/* Learning-guide pages (generated by tools/build-learn.js). Same palette and fonts as app.css. */
:root{--bg:#f5f7fa;--surface:#fff;--border:#dce1e8;--text:#2C3E50;--text-2:#4a5568;--text-m:#8b90a0;--ac:#1B4F8A;--ac-h:#1A2E45;--ac-s:#EEF5FB;--rust:#C0522A;--rust-s:#FDF0EB;--ok:#0E7C66;--ok-s:#E6F4F1;--dc:#1B4F8A;--dt:#EEF5FB;--sh:0 1px 3px rgba(26,46,69,.06);--sh-m:0 4px 14px rgba(26,46,69,.1);--r:10px}
*{margin:0;padding:0;box-sizing:border-box}
body{font-family:'Inter',-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.65;-webkit-font-smoothing:antialiased}
a{color:var(--ac)}a:hover{color:var(--ac-h)}
html:not(.js) .js-only{display:none!important}

.lhdr{position:sticky;top:0;z-index:20;background:linear-gradient(135deg,#1B4F8A,#1A2E45);color:#fff;box-shadow:0 4px 20px rgba(27,79,138,.3)}
.lhdr-in{max-width:1200px;margin:0 auto;padding:.9rem 16px;display:flex;align-items:center;justify-content:space-between;gap:1rem;flex-wrap:wrap}
.brand{color:#fff;font-weight:800;letter-spacing:-.02em;text-decoration:none;font-size:1.05rem}.brand:hover{color:#fff;opacity:.9}
.top{display:flex;gap:1.1rem;align-items:center}.top a{color:#fff;opacity:.8;font-size:.82rem;font-weight:600;text-decoration:none}.top a:hover{color:#fff;opacity:1;text-decoration:underline}

.wrap{max-width:1200px;margin:0 auto;padding:1.75rem 16px 3rem;display:grid;grid-template-columns:280px minmax(0,1fr);gap:2.25rem;align-items:start}
.main{max-width:780px;min-width:0}

/* sidebar */
.side{position:sticky;top:4.5rem;max-height:calc(100vh - 5.5rem);overflow:auto;background:var(--surface);border:1px solid var(--border);border-radius:var(--r);box-shadow:var(--sh);font-size:.82rem}
.side-d>summary{list-style:none;cursor:pointer;padding:.75rem .9rem;font-weight:700;display:flex;justify-content:space-between;gap:.5rem;border-bottom:1px solid var(--border)}
.side-d>summary::-webkit-details-marker{display:none}
.side-d>summary .prog-txt{font-family:'JetBrains Mono',monospace;font-weight:500;color:var(--text-m);font-size:.75rem}
.side-home{display:block;padding:.55rem .9rem;font-weight:600;text-decoration:none;color:var(--text)}
.side-dom{padding:.35rem 0 .5rem;border-top:1px solid var(--border)}
.side-dt{display:flex;gap:.45rem;padding:.4rem .9rem;font-weight:700;color:var(--text);text-decoration:none;line-height:1.35}
.side-dt b{color:var(--dc);font-family:'JetBrains Mono',monospace}
.side ul{list-style:none}
.side li a,.side li .soon{display:flex;gap:.5rem;padding:.3rem .9rem .3rem 1.1rem;color:var(--text-2);text-decoration:none;line-height:1.35;border-left:3px solid transparent}
.side li a:hover{background:var(--ac-s);color:var(--text)}
.side li.cur a{border-left-color:var(--dc);background:var(--dt);color:var(--text);font-weight:600}
.side li .soon{color:var(--text-m)}.side li .soon em{font-style:normal;font-size:.7rem;margin-left:.25rem}
.lid{font-family:'JetBrains Mono',monospace;font-size:.72rem;color:var(--text-m);min-width:1.9rem;padding-top:.1rem}
li.done .lid{color:var(--ok)}li.done .lid::after{content:" \2713"}

/* page furniture */
.crumbs{font-size:.78rem;color:var(--text-m);margin-bottom:1.1rem}.crumbs a{color:var(--text-m)}.crumbs i{font-style:normal;margin:0 .45rem}
.tag{font-family:'JetBrains Mono',monospace;font-size:.72rem;font-weight:500;text-transform:uppercase;letter-spacing:.06em;color:var(--dc);margin-bottom:.4rem}
h1{font-size:2rem;line-height:1.2;font-weight:800;letter-spacing:-.03em;color:var(--ac-h);margin-bottom:.8rem}
.lead{font-size:1.08rem;color:var(--text-2);margin-bottom:1.5rem}
.task{background:var(--dt);border-left:4px solid var(--dc);border-radius:0 var(--r) var(--r) 0;padding:.75rem 1rem;margin-bottom:1.1rem;font-weight:600}
.task span{display:block;font-family:'JetBrains Mono',monospace;font-size:.68rem;font-weight:500;text-transform:uppercase;letter-spacing:.06em;color:var(--dc);margin-bottom:.15rem}

