:root{
  --panel:#e8ebe6;
  --panel-deep:#dfe3dd;
  --surface:#ffffff;
  --ink:#182126;
  --muted:#5b6a70;
  --line:#d3d9d2;
  --dial:#1e5f63;
  --dial-soft:#e3efee;
  --good:#2f7d46;
  --bad:#a63a2b;
  --amber:#b07a1e;
  --radius:12px;
  --shadow-1:0 1px 2px rgba(24,33,38,.06),0 2px 8px rgba(24,33,38,.05);
  --shadow-2:0 2px 4px rgba(24,33,38,.08),0 10px 28px rgba(24,33,38,.10);
  --ease:cubic-bezier(.22,.8,.3,1);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;color:var(--ink);
  background:
    radial-gradient(1100px 500px at 85% -10%, #f2f5f0 0%, transparent 60%),
    linear-gradient(var(--panel), var(--panel-deep));
  min-height:100vh;background-attachment:fixed;
  font:400 clamp(15px,1.5vw,16.5px)/1.6 "IBM Plex Sans",system-ui,sans-serif}
main{max-width:780px;margin:0 auto;padding:clamp(1rem,3vw,2rem) 1rem 4rem}
a{color:var(--dial)}
h1,h2,h3{font-family:"IBM Plex Sans Condensed",sans-serif;line-height:1.12;margin:0 0 .5rem;
  letter-spacing:-.01em}
h1{font-size:clamp(1.5rem,4vw,1.9rem)}
h2{font-size:clamp(1.15rem,3vw,1.4rem)}
h3{font-size:1.05rem}
.mono,.timer,.ref,.smeter-read,.pos{font-family:"IBM Plex Mono",monospace}

/* motion foundations */
@media (prefers-reduced-motion:no-preference){
  main > *{animation:rise .45s var(--ease) backwards}
  main > *:nth-child(2){animation-delay:.05s}
  main > *:nth-child(3){animation-delay:.1s}
  main > *:nth-child(4){animation-delay:.15s}
  main > *:nth-child(n+5){animation-delay:.2s}
  @keyframes rise{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:none}}
  @keyframes seg{from{transform:scaleY(0)}to{transform:scaleY(1)}}
  @keyframes pop{0%{transform:scale(.96);opacity:0}100%{transform:scale(1);opacity:1}}
}

/* masthead */
.masthead{display:flex;flex-wrap:wrap;align-items:baseline;gap:.35rem 1rem;
  padding:.85rem clamp(1rem,3vw,1.5rem);
  background:rgba(255,255,255,.82);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.bmc{margin-left:auto;align-self:center;line-height:0;flex:none}
.bmc img{height:34px;width:auto;display:block;border-radius:8px;
  transition:transform .2s var(--ease)}
.bmc:hover img{transform:translateY(-1px)}
.masthead nav + .bmc{margin-left:1rem}
.bmc-login{display:none;text-align:center;margin:1.2rem 0}
.bmc-login img{height:46px;width:auto;border-radius:8px}
.brand{display:inline-flex;align-items:center;gap:.5rem;text-decoration:none}
.brand-mark{height:36px;width:36px;display:block;flex:none}
.brand:hover .plate{transform:translateY(-1px);box-shadow:var(--shadow-1)}
.auth-hero{text-align:center;margin:1.5rem auto .4rem}
.auth-logo{width:min(240px,64%);height:auto;border-radius:18px}
.auth-layout{display:flex;flex-wrap:wrap;gap:1.2rem;align-items:stretch;
  max-width:920px;margin:.5rem auto 2rem}
.auth-info{flex:1 1 300px;margin:0;background:var(--dial-soft);border-color:transparent}
.auth-card{flex:0 1 360px;margin:0}
@media (max-width:640px){.auth-info,.auth-card{flex-basis:100%}}
.auth-info h2{margin-top:0}
.feature-list{list-style:none;margin:.8rem 0;padding:0;font-size:.92rem}
.feature-list li{position:relative;padding:.35rem 0 .35rem 1.5rem}
.feature-list li::before{content:"✓";position:absolute;left:0;color:var(--dial);font-weight:700}
.plate{font-family:"IBM Plex Mono",monospace;font-weight:500;font-size:1.2rem;
  letter-spacing:.08em;color:var(--ink);text-decoration:none;
  border:1.5px solid var(--ink);padding:.08rem .55rem;border-radius:6px;
  transition:transform .2s var(--ease),box-shadow .2s var(--ease)}
.plate:hover{transform:translateY(-1px);box-shadow:var(--shadow-1)}
.plate span{color:var(--dial)}
.strap{font-size:.74rem;color:var(--muted);letter-spacing:.06em;text-transform:uppercase}
.masthead nav{margin-left:auto;font-size:.85rem;display:flex;gap:1rem;align-items:baseline}
.op{color:var(--muted)}
footer{max-width:780px;margin:0 auto;padding:0 1rem 2rem;font-size:.75rem;color:var(--muted)}

