:root{
  --black:#000000;
  --panel:#111113;
  --card:#0D0D0F;
  --white:#F5F5F7;
  --text-secondary:#86868B;
  --accent:#2E9BFF;
  --green:#34C759;
  --red:#FF453A;
  --yellow:#FFD60A;
  --line:rgba(245,245,247,0.1);
  --line-strong:rgba(245,245,247,0.18);
}
*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth; color-scheme:dark; background-color:#000000;}
body{
  background-color:#000000; background:var(--black); color:var(--white);
  font-family:'Inter',-apple-system,BlinkMacSystemFont,sans-serif;
  -webkit-font-smoothing:antialiased; overflow-x:hidden;
  min-height:100vh;
}
.mono{font-family:'JetBrains Mono',monospace;}
a{color:inherit;text-decoration:none;}
::selection{background:var(--accent);color:var(--white);}
:focus-visible{outline:2px solid var(--accent); outline-offset:3px;}
@media (prefers-reduced-motion: reduce){*{animation-duration:0.01ms !important; transition-duration:0.01ms !important;}}

/* NAV */
nav{position:fixed; top:0; left:0; right:0; z-index:100; display:flex; align-items:center; justify-content:space-between; padding:18px 5vw; background:rgba(0,0,0,0.6); backdrop-filter:blur(20px) saturate(180%); border-bottom:1px solid transparent; transition:border-color .3s, background .3s;}
nav.scrolled{border-bottom-color:var(--line); background:rgba(0,0,0,0.85);}
.logo{font-weight:700; font-size:15px; letter-spacing:0.5px;}
.nav-links{display:flex; gap:32px; align-items:center;}
.nav-links a{font-size:13px; font-weight:500; color:var(--text-secondary); transition:color .2s;}
.nav-links a:hover, .nav-links a.active{color:var(--white);}
.btn-pill{font-size:13px; font-weight:500; background:var(--white); color:var(--black); padding:9px 20px; border-radius:980px; transition:background .2s;}
.btn-pill:hover{background:#e0e0e0;}
.btn-pill-outline{font-size:13px; font-weight:500; background:transparent; color:var(--white); padding:9px 20px; border-radius:980px; border:1px solid rgba(245,245,247,0.3); transition:border-color .2s, background .2s;}
.btn-pill-outline:hover{border-color:var(--white); background:rgba(255,255,255,0.05);}
.nav-toggle{display:none; background:none; border:none; color:var(--white); font-size:22px; cursor:pointer;}
@media (max-width:860px){
  .nav-links{position:fixed; top:58px; left:0; right:0; flex-direction:column; align-items:stretch; gap:0; background:rgba(0,0,0,0.97); backdrop-filter:blur(20px); max-height:0; overflow:hidden; transition:max-height .35s ease;}
  .nav-links.open{max-height:500px; border-bottom:1px solid var(--line);}
  .nav-links a{padding:18px 24px; border-bottom:1px solid var(--line);}
  .nav-links .btn-pill, .nav-links .btn-pill-outline{margin:16px 24px; text-align:center;}
  .nav-toggle{display:block;}
}

/* HERO (home) */
.hero{min-height:92vh; display:flex; flex-direction:column; align-items:center; justify-content:center; text-align:center; padding:140px 24px 60px;}
.hero h1{font-size:clamp(40px, 7vw, 88px); font-weight:700; line-height:1.05; letter-spacing:-2px; max-width:1100px;}
.hero p.sub{font-size:clamp(17px,2vw,21px); color:var(--text-secondary); max-width:600px; margin:24px auto 36px; line-height:1.5;}
.hero-ctas{display:flex; gap:14px; justify-content:center; flex-wrap:wrap;}

/* PAGE HEADER (inner pages) */
.page-header{padding:160px 5vw 70px; max-width:1300px; margin:0 auto; text-align:center;}
.page-header .eyebrow{font-size:14px; font-weight:600; color:var(--accent); margin-bottom:18px;}
.page-header h1{font-size:clamp(34px,5.5vw,60px); font-weight:700; letter-spacing:-1.5px; line-height:1.08;}
.page-header p{font-size:clamp(15px,1.6vw,18px); color:var(--text-secondary); max-width:620px; margin:20px auto 0; line-height:1.6;}