/* lesson body */
.body h2,.sources h2{font-size:1.35rem;font-weight:800;letter-spacing:-.02em;color:var(--ac-h);margin:2.4rem 0 .8rem;padding-top:1.4rem;border-top:1px solid var(--border)}
.body h2:first-child{margin-top:1rem}
.body h3{font-size:1.05rem;font-weight:700;color:var(--ac-h);margin:1.7rem 0 .5rem}
.body p{margin-bottom:1rem}
.body ul,.body ol{margin:0 0 1rem 1.3rem}.body li{margin-bottom:.35rem}
.body code{font-family:'JetBrains Mono',monospace;font-size:.85em;background:var(--ac-s);padding:.1em .35em;border-radius:4px}
.tbl{overflow-x:auto;margin:0 0 1.25rem;border:1px solid var(--border);border-radius:var(--r);background:var(--surface)}
table{border-collapse:collapse;width:100%;font-size:.86rem;line-height:1.45}
th{background:var(--dt);text-align:left;font-weight:700;color:var(--ac-h);padding:.6rem .75rem;border-bottom:1px solid var(--border)}
td{padding:.6rem .75rem;border-top:1px solid var(--border);vertical-align:top}
tbody tr:first-child td{border-top:0}
td:first-child{font-weight:600;color:var(--ac-h)}

/* callouts */
.co{border-radius:var(--r);padding:.9rem 1.1rem;margin:1.25rem 0;border:1px solid;border-left-width:4px}
.co-k{font-family:'JetBrains Mono',monospace;font-size:.68rem;text-transform:uppercase;letter-spacing:.07em;font-weight:500;margin-bottom:.15rem}
.co-t{font-weight:700;margin-bottom:.35rem;color:var(--ac-h)}
.co p:last-child,.co ul:last-child,.co ol:last-child{margin-bottom:0}
.co-trap{background:var(--rust-s);border-color:#efc3ae;border-left-color:var(--rust)}.co-trap .co-k{color:var(--rust)}
.co-rule{background:var(--ac-s);border-color:#c5d9ec;border-left-color:var(--ac)}.co-rule .co-k{color:var(--ac)}
.co-example{background:var(--surface);border-color:var(--border);border-left-color:var(--dc)}.co-example .co-k{color:var(--dc)}

/* sources, done, prev/next */
.btn{display:inline-block;font:inherit;font-size:.85rem;font-weight:700;padding:.6rem 1.1rem;border-radius:8px;border:1.5px solid var(--ac);background:var(--ac);color:#fff;text-decoration:none;cursor:pointer}
.btn:hover{background:var(--ac-h);border-color:var(--ac-h);color:#fff}
.sources ul{margin-left:1.2rem}.sources li{margin-bottom:.3rem}
.done-row{margin:2rem 0 0;display:flex;justify-content:center}
.done-btn.is-done{background:var(--ok-s);border-color:var(--ok);color:var(--ok)}.done-btn.is-done::before{content:"\2713  "}
.pn{display:grid;grid-template-columns:1fr 1fr;gap:1rem;margin:2rem 0}
.pn a{display:block;background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:.8rem 1rem;text-decoration:none;color:var(--ac-h);font-weight:600;font-size:.9rem;line-height:1.35;box-shadow:var(--sh)}
.pn a:hover{border-color:var(--ac);box-shadow:var(--sh-m)}
.pn small{display:block;font-size:.72rem;font-weight:500;color:var(--text-m);margin-bottom:.2rem}
.pn .next{text-align:right;grid-column:2}

/* header practice-tests button, on every page */
.top a.hp{opacity:1;background:#fff;color:var(--ac);padding:.4rem .85rem;border-radius:8px;font-weight:700;display:inline-flex;align-items:center;gap:.4rem;white-space:nowrap}
.top a.hp.is-back::before{content:"\2190"}
.top a.hp:hover{color:var(--ac-h);background:#EEF5FB;text-decoration:none}
.btn-g{background:var(--surface);color:var(--ac)}.btn-g:hover{background:var(--ac-s);color:var(--ac-h)}

