:column;gap:13px;padding:5px 8px 21px}
.pc{background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;padding:13px;display:flex;flex-direction:column;gap:10px;cursor:pointer;text-decoration:none;color:inherit;transition:transform .15s}
.pc:active{transform:scale(.995)}
.pc{container-type:inline-size}
.ph{display:flex;align-items:center;gap:8px;font-size:13px;min-width:0}
.ph .who2{display:flex;flex-direction:column;min-width:0;flex:1;line-height:1.25}
.ph .nm{font-weight:600;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.ph .tm{color:var(--muted);font-size:11px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.ph .tm b{font-weight:600}
.pmeta{display:flex;align-items:center;gap:5px;flex-shrink:0;margin-left:auto}
.tchip{display:inline-flex;align-items:center;gap:5px;height:26px;padding:0 8px 0 2px;border-radius:999px;background:var(--soft);font-size:11px;font-weight:600;text-decoration:none;white-space:nowrap;max-width:150px}
.tchip>span:last-child{overflow:hidden;text-overflow:ellipsis}
.tchip .tsym.sm{height:22px;min-width:22px;border-radius:999px}
.qpill{display:inline-flex;align-items:center;justify-content:center;height:24px;color:#1F2328}
.qpill .ps{display:none;font-size:13px;font-weight:700}
@container (max-width:330px){.tchip>span:last-child{display:none}.tchip{padding:0 2px}}
@container (max-width:430px){.qpill{width:24px;padding:0}.qpill .pw{display:none}.qpill .ps{display:inline}}
.pc .why{font-size:11px;color:var(--muted);display:flex;align-items:center;gap:5px;margin:-4px 0 -2px}
.pc h3{margin:0;font-size:17px;font-weight:600;line-height:1.35;letter-spacing:-.01em;overflow-wrap:anywhere}
.pc .bd{font-size:14px;line-height:1.45;color:var(--ink);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;margin:0}
.thumb{position:relative;border-radius:16px;corner-shape:squircle;overflow:hidden;border:2px solid var(--line);background:var(--board);aspect-ratio:2/1}
.thumb canvas,.thumb img{width:100%;height:100%;display:block;object-fit:cover}
.pc .best{display:flex;gap:8px;align-items:flex-start;background:var(--board);border:2px solid var(--line);border-radius:16px;corner-shape:squircle;padding:8px 10px;font-size:13px;line-height:1.4}
.pc .best .m{font-family:var(--math);font-size:18px}
.pc .acts{display:flex;align-items:center;gap:8px;font-size:12px;color:var(--muted)}
.pc .acts .cnt{display:inline-flex;align-items:center;gap:5px;height:28px;padding:0 11px;border-radius:999px;background:var(--soft);font-weight:700;color:var(--ink)}
.pc .acts .cnt.on{background:var(--ink);color:var(--onink)}
.vote{border:0;background:var(--soft);border-radius:999px;height:28px;padding:0 11px;font-size:12px;font-weight:700;touch-action:none;user-select:none;-webkit-user-select:none}
.vote[aria-pressed=true]{background:var(--ink);color:var(--onink)}
.vote.down{background:var(--ink);color:var(--onink)}
.dots{margin-left:auto;width:32px;height:28px;border-radius:999px;color:var(--muted)}
.dots:hover{background:var(--soft)}
.m i{font-style:italic}.m sup{font-size:.68em;vertical-align:.7em;line-height:0;margin-left:.08em}
.fr{display:inline-flex;flex-direction:column;align-items:center;vertical-align:middle;font-size:.82em;line-height:1.05;margin:0 2px}
.fr>span:first-child{border-bottom:1.5px solid currentColor;padding:0 2px}
.mathtext{font-family:var(--math);font-size:1.22em}

/* circles row (people you follow who posted) */
.circles{display:flex;gap:13px;overflow-x:auto;padding:5px 13px 8px;scrollbar-width:none}
.circles::-webkit-scrollbar{display:none}
.circle{display:flex;flex-direction:column;align-items:center;gap:5px;font-size:11px;text-decoration:none;width:64px;flex-shrink:0}
.circle span.n{max-width:64px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}

/* ---------- discover grid ---------- */
.grid3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;padding:0 8px}
@media (min-width:760px){.grid3{grid-template-columns:repeat(4,minmax(0,1fr));gap:8px}}
.tile{position:relative;aspect-ratio:1/1;border-radius:16px;corner-shape:squircle;background:var(--paper);border:2px solid var(--line);overflow:hidden;text-decoration:none;display:block;padding:0}
.tile.framed{border:0;padding:4px}
.tile .tin{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;padding:8px;text-align:center;background:var(--paper);overflow:hidden}
.tile.framed .tin{inset:4px;border-radius:12px;corner-shape:squircle}
.tile canvas{position:absolute;inset:0;width:100%;height:100%}
.tile .tt{font-size:12px;font-weight:600;line-height:1.3;display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden;position:relative;margin-top:10px}
.tile .st{position:absolute;right:6px;top:6px;width:20px;height:20px;border-radius:999px;display:flex;align-items:center;justify-content:center;font-size:11px;font-weight:700;z-index:1;color:#1F2328}
.tile .tp{position:absolute;left:6px;top:6px;z-index:1;display:flex}
.tile .cap{position:absolute;left:0;right:0;bottom:0;padding:4px 6px;font-size:10px;font-weight:600;background:linear-gradient(transparent,color-mix(in srgb,var(--paper) 92%,transparent) 40%);text-align:left;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.people{display:flex;gap:8px;overflow-x:auto;padding:0 8px 5px;scrollbar-width:none}
.people::-webkit-scrollbar{display:none}
.person{flex-shrink:0;width:132px;background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;padding:13px 8px;display:flex;flex-direction:column;align-items:center;gap:6px;text-decoration:none;font-size:13px}
.person .nm{font-weight:600;max-width:110px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.searchbar{display:flex;align-items:center;gap:8px;height:48px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--field);padding:0 13px;margin:0 8px}
.searchbar input{flex:1;border:0;background:transparent;font-size:16px;height:100%;outline:none;min-width:0}