.eyebrow{font-size:14px; font-weight:600; color:var(--accent); margin-bottom:20px;}
.btn-primary-lg{font-size:16px; font-weight:500; background:var(--accent); color:var(--white); padding:14px 30px; border-radius:980px; transition:filter .2s; display:inline-block;}
.btn-primary-lg:hover{filter:brightness(1.15);}
.btn-secondary-lg{font-size:16px; font-weight:500; background:transparent; color:var(--white); padding:14px 30px; border-radius:980px; border:1px solid rgba(245,245,247,0.25); transition:border-color .2s; display:inline-block;}
.btn-secondary-lg:hover{border-color:var(--white);}

/* SECTION SHARED */
.section{padding:100px 5vw; max-width:1300px; margin:0 auto;}
.section-head{text-align:center; margin-bottom:56px;}
.section-head .tag{font-size:13px; font-weight:600; color:var(--accent); margin-bottom:14px; display:block;}
.section-head h2{font-size:clamp(28px,4vw,42px); font-weight:700; letter-spacing:-1px;}
.section-head p{color:var(--text-secondary); max-width:520px; margin:14px auto 0; font-size:16px; line-height:1.6;}
.section-head.left{text-align:left; margin-bottom:40px;}
.section-head.left p{margin:14px 0 0;}

/* PROBLEM CARDS */
.problems-section{padding:120px 5vw 100px; max-width:1300px; margin:0 auto;}
.problem-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:20px;}
.problem-card{
  background:var(--card); border:1px solid var(--line); border-radius:16px;
  padding:28px 24px; transition:border-color .25s, transform .25s;
  display:flex; flex-direction:column; min-height:190px;
}
.problem-card:hover{border-color:var(--line-strong); transform:translateY(-4px);}
.p-num{font-size:13px; color:var(--text-secondary); margin-bottom:16px;}
.p-title{font-size:18px; font-weight:600; margin-bottom:auto; line-height:1.3;}
.p-desc{font-size:14px; color:var(--text-secondary); line-height:1.6; margin-bottom:20px;}
.p-meta{display:flex; flex-direction:column; gap:8px; margin-top:20px;}
.p-tag{font-size:12px; color:var(--text-secondary);}
.p-diff{font-size:12px; font-weight:600; display:flex; align-items:center; gap:6px;}
.p-diff .dot{width:6px; height:6px; border-radius:50%;}
.p-diff.easy .dot{background:var(--green);} .p-diff.easy{color:var(--green);}
.p-diff.medium .dot{background:var(--accent);} .p-diff.medium{color:var(--accent);}
.p-diff.hard .dot{background:var(--red);} .p-diff.hard{color:var(--red);}
.p-try{padding:10px 20px; font-size:13px; align-self:flex-start; margin-top:20px;}

.locked-card{
  position:relative; overflow:hidden; border-radius:16px; border:1px solid var(--line);
  display:flex; align-items:center; justify-content:center; min-height:190px;
  background:var(--card);
}
.locked-code{
  position:absolute; inset:0; padding:24px; font-size:11px; line-height:1.9;
  color:rgba(245,245,247,0.35); filter:blur(2.5px); opacity:0.6;
  white-space:pre; overflow:hidden;
}
.locked-overlay{
  position:relative; z-index:2; text-align:center; padding:20px;
  background:rgba(13,13,15,0.55); backdrop-filter:blur(1px);
  width:100%; height:100%; display:flex; flex-direction:column; align-items:center; justify-content:center;
}
.lock-icon{font-size:20px; margin-bottom:10px; opacity:0.8;}
.locked-overlay strong{font-size:15px; font-weight:600; display:block; margin-bottom:4px;}
.locked-overlay span{font-size:12px; color:var(--text-secondary);}
.problem-grid.featured{grid-template-columns:1fr 2fr;}
.featured-card{padding:32px 28px;}
.featured-card .p-title{font-size:22px; margin-bottom:10px;}
.locked-card.wide{min-height:260px;}
@media (max-width:860px){.problem-grid.featured{grid-template-columns:1fr;}}
@media (max-width:960px){.problem-grid{grid-template-columns:repeat(2,1fr);}}
@media (max-width:560px){.problem-grid{grid-template-columns:1fr;}}

/* FILTER CHIPS */
.filter-row{display:flex; gap:10px; flex-wrap:wrap; margin-bottom:40px; justify-content:center;}
.chip{font-size:13px; font-weight:500; padding:8px 18px; border-radius:980px; border:1px solid var(--line); color:var(--text-secondary); background:transparent; cursor:pointer; transition:all .2s;}
.chip:hover{border-color:var(--line-strong); color:var(--white);}
.chip.active{background:var(--white); color:var(--black); border-color:var(--white);}

