/* The Bridge Centre — site styles
   Layout modelled on Khan Academy: navy top bar with Explore + Search,
   calm hero band, catalogue grid, course pages with a unit sidebar. */
:root{
  --navy:#1e3a5f; --navy-deep:#14294a; --gold:#c4a35a; --gold-soft:#efe2bf;
  --teal:#2a6f6f; --teal-soft:#e3efee; --paper:#f7f4ee; --ink:#1c2430;
  --muted:#55606e; --line:#dcd6ca; --card:#ffffff; --link:#1f5aa6;
  --red:#b3261e; --focus:#f2b705;
  --radius:10px; --shadow:0 1px 2px rgba(20,41,74,.08),0 4px 14px rgba(20,41,74,.06);
  --serif:'Bodoni Moda','Libre Bodoni','Times New Roman',serif;
  --sans:'Inter','Helvetica Neue',Arial,sans-serif;
  --max:1180px;
}
*{box-sizing:border-box}
html{font-size:112.5%;-webkit-text-size-adjust:100%} /* 18px base: easier reading */
body{margin:0;font-family:var(--sans);color:var(--ink);background:#fff;line-height:1.6}
img{max-width:100%;height:auto}
a{color:var(--link);text-underline-offset:3px}
a:hover{color:var(--navy)}
:focus-visible{outline:3px solid var(--focus);outline-offset:2px;border-radius:4px}
h1,h2,h3{line-height:1.25;color:var(--navy-deep)}
h1,.display{font-family:var(--serif);font-weight:500}
h1{font-size:2.1rem;margin:.2em 0 .4em}
h2{font-size:1.45rem;margin:1.6em 0 .5em}
h3{font-size:1.15rem;margin:1.3em 0 .4em}
.skip{position:absolute;left:-999px;top:0;background:#fff;padding:.6rem 1rem;z-index:100}
.skip:focus{left:1rem}
.wrap{max-width:var(--max);margin:0 auto;padding:0 16px}
.suit-h,.suit-d{color:var(--red)}

/* ---------- Top bar ---------- */
.topbar{background:var(--navy-deep);color:#fff;position:sticky;top:0;z-index:50}
.topbar .wrap{display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:1rem;min-height:64px}
.tb-left,.tb-right{display:flex;align-items:center;gap:.75rem}
.tb-right{justify-content:flex-end}
.brand{display:flex;align-items:center;gap:.6rem;color:#fff;text-decoration:none}
.brand img{width:40px;height:42px}
.brand span{font-family:var(--serif);font-size:1.2rem;letter-spacing:.06em;white-space:nowrap}
.brand:hover{color:var(--gold-soft)}
.explore-btn{background:none;border:0;color:#fff;font:600 .95rem var(--sans);cursor:pointer;padding:.55rem .4rem;display:flex;align-items:center;gap:.35rem}
.explore-btn::after{content:"";border:5px solid transparent;border-top-color:currentColor;margin-top:5px}
.search{display:flex;align-items:center;border:1px solid rgba(255,255,255,.75);border-radius:6px;padding:0 .6rem;height:40px;min-width:200px}
.search svg{flex:none}
.search input{background:none;border:0;color:#fff;font:1rem var(--sans);padding:.4rem;width:100%}
.search input::placeholder{color:#d7dfea}
.search input:focus{outline:none}
.search:focus-within{outline:3px solid var(--focus)}
.tb-link{color:#fff;text-decoration:none;font-weight:600;font-size:.95rem;padding:.5rem .3rem}
.tb-link:hover{color:var(--gold-soft)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.4rem;font:600 1rem var(--sans);text-decoration:none;border-radius:6px;padding:.65rem 1.1rem;border:2px solid transparent;cursor:pointer;min-height:44px}
.btn-gold{background:var(--gold);color:var(--navy-deep)}
.btn-gold:hover{background:#d5b671;color:var(--navy-deep)}
.btn-navy{background:var(--navy);color:#fff}
.btn-navy:hover{background:var(--navy-deep);color:#fff}
.btn-outline{background:#fff;border-color:var(--navy);color:var(--navy)}
.btn-outline:hover{background:var(--teal-soft)}

