:root{
  --bg:#ffffff;
  --fg:#1a1a1a;
  --muted:#555555;

  /* Greek theme */
  --card:rgba(13,94,175,.06);
  --border:rgba(13,94,175,.18);

  --accent:#0D5EAF;
  --accent2:#1E88E5;

  --shadow: 0 12px 30px rgba(0,0,0,.10);
  --radius:16px;
}

*{ box-sizing:border-box; }

html{ scroll-behavior:smooth; }

body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial;
  background:var(--bg);
  color:var(--fg);
  line-height:1.55;
}

a{ color:inherit; text-decoration:none; }

.container{
  width:min(1100px, calc(100% - 40px));
  margin:0 auto;
}

/* ================= TOPBAR ================= */
.topbar{
  position:fixed;
  top:0; left:0; right:0;
  z-index:50;
  background: rgba(255,255,255,.88);
  border-bottom:1px solid rgba(0,0,0,.08);
  backdrop-filter: blur(10px);
}

.topbar__inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  height:76px;
  gap:16px;
}

.brand__logo{
  height:120px;
  width:auto;
  display:block;
}

.nav{
  display:flex;
  gap:22px;
  align-items:center;
}

.nav a{
  font-weight:600;
  padding:10px 8px;
  border-radius:10px;
}

.nav a:hover{
  background: rgba(13,94,175,.10);
}

.nav__toggle{
  display:none;
  width:44px;
  height:44px;
  border:1px solid rgba(0,0,0,.12);
  background: rgba(255,255,255,.8);
  border-radius:12px;
  box-shadow: var(--shadow);
  cursor:pointer;
}

.nav__toggle span{
  display:block;
  height:2px;
  width:20px;
  background: var(--fg);
  margin:5px auto;
  border-radius:2px;
}

/* ================= HERO ================= */
.hero{
  position:relative;
  min-height:100vh;
  display:flex;
  align-items:center;
  overflow:hidden;
  padding-top:76px;
}

.hero__video{
  position:absolute;
  inset:0;
  width:100%;
  height:100%;
  object-fit:cover;
  z-index:0;
}

.hero__overlay{
  position:absolute;
  inset:0;
  background: rgba(0,0,0,.22);
  z-index:1;
}

.hero__content{
  position:relative;
  z-index:2;
  padding:68px 0 80px;
  color:white;
}

.hero h1{
  font-size: clamp(34px, 5vw, 56px);
  margin:0 0 10px;
  color:white;
  text-shadow: 0 10px 30px rgba(0,0,0,.6);
}

.hero p{
  margin:0 0 22px;
  font-size: clamp(18px, 2.5vw, 24px);
  font-weight:600;
  color:white;
  max-width: 56ch;
}

/* ================= BUTTON ================= */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 16px;
  border-radius:14px;
  font-weight:700;
  cursor:pointer;
}

.btn--primary{
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  color:white;
}

/* ================= SECTIONS ================= */
.section{
  padding:72px 0;
  border-top:1px solid rgba(0,0,0,.06);
}

.section--alt{
  background: rgba(13,94,175,.04);
}

h2{ font-size:30px; margin:0 0 10px; }

.lead{
  margin:0 0 26px;
  color: var(--muted);
}

/* ================= CARDS ================= */
.cards{
  display:grid;
  grid-template-columns: repeat(3, 1fr);
  gap:18px;
}

.card{
  background:white;
  border:1px solid rgba(13,94,175,.18);
  border-radius: var(--radius);
  padding:18px;
  box-shadow: var(--shadow);
}

/* ================= FORM ================= */
input, textarea{
  width:100%;
  margin-top:8px;
  border:1px solid rgba(13,94,175,.25);
  border-radius:12px;
  padding:12px;
}

input:focus, textarea:focus{
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(13,94,175,.18);
}

/* ================= CONTACT ================= */
#contact .grid{
  display:grid;
  grid-template-columns: 1fr 1fr;
  gap:40px;
  align-items:start;
}

/* ================= TIMELINE ================= */
.timeline{
  position:relative;
  margin-top:40px;
  padding-left:40px;
}

/* orta çizgi */
.timeline::before{
  content:"";
  position:absolute;
  left:18px;
  top:0;
  bottom:0;
  width:2px;
  background: linear-gradient(var(--accent), var(--accent2));
}

/* item */
.timeline-item{
  position:relative;
  margin-bottom:40px;
  display:flex;
  align-items:flex-start;
}

/* nokta */
.timeline .dot{
  position:absolute;
  left:-2px;
  top:6px;
  width:14px;
  height:14px;
  background: var(--accent);
  border:3px solid white;
  border-radius:50%;
  box-shadow: 0 4px 10px rgba(0,0,0,.15);
}

/* içerik */
.timeline .content{
  background:white;
  border:1px solid rgba(13,94,175,.18);
  border-radius:16px;
  padding:16px 18px;
  box-shadow: var(--shadow);
  width:100%;
}

.timeline .content h3{
  margin:0 0 6px;
  color: var(--accent);
}

.timeline .content p{
  margin:0;
  color: var(--muted);
}

/* ================= FOOTER ================= */
.footer{
  padding:26px 0;
  border-top:1px solid rgba(0,0,0,.06);
  color: var(--muted);
}

/* ================= RESPONSIVE ================= */
@media (max-width:1000px){
  .cards{
    grid-template-columns:1fr;
  }
}

@media (max-width:768px){
  #contact .grid{
    grid-template-columns:1fr;
  }

  .timeline{
    padding-left:30px;
  }

  .timeline::before{
    left:14px;
  }
}

@media (max-width:720px){
  .nav{ display:none; }
  .nav__toggle{ display:inline-block; }

  .brand__logo{ height:90px; }
}