/* ===== Hackathon UMI — feuille de style ===== */
:root{
  --bg:#0b0f14; --bg2:#111821; --card:#151e29; --line:#233142;
  --text:#e8eef5; --muted:#9aabbd; --accent:#2fb4d8; --accent2:#f59331; --on-accent:#03212b;
  --radius:18px; --max:1180px;
  --font-fr:'Inter',system-ui,sans-serif; --font-ar:'Cairo','Tahoma',sans-serif;
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--text);font-family:var(--font-fr);line-height:1.6;overflow-x:hidden}
html[lang="ar"] body{font-family:var(--font-ar)}
html[lang="fr"] .ar, html[lang="ar"] .fr{display:none!important}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.container{width:min(var(--max),100% - 32px);margin-inline:auto}
section{padding:96px 0}
h1,h2,h3{line-height:1.2}
.section-title{font-size:clamp(1.8rem,3.5vw,2.6rem);margin-bottom:16px}
.section-title span{color:var(--accent)}
.lead{color:var(--muted);max-width:760px;margin-bottom:40px}
.btn{display:inline-flex;align-items:center;gap:8px;padding:12px 26px;border-radius:999px;font-weight:700;border:2px solid var(--accent);transition:.25s;cursor:pointer;font-family:inherit;font-size:1rem}
.btn-primary{background:var(--accent);color:var(--on-accent)}
.btn-primary:hover{background:transparent;color:var(--accent)}
.btn-ghost{background:transparent;color:var(--accent)}
.btn-ghost:hover{background:var(--accent);color:var(--on-accent)}

/* Header */
header{position:fixed;inset-inline:0;top:0;z-index:50;transition:.3s}
header.scrolled{background:rgba(11,15,20,.92);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:76px;gap:16px}
.logo{display:flex;align-items:center;gap:12px;font-weight:800;font-size:1.15rem}
.logo small{display:block;font-size:.72rem;font-weight:500;color:var(--muted)}
.nav-links{display:flex;gap:28px;list-style:none}
.nav-links a{color:var(--muted);font-weight:500;transition:.2s}
.nav-links a:hover{color:var(--text)}
.nav-actions{display:flex;align-items:center;gap:12px}
.lang-switch{background:var(--card);border:1px solid var(--line);color:var(--text);border-radius:999px;padding:8px 14px;cursor:pointer;font-weight:700;font-family:var(--font-ar)}
.burger{display:none;background:none;border:0;color:var(--text);font-size:1.6rem;cursor:pointer}

/* Hero */
.hero{min-height:100vh;display:flex;align-items:center;text-align:center;position:relative;padding-top:120px;
  background:radial-gradient(ellipse at 20% 10%,rgba(47,180,216,.18),transparent 55%),radial-gradient(ellipse at 85% 80%,rgba(245,147,49,.12),transparent 50%),var(--bg)}
.hero::before{content:"";position:absolute;inset:0;background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);background-size:60px 60px;opacity:.25;mask-image:radial-gradient(circle at center,#000 20%,transparent 70%)}
.hero .container{position:relative}
.badge{display:inline-block;padding:6px 16px;border:1px solid var(--accent);border-radius:999px;color:var(--accent);font-size:.85rem;margin-bottom:24px}
.hero h1{font-size:clamp(2rem,5.5vw,4rem);font-weight:800;margin-bottom:24px}
.hero h1 .hl{color:var(--accent)}
.hero p{color:var(--muted);max-width:680px;margin:0 auto 36px;font-size:1.1rem}
.hero-ctas{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}

/* Stats */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-top:72px}
.stat{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:24px}
.stat b{display:block;font-size:2.2rem;color:var(--accent)}
.stat span{color:var(--muted)}

/* Countdown */
.countdown-wrap{background:var(--bg2);border-block:1px solid var(--line);padding:56px 0;text-align:center}
.countdown-wrap h3{margin-bottom:24px;font-size:1.3rem}
.countdown{display:flex;justify-content:center;gap:18px;flex-wrap:wrap;margin-bottom:28px}
.cd-box{min-width:110px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:18px}
.cd-box b{font-size:2.6rem;display:block;font-variant-numeric:tabular-nums}
.cd-box span{color:var(--muted);font-size:.85rem;text-transform:uppercase;letter-spacing:.08em}

/* Cards */
.grid-4{display:grid;grid-template-columns:repeat(4,1fr);gap:20px}
.grid-2{display:grid;grid-template-columns:repeat(2,1fr);gap:20px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:28px;display:flex;flex-direction:column;gap:14px;transition:.25s}
.card:hover{border-color:var(--accent);transform:translateY(-4px)}
.card .ico{width:52px;height:52px;border-radius:14px;display:grid;place-items:center;background:rgba(47,180,216,.12);font-size:1.6rem}
.card h3{font-size:1.2rem}
.card p{color:var(--muted);flex:1}
.card .btn{align-self:flex-start;padding:8px 18px;font-size:.9rem}

/* About */
.about{display:grid;grid-template-columns:1.1fr .9fr;gap:48px;align-items:center}
.about-visual{aspect-ratio:4/3;border-radius:var(--radius);border:1px solid var(--line);background:linear-gradient(135deg,rgba(47,180,216,.25),rgba(245,147,49,.2)),var(--card);display:grid;place-items:center;font-size:5rem}

/* Challenges */
.tags{display:flex;flex-wrap:wrap;gap:12px;margin-bottom:32px}
.tag{padding:12px 20px;border-radius:999px;background:var(--card);border:1px solid var(--line);font-weight:600;transition:.2s}
.tag:hover{border-color:var(--accent2);color:var(--accent2)}