/* ---------- profile ----------
   The banner frames the profile: a strip across the top and a thin edge around the details. */
.prof{padding:0 8px}
.pcard{margin:0 8px;border-radius:var(--r2);corner-shape:squircle;border:2px solid var(--line);background:var(--paper);position:relative;padding:0}
.pcard.hasban{padding:34px 5px 5px;border:0}
.pin{background:var(--paper);border-radius:17px;corner-shape:squircle;padding:13px;display:flex;flex-direction:column;gap:8px}
.pcard.hasban .pin{padding-top:10px}
.ptop{display:flex;align-items:center;gap:13px;min-width:0}
.pav{position:relative;flex-shrink:0;border:0;background:var(--paper);padding:3px;border-radius:999px;display:flex}
.pcard.hasban .pav{margin-top:-44px}
.pav .avedit{position:absolute;right:2px;bottom:2px;width:24px;height:24px;border-radius:999px;background:var(--ink);color:var(--onink);display:flex;align-items:center;justify-content:center;border:2px solid var(--paper)}
.pid{min-width:0;flex:1}
.pname{font-size:20px;font-weight:700;letter-spacing:-.02em;display:flex;align-items:baseline;gap:8px;flex-wrap:wrap;line-height:1.2;overflow-wrap:anywhere}
.pname small{font-size:14px;font-weight:500;color:var(--muted)}
.psub{font-size:12px;color:var(--muted);margin-top:3px;display:flex;flex-wrap:wrap;align-items:center;gap:4px 8px}
.pcur{display:inline-flex;align-items:center;gap:4px;font-weight:600;color:var(--ink)}
.pbio{font-size:14px;line-height:1.45;margin:0;overflow-wrap:anywhere}
.prow{display:flex;align-items:center;gap:8px;flex-wrap:wrap}
.pstats{display:flex;flex-wrap:wrap;gap:4px 13px;font-size:13px;color:var(--muted);flex:1;min-width:0}
.pstats b{color:var(--ink);font-weight:700}
.pstats a{color:inherit;text-decoration:none}
.pstats a:hover b{text-decoration:underline}
.pacts{display:flex;gap:6px;margin-left:auto}
.banbtn{position:absolute;top:5px;right:5px;height:26px;padding:0 9px;border-radius:999px;background:color-mix(in srgb,var(--paper) 88%,transparent);font-size:11px;font-weight:600;gap:4px;z-index:1}
.pcard:not(.hasban) .banbtn{position:static;margin:8px 0 -6px 13px}
.avgrid{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
@media (min-width:480px){.avgrid{grid-template-columns:repeat(5,1fr)}}
.avopt{flex-direction:column;gap:4px;padding:6px 0;border-radius:var(--r1);font-size:11px;font-weight:600;color:var(--muted);border:2px solid transparent}
.avopt svg{width:56px;height:56px}
.avopt[aria-pressed=true]{border-color:var(--ink);color:var(--ink)}
.listrow{display:flex;align-items:center;gap:10px;padding:10px 13px;border-radius:var(--r1);text-decoration:none;color:inherit}
.listrow:hover{background:var(--soft)}
.listrow .t{flex:1;min-width:0}
.listrow .t b{display:block;font-size:14px}
.listrow .t span{font-size:12px;color:var(--muted)}

/* banner picker */
.bgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}
@media (min-width:760px){.bgrid{grid-template-columns:repeat(5,1fr)}}
.bopt{border:2px solid var(--line);border-radius:16px;corner-shape:squircle;height:64px;background-color:var(--soft);position:relative;padding:0;font-size:11px;font-weight:700;display:flex;align-items:flex-end;justify-content:flex-start}
.bopt span{background:var(--paper);border-radius:999px;padding:2px 7px;margin:5px}
.bopt[aria-pressed=true]{border-color:var(--ink);box-shadow:0 0 0 2px var(--ink)}
.bopt[aria-pressed=true]::after{content:'✓';position:absolute;top:5px;right:5px;width:20px;height:20px;border-radius:999px;background:var(--ink);color:var(--onink);font-size:11px;display:flex;align-items:center;justify-content:center}
.colors{display:flex;gap:10px;flex-wrap:wrap}
.cdot{width:40px;height:40px;border-radius:999px;border:2px solid var(--line)}
.cdot[aria-pressed=true]{box-shadow:0 0 0 3px var(--paper),0 0 0 5px var(--ink)}