/* check questions */
.kc{background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:1rem 1.1rem;margin:0 0 1rem;box-shadow:var(--sh)}
.kc-h{font-family:'JetBrains Mono',monospace;font-size:.68rem;text-transform:uppercase;letter-spacing:.07em;color:var(--dc);margin-bottom:.35rem}
.body .kc-q{font-weight:600;color:var(--ac-h);margin-bottom:.7rem}
.body ul.kc-o{list-style:none;margin:0 0 .8rem;display:grid;gap:.45rem}.body .kc-o li{margin:0}
.kc-o label{display:flex;gap:.6rem;align-items:flex-start;border:1.5px solid var(--border);border-radius:8px;padding:.55rem .75rem;cursor:pointer;font-size:.92rem;line-height:1.45;transition:border-color .12s,background .12s}
.kc-o label:hover{border-color:var(--ac)}
.kc-o input{position:absolute;opacity:0;pointer-events:none}
.kc-l{font-family:'JetBrains Mono',monospace;font-size:.75rem;font-weight:500;min-width:1.4rem;height:1.4rem;border-radius:50%;border:1.5px solid var(--border);display:inline-flex;align-items:center;justify-content:center;flex:none;color:var(--text-2)}
.kc-o input:checked+.kc-l{background:var(--ac);border-color:var(--ac);color:#fff}
.kc-o label:has(input:checked){border-color:var(--ac);background:var(--ac-s)}
.kc-o input:focus-visible+.kc-l{outline:2px solid var(--ac);outline-offset:2px}
.kc.is-done label{cursor:default}
.kc.is-done label.ok{border-color:var(--ok);background:var(--ok-s)}.kc.is-done label.ok .kc-l{background:var(--ok);border-color:var(--ok);color:#fff}
.kc.is-done label.bad{border-color:var(--rust);background:var(--rust-s)}.kc.is-done label.bad .kc-l{background:var(--rust);border-color:var(--rust);color:#fff}
.kc-b[disabled]{opacity:.45;cursor:not-allowed}
.kc-d{margin-top:.6rem;font-size:.9rem}.kc-d summary{cursor:pointer;color:var(--ac);font-weight:600}
.js .kc-d summary{display:none}
.kc-r{margin:.5rem 0 0!important}
.kc-v{font-weight:700;margin-bottom:.25rem}.kc-v.ok{color:var(--ok)}.kc-v.bad{color:var(--rust)}
.kc-again{margin-left:.6rem;font:inherit;font-size:.82rem;background:none;border:0;color:var(--ac);text-decoration:underline;cursor:pointer}

/* "Apply it" exercises */
.ex{background:var(--surface);border:1px solid var(--border);border-top:4px solid var(--dc);border-radius:var(--r);padding:1.1rem 1.2rem;margin:0 0 1rem;box-shadow:var(--sh);scroll-margin-top:5rem}
.ex-h{display:flex;justify-content:space-between;align-items:center;gap:.75rem;flex-wrap:wrap;margin-bottom:.75rem}
.ex-k{font-family:'JetBrains Mono',monospace;font-size:.7rem;text-transform:uppercase;letter-spacing:.06em;color:var(--dc)}
.ex-case{font-size:.8rem;font-weight:700;text-decoration:none;background:var(--dt);color:var(--ac-h);padding:.25rem .65rem;border-radius:99px}
.ex-case:hover{text-decoration:underline;color:var(--ac-h)}
.body .ex>ol{margin-left:0;list-style:none;counter-reset:st;display:grid;gap:.7rem}
.body .ex>ol>li{counter-increment:st;position:relative;padding:.1rem 0 .1rem 2.2rem;margin:0}
.body .ex>ol>li::before{content:counter(st);position:absolute;left:0;top:.1rem;width:1.55rem;height:1.55rem;border-radius:50%;background:var(--dc);color:#fff;font-weight:700;font-size:.8rem;display:flex;align-items:center;justify-content:center}
.body .ex>ol>li em{color:var(--text-2)}
.ex-c{background:var(--bg);border-radius:8px;padding:.75rem .9rem;margin:1rem 0 .75rem}
.ex-ck{font-weight:700;color:var(--ac-h);font-size:.88rem;margin-bottom:.35rem}
.body .ex-c ul{list-style:none;margin:0;display:grid;gap:.3rem}.body .ex-c li{margin:0}
.ex-c label{display:flex;gap:.55rem;align-items:flex-start;font-size:.9rem;cursor:pointer}
.ex-c input{margin-top:.3rem;accent-color:var(--ok);width:1rem;height:1rem;flex:none}
.ex-c input:checked+span{color:var(--text-m);text-decoration:line-through}
.ex-m{border:1px solid var(--border);border-radius:8px;margin-bottom:.75rem}
.ex-m>summary{cursor:pointer;padding:.65rem .9rem;font-weight:700;color:var(--ac);list-style:none}
.ex-m>summary::-webkit-details-marker{display:none}
.ex-m>summary::before{content:"\25B8\00a0\00a0"}.ex-m[open]>summary::before{content:"\25BE\00a0\00a0"}
.ex-mb{padding:.25rem .9rem .5rem;border-top:1px solid var(--border)}
.ex-mb p{margin:.75rem 0}.ex-mb .tbl{margin-top:.5rem}
.ex-copy{font-size:.8rem;padding:.45rem .85rem}
.sources h3.ho{font-size:1rem;font-weight:800;color:var(--ac-h);margin:1.4rem 0 .2rem}
.sources h3.ho span{font-family:'JetBrains Mono',monospace;font-size:.68rem;font-weight:500;text-transform:uppercase;letter-spacing:.05em;color:var(--text-m);margin-left:.4rem}
.ho-p{font-size:.88rem;color:var(--text-2);margin-bottom:.4rem}
.tag-case{color:var(--rust)}

