/* HOW TO // AI — CERT app — navy/gold brand, mobile-first */
:root{
  --navy:#002263; --navy2:#0a3a8c; --gold:#FFB300; --gold-soft:#fff8e6;
  --bg:#f4f6fa; --card:#fff; --line:#e5e7eb; --txt:#111827; --mut:#6b7280;
  --ok:#10b981; --ok-bg:#ecfdf5; --bad:#ef4444; --bad-bg:#fef2f2; --r:12px;
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--txt);font:16px/1.5 "Rubik",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif}
.boot{padding:80px 20px;text-align:center;color:var(--mut)}
a{color:var(--navy2)}
button{font:inherit}

/* layout */
.topbar{background:#fff;color:var(--navy);display:flex;align-items:center;gap:14px;padding:13px 18px;position:sticky;top:0;z-index:50;border-bottom:1px solid var(--line)}
.topbar .logo{display:inline-flex;align-items:center;gap:9px;text-decoration:none;white-space:nowrap}
.topbar .logo-img{height:34px;width:auto;display:block}
.topbar .logo .cmark{color:var(--navy);font-weight:800;font-size:1.08rem;letter-spacing:.1em;padding-left:11px;border-left:2px solid var(--gold)}
.topbar .cert-tag{background:#eef4ff;color:var(--navy);border-radius:99px;padding:3px 12px;font-size:.78rem;font-weight:600;white-space:nowrap}
.topbar .cert-switch{background:#eef4ff;color:var(--navy);border:1px solid #d6e2f7;border-radius:99px;padding:6px 32px 6px 15px;font:600 .9rem/1.2 "Rubik",sans-serif;width:auto;max-width:360px;min-width:0;text-overflow:ellipsis}
@media (max-width:600px){.topbar .cert-switch{max-width:54vw;font-size:.82rem;padding-right:28px}}
.topbar .spacer{flex:1}
.topbar .who{font-size:.82rem;color:var(--mut);max-width:180px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.nav{display:flex;gap:2px;background:#fff;border-bottom:1px solid var(--line);padding:0 10px;overflow-x:auto;position:sticky;top:53px;z-index:40}
.nav a{padding:13px 14px;text-decoration:none;color:var(--mut);font-weight:600;font-size:.9rem;border-bottom:3px solid transparent;white-space:nowrap}
.nav a.on{color:var(--navy);border-bottom-color:var(--gold)}
.wrap{max-width:980px;margin:0 auto;padding:22px 16px 60px}

/* cards & ui atoms */
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:20px;margin-bottom:16px}
.grid{display:grid;gap:14px}
.grid.cols2{grid-template-columns:repeat(auto-fit,minmax(220px,1fr))}
.grid.cols3{grid-template-columns:repeat(auto-fit,minmax(160px,1fr))}
.grid.cols4{grid-template-columns:repeat(auto-fit,minmax(140px,1fr))}
/* practice mode cards: bottom-align the action buttons across each row */
.practice-grid .card{display:flex;flex-direction:column}
.practice-grid .card .btn{margin-top:auto;align-self:flex-start}
h1{font-size:1.5rem;margin:.2em 0 .6em;font-weight:800}
h2{font-size:1.18rem;margin:.2em 0 .6em;font-weight:700}
.mut{color:var(--mut)} .small{font-size:.84rem}
.btn{display:inline-block;background:var(--navy);color:#fff;border:0;border-radius:9px;padding:12px 20px;font-weight:700;cursor:pointer;text-decoration:none;text-align:center}
.btn:hover{background:var(--navy2)}
.btn.gold{background:var(--gold);color:var(--navy)}
.btn.ghost{background:#fff;color:var(--navy);border:1.5px solid var(--line)}
.btn.sm{padding:8px 14px;font-size:.86rem}
.btn[disabled]{opacity:.55;cursor:default}
.pill{display:inline-block;background:#eef4ff;color:var(--navy);font-size:.74rem;font-weight:700;padding:3px 10px;border-radius:99px}
.pill.gold{background:var(--gold-soft);color:#92600a}
/* sign-in / sign-up sales bullets */
.signin-list{list-style:none;padding:0;margin:4px 0 14px}
.signin-list li{position:relative;padding-left:26px;font-size:.92rem;line-height:1.45;margin:0 0 9px}
.signin-list li::before{content:"✓";position:absolute;left:0;top:0;color:var(--ok);font-weight:800}
.signin-list strong{color:var(--navy)}
.lock{opacity:.55}
.msg{font-size:.88rem;margin-top:10px;min-height:1.2em}
.msg.err{color:var(--bad)}
.msg.ok{color:var(--ok)}
input[type=email],input[type=text],input[type=number],select{padding:11px 13px;border:1px solid #d1d5db;border-radius:8px;font:inherit;width:100%}
.statbig{font-size:2rem;font-weight:800;color:var(--navy);line-height:1.1}
.statlbl{font-size:.78rem;color:var(--mut);text-transform:uppercase;letter-spacing:.05em}
.bar{height:8px;background:#eef1f6;border-radius:4px;overflow:hidden}
.bar>span{display:block;height:100%;background:var(--gold);border-radius:4px;transition:width .3s}
.bar.green>span{background:var(--ok)}