/* ---------- auth ---------- */
.authwrap{max-width:440px;width:100%;margin:0 auto;padding:34px 13px 55px;display:flex;flex-direction:column;gap:13px}
.authwrap h1{font-size:28px;letter-spacing:-.03em;margin:8px 0 0}
.authwrap p.lead{margin:0;color:var(--muted);line-height:1.5}
.provider{height:52px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--paper);font-weight:600;font-size:15px;width:100%;gap:10px}
.provider.apple{background:#000;color:#FFF;border-color:#000}
.or{display:flex;align-items:center;gap:13px;color:var(--muted);font-size:12px}
.or::before,.or::after{content:'';flex:1;height:2px;background:var(--line)}
.steps{display:flex;gap:5px}
.steps i{flex:1;height:5px;border-radius:3px;background:var(--line)}
.steps i.on{background:var(--ink)}
.code{letter-spacing:.4em;font-size:24px;text-align:center;font-variant-numeric:tabular-nums}

/* ---------- learn ---------- */
.lhero{padding:8px 13px 13px;display:flex;flex-direction:column;gap:10px}
.lhero h1{margin:0;font-size:28px;letter-spacing:-.03em;line-height:1.1}
.lhero p{margin:0;color:var(--muted);line-height:1.5;max-width:600px;font-size:14px}
.curtabs{display:flex;gap:6px;flex-wrap:wrap}
.curtab{display:inline-flex;align-items:center;gap:7px;height:38px;padding:0 14px;border-radius:999px;border:2px solid var(--line);background:var(--paper);text-decoration:none;font-weight:600;font-size:14px}
.curtab.on{border-color:var(--yc);background:color-mix(in srgb,var(--yc) 16%,var(--paper))}
.curtab.on .curdot{background:var(--yc)}
.curtab.uk{--yc:var(--uk)}.curtab.us{--yc:var(--us)}.curtab.caps{--yc:var(--caps)}
.years{display:flex;gap:6px;overflow-x:auto;scrollbar-width:none;padding:2px 13px}
.years::-webkit-scrollbar{display:none}
.ychip{flex-shrink:0;min-width:40px;height:40px;padding:0 10px;border-radius:999px;border:2px solid var(--line);background:var(--paper);display:inline-flex;align-items:center;justify-content:center;gap:1px;text-decoration:none;font-weight:700;font-size:14px;font-variant-numeric:tabular-nums}
.ychip small{font-size:10px;color:var(--muted);font-weight:600}
.ychip.on{background:var(--ink);color:var(--onink);border-color:var(--ink)}
.ychip.on small{color:inherit}
.ychip.uk.on{box-shadow:0 0 0 3px var(--uk) inset}.ychip.us.on{box-shadow:0 0 0 3px var(--us) inset}.ychip.caps.on{box-shadow:0 0 0 3px var(--caps) inset}
.subjchips .fchip{padding-left:4px}
.strand{margin:21px 8px 0;--h:214}
.strand h2{font-size:16px;margin:0 5px 10px;display:flex;align-items:center;gap:10px}
.strand h2 span{display:flex;flex-direction:column;line-height:1.2;min-width:0}
.strand h2 small{font-size:12px;color:var(--muted);font-weight:400}
.strand h2 em{margin-left:auto;font-style:normal;font-size:11px;font-weight:700;color:hsl(var(--h) 60% 30%);background:hsl(var(--h) 80% 90%);border-radius:999px;padding:3px 9px}
:root[data-theme=dark] .strand h2 em{color:hsl(var(--h) 80% 80%);background:hsl(var(--h) 35% 22%)}
.tgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(156px,1fr));gap:8px}
@media (min-width:760px){.tgrid{grid-template-columns:repeat(auto-fill,minmax(200px,1fr))}}
.tcard{--h:inherit;background:linear-gradient(160deg,hsl(var(--h) 85% 93%),var(--paper) 62%);border:2px solid hsl(var(--h) 45% 80%);border-radius:var(--r2);corner-shape:squircle;padding:13px;text-decoration:none;display:flex;flex-direction:column;gap:6px;min-height:150px;transition:transform .15s,border-color .15s}
:root[data-theme=dark] .tcard{background:linear-gradient(160deg,hsl(var(--h) 35% 18%),var(--paper) 62%);border-color:hsl(var(--h) 30% 28%)}
.tcard:hover{transform:translateY(-2px);border-color:hsl(var(--h) 60% 60%)}
.tct{display:flex;align-items:flex-start;justify-content:space-between;gap:6px;margin-bottom:2px}
.tct .yr{font-size:11px;font-weight:700;color:var(--muted);font-variant-numeric:tabular-nums}
.tcard b{font-size:15px;line-height:1.25}
.tcard .sm{font-size:12px;color:var(--muted);line-height:1.4;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.tcard .tmeta{margin-top:auto;display:flex;gap:4px;flex-wrap:wrap}
.tcard .tmeta em{font-style:normal;font-size:10px;font-weight:700;padding:3px 7px;border-radius:999px;background:color-mix(in srgb,var(--paper) 70%,transparent);border:1px solid var(--line)}
.tcard .tmeta em.l{background:hsl(var(--h) 80% 88%);border-color:transparent;color:hsl(var(--h) 60% 25%)}
:root[data-theme=dark] .tcard .tmeta em.l{background:hsl(var(--h) 35% 26%);color:hsl(var(--h) 80% 85%)}
.lesson{padding:0 8px 34px;display:flex;flex-direction:column;gap:13px}
.lesson .card h2{margin:0;font-size:18px;letter-spacing:-.01em}
.lesson p{margin:0;line-height:1.55;font-size:15px}
.facts{margin:0;padding-left:21px;display:flex;flex-direction:column;gap:6px;line-height:1.5}
.diagram{border-radius:16px;corner-shape:squircle;overflow:hidden;border:2px solid var(--line);background:var(--board);aspect-ratio:16/9;position:relative}
.diagram canvas{width:100%;height:100%;display:block}
.methods{display:flex;gap:6px;flex-wrap:wrap}
.mstep{display:flex;gap:10px;align-items:flex-start;padding:8px 0;border-top:1px dashed var(--line);line-height:1.5}
.mstep:first-child{border-top:0}
.mstep .n{width:24px;height:24px;border-radius:999px;background:var(--ink);color:var(--onink);font-size:12px;font-weight:700;display:flex;align-items:center;justify-content:center;flex-shrink:0;margin-top:1px}
.mstep .m{font-family:var(--math);font-size:21px;margin-top:2px}
.pq{font-size:19px;line-height:1.5;font-weight:500}
.pq code{font-family:var(--math);font-size:1.25em;font-weight:400;background:none}
.feedback{border-radius:var(--r1);corner-shape:squircle;padding:13px;font-size:14px;line-height:1.5}
.feedback.good{background:color-mix(in srgb,var(--ok) 30%,var(--paper));border:2px solid var(--ok)}
.feedback.badf{background:color-mix(in srgb,var(--bad) 22%,var(--paper));border:2px solid var(--bad)}
.statrow{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;text-align:center}
.statrow div{background:var(--board);border-radius:var(--r1);padding:8px}
.statrow b{display:block;font-size:20px}
.statrow span{font-size:11px;color:var(--muted)}
.progressbar{height:8px;border-radius:4px;background:var(--soft);overflow:hidden}
.progressbar b{display:block;height:100%;background:var(--ok)}