/* cards & controls */
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:clamp(1rem,3vw,1.4rem);margin:0 0 1.1rem;box-shadow:var(--shadow-1);
  transition:box-shadow .25s var(--ease)}
.flash{background:#f7edd8;border:1px solid var(--amber);border-radius:var(--radius);
  padding:.65rem 1rem;margin-bottom:1rem;font-size:.9rem;animation:pop .3s var(--ease)}
button,.btn{font:600 .92rem "IBM Plex Sans",sans-serif;color:#fff;background:var(--dial);
  border:none;border-radius:8px;padding:.6rem 1.2rem;cursor:pointer;text-decoration:none;
  display:inline-block;transition:transform .15s var(--ease),box-shadow .15s var(--ease),
  background .15s var(--ease)}
button:hover,.btn:hover{transform:translateY(-1px);box-shadow:var(--shadow-2);background:#1a7076}
button:active,.btn:active{transform:translateY(0) scale(.98)}
button.quiet,.btn.quiet{background:transparent;color:var(--dial);border:1.5px solid var(--dial)}
button.quiet:hover,.btn.quiet:hover{background:var(--dial-soft)}
button.danger{background:var(--bad)}
button.danger:hover{background:#b8462f}
button:focus-visible,a:focus-visible,input:focus-visible{outline:2px solid var(--dial);outline-offset:2px}
input[type=email],input[type=password],input[type=text],textarea{
  width:100%;padding:.6rem .75rem;border:1px solid var(--line);border-radius:8px;
  font:inherit;background:#fff;transition:border-color .15s,box-shadow .15s}
input:focus,textarea:focus{border-color:var(--dial);box-shadow:0 0 0 3px rgba(30,95,99,.12);outline:none}
textarea{min-height:4.5rem}
label{display:block;font-size:.85rem;color:var(--muted);margin:.7rem 0 .25rem}
.ref{font-size:.78rem;color:var(--muted);letter-spacing:.04em}

/* S-meter */
.smeter{display:flex;align-items:center;gap:.7rem;margin:.4rem 0;padding:.15rem 0}
.smeter-label{flex:1;font-size:.9rem;min-width:0}
.smeter-label a{color:var(--ink);text-decoration:none;border-bottom:1px dotted transparent;
  transition:border-color .15s}
.smeter-label a:hover{border-bottom-color:var(--dial)}
.smeter-scale{display:flex;gap:2.5px}
.smeter-scale i{width:11px;height:16px;background:#e0e5df;border-radius:2.5px;
  transform-origin:bottom}
.smeter-scale i.on{background:var(--good)}
.smeter-scale i.on:nth-child(-n+3){background:var(--bad)}
.smeter-scale i.on:nth-child(4),.smeter-scale i.on:nth-child(5),.smeter-scale i.on:nth-child(6){background:var(--amber)}
@media (prefers-reduced-motion:no-preference){
  .smeter-scale i.on{animation:seg .4s var(--ease) backwards}
  .smeter-scale i.on:nth-child(2){animation-delay:.04s}.smeter-scale i.on:nth-child(3){animation-delay:.08s}
  .smeter-scale i.on:nth-child(4){animation-delay:.12s}.smeter-scale i.on:nth-child(5){animation-delay:.16s}
  .smeter-scale i.on:nth-child(6){animation-delay:.2s}.smeter-scale i.on:nth-child(7){animation-delay:.24s}
  .smeter-scale i.on:nth-child(8){animation-delay:.28s}.smeter-scale i.on:nth-child(9){animation-delay:.32s}
}
.smeter-read{font-size:.85rem;width:5rem;text-align:right;color:var(--muted)}