/* quiz */
.q-progress{display:flex;justify-content:space-between;align-items:center;font-size:.85rem;color:var(--mut);margin-bottom:10px;gap:10px;flex-wrap:wrap}
.q-timer{font-weight:800;color:var(--navy);font-variant-numeric:tabular-nums}
.q-timer.low{color:var(--bad)}
.q-domain{display:inline-block;background:#eef4ff;color:var(--navy);font-size:.74rem;font-weight:600;padding:3px 10px;border-radius:99px;margin:8px 0 10px}
.q-stem{font-size:1.08rem;font-weight:600;line-height:1.45;margin:0 0 16px}
.q-opt{display:flex;gap:12px;align-items:flex-start;width:100%;text-align:left;background:#f8fafc;border:1.5px solid var(--line);border-radius:10px;padding:13px 15px;margin:0 0 10px;cursor:pointer;font-size:.97rem;line-height:1.4}
.q-opt:hover{border-color:#94a3b8}
.q-opt .k{flex:0 0 auto;font-weight:700;color:var(--navy)}
.q-opt.is-correct{background:var(--ok-bg);border-color:var(--ok)}
.q-opt.is-wrong{background:var(--bad-bg);border-color:var(--bad)}
.q-opt[disabled]{cursor:default}
.q-opt.sel{border-color:var(--navy);background:#eef4ff}
.q-multi-hint{font-size:.82rem;color:var(--navy);font-weight:600;margin:0 0 10px}
.q-rationale{background:#f8fafc;border-left:4px solid var(--gold);border-radius:0 10px 10px 0;padding:13px 15px;margin:12px 0;font-size:.94rem}
.q-actions{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-top:10px}
.q-flag{background:none;border:none;cursor:pointer;font-size:1.25rem;line-height:1;padding:4px}
.score-hero{text-align:center;padding:8px 0}
.score-hero .n{font-size:3rem;font-weight:800;color:var(--navy)}

/* tutor */
.tutor{border-top:1px dashed var(--line);margin-top:14px;padding-top:14px}
.tutor-log{max-height:340px;overflow-y:auto;display:flex;flex-direction:column;gap:8px;position:relative}
.tutor-logwrap{position:relative;margin-bottom:10px}
.tutor-logwrap::after{content:"";position:absolute;left:0;right:0;bottom:0;height:40px;background:linear-gradient(to top,var(--card),rgba(255,255,255,0));pointer-events:none;opacity:0;transition:opacity .15s}
.tutor-logwrap.more::after{opacity:1}
.tutor-more{position:absolute;left:50%;bottom:8px;transform:translateX(-50%);background:var(--navy);color:#fff;font-size:.72rem;font-weight:700;letter-spacing:.03em;padding:3px 11px;border-radius:99px;cursor:pointer;opacity:0;pointer-events:none;transition:opacity .15s;z-index:2}
.tutor-logwrap.more .tutor-more{opacity:.95;pointer-events:auto}
.tutor-m{padding:10px 13px;border-radius:10px;font-size:.92rem;max-width:92%;white-space:pre-wrap}
.tutor-m.user{background:var(--navy);color:#fff;align-self:flex-end}
.tutor-m.ai{background:#f1f5f9;align-self:flex-start}
.tutor-row{display:flex;gap:8px}
.tutor-row input{flex:1}
.tutor-cta{display:flex;align-items:center;gap:10px;flex-wrap:wrap}
.tutor-by{font-size:.74rem;color:var(--mut);font-style:italic}
.tutor-teaser{font-size:.9rem;line-height:1.5;color:#374151;background:var(--gold-soft);border:1px solid #f6dfa3;border-radius:10px;padding:12px 14px}
.tutor-teaser .tutor-by{display:inline-block;margin-left:4px}
.tutor-free{margin:8px 0 0;font-size:.84rem;line-height:1.45;color:#92600a;background:var(--gold-soft);border:1px solid #f6dfa3;border-radius:8px;padding:8px 11px}
.tutor-free a,.tutor-up a{color:#0a3a8c;font-weight:600}
.tutor-up{font-size:.92rem;color:var(--txt)}
/* rendered markdown inside an AI tutor answer */
.tutor-m.ai{white-space:normal}
.tutor-m.ai>:first-child{margin-top:0}
.tutor-m.ai>:last-child{margin-bottom:0}
.tutor-m.ai p{margin:0 0 8px}
.tutor-m.ai h4{margin:11px 0 4px;font-size:.95rem;color:var(--navy)}
.tutor-m.ai h5{margin:9px 0 3px;font-size:.9rem;color:var(--navy)}
.tutor-m.ai ul,.tutor-m.ai ol{margin:4px 0 8px;padding-left:20px}
.tutor-m.ai li{margin:2px 0}
.tutor-m.ai code{background:#e2e8f0;padding:1px 5px;border-radius:4px;font-size:.86em}
.tutor-m.ai strong{color:var(--navy)}
.tutor-m.ai hr{border:0;border-top:1px solid #d7dee8;margin:10px 0}