/* ---------- tables (classes) ---------- */
.tablewrap{overflow-x:auto;border:2px solid var(--line);border-radius:var(--r2);background:var(--paper)}
table.t{border-collapse:collapse;width:100%;font-size:13px}
table.t th,table.t td{padding:10px 12px;text-align:left;border-bottom:1px solid var(--line);white-space:nowrap}
table.t th{font-size:11px;color:var(--muted);font-weight:700;background:var(--board);position:sticky;top:0}
table.t td.num{text-align:right;font-variant-numeric:tabular-nums}
.dotok{display:inline-block;width:10px;height:10px;border-radius:999px;background:var(--ok)}
.dotbad{display:inline-block;width:10px;height:10px;border-radius:999px;background:var(--bad)}
.codebox{font-family:ui-monospace,Menlo,monospace;font-size:22px;letter-spacing:.15em;font-weight:700;padding:8px 13px;border-radius:var(--r1);background:var(--board);border:2px dashed var(--line);display:inline-block}

/* ---------- menus, sheets, toasts ---------- */
.amenuwrap{position:fixed;inset:0;z-index:150}
.amenu{position:absolute;width:236px;background:var(--paper);border:2px solid var(--line);border-radius:18px;corner-shape:squircle;padding:6px;box-shadow:0 12px 30px var(--shadow);display:flex;flex-direction:column}
.amenu button,.amenu a{height:44px;border:0;border-radius:12px;background:transparent;justify-content:flex-start;gap:10px;padding:0 10px;font-size:14px;font-weight:500;width:100%;text-decoration:none;display:flex;align-items:center}
.amenu button:hover,.amenu a:hover{background:var(--soft)}
.amenu hr{border:0;height:2px;background:var(--line);margin:4px 6px}
.amenu .warn{color:var(--badText)}
.sheetwrap{position:fixed;inset:0;z-index:160;background:var(--scrim);display:flex;align-items:flex-end;justify-content:center}
@media (min-width:760px){.sheetwrap{align-items:center}}
.sheet2{background:var(--paper);width:100%;max-width:480px;max-height:88dvh;overflow:auto;border-radius:var(--r3) var(--r3) 0 0;padding:21px 21px calc(21px + env(safe-area-inset-bottom,0px));display:flex;flex-direction:column;gap:13px;animation:up .22s ease-out}
@media (min-width:760px){.sheet2{border-radius:var(--r3)}}
.sheet2 h2{margin:0;font-size:20px;letter-spacing:-.02em}
@keyframes up{from{transform:translateY(30px);opacity:0}}
.apptoast{position:fixed;left:50%;bottom:calc(var(--tabbar) + 21px + env(safe-area-inset-bottom,0px));transform:translate(-50%,10px);z-index:400;background:var(--ink);color:var(--onink);padding:10px 16px;border-radius:999px;font-size:13px;opacity:0;transition:opacity .25s,transform .25s;pointer-events:none;max-width:calc(100vw - 32px);text-align:center}
.apptoast.on{opacity:1;transform:translate(-50%,0)}
.banner-note{margin:0 8px;padding:10px 13px;border-radius:var(--r1);background:color-mix(in srgb,var(--q) 40%,var(--paper));border:2px solid var(--q);font-size:13px;line-height:1.45;display:flex;gap:10px;align-items:center}
.banner-note .btn{margin-left:auto}
.spinner{width:28px;height:28px;border-radius:999px;border:3px solid var(--line);border-top-color:var(--ink);animation:spin .8s linear infinite;margin:34px auto}
@keyframes spin{to{transform:rotate(360deg)}}
.notif{display:flex;gap:10px;align-items:flex-start;padding:13px;border-radius:var(--r2);text-decoration:none;color:inherit;background:var(--paper);border:2px solid var(--line)}
.notif.unread{border-color:var(--ink)}
.notif .tx{flex:1;font-size:14px;line-height:1.45}
.notif .tx span{display:block;font-size:12px;color:var(--muted)}
.foot{font-size:12px;color:var(--muted);line-height:1.6;padding:13px 5px}
.foot a{color:var(--muted)}

