:root{
  --siba-primary:#0d2b4e;      /* lacivert */
  --siba-primary-2:#13406f;
  --siba-accent:#c8a04e;       /* altın vurgusu */
  --siba-light:#f5f7fa;
  --siba-text:#1f2937;
  --siba-muted:#6b7280;
  --siba-border:#e5e7eb;
}

*{box-sizing:border-box}
body{
  font-family:'Inter','Segoe UI',Roboto,Arial,sans-serif;
  color:var(--siba-text);
  margin:0;
  line-height:1.6;
  background:#fff;
}
a{color:var(--siba-primary-2);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto}

/* ---------- Üst bar ---------- */
.topbar{background:var(--siba-primary);color:#cdd7e5;font-size:.85rem}
.topbar a{color:#cdd7e5}
.topbar .inner{display:flex;justify-content:space-between;align-items:center;
  max-width:1180px;margin:0 auto;padding:.45rem 1rem;flex-wrap:wrap;gap:.5rem}
.topbar .social a{margin-left:.6rem}

/* ---------- Navigasyon ---------- */
.navbar-siba{background:#fff;border-bottom:1px solid var(--siba-border);
  position:sticky;top:0;z-index:1000;box-shadow:0 1px 6px rgba(0,0,0,.04)}
.navbar-siba .brand{font-weight:800;font-size:1.4rem;color:var(--siba-primary);
  letter-spacing:.5px;text-decoration:none;display:flex;align-items:center;gap:.5rem}
.navbar-siba .brand-logo{height:64px;width:auto;border-radius:6px;object-fit:contain}
.navbar-siba .brand-text{font-weight:800;color:var(--siba-primary);font-size:1.1rem;line-height:1.15;letter-spacing:.2px}
.navbar-siba .brand .logo{width:40px;height:40px;border-radius:8px;
  background:linear-gradient(135deg,var(--siba-primary),var(--siba-primary-2));
  color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800}
.navbar-siba .nav-link{color:var(--siba-text)!important;font-weight:600;
  padding:.4rem .85rem!important;border-radius:6px}
.navbar-siba .nav-link:hover,.navbar-siba .nav-link.active{
  color:var(--siba-primary)!important;background:var(--siba-light)}
.dropdown-menu{border:1px solid var(--siba-border);box-shadow:0 8px 24px rgba(0,0,0,.08)}

/* ---------- Hero ---------- */
.hero{background:linear-gradient(120deg,var(--siba-primary) 0%,var(--siba-primary-2) 100%);
  color:#fff;padding:5rem 1rem;position:relative;overflow:hidden;
  min-height:600px;display:flex;align-items:center}
.hero-video{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:0}
.hero-overlay{position:absolute;inset:0;z-index:1;
  background:linear-gradient(120deg,rgba(13,43,78,.88) 0%,rgba(19,64,111,.72) 100%)}
.hero .container{position:relative;z-index:2}
.hero h1{font-size:2.6rem;font-weight:800;margin-bottom:1rem;max-width:760px}
.hero p{font-size:1.15rem;color:#dbe6f2;max-width:620px}
.hero .btn-accent{background:var(--siba-accent);border:none;color:#1a1a1a;font-weight:700}
.hero .btn-accent:hover{filter:brightness(1.07)}

/* ---------- İstatistik bandı ---------- */
.stats-band{background:var(--siba-light);padding:3rem 0}
.stat-box{background:#fff;border:1px solid var(--siba-border);border-left:4px solid var(--siba-accent);
  border-radius:8px;padding:1.5rem 1.6rem;height:100%;box-shadow:0 4px 14px rgba(0,0,0,.04)}
.stat-box .num{font-size:2.4rem;font-weight:800;color:var(--siba-accent);line-height:1}
.stat-box .lbl{color:var(--siba-muted);text-transform:uppercase;letter-spacing:.08em;
  font-size:.8rem;margin-top:.5rem;font-weight:600}

/* ---------- Bölüm başlığı ---------- */
.section{padding:4rem 0}
.section-title{font-weight:800;color:var(--siba-primary);margin-bottom:.3rem}
.section-title:after{content:"";display:block;width:60px;height:4px;
  background:var(--siba-accent);border-radius:2px;margin-top:.6rem}
.section-sub{color:var(--siba-muted);margin-bottom:2rem}
.section-title-center:after{margin-left:auto;margin-right:auto}

/* ---------- Kartlar ---------- */
.card-siba{border:1px solid var(--siba-border);border-radius:12px;overflow:hidden;
  background:#fff;height:100%;transition:transform .15s ease,box-shadow .15s ease}
.card-siba:hover{transform:translateY(-4px);box-shadow:0 12px 28px rgba(0,0,0,.08)}
.card-siba .thumb{aspect-ratio:16/10;object-fit:cover;width:100%;background:var(--siba-light)}
.card-siba .body{padding:1.1rem 1.2rem}
.card-siba .title{font-weight:700;color:var(--siba-primary);font-size:1.08rem;margin:.2rem 0 .4rem}
.card-siba .meta{font-size:.82rem;color:var(--siba-muted);display:flex;gap:1rem;flex-wrap:wrap}
.badge-accent{background:var(--siba-accent);color:#1a1a1a;font-weight:600}