/* Explore mega-menu */
.mega{display:none;position:absolute;left:0;right:0;top:100%;background:#fff;color:var(--ink);box-shadow:0 12px 30px rgba(0,0,0,.18);border-top:3px solid var(--gold)}
.mega.open{display:block}
.mega .wrap{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1.5rem;padding:1.5rem 16px 2rem;min-height:0}
.mega h4{margin:0 0 .4rem;font-size:.85rem;text-transform:uppercase;letter-spacing:.06em;color:var(--teal)}
.mega ul{list-style:none;margin:0;padding:0}
.mega li a{display:block;padding:.3rem 0;text-decoration:none;color:var(--ink)}
.mega li a:hover{color:var(--link);text-decoration:underline}

/* ---------- Home ---------- */
.hero{background:var(--paper);border-bottom:1px solid var(--line);position:relative;overflow:hidden}
.hero .wrap{padding:3.2rem 16px 3rem;text-align:center;position:relative}
.hero h1{font-size:2.6rem;margin:0 0 .5rem}
.hero p.lead{font-size:1.2rem;color:var(--muted);max-width:40rem;margin:0 auto 1.5rem}
.hero .suits{position:absolute;inset:0;pointer-events:none;font-size:3rem;opacity:.18}
.hero .suits span{position:absolute}
.choose{display:flex;flex-wrap:wrap;justify-content:center;gap:1rem;margin-top:.5rem}
.choose a{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:1rem 1.2rem;width:15rem;text-decoration:none;color:var(--ink);box-shadow:var(--shadow);text-align:left}
.choose a strong{display:block;color:var(--navy);font-size:1.05rem}
.choose a span{font-size:.92rem;color:var(--muted)}
.choose a:hover{border-color:var(--navy)}

.catalogue{padding:2.5rem 0 1rem}
.catalogue h2.section-title{text-align:center;margin-top:0}
.cat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:2rem 2.5rem;margin-top:1.5rem}
.cat-grid h3{font-size:1.05rem;margin:0 0 .5rem;padding-bottom:.4rem;border-bottom:2px solid var(--gold)}
.cat-grid ul{list-style:none;margin:0;padding:0}
.cat-grid li a{display:block;padding:.28rem 0;color:var(--ink);text-decoration:none}
.cat-grid li a:hover{color:var(--link);text-decoration:underline}
.cat-grid li.see-all a{color:var(--link);font-weight:600}
.soon{font-size:.72rem;font-weight:700;text-transform:uppercase;letter-spacing:.05em;background:var(--gold-soft);color:#6d5520;border-radius:4px;padding:.1rem .4rem;margin-left:.35rem;vertical-align:middle}

.why{background:var(--paper);padding:2.8rem 0;margin-top:2rem;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.why h2{text-align:center;margin-top:0}
.three{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:2rem;margin-top:1.5rem}
.three .icon{width:56px;height:56px;border-radius:50%;background:var(--navy);color:var(--gold);display:grid;place-items:center;font-size:1.6rem;margin-bottom:.6rem}
.three h3{margin:.2rem 0 .3rem}
.three p{margin:0;color:var(--muted)}

.split{display:grid;grid-template-columns:1fr 1fr;gap:3rem;align-items:center;padding:3rem 0}
.split .eyebrow,.eyebrow{font-size:.8rem;text-transform:uppercase;letter-spacing:.08em;color:var(--teal);font-weight:700;margin:0}
.split h2{font-family:var(--serif);font-weight:500;font-size:1.9rem;margin:.3rem 0 .6rem}
.split .art{background:var(--navy);border-radius:16px;min-height:260px;display:grid;place-items:center;padding:2rem}
.split .art img{width:220px}
.banner{background:var(--navy);color:#fff;padding:2.6rem 0;text-align:center}
.banner h2{color:#fff;font-family:var(--serif);font-weight:500;margin:0 0 .4rem}
.banner p{color:#dfe6ef;max-width:42rem;margin:0 auto 1.2rem}

/* ---------- Footer ---------- */
footer.site{background:var(--paper);border-top:1px solid var(--line);margin-top:3rem;font-size:.92rem}
footer.site .cols{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:1.5rem;padding:2.2rem 16px 1rem}
footer.site h4{margin:0 0 .5rem;font-size:.85rem;text-transform:uppercase;letter-spacing:.06em;color:var(--navy)}
footer.site ul{list-style:none;margin:0;padding:0}
footer.site li a{color:var(--ink);text-decoration:none;display:block;padding:.18rem 0}
footer.site li a:hover{text-decoration:underline}
footer.site .legal{border-top:1px solid var(--line);padding:1rem 16px 1.6rem;color:var(--muted)}