/* post page inside the app */
.postview{height:100dvh;position:relative}
@media (min-width:760px){.postview{height:100dvh;border-left:2px solid var(--line);border-right:2px solid var(--line);background:color-mix(in srgb,var(--desk) 60%,transparent)}}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important}}

.listrow.card,.card.hrow{flex-direction:row;align-items:center}
@media (min-width:760px){.main.mfull{max-width:760px}}
.lesson{max-width:880px;width:100%;margin:0 auto}
.lesson .diagram{max-height:380px;aspect-ratio:auto;height:min(380px,50vw)}

/* ---------- settings ---------- */
.setwrap{display:flex;flex-direction:column;gap:13px;padding:0 8px 34px;max-width:640px;width:100%;margin:0 auto}
.sh{margin:0;font-size:16px;display:flex;align-items:center;gap:8px;letter-spacing:-.01em}
.sh svg{color:var(--muted)}
.seg3{display:grid;grid-template-columns:repeat(3,1fr);gap:6px}
.seg3 .opt2{display:flex;flex-direction:column;gap:5px;align-items:center;justify-content:center;font-size:12px}
.seg3 .opt2 svg{display:block}
.banrow{height:52px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background-color:var(--soft);justify-content:flex-start;padding:0 8px}
.banrow span{background:var(--paper);border-radius:999px;padding:4px 10px;font-size:12px;font-weight:600}
.curpick{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:6px}
.curopt{min-height:56px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--field);justify-content:flex-start;gap:8px;padding:8px 10px;text-align:left}
.curopt span{display:flex;flex-direction:column;gap:2px;min-width:0}
.curopt b{font-size:14px}
.curopt small{font-size:10px;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.curopt .curdot{width:14px;height:14px;flex-shrink:0}
.curopt[aria-pressed=true]{border-color:var(--yc);background:color-mix(in srgb,var(--yc) 14%,var(--paper))}
.curopt[aria-pressed=true] .curdot{background:var(--yc)}
.curopt.uk{--yc:var(--uk)}.curopt.us{--yc:var(--us)}.curopt.caps{--yc:var(--caps)}
@media (max-width:420px){.curpick{grid-template-columns:1fr}}
.subjpick{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:6px}
.subjopt{height:52px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--field);justify-content:flex-start;gap:10px;padding:0 10px;position:relative}
.subjopt .tick{margin-left:auto;width:22px;height:22px;border-radius:999px;border:2px solid var(--line);display:flex;align-items:center;justify-content:center;color:transparent}
.subjopt[aria-pressed=true]{border-color:var(--ink)}
.subjopt[aria-pressed=true] .tick{background:var(--ink);border-color:var(--ink);color:var(--onink)}
.topicpick{border:2px solid var(--line);border-radius:var(--r1);corner-shape:squircle;background:var(--field)}
.topicpick summary{list-style:none;display:flex;align-items:center;gap:8px;padding:10px;cursor:pointer}
.topicpick summary::-webkit-details-marker{display:none}
.topicpick summary .muted{margin-left:auto}
.topicpick summary>svg{transition:transform .2s}
.topicpick[open] summary>svg{transform:rotate(90deg)}
.tpsec{padding:0 10px 10px}
.tphead{display:flex;align-items:center;gap:8px;font-size:13px;margin:4px 0 6px}
.tpchips{display:flex;flex-wrap:wrap;gap:5px}
.tpchip{height:32px;border-radius:999px;border:2px solid var(--line);background:var(--paper);padding:0 10px 0 3px;font-size:12px;font-weight:500;gap:6px}
.tpchip .tsym.sm{border-radius:999px}
.tpchip[aria-pressed=true]{border-color:var(--ink);background:var(--ink);color:var(--onink);font-weight:600}

/* ---------- ask ---------- */
.askcard{gap:10px}
.asktitle{height:auto;min-height:48px;padding:11px 13px;line-height:1.35;font-size:17px;font-weight:500;resize:none;overflow:hidden}
.askrow{display:flex;align-items:center;gap:8px;min-width:0}
.askrow>.label{width:44px;flex-shrink:0;font-size:12px;color:var(--muted)}
.askrow .chips{flex:1;min-width:0}
.askrow .tpchip{flex-shrink:0}
.curmini{display:flex;gap:4px;background:var(--soft);border-radius:999px;padding:3px;flex-shrink:0}
.curmini button{height:30px;padding:0 9px;border-radius:999px;font-size:12px;font-weight:600;gap:5px}
.curmini button[aria-pressed=true]{background:var(--paper);box-shadow:0 1px 3px var(--shadow)}
.curmini .curdot{width:9px;height:9px;border-width:2px}
.curmini button[aria-pressed=true] .curdot{background:var(--yc)}
.select.small{height:36px;font-size:13px;width:auto;flex:1;min-width:0;padding-left:10px}
.askmore{border-top:2px dashed var(--line);padding-top:8px;display:flex;flex-direction:column;gap:8px}
.askmore[open]{gap:8px}
.askmore summary{list-style:none;cursor:pointer;display:flex;align-items:center;gap:6px;font-size:13px;font-weight:600}
.askmore summary::-webkit-details-marker{display:none}
.askmore summary .muted{font-weight:400;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.askmore>*:not(summary){margin-top:8px}
.pc.wm{background-color:var(--paper);background-image:linear-gradient(100deg,var(--paper) 55%,color-mix(in srgb,var(--paper) 74%,transparent) 100%),var(--wm);background-size:auto,var(--wms);background-repeat:no-repeat,repeat}