/* flashcards */
.flash{perspective:1000px;cursor:pointer;min-height:230px}
.flash-inner{position:relative;width:100%;min-height:230px;transition:transform .45s;transform-style:preserve-3d}
.flash.flipped .flash-inner{transform:rotateY(180deg)}
.flash-face{position:absolute;inset:0;backface-visibility:hidden;display:flex;align-items:center;justify-content:center;padding:24px;border-radius:var(--r);border:1px solid var(--line);background:#fff;font-size:1.02rem;text-align:center;overflow-y:auto}
.flash-face.back{transform:rotateY(180deg);background:var(--gold-soft)}

/* study */
.study-tabs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:14px}
.study-tabs button{background:#fff;border:1.5px solid var(--line);border-radius:99px;padding:8px 16px;font-weight:600;cursor:pointer;font-size:.88rem}
.study-tabs button.on{background:var(--navy);color:#fff;border-color:var(--navy)}
table.facts{width:100%;border-collapse:collapse;font-size:.93rem}
table.facts td{padding:8px 10px;border-bottom:1px solid var(--line)}
table.facts td:first-child{font-weight:700;color:var(--navy);width:32%}
.gloss dt{font-weight:700;color:var(--navy);margin-top:12px}
.gloss dd{margin:2px 0 0}

/* cert switcher (topbar, shown once >1 cert is live) */
.cert-switch{background:#eef4ff;color:var(--navy);border:1px solid #d8e4ff;border-radius:99px;padding:4px 10px;font-family:inherit;font-size:.78rem;font-weight:600;cursor:pointer}

/* leaderboard */
table.lb{width:100%;border-collapse:collapse;font-size:.95rem}
table.lb th{text-align:left;color:var(--mut);font-size:.74rem;text-transform:uppercase;letter-spacing:.05em;padding:10px 8px;border-bottom:1px solid var(--line)}
table.lb td{padding:10px 8px;border-bottom:1px solid var(--line)}
table.lb tr:last-child td{border-bottom:0}
table.lb td.rank{width:44px;font-weight:800;color:var(--navy);font-size:1.05rem}
table.lb tr.you td{background:var(--gold-soft)}

/* readiness certificate */
.cert-dot{display:inline-block;width:18px;height:18px;border-radius:50%;background:#eef1f6;border:2px solid var(--line);margin-right:6px;vertical-align:middle}
.cert-dot.on{background:var(--gold);border-color:var(--gold)}

/* modal */
.modal-bg{position:fixed;inset:0;background:rgba(2,10,40,.55);display:flex;align-items:center;justify-content:center;z-index:100;padding:16px}
.modal{background:#fff;border-radius:16px;padding:26px;max-width:520px;width:100%;max-height:92vh;overflow-y:auto}
.modal h2{margin-top:0}
.modal .x{float:right;background:none;border:none;font-size:1.3rem;cursor:pointer;color:var(--mut)}
.price{border:1.5px solid var(--line);border-radius:12px;padding:18px;margin-bottom:12px}
.price.hot{border-color:var(--gold);background:var(--gold-soft)}
.price .amt{font-size:1.7rem;font-weight:800;color:var(--navy)}
.price ul{margin:10px 0;padding-left:20px;font-size:.9rem}

@media (max-width:560px){
  .wrap{padding:16px 10px 50px}
  .card{padding:16px}
  .topbar .who{display:none}
}