/* ---------- Course / section pages (Khan course layout) ---------- */
.course{display:grid;grid-template-columns:300px 1fr;gap:2.5rem;padding:1.8rem 16px 0}
.side{position:sticky;top:84px;align-self:start;max-height:calc(100vh - 100px);overflow:auto;border:1px solid var(--line);border-radius:var(--radius);background:#fff}
.side .side-head{display:flex;gap:.75rem;align-items:center;padding:.9rem 1rem;background:var(--teal-soft);border-left:4px solid var(--teal)}
.side .badge{width:44px;height:44px;border-radius:50%;background:var(--navy);color:var(--gold);display:grid;place-items:center;font-size:1.3rem;flex:none}
.side .side-head strong{display:block;color:var(--navy-deep);line-height:1.25}
.side .side-head small{color:var(--muted);text-transform:uppercase;letter-spacing:.05em;font-size:.75rem;font-weight:700}
.side ol{list-style:none;margin:0;padding:0}
.side li a{display:block;padding:.7rem 1rem;border-top:1px solid var(--line);text-decoration:none;color:var(--ink)}
.side li a small{display:block;text-transform:uppercase;letter-spacing:.05em;font-size:.72rem;color:var(--muted);font-weight:700}
.side li a:hover,.side li a.active{background:var(--paper)}
.side li a.active{box-shadow:inset 4px 0 0 var(--gold)}
.crumbs{font-size:.9rem;color:var(--muted);margin:0 0 .3rem}
.crumbs a{color:var(--link);text-decoration:none}
.crumbs a:hover{text-decoration:underline}
.page-head{border-bottom:1px solid var(--line);padding-bottom:1rem;margin-bottom:1.2rem}
.page-head p.sub{color:var(--muted);font-size:1.08rem;margin:0;max-width:46rem}
.meta-row{display:flex;flex-wrap:wrap;gap:.6rem;margin-top:.9rem}
.chip{display:inline-flex;align-items:center;gap:.35rem;background:var(--paper);border:1px solid var(--line);border-radius:999px;padding:.25rem .8rem;font-size:.88rem}

.summary-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:1rem;margin:1rem 0 2rem}
.summary-grid a{display:block;border:1px solid var(--line);border-radius:var(--radius);padding:.9rem 1rem;text-decoration:none;color:var(--ink);background:#fff}
.summary-grid a:hover{border-color:var(--navy);box-shadow:var(--shadow)}
.summary-grid small{display:block;text-transform:uppercase;letter-spacing:.05em;font-size:.72rem;color:var(--teal);font-weight:700}

.unit{border:1px solid var(--line);border-radius:var(--radius);margin:0 0 1.6rem;background:#fff;scroll-margin-top:90px}
.unit-head{padding:1rem 1.2rem;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;gap:1rem;align-items:baseline;flex-wrap:wrap}
.unit-head h2{margin:0;font-size:1.25rem}
.unit-head .eyebrow{display:block;margin-bottom:.15rem}
.unit-body{display:grid;grid-template-columns:1fr 1fr;gap:0}
.lesson{padding:1rem 1.2rem;border-top:1px solid var(--line)}
.unit-body .lesson:nth-child(-n+2){border-top:0}
.unit-body .lesson:nth-child(odd){border-right:1px solid var(--line)}
.lesson h3{margin:0 0 .35rem;font-size:1.02rem}
.lesson p{margin:0 0 .5rem;color:var(--muted);font-size:.95rem}
.items{list-style:none;margin:0;padding:0}
.items li{margin:.15rem 0}
.items a{display:flex;align-items:center;gap:.6rem;text-decoration:none;color:var(--ink);padding:.3rem 0}
.items a:hover span{text-decoration:underline;color:var(--link)}
.ic{width:28px;height:28px;border:1.5px solid var(--ink);border-radius:5px;display:grid;place-items:center;flex:none;font-size:.85rem;line-height:1}
.ic.read::before{content:"📖";font-size:.85rem}
.ic.listen::before{content:"▶"}
.ic.practise::before{content:"✎"}
.ic.print::before{content:"🖶"}
.ic.teach::before{content:"★"}
.ic.web::before{content:"↗"}
.legend{display:flex;flex-wrap:wrap;gap:1.2rem;font-size:.88rem;color:var(--muted);margin:.4rem 0 1.4rem}
.legend span{display:inline-flex;align-items:center;gap:.4rem}
.legend .ic{width:22px;height:22px;font-size:.7rem}