/* ---------- topic page ---------- */
.thero{display:flex;align-items:center;gap:13px;padding:0 13px 10px}
.thero p{margin:0;color:var(--muted);font-size:14px;line-height:1.45}
.modetabs{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:6px;padding:0 8px 13px;position:sticky;top:62px;z-index:15;background:linear-gradient(var(--desk) 70%,transparent)}
@media (min-width:760px){.modetabs{top:72px}}
.modetabs button{height:56px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--paper);flex-direction:column;gap:4px;font-size:12px;font-weight:600;color:var(--muted)}
.modetabs button svg{display:block}
.modetabs button[aria-selected=true]{background:hsl(var(--h) 80% 92%);border-color:hsl(var(--h) 60% 55%);color:hsl(var(--h) 70% 22%)}
:root[data-theme=dark] .modetabs button[aria-selected=true]{background:hsl(var(--h) 35% 22%);border-color:hsl(var(--h) 50% 50%);color:hsl(var(--h) 80% 85%)}
@media (min-width:600px){.modetabs button{flex-direction:row;height:48px;font-size:14px;gap:8px}}
.lesson .lead{font-size:16px;line-height:1.55;margin:0}
.keyfacts{background:hsl(var(--h) 80% 95%);border-radius:var(--r1);corner-shape:squircle;padding:10px 13px;display:flex;flex-direction:column;gap:5px}
:root[data-theme=dark] .keyfacts{background:hsl(var(--h) 30% 16%)}
.keyfacts .facts{gap:4px;font-size:14px}
.lsec{font-size:16px;margin:13px 5px 0;letter-spacing:-.01em;display:flex;align-items:center;gap:8px}
.lsechead{display:flex;align-items:center;gap:8px;flex-wrap:wrap;justify-content:space-between}
.lsechead .lsec{margin-bottom:0}
.levels{display:inline-flex;gap:3px;background:var(--soft);border-radius:999px;padding:3px}
.lvl{height:32px;padding:0 13px;border-radius:999px;font-size:13px;font-weight:600;color:var(--muted)}
.lvl[aria-selected=true]{background:var(--paper);color:var(--ink);box-shadow:0 1px 3px var(--shadow)}
.lvl.l1[aria-selected=true]{box-shadow:inset 0 -3px 0 var(--ok)}.lvl.l2[aria-selected=true]{box-shadow:inset 0 -3px 0 var(--q)}.lvl.l3[aria-selected=true]{box-shadow:inset 0 -3px 0 var(--bad)}
.streak{font-size:13px;font-weight:700}
.excard{gap:10px}
.exhead{display:flex;align-items:center;gap:6px;flex-wrap:wrap;min-height:24px}
.extag{font-size:11px;font-weight:700;padding:4px 9px;border-radius:999px;background:hsl(var(--h,214) 80% 88%);color:hsl(var(--h,214) 70% 22%)}
:root[data-theme=dark] .extag{background:hsl(var(--h,214) 35% 26%);color:hsl(var(--h,214) 80% 88%)}
.kindtag{font-size:11px;font-weight:600;padding:3px 8px;border-radius:999px;border:1.5px solid var(--line);color:var(--muted)}
.kindtag:empty{display:none}
.methwrap{display:flex;flex-direction:column;gap:5px}
.methods{display:flex;gap:6px;flex-wrap:wrap}
.mchip{height:34px;padding:0 13px;border-radius:999px;border:2px solid var(--line);background:var(--field);font-size:13px;font-weight:600;gap:6px}
.mchip.on{background:var(--ink);border-color:var(--ink);color:var(--onink)}
.mchip.comm{border-style:dashed;color:var(--muted)}
.xsteps{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:6px}
.xsteps li{padding:8px 10px 8px 14px;border-radius:12px;border-left:4px solid var(--line);background:var(--field);cursor:pointer;line-height:1.5;font-size:15px}
.xsteps li.now{border-left-color:hsl(var(--h,214) 70% 50%);background:hsl(var(--h,214) 80% 95%)}
:root[data-theme=dark] .xsteps li.now{background:hsl(var(--h,214) 30% 18%)}
.xsteps .m,.tsteps .m{font-family:var(--math);font-size:21px;margin-top:2px}
.tk{font-weight:700}
.m .tk{font-weight:400;text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:3px}
.cta{flex-direction:row;align-items:center;gap:13px;flex-wrap:wrap}
.cta .grow{display:flex;flex-direction:column;gap:3px;min-width:180px}
.deck{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:8px}
.deckcard{flex-direction:column;align-items:flex-start;justify-content:flex-start;gap:6px;text-align:left;padding:12px;border-radius:var(--r2);corner-shape:squircle;border:2px solid var(--line);background:var(--paper);min-height:120px;line-height:1.4}
.deckcard:hover{border-color:hsl(var(--h,214) 60% 55%)}
.deckcard .dq{font-size:14px;font-weight:500;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.deckcard .dm{font-size:11px;color:var(--muted);margin-top:auto}
.deckcard>span:first-child{display:inline-flex}
/* full-screen teaching */
.teach{position:fixed;inset:0;z-index:300;background:var(--board);display:flex;flex-direction:column;padding:calc(13px + env(safe-area-inset-top,0px)) max(13px,3vw) calc(13px + env(safe-area-inset-bottom,0px));gap:13px}
.teach .ttop{display:flex;align-items:center;gap:8px}
.teach .tcount{font-size:13px;font-variant-numeric:tabular-nums}
.teach .tq{font-size:clamp(20px,3vw,40px);font-weight:600;letter-spacing:-.02em;line-height:1.3}
.teach .tq .mathtext{font-size:1.15em}
.teach .tbody{flex:1;display:grid;grid-template-columns:1fr;grid-template-rows:minmax(160px,1fr) auto;gap:13px;min-height:0}
.teach .tbody.nodiag{grid-template-rows:1fr}
@media (min-width:900px) and (min-aspect-ratio:4/3){.teach .tbody{grid-template-columns:1.25fr 1fr;grid-template-rows:1fr}}
.teach .diagram{aspect-ratio:auto;min-height:0;height:100%;max-height:none;background:var(--canvas)}
.teach .tsteps{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:10px;font-size:clamp(17px,2.2vw,28px);overflow:auto;max-height:42vh}
@media (min-width:900px) and (min-aspect-ratio:4/3){.teach .tsteps{max-height:none}}
.teach .tsteps li{padding:10px 14px;border-left:5px solid var(--line);border-radius:12px;background:var(--paper);line-height:1.45}
.teach .tsteps li.past{opacity:.6}
.teach .tsteps li.now{border-left-color:hsl(var(--h,214) 70% 50%)}
.teach .tsteps .m{font-size:1.3em}
.teach .tbar{display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.teach .tbar .methods{flex-wrap:nowrap;overflow-x:auto;max-width:100%;scrollbar-width:none}
@media (max-width:600px){.teach .tbar .label{display:none}.teach .tbar .grow{display:none}.teach .tbar .btn{flex:1}}

