@font-face{font-family:'IBM Plex Sans';src:url('assets/IBMPlexSans-Regular.woff2') format('woff2');font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:'IBM Plex Sans';src:url('assets/IBMPlexSans-Medium.woff2') format('woff2');font-weight:500;font-style:normal;font-display:swap}
@font-face{font-family:'IBM Plex Sans';src:url('assets/IBMPlexSans-SemiBold.woff2') format('woff2');font-weight:600 800;font-style:normal;font-display:swap}
@font-face{font-family:'IBM Plex Serif';src:url('assets/IBMPlexSerif-Italic.woff2') format('woff2');font-weight:400;font-style:italic;font-display:swap}
:root{--sans:'IBM Plex Sans',system-ui,Arial,sans-serif;--display:'IBM Plex Sans',system-ui,Arial,sans-serif;--serif:'IBM Plex Serif',Georgia,serif}
body{letter-spacing:.005em}
.nav-group summary{display:block;list-style:none}
.nav-group summary::-webkit-details-marker{display:none}
.nav-group{position:relative}
.nav-group>summary{position:relative;padding:9px 18px 9px 0;cursor:pointer;white-space:nowrap}
.nav-group>summary:after{content:'';position:absolute;right:2px;top:14px;width:6px;height:6px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg);transition:transform .15s}
.nav-group[open]>summary:after{transform:translateY(3px) rotate(225deg)}
.nav-group.current>summary,.nav-group[open]>summary{color:var(--blue-deep)}
.nav-dropdown{position:absolute;top:calc(100% + 10px);left:-16px;z-index:30;display:grid;min-width:240px;padding:8px;background:#fff;border:1px solid var(--line);box-shadow:0 12px 28px rgba(16,39,70,.12)}
.nav-group:not([open])>.nav-dropdown{display:none}
.nav-dropdown a{display:block;padding:11px 12px;white-space:nowrap;font-size:12px;border-radius:2px}
.nav-dropdown a:hover,.nav-dropdown a.current{color:var(--blue-deep);background:var(--mist)}
.nav-about.current{color:var(--blue);text-decoration:underline;text-underline-offset:6px}
.main-nav a:focus-visible,.nav-group>summary:focus-visible,.menu-toggle:focus-visible{outline:2px solid var(--blue);outline-offset:4px}
@media(max-width:820px){
  .main-nav{max-height:calc(100dvh - 100px);overflow-y:auto;overscroll-behavior:contain}
  .nav-group>summary{padding:12px 24px 12px 0;font-size:12px}
  .nav-group>summary:after{top:18px;right:5px}
  .nav-dropdown{position:static;min-width:0;padding:3px 0 8px 12px;border:0;border-top:1px solid var(--line);box-shadow:none}
  .nav-dropdown a{padding:10px 8px;white-space:normal}
}
.hero h1{font-weight:600;letter-spacing:-.049em}
.hero h1 em{font-weight:400;letter-spacing:-.052em}
.hero-art:before{inset:12px 0 39px 30px;background:#edf5ff}
.hero-art-frame{width:min(340px,78%);box-shadow:none;border:8px solid #fff;outline:1px solid #d8e6f5}
.hero-note{bottom:5px;left:30px;align-items:center;font-size:13px;background:#fff;padding:6px 12px 6px 0;z-index:1;color:#3d5b7f}
.hero-note .note-line{margin-top:0}
.hero-index{top:10px;right:6px}
.path-icon{width:39px;height:39px;display:flex;align-items:center;justify-content:flex-start;margin-top:30px;margin-bottom:12px}
.path-icon img{display:block;width:30px;height:30px}
.path-feature .path-icon img{filter:brightness(0) invert(1)}
.path-card h3{font-weight:600}
.section-heading h2,.intro-main h2,.archive-intro h2,.lab-copy h2,.quiz-intro h2,.community-inner h2{font-weight:600}
.search-box img{width:18px;height:18px;flex:none}
.journal-feature h3,.journal-card h3{font-weight:600}
.button{font-weight:600}
@media(max-width:820px){
  .hero{display:flex;flex-direction:column;align-items:stretch;min-height:0;padding-top:48px}
  .hero-copy{max-width:700px;padding-bottom:4px}
  .hero h1{font-size:clamp(44px,7vw,61px)}
  .hero-lede{max-width:610px}
  .hero-art{height:340px;width:100%;max-width:530px;align-self:center;margin-top:12px}
  .hero-art:before{inset:8px 13px 35px 32px}
  .hero-art-frame{width:min(265px,65%)}
  .hero-note{bottom:0;left:34px}
  .hero-bottomline{width:100%}
  .footer-main{display:block}
  .footer-nav{margin-top:28px;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
  .footer-brand{min-width:0}
}
@media(max-width:600px){
  .hero{padding-top:38px}
  .hero h1{font-size:clamp(39px,10vw,53px)}
  .hero-lede{font-size:13px;line-height:1.72}
  .hero-art{min-height:0;height:285px;margin-top:13px;margin-bottom:10px}
  .hero-art:before{inset:8px 10px 29px 23px}
  .hero-art-frame{width:min(222px,64%);border-width:6px}
  .hero-note{left:25px;bottom:1px;font-size:11px}
  .hero-meta{margin-top:22px}
  .path-icon{width:34px;height:34px;margin-top:18px;margin-bottom:9px}
  .path-icon img{width:26px;height:26px}
  .footer-nav{grid-template-columns:repeat(2,minmax(0,1fr))}
}