.challenge{display:flex;gap:1.2rem;align-items:center;background:var(--navy);color:#fff;border-radius:var(--radius);padding:1.3rem 1.5rem;margin:1rem 0 2rem;flex-wrap:wrap}
.challenge h3{color:#fff;margin:0 0 .2rem}
.challenge p{margin:0;color:#dfe6ef}
.challenge .grow{flex:1;min-width:220px}

/* Prose (lesson text) */
.prose{max-width:46rem}
.prose table{border-collapse:collapse;width:100%;margin:1rem 0;font-size:.95rem}
.prose th,.prose td{border:1px solid var(--line);padding:.5rem .7rem;text-align:left;vertical-align:top}
.prose th{background:var(--paper)}
.prose blockquote{margin:1rem 0;padding:.8rem 1rem;background:var(--teal-soft);border-left:4px solid var(--teal);border-radius:0 8px 8px 0}
.prose figure{margin:1.4rem 0}
.prose figure img{border-radius:8px;border:1px solid var(--line);max-height:420px;object-fit:contain;background:var(--paper)}
.prose figcaption{font-size:.88rem;color:var(--muted);margin-top:.35rem}
.prose hr{border:0;border-top:1px solid var(--line);margin:2rem 0}
.prose h2{scroll-margin-top:90px}
.next-prev{display:flex;justify-content:space-between;gap:1rem;border-top:1px solid var(--line);margin-top:2.5rem;padding-top:1.2rem}

.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:1.2rem;margin:1rem 0 2rem}
.tile{border:1px solid var(--line);border-radius:var(--radius);background:#fff;padding:1.1rem 1.2rem;display:flex;flex-direction:column;gap:.4rem}
.tile h3{margin:0;font-size:1.05rem}
.tile p{margin:0;color:var(--muted);font-size:.95rem;flex:1}
.tile .tag{font-size:.72rem;text-transform:uppercase;letter-spacing:.05em;font-weight:700;color:var(--teal)}
.tile a.go{font-weight:600;text-decoration:none}
.tile a.go:hover{text-decoration:underline}
.note{background:var(--gold-soft);border:1px solid #e3cf98;border-radius:var(--radius);padding:.9rem 1.1rem;margin:1rem 0}
.pathway{display:grid;grid-template-columns:repeat(4,1fr);gap:0;margin:1.2rem 0 2rem;counter-reset:step}
.pathway a,.pathway div{position:relative;padding:1rem 1rem 1rem 1.2rem;border:1px solid var(--line);background:#fff;text-decoration:none;color:var(--ink);margin-left:-1px}
.pathway a:first-child,.pathway div:first-child{border-radius:var(--radius) 0 0 var(--radius);margin-left:0}
.pathway a:last-child,.pathway div:last-child{border-radius:0 var(--radius) var(--radius) 0}
.pathway strong{display:block;color:var(--navy);font-size:1.05rem}
.pathway span{font-size:.9rem;color:var(--muted)}
.pathway a:hover{background:var(--paper)}
.pathway .off{opacity:.7}

/* Search results */
.results{list-style:none;padding:0}
.results li{padding:.8rem 0;border-bottom:1px solid var(--line)}
.results small{color:var(--muted);display:block}

/* ---------- Responsive ---------- */
@media (max-width:960px){
  .topbar .wrap{grid-template-columns:auto 1fr auto}
  .brand span{display:none}
  .tb-left{order:2}
  .brand{order:1}
  .tb-right{order:3}
  .search{min-width:0;flex:1}
  .tb-link.hide-sm{display:none}
  .course{grid-template-columns:1fr;gap:1rem}
  .side{position:static;max-height:none}
  .side ol{display:none}
  .side.open ol{display:block}
  .side .side-head{cursor:pointer}
  .split{grid-template-columns:1fr;gap:1.5rem}
  .pathway{grid-template-columns:1fr 1fr}
  .pathway a,.pathway div{border-radius:0!important;margin:0 0 -1px 0}
}
@media (max-width:640px){
  html{font-size:106.25%}
  .hero h1{font-size:2rem}
  .unit-body{grid-template-columns:1fr}
  .unit-body .lesson{border-right:0!important;border-top:1px solid var(--line)!important}
  .unit-body .lesson:first-child{border-top:0!important}
  .tb-right .btn{padding:.5rem .7rem;font-size:.9rem}
  .choose a{width:100%}
  .pathway{grid-template-columns:1fr}
  .search{display:none}
}
@media print{.topbar,footer.site,.side{display:none}.course{display:block}}