/* FEATURE ROWS */
.feature-row{display:grid; grid-template-columns:1fr 1fr; gap:80px; align-items:center; padding:110px 5vw; max-width:1400px; margin:0 auto;}
.feature-row.reverse{direction:rtl;}
.feature-row.reverse > *{direction:ltr;}
.feature-text .tag{font-size:13px; font-weight:600; color:var(--accent); margin-bottom:16px; display:block;}
.feature-text h2{font-size:clamp(28px,3.5vw,42px); font-weight:700; letter-spacing:-1px; line-height:1.1; margin-bottom:18px;}
.feature-text p{font-size:17px; color:var(--text-secondary); line-height:1.65; margin-bottom:26px; max-width:440px;}
.feature-media{aspect-ratio:4/3; border-radius:16px; background:linear-gradient(135deg,#161618,#0a0a0b); border:1px solid var(--line); display:flex; align-items:center; justify-content:center; position:relative; overflow:hidden;}
.feature-media img{position:absolute; inset:0; width:100%; height:100%; object-fit:cover; object-position:center;}
.img-tag{position:absolute; top:14px; left:14px; z-index:3; font-size:10px; font-weight:600; letter-spacing:0.5px; text-transform:uppercase; background:rgba(0,0,0,0.6); backdrop-filter:blur(6px); color:var(--text-secondary); padding:6px 10px; border-radius:6px; border:1px solid var(--line);}
@media (max-width:860px){.feature-row, .feature-row.reverse{grid-template-columns:1fr; gap:32px; padding:80px 24px;} .feature-row.reverse{direction:ltr;}}

/* GOALS */
.goals-section{border-top:1px solid var(--line); border-bottom:1px solid var(--line); padding:90px 5vw; max-width:1300px; margin:0 auto;}
.goals-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:40px; text-align:center; margin-top:8px;}
.stat-num{font-size:clamp(30px,4vw,48px); font-weight:700; letter-spacing:-1px;}
.stat-label{font-size:14px; color:var(--text-secondary); margin-top:8px;}
.stat-target{font-size:11px; color:var(--text-secondary); opacity:0.6; margin-top:2px; letter-spacing:0.5px; text-transform:uppercase;}
@media (max-width:700px){.goals-grid{grid-template-columns:repeat(2,1fr); gap:40px 24px;}}

/* ROADMAP / LIST ROWS */
.roadmap-section{padding:100px 5vw; max-width:900px; margin:0 auto;}
.roadmap-list{border-top:1px solid var(--line);}
.rm-row{display:grid; grid-template-columns:140px 1fr 120px; gap:24px; align-items:center; padding:22px 0; border-bottom:1px solid var(--line);}
.rm-date{font-size:13px; color:var(--text-secondary); font-weight:500;}
.rm-title{font-size:17px; font-weight:600;}
.rm-title small{display:block; font-size:13px; color:var(--text-secondary); font-weight:400; margin-top:2px;}
.rm-status{font-size:12px; font-weight:600; text-align:right; letter-spacing:0.3px;}
.rm-status.next{color:var(--accent);}
.rm-status.upcoming{color:var(--text-secondary);}
@media (max-width:600px){.rm-row{grid-template-columns:1fr; gap:6px; text-align:left;} .rm-status{text-align:left;}}

/* LEADERBOARD */
.lb-section{padding:0 5vw 130px; max-width:800px; margin:0 auto;}
.lb-note{font-size:12px; color:var(--text-secondary); text-align:center; margin-top:-32px; margin-bottom:40px;}
.lb-list{border-top:1px solid var(--line);}
.lb-row{display:grid; grid-template-columns:40px 1fr 100px 90px; gap:16px; align-items:center; padding:16px 0; border-bottom:1px solid var(--line);}
.lb-rank{font-size:14px; font-weight:700; color:var(--text-secondary);}
.lb-row.gold .lb-rank{color:var(--yellow);}
.lb-row.silver .lb-rank{color:#D0D0D5;}
.lb-row.bronze .lb-rank{color:#C77B3E;}
.lb-name{font-size:15px; font-weight:600;}
.lb-region{font-size:13px; color:var(--text-secondary);}
.lb-score{font-size:14px; font-weight:600; text-align:right;}
.lb-cta{text-align:center; margin-top:28px;}
.link-arrow{font-size:14px; color:var(--accent);}
.link-arrow:hover{text-decoration:underline;}