/* ---------- whiteboards ---------- */
.bwrap{display:flex;flex-direction:column;gap:13px;padding:0 8px 34px}
.bintro{display:flex;align-items:center;gap:13px;flex-wrap:wrap;background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;padding:13px}
.bintro .grow{display:flex;flex-direction:column;gap:3px;min-width:200px}
.bgridl{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:10px}
@media (min-width:760px){.bgridl{grid-template-columns:repeat(auto-fill,minmax(220px,1fr))}}
.bcard{position:relative;display:flex;flex-direction:column;border-radius:var(--r2);corner-shape:squircle;border:2px solid var(--line);background:var(--paper);overflow:hidden;text-decoration:none;transition:transform .15s}
.bcard:hover{transform:translateY(-2px)}
.bthumb{aspect-ratio:16/10;background:var(--canvas);display:flex;align-items:center;justify-content:center;border-bottom:2px solid var(--line)}
.bthumb img{width:100%;height:100%;object-fit:cover;display:block}
.bempty2{color:var(--faint)}
.bmeta{display:flex;flex-direction:column;gap:2px;padding:8px 40px 10px 10px;min-width:0}
.bmeta .bt{display:flex;align-items:center;gap:6px;min-width:0}
.bmeta b{font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.bcard .dots{position:absolute;right:6px;bottom:10px}
.boardview{height:100dvh}
.boardview .phone.pv{height:100dvh}
.boardview .fulltop{right:70px}
.boardview .ftitle{max-width:min(38vw,260px);overflow:hidden;text-overflow:ellipsis;display:inline-block;line-height:40px}
.boardview .fsaved{font-weight:500;color:var(--muted);border-style:dashed}
.boardview .fsaved:empty{display:none}
@media (max-width:520px){.boardview .fsaved{display:none}.boardview #zoom{display:none}}
.bq{position:absolute;left:13px;top:calc(68px + env(safe-area-inset-top,0px));z-index:3;width:min(360px,calc(100% - 26px));background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;box-shadow:0 8px 21px var(--shadow);overflow:hidden}
.bqhead{width:100%;justify-content:space-between;height:36px;padding:0 12px;font-size:13px;background:hsl(54 95% 88%);color:#1F2328}
.bqhead span{font-weight:500;font-size:12px}
.bqbody{padding:10px 12px;display:flex;flex-direction:column;gap:4px;max-height:30vh;overflow:auto}
.bq.min .bqbody{display:none}