/* Timeline */
.timeline{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;counter-reset:step}
.step{position:relative;padding:28px;border-radius:var(--radius);background:var(--card);border:1px solid var(--line)}
.step .num{font-size:2.6rem;font-weight:800;color:transparent;-webkit-text-stroke:1.5px var(--accent);line-height:1;margin-bottom:12px}
.step h3{font-size:1.1rem;margin-bottom:8px}
.step small{color:var(--accent2);font-weight:700}
.step p{color:var(--muted);margin-top:8px}

/* Mentors */
.mentors{display:grid;grid-template-columns:repeat(auto-fill,minmax(170px,1fr));gap:20px}
.mentor{text-align:center;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px 14px}
.avatar{width:84px;height:84px;border-radius:50%;margin:0 auto 12px;display:grid;place-items:center;font-weight:800;font-size:1.5rem;background:linear-gradient(135deg,var(--accent),#0080a2);color:var(--on-accent)}
.mentor b{display:block}
.mentor span{color:var(--muted);font-size:.85rem}

/* Partners */
.partners{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:16px}
.partner{height:110px;border-radius:14px;border:1px dashed var(--line);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:6px;color:var(--muted);background:var(--bg2)}
.partner b{color:var(--text)}
.partner small{font-size:.72rem;letter-spacing:.1em;color:var(--accent2)}

/* Register */
.register{background:var(--bg2)}
form{display:grid;grid-template-columns:1fr 1fr;gap:16px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:32px}
form label{display:flex;flex-direction:column;gap:6px;font-weight:600;font-size:.92rem}
form .full{grid-column:1/-1}
input,select,textarea{background:var(--bg);border:1px solid var(--line);color:var(--text);border-radius:10px;padding:12px;font-family:inherit;font-size:1rem}
input:focus,select:focus,textarea:focus{outline:2px solid var(--accent);border-color:transparent}
.form-msg{grid-column:1/-1;color:var(--accent);font-weight:600;display:none}

/* FAQ */
.faq{max-width:860px}
details{background:var(--card);border:1px solid var(--line);border-radius:14px;margin-bottom:12px;padding:0 22px}
summary{cursor:pointer;padding:18px 0;font-weight:700;list-style:none;display:flex;justify-content:space-between;gap:16px}
summary::after{content:"+";color:var(--accent);font-size:1.4rem;line-height:1}
details[open] summary::after{content:"−"}
details p{color:var(--muted);padding-bottom:18px}

/* Footer */
footer{border-top:1px solid var(--line);padding:48px 0 24px;color:var(--muted)}
.foot{display:grid;grid-template-columns:2fr 1fr 1fr;gap:32px;margin-bottom:32px}
.foot h4{color:var(--text);margin-bottom:12px}
.foot ul{list-style:none;display:grid;gap:8px}
.foot a:hover{color:var(--accent)}
.copy{text-align:center;font-size:.85rem;border-top:1px solid var(--line);padding-top:20px}

/* Reveal animation */
.reveal{opacity:0;transform:translateY(24px);transition:.7s}
.reveal.visible{opacity:1;transform:none}

/* Responsive */
@media (max-width:980px){
  .grid-4,.timeline,.stats{grid-template-columns:repeat(2,1fr)}
  .about{grid-template-columns:1fr}
  .foot{grid-template-columns:1fr}
}
@media (max-width:760px){
  .nav-links{display:none;position:absolute;top:76px;inset-inline:0;flex-direction:column;background:var(--bg2);padding:20px 16px;border-bottom:1px solid var(--line)}
  .nav-links.open{display:flex}
  .burger{display:block}
  .nav-actions .btn{display:none}
  section{padding:72px 0}
}
@media (max-width:560px){
  .grid-4,.timeline,.stats,.grid-2,form{grid-template-columns:1fr}
  .cd-box{min-width:72px;padding:12px}
  .cd-box b{font-size:1.8rem}
}


/* --- Ajouts plateforme --- */
.logo .logo-img{background:#fff;border-radius:10px;padding:4px 8px;height:52px;width:auto}
footer .logo-img{height:44px}
.cats{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;grid-column:1/-1}
.cats label{flex-direction:row;align-items:center;gap:10px;background:var(--bg);border:2px solid var(--line);border-radius:12px;padding:14px;cursor:pointer;font-weight:700}
.cats label.on{border-color:var(--accent);background:rgba(47,180,216,.12)}
.cats input{position:absolute;opacity:0;pointer-events:none}
.form-err{grid-column:1/-1;color:#ff8a80;font-weight:600;min-height:1.4em}
.hint{color:var(--muted);font-size:.8rem;font-weight:400}
.check{flex-direction:row!important;align-items:center;font-weight:400!important}
.check input{width:auto}
.done{text-align:center;padding:48px 24px;background:var(--card);border:1px solid var(--accent);border-radius:var(--radius)}
.done .ref{font-size:2rem;font-weight:800;letter-spacing:3px;color:var(--accent);margin-top:12px}
.hidden{display:none!important}
.banner{background:rgba(245,147,49,.12);border:1px solid var(--accent2);color:var(--accent2);padding:12px 18px;border-radius:12px;margin-bottom:20px;font-weight:600}
.banner.closed{background:rgba(255,100,100,.12);border-color:#ff8a80;color:#ff8a80}
.committee{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.committee .card h3{font-size:1.05rem}.committee .card p{font-size:.92rem}
.crit{display:grid;grid-template-columns:repeat(5,1fr);gap:14px}
.crit .card{padding:20px;text-align:center;align-items:center}
@media (max-width:980px){.committee{grid-template-columns:1fr}.crit{grid-template-columns:repeat(2,1fr)}}
@media (max-width:560px){.cats,.crit{grid-template-columns:1fr}}