/* questions */
.q-stem{font-weight:500;font-size:1.02rem;margin:.25rem 0 .8rem}
.opt{display:flex;gap:.65rem;align-items:flex-start;border:1.5px solid var(--line);
  border-radius:10px;padding:.65rem .8rem;margin:.45rem 0;cursor:pointer;background:#fff;
  transition:border-color .15s var(--ease),background .15s var(--ease),
  transform .15s var(--ease),box-shadow .15s var(--ease)}
.opt input{margin-top:.3rem;accent-color:var(--dial)}
.opt:hover{border-color:var(--dial);transform:translateX(3px)}
.opt:has(input:checked){border-color:var(--dial);background:var(--dial-soft);
  box-shadow:0 0 0 3px rgba(30,95,99,.10)}
.opt.correct{border-color:var(--good);background:#eef6ef}
.opt.wrong{border-color:var(--bad);background:#f9efec}
div.opt{cursor:default}
div.opt:hover{transform:none}
.verdict{font-family:"IBM Plex Mono",monospace;font-size:.92rem;font-weight:500;margin:.2rem 0 .5rem}
.verdict.good{color:var(--good)}.verdict.bad{color:var(--bad)}
.explain{border-left:3px solid var(--dial);padding:.5rem .9rem;margin:.8rem 0 0;
  font-size:.93rem;background:#f3f7f4;border-radius:0 8px 8px 0;white-space:pre-line;
  animation:pop .35s var(--ease) backwards;animation-delay:.1s}

/* exam chrome */
.exambar{position:sticky;top:3.6rem;z-index:10;display:flex;justify-content:space-between;
  align-items:center;gap:1rem;color:#fff;border-radius:12px;
  background:rgba(24,33,38,.92);backdrop-filter:blur(8px);
  padding:.55rem 1rem;margin-bottom:1rem;box-shadow:var(--shadow-2)}
.progress{flex:1;height:5px;background:rgba(255,255,255,.18);border-radius:99px;overflow:hidden}
.progress b{display:block;height:100%;width:0;background:#7dd3a0;border-radius:99px;
  transition:width .35s var(--ease)}
.timer{font-size:1.05rem;letter-spacing:.06em;font-variant-numeric:tabular-nums}
.timer.low{color:#ffb4a4;animation:blink 1s steps(2,end) infinite}
@keyframes blink{50%{opacity:.55}}
.examq{border-bottom:1px solid var(--line);padding:1rem 0}
.pos{color:var(--muted);font-size:.8rem}

.score-line{font-family:"IBM Plex Mono",monospace;font-size:clamp(1.4rem,4vw,1.8rem);margin:.3rem 0}
.pass{color:var(--good)}.fail{color:var(--bad)}
table{border-collapse:collapse;width:100%;font-size:.9rem}
td,th{text-align:left;padding:.45rem .55rem;border-bottom:1px solid var(--line)}
th{font-size:.76rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted)}
tr{transition:background .12s}
tbody tr:hover,table tr:hover{background:#f5f8f5}
.sess-score{display:flex;justify-content:space-between;align-items:center;gap:1rem;
  padding:.5rem .9rem;font-size:.9rem}
.advice-md > :first-child{margin-top:0}
.advice-md > :last-child{margin-bottom:0}
.advice-md ul,.advice-md ol{margin:.4rem 0 .4rem 1.1rem;padding:0}
.advice-md li{margin:.25rem 0}
.advice-md p{margin:.5rem 0}
.ai-spin{display:inline-flex;align-items:center;gap:.5rem;font-size:.85rem;color:var(--muted)}
.ai-spin[hidden]{display:none}
.spinner{width:1rem;height:1rem;border:2px solid var(--line);border-top-color:var(--dial);
  border-radius:50%;display:inline-block;animation:spin .7s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.row-actions{display:flex;gap:.6rem;flex-wrap:wrap;margin-top:.7rem}
.pillrow{display:flex;gap:.45rem;flex-wrap:wrap;margin:.4rem 0 1rem}
.pill{font-size:.82rem;border:1.5px solid var(--line);border-radius:99px;padding:.28rem .8rem;
  background:#fff;cursor:pointer;display:inline-flex;gap:.4rem;align-items:center;
  transition:border-color .15s,background .15s,transform .15s var(--ease)}
.pill:hover{border-color:var(--dial);transform:translateY(-1px)}
.pill input{accent-color:var(--dial)}
.pill:has(input:checked){border-color:var(--dial);background:var(--dial-soft)}
.checknote{font-size:.82rem;color:var(--bad);font-family:"IBM Plex Mono",monospace;margin:.3rem 0}
/* Truncated syllabus objective: clamp to 2 lines, tap/click to reveal the rest */
.clamp{display:-webkit-box;-webkit-line-clamp:2;line-clamp:2;-webkit-box-orient:vertical;
  overflow:hidden;cursor:pointer}
.clamp.open{-webkit-line-clamp:unset;line-clamp:unset;overflow:visible}
@media (max-width:520px){
  .smeter-scale i{width:8px;height:14px}
  .masthead nav{width:100%;margin-left:0}
  .exambar{top:.5rem}
  .bmc{display:none}         /* header coffee button is cramped on phones... */
  .bmc-login{display:block}  /* ...show it on the login page instead */
}