/* curriculum */
.progress{display:flex;align-items:center;gap:.75rem;font-size:.85rem;color:var(--text-2);margin-bottom:1.5rem}
.progress span{font-family:'JetBrains Mono',monospace}
.bar{flex:0 0 180px;height:8px;background:var(--border);border-radius:99px;overflow:hidden}.bar i{display:block;height:100%;width:0;background:var(--ok);transition:width .3s}
.dgrid{display:grid;grid-template-columns:1fr 1fr;gap:1rem}
.dcard{display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--border);border-top:4px solid var(--dc);border-radius:var(--r);padding:1rem 1.1rem;text-decoration:none;color:var(--text);box-shadow:var(--sh);transition:box-shadow .15s,transform .15s}
.dcard:hover{box-shadow:var(--sh-m);transform:translateY(-2px);color:var(--text)}
.dc-top{display:flex;justify-content:space-between;font-family:'JetBrains Mono',monospace;font-size:.7rem;text-transform:uppercase;letter-spacing:.05em}
.dc-n{color:var(--dc);font-weight:500}.dc-w{color:var(--text-m)}
.dcard h2{font-size:1.05rem;font-weight:800;color:var(--ac-h);margin:.35rem 0 .4rem;line-height:1.3}
.dcard p{font-size:.84rem;color:var(--text-2);flex:1}
.dc-foot{display:flex;justify-content:space-between;margin-top:.75rem;font-size:.78rem;font-weight:600;color:var(--text-m)}
.after{margin-top:1.75rem;color:var(--text-2)}

/* domain lesson list */
.llist{list-style:none;display:grid;gap:.6rem}
.llist a,.llist .soon{display:flex;gap:.9rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:.85rem 1rem;text-decoration:none;color:var(--text);box-shadow:var(--sh)}
.llist a:hover{border-color:var(--dc);box-shadow:var(--sh-m)}
.llist .soon{opacity:.6}
.llist .lid{font-size:.85rem;color:var(--dc);min-width:2.2rem}
.llist .lt b{display:block;color:var(--ac-h)}.llist .lt span{display:block;font-size:.85rem;color:var(--text-2);margin-top:.15rem}

.notice{margin-top:2.5rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--r);padding:1rem 1.1rem;font-size:.8rem;color:var(--text-2)}
.notice strong{display:block;color:var(--ac-h);margin-bottom:.25rem}

@media(max-width:900px){
 .wrap{grid-template-columns:minmax(0,1fr);gap:1.25rem;padding-top:1.1rem}
 .side{position:static;max-height:none}
 h1{font-size:1.6rem}
 .dgrid{grid-template-columns:1fr}
}
@media(max-width:560px){
 .pn{grid-template-columns:1fr}.pn .next{grid-column:1}
 .bar{flex-basis:110px}
 .top{gap:.8rem}.top a.tl{display:none}
 .lhdr-in{flex-wrap:nowrap;padding:.65rem 16px}.brand{font-size:.92rem}.top a.hp{font-size:.78rem;padding:.35rem .65rem}
 .side{max-height:none}
}
@media print{.lhdr,.side,.pn,.done-row,.kc-b,.ex-copy{display:none}.wrap{display:block}}