/* ---------- Üye (kurul) kartı ---------- */
.member-card{text-align:center;border:1px solid var(--siba-border);border-radius:12px;
  padding:1.4rem 1rem;background:#fff;height:100%}
.member-card .avatar{width:120px;height:120px;border-radius:50%;object-fit:cover;
  margin:0 auto 1rem;border:4px solid var(--siba-light);background:var(--siba-light);
  display:flex;align-items:center;justify-content:center;color:var(--siba-muted);font-size:2.5rem}
.member-card .m-name{font-weight:700;color:var(--siba-primary);margin-bottom:.1rem}
.member-card .m-title{color:var(--siba-accent);font-weight:600;font-size:.9rem}

/* ---------- İçerik / makale ---------- */
.page-head{background:var(--siba-light);padding:2.5rem 0;border-bottom:1px solid var(--siba-border)}
.page-head h1{color:var(--siba-primary);font-weight:800;margin:0}
.breadcrumb-siba{font-size:.85rem;color:var(--siba-muted)}
.prose{font-size:1.05rem;color:#374151}
.prose h2,.prose h3{color:var(--siba-primary);margin-top:1.6rem}
.prose img{border-radius:8px;margin:1rem 0}
.prose blockquote{border-left:4px solid var(--siba-accent);padding-left:1rem;
  color:var(--siba-muted);font-style:italic;margin:1.2rem 0}
.article-abstract{background:var(--siba-light);border-left:4px solid var(--siba-primary);
  padding:1.2rem 1.4rem;border-radius:8px;margin:1.4rem 0}
.article-abstract h4{color:var(--siba-primary);font-weight:700;margin:0 0 .4rem}
.keywords .kw{display:inline-block;background:var(--siba-light);border:1px solid var(--siba-border);
  border-radius:20px;padding:.2rem .8rem;font-size:.8rem;margin:.15rem .2rem 0;color:var(--siba-muted)}

/* ---------- Kayan foto şeridi (marquee) ---------- */
.marquee{overflow:hidden;width:100%;-webkit-mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent);
  mask-image:linear-gradient(90deg,transparent,#000 6%,#000 94%,transparent)}
.marquee-track{display:flex;gap:1rem;width:max-content;animation:marquee 45s linear infinite}
.marquee:hover .marquee-track{animation-play-state:paused}
.marquee-item{flex:0 0 auto;display:block}
.marquee-item img{height:230px;width:auto;border-radius:12px;object-fit:cover;
  box-shadow:0 6px 18px rgba(0,0,0,.10)}
@keyframes marquee{from{transform:translateX(0)}to{transform:translateX(-50%)}}
@media(max-width:768px){.marquee-item img{height:160px}}

/* ---------- Galeri ---------- */
.gallery-grid img{aspect-ratio:1/1;object-fit:cover;width:100%;border-radius:10px;cursor:pointer}
.video-wrap{position:relative;padding-bottom:56.25%;height:0;border-radius:10px;overflow:hidden;background:#000}
.video-wrap iframe,.video-wrap video{position:absolute;inset:0;width:100%;height:100%;border:0}

/* ---------- Yan menü (alt sayfalar) ---------- */
.side-nav{border:1px solid var(--siba-border);border-radius:12px;overflow:hidden}
.side-nav a{display:block;padding:.75rem 1.1rem;color:var(--siba-text);
  border-bottom:1px solid var(--siba-border);font-weight:600}
.side-nav a:last-child{border-bottom:0}
.side-nav a:hover{background:var(--siba-light);text-decoration:none}
.side-nav a.active{background:var(--siba-primary);color:#fff}



/* ---------- Fırsat (özellik) kartları ---------- */
.feature-item{text-align:center;padding:.5rem .75rem}
.feature-icon{width:74px;height:74px;border-radius:50%;background:#e8eef7;color:var(--siba-primary-2);
  display:flex;align-items:center;justify-content:center;font-size:1.9rem;margin:0 auto 1.1rem;
  transition:transform .15s ease}
.feature-item:hover .feature-icon{transform:translateY(-4px)}
.feature-item h3{font-size:1.05rem;font-weight:700;color:var(--siba-primary);margin-bottom:.5rem}
.feature-item p{color:var(--siba-muted);font-size:.92rem;margin:0;line-height:1.55}
.section.pt-0{padding-top:0}

/* ---------- Footer ---------- */
.footer{background:var(--siba-primary);color:#c4d0e0;padding:3rem 0 1.5rem}
.footer h5{color:#fff;font-weight:700;margin-bottom:1rem}
.footer-brand{display:inline-flex;flex-direction:column;align-items:center;text-align:center;gap:.55rem;color:#fff;
  font-weight:800;font-size:1.15rem;text-decoration:none;margin-bottom:.9rem;line-height:1.15}
.footer-brand:hover{color:#fff;text-decoration:none;opacity:.92}
.footer-logo{height:128px;width:auto;border-radius:8px;object-fit:contain}
.footer a{color:#c4d0e0}
.footer a:hover{color:#fff}
.footer .copyright{border-top:1px solid rgba(255,255,255,.12);margin-top:2rem;
  padding-top:1.2rem;font-size:.85rem;color:#9fb0c5}

/* ---------- Yardımcı ---------- */
.btn-siba{background:var(--siba-primary);border:none;color:#fff;font-weight:600}
.btn-siba:hover{background:var(--siba-primary-2);color:#fff}
.empty-state{text-align:center;color:var(--siba-muted);padding:3rem 1rem}

@media(max-width:768px){
  .hero h1{font-size:1.9rem}
  .hero{padding:3rem 1rem;min-height:420px}
  .section{padding:2.5rem 0}
}