/* ---------- classes ---------- */
.cwrap{padding:0 8px 34px}
.cbadge{--h:214;display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;border-radius:12px;corner-shape:squircle;background:hsl(var(--h) 75% 52%);color:#fff;font-weight:700;letter-spacing:-.02em;line-height:1;white-space:nowrap}
:root[data-theme=dark] .cbadge{background:hsl(var(--h) 55% 42%)}
.cbadge.md{width:36px;height:36px;font-size:13px}
.cbadge.lg{width:46px;height:46px;font-size:16px;border-radius:14px}
.cbadge.xl{width:60px;height:60px;font-size:21px;border-radius:18px}
.codecard{background:linear-gradient(120deg,color-mix(in srgb,var(--q) 30%,var(--paper)),var(--paper) 70%)}
.codebox{font-family:ui-monospace,Menlo,monospace;font-size:20px;letter-spacing:.14em;font-weight:700;padding:8px 13px;border-radius:var(--r1);background:var(--board);border:2px dashed var(--line);display:inline-block;color:var(--ink)}
button.codebox{cursor:copy}
.cgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:8px}
.ccard{display:flex;align-items:center;gap:12px;padding:12px;border-radius:var(--r2);corner-shape:squircle;border:2px solid var(--line);background:linear-gradient(110deg,hsl(var(--h) 80% 93%),var(--paper) 55%);text-decoration:none;color:inherit;width:100%}
:root[data-theme=dark] .ccard{background:linear-gradient(110deg,hsl(var(--h) 30% 18%),var(--paper) 55%)}
.ccard.gen{border-style:dashed}
.ccard .ct{display:flex;flex-direction:column;gap:2px;flex:1;min-width:0}
.ccard .ct b{font-size:15px}
.ccard .ct span{font-size:12px;color:var(--muted)}
.ccard>svg{color:var(--muted);flex-shrink:0}
.awork{flex-direction:row;align-items:center;gap:6px;padding:10px}
.awl{display:flex;align-items:center;gap:10px;flex:1;min-width:0;text-decoration:none;color:inherit}
.awl .t{display:flex;flex-direction:column;gap:3px;flex:1;min-width:0}
.awl .t span{font-size:12px;color:var(--muted)}
.awl .progressbar{height:6px}
.chead{gap:13px}
.chead b{font-weight:500;font-size:14px;line-height:1.4}
.asgrow{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:8px}
.asgcard{display:flex;align-items:flex-start;gap:10px;padding:10px;border-radius:var(--r1);corner-shape:squircle;border:2px solid var(--line);background:var(--paper)}
.asgcard .t{display:flex;flex-direction:column;gap:2px;flex:1;min-width:0}
.asgcard .t span{font-size:12px;color:var(--muted)}
.asgcard .dots{margin-left:0;flex-shrink:0}
/* compact student cards, stacked */
.scards{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:8px}
.scard{background:var(--paper);border:2px solid var(--line);border-radius:var(--r2);corner-shape:squircle;padding:10px;display:flex;flex-direction:column;gap:8px}
.sch{display:flex;align-items:center;gap:10px}
.sch .grow{display:flex;flex-direction:column;min-width:0}
.sch b{font-size:14px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.sch .dots{margin-left:0}
.sstats{display:flex;gap:6px;flex-wrap:wrap}
.sstats span{display:inline-flex;align-items:center;gap:4px;height:26px;padding:0 9px;border-radius:999px;background:var(--soft);font-size:12px;color:var(--muted)}
.sstats b{color:var(--ink)}
.sstats .good{background:color-mix(in srgb,var(--ok) 35%,var(--paper))}
.sstats .low{background:color-mix(in srgb,var(--bad) 28%,var(--paper))}
.sasg{display:flex;gap:5px;flex-wrap:wrap}
.sa{display:inline-flex;align-items:center;gap:4px;height:28px;padding:0 8px 0 3px;border-radius:999px;font-size:12px;font-weight:700;border:2px solid var(--line);font-variant-numeric:tabular-nums}
.sa .tsym.sm{border-radius:999px;height:20px;min-width:20px;font-size:11px}
.sa.done{background:color-mix(in srgb,var(--ok) 40%,var(--paper));border-color:transparent;color:#1F2328}
.sa.part{background:color-mix(in srgb,var(--q) 40%,var(--paper));border-color:transparent;color:#1F2328}
.sa.none{color:var(--faint)}
.stopics{display:flex;gap:4px;flex-wrap:wrap}
.huepick{display:flex;gap:8px;flex-wrap:wrap}
.hue{width:34px;height:34px;border-radius:11px;background:hsl(var(--h) 75% 52%);border:2px solid transparent}
.hue[aria-pressed=true]{box-shadow:0 0 0 2px var(--paper),0 0 0 4px var(--ink)}
.symopt{width:38px;height:38px;border-radius:10px;border:2px solid var(--line);background:var(--field);font-family:var(--math);font-size:17px}
.sheet2.sheetwide{max-width:860px}
.setp{display:grid;grid-template-columns:1fr;gap:13px}
@media (min-width:760px){.setp{grid-template-columns:1fr 1fr}.setlist{max-height:60dvh;overflow:auto;padding-right:4px}}
.setlist,.setprev{display:flex;flex-direction:column;gap:8px;min-width:0}
.previewbox{border:2px dashed var(--line);border-radius:var(--r2);padding:12px;display:flex;flex-direction:column;gap:8px;background:var(--field)}
#pq{display:flex;flex-direction:column;gap:8px}
#pq .diagram{aspect-ratio:auto;max-height:180px}
.fakeinput{height:44px;border-radius:var(--r1);border:2px solid var(--line);background:var(--paper);display:flex;align-items:center;padding:0 12px;color:var(--faint);font-size:14px;justify-content:space-between}
.fakeinput span{font-family:var(--math);color:var(--ink)}
.input::placeholder{text-transform:none;letter-spacing:normal}
.stopics{align-items:center}
.setlist>*,.setprev>*{flex-shrink:0}
.mw{font-family:var(--sans);font-style:normal;font-size:.72em;font-weight:500;margin:0 .12em;letter-spacing:0}
.fchip.sb{padding-left:4px}
.fchip .ssym.sm{width:24px;height:24px;border-radius:999px}
.teach .tbody.nodiag{grid-template-columns:1fr!important;grid-template-rows:1fr!important}
.teach .tbody.nodiag .tsteps{max-width:960px;font-size:clamp(19px,2.6vw,34px);max-height:none}
.askrow .select.small{min-width:92px}
@media (max-width:360px){.askrow>.label{width:auto}.curmini button{padding:0 7px}.askmore summary .muted{display:none}}