/* GENERIC CARD GRID (hub / team / sponsors / eligibility) */
.card-grid{display:grid; grid-template-columns:repeat(4,1fr); gap:20px;}
.card-grid.cols-3{grid-template-columns:repeat(3,1fr);}
.card-grid.cols-2{grid-template-columns:repeat(2,1fr);}
.info-card{
  background:var(--card); border:1px solid var(--line); border-radius:16px;
  padding:28px 24px; transition:border-color .25s, transform .25s;
  display:flex; flex-direction:column; min-height:170px;
}
a.info-card:hover{border-color:var(--line-strong); transform:translateY(-4px);}
.info-label{font-size:12px; font-weight:600; color:var(--accent); margin-bottom:14px; letter-spacing:0.3px;}
.info-title{font-size:18px; font-weight:600; margin-bottom:8px;}
.info-desc{font-size:14px; color:var(--text-secondary); line-height:1.55; margin-bottom:auto;}
.info-link{font-size:13px; color:var(--white); margin-top:20px; display:inline-flex; align-items:center; gap:5px; font-weight:500;}
a.info-card:hover .info-link{color:var(--accent);}
@media (max-width:960px){.card-grid, .card-grid.cols-3{grid-template-columns:repeat(2,1fr);}}
@media (max-width:560px){.card-grid, .card-grid.cols-3, .card-grid.cols-2{grid-template-columns:1fr;}}

/* TEAM */
.team-card{text-align:center; align-items:center;}
.team-photo{width:88px; height:88px; border-radius:50%; margin:0 auto 18px; overflow:hidden; border:1px solid var(--line); position:relative; background:linear-gradient(135deg,#1a1a1d,#0d0d0f);}
.team-photo img{width:100%; height:100%; object-fit:cover;}
.team-name{font-size:16px; font-weight:600;}
.team-role{font-size:13px; color:var(--accent); margin-top:4px;}
.team-bio{font-size:13px; color:var(--text-secondary); margin-top:10px; line-height:1.55;}

/* FORM (register) */
.form-wrap{max-width:640px; margin:0 auto; padding:0 5vw 140px;}
.form-card{background:var(--card); border:1px solid var(--line); border-radius:20px; padding:44px;}
.field{margin-bottom:22px;}
.field label{display:block; font-size:13px; font-weight:600; margin-bottom:8px; color:var(--white);}
.field .hint{font-size:12px; color:var(--text-secondary); margin-top:6px;}
.field input, .field select, .field textarea{
  width:100%; padding:12px 14px; border-radius:10px; border:1px solid var(--line-strong);
  background:#0A0A0B; color:var(--white); font-size:14px; font-family:inherit;
  transition:border-color .2s;
}
.field input::placeholder, .field textarea::placeholder{color:#54545C;}
.field input:focus, .field select:focus, .field textarea:focus{outline:none; border-color:var(--accent);}
.field-row{display:grid; grid-template-columns:1fr 1fr; gap:16px;}
@media (max-width:600px){.field-row{grid-template-columns:1fr;} .form-card{padding:28px 22px;}}
.form-submit{width:100%; text-align:center; margin-top:8px; border:none; cursor:pointer;}
.form-note{font-size:12px; color:var(--text-secondary); text-align:center; margin-top:18px; line-height:1.6;}

/* FINAL CTA */
.final-cta{text-align:center; padding:150px 24px; border-top:1px solid var(--line);}
.final-cta h2{font-size:clamp(32px,5vw,52px); font-weight:700; letter-spacing:-1.5px; margin-bottom:18px;}
.final-cta p{font-size:17px; color:var(--text-secondary); margin-bottom:36px;}

footer{border-top:1px solid var(--line); padding:56px 5vw 40px; max-width:1400px; margin:0 auto;}
.footer-top{display:flex; justify-content:space-between; flex-wrap:wrap; gap:32px; margin-bottom:40px;}
.footer-links{display:flex; gap:32px; flex-wrap:wrap;}
.footer-links a{font-size:13px; color:var(--text-secondary);}
.footer-links a:hover{color:var(--white);}
.footer-copy{font-size:12px; color:var(--text-secondary);}

.reveal{opacity:0; transform:translateY(28px); transition:opacity .8s cubic-bezier(.16,1,.3,1), transform .8s cubic-bezier(.16,1,.3,1);}
.reveal.in{opacity:1; transform:translateY(0);}