/* WOC emblem and the education quotation attributed to Heydər Əliyev. */
.hero-art{height:450px;flex-direction:column;gap:16px}
.hero-art:before{background:#eaf2fd;border-color:#d5e4f7;inset:10px 0 112px 30px}
.hero-art-frame{width:min(300px,73%);box-shadow:none;border:7px solid #fff;outline:1px solid #d8e6f5}
.hero-note{position:relative;left:auto;bottom:auto;z-index:1;align-self:center;display:flex;gap:12px;align-items:flex-start;width:min(340px,88%);margin:0;padding:0;background:transparent;color:var(--blue-night)}
.hero-note .note-line{flex:none;width:26px;margin-top:12px}
.hero-note blockquote{margin:0;font:italic 18px/1.4 var(--serif);color:var(--blue-night)}
.hero-note cite{display:block;font:600 10px/1.4 var(--sans);letter-spacing:.08em;color:#5d7390;margin-top:5px;font-style:normal}
@media(max-width:820px){.hero-art{height:385px;gap:13px}.hero-art-frame{width:min(240px,65%)}.hero-art:before{inset:8px 13px 104px 32px}.hero-note{width:min(315px,85%)}}
@media(max-width:600px){.hero-art{height:330px;gap:10px;margin-bottom:15px}.hero-art-frame{width:min(210px,62%);border-width:5px}.hero-art:before{inset:8px 10px 85px 23px}.hero-note{width:min(255px,83%);gap:8px}.hero-note blockquote{font-size:15px}.hero-note cite{font-size:9px;margin-top:3px}.hero-note .note-line{width:19px;margin-top:10px}}
.journal-art{border-color:#ceddec}
.art-blue{background:#dcecff}.art-paper{background:#f2f6fb}.art-grid{background:#e7f1fc}
.diagram-proof{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;gap:8px}.diagram-proof b{width:65px;height:65px;border:1px solid #538ad1;background:#f8fbff;display:grid;place-items:center;color:var(--blue-deep);font:italic 31px var(--serif)}.diagram-proof b:nth-of-type(2){font:600 27px var(--display);background:var(--blue-deep);color:#fff}.diagram-proof i{height:1px;width:26px;background:#7aa3d5}
.diagram-test{position:absolute;left:17%;top:27%;width:66%;background:#fff;border:1px solid #b6cce5;padding:15px 18px;transform:rotate(-3deg);box-shadow:7px 7px 0 #dce7f4}.diagram-test div{display:grid;grid-template-columns:25px 1fr auto;align-items:center;gap:8px;font-size:9px;font-weight:700;color:#3f6598;padding:8px 0;border-bottom:1px solid #dce7f3}.diagram-test div:last-child{border-bottom:0}.diagram-test i{height:1px;background:#b9cae0}.diagram-test b{font-size:8px;letter-spacing:.09em;color:#6387b5;font-weight:500}
.diagram-path{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;gap:8px;background-image:linear-gradient(#c8dbf1 1px,transparent 1px),linear-gradient(90deg,#c8dbf1 1px,transparent 1px);background-size:22px 22px}.diagram-path b{width:47px;height:47px;display:grid;place-items:center;background:#fff;border:1px solid #6d99cd;color:var(--blue-deep);font:600 16px var(--display)}.diagram-path b:last-child{background:var(--blue-deep);color:#fff}.diagram-path i{width:25px;height:1px;background:var(--blue-deep)}
@media(max-width:600px){.diagram-proof b{width:57px;height:57px}}
.quiz-progress{height:3px;background:#e5edf7;margin-top:13px}.quiz-progress span{display:block;width:0;height:100%;background:var(--blue);transition:width .25s ease}
.quiz-next{display:inline-flex;align-items:center;border:0;border-bottom:1px solid #9ebbe4;background:transparent;padding:5px 0;color:var(--blue-deep);font-size:11px;font-weight:700;cursor:pointer;margin:0 0 16px}
.quiz-next:hover{color:var(--blue-night)}.quiz-next[hidden],.quiz-options[hidden]{display:none!important}
.quiz-options button:disabled{cursor:default}.quiz-feedback{line-height:1.65}

.footer-nav{grid-template-columns:repeat(2,minmax(135px,1fr));gap:42px}
@media(max-width:820px){.footer-nav{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:600px){.footer-nav>div:last-child{grid-column:auto}}

/* Keep the page hierarchy clear without decorative numbering. */
.hero-copy{padding-bottom:0}
.hero-note cite{display:flex;flex-direction:column;gap:2px;margin-top:10px;letter-spacing:0}
.hero-note cite strong{font:700 18px/1.35 var(--sans);color:var(--blue-night)}
.hero-note cite span{font:500 12px/1.4 var(--sans);color:#506985}
.section-marker{font-size:11px;color:var(--blue-deep)}
.intro-grid{grid-template-columns:.45fr 1.55fr}
.intro-aside p{margin-top:0}
.path-icon{margin-top:22px}
.olympiad-row{grid-template-columns:1fr auto 25px}
.topic-row{grid-template-columns:1fr 1.1fr 22px}
.topic-row span:nth-child(2){font-size:10px;color:#718197}
.journal-links{display:flex;align-items:center;gap:24px;flex-wrap:wrap}
@media(max-width:820px){
  .intro-aside{display:block}
  .topic-row{grid-template-columns:1fr 22px}
  .topic-row span:nth-child(2){display:none}
}
@media(max-width:600px){
  .journal-links{gap:17px;margin-top:14px}
  .hero-note cite strong{font-size:15px}
  .hero-note cite span{font-size:10px}
  .olympiad-row{grid-template-columns:1fr 17px}
  .topic-row{grid-template-columns:1fr 19px}
  .intro-aside{display:block}
}