*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
  width: 100%; min-height: 100%;
  font-family: 'Nunito Sans', sans-serif;
}

body {
  min-height: 100vh;
  background: radial-gradient(ellipse 120% 100% at 50% 60%, #1a1a3a 0%, #060a1e 55%, #081520 100%);
  overflow-x: hidden;
  position: relative;
}

body::before {
  content: '';
  position: fixed;
  bottom: -650px; left: -700px;
  width: 1600px; height: 1400px;
  background: radial-gradient(ellipse, rgba(0,140,180,0.28) 0%, transparent 65%);
  pointer-events: none;
  z-index: 0;
}

body::after {
  content: '';
  position: fixed;
  top: -600px; right: -500px;
  width: 1700px; height: 1500px;
  background: radial-gradient(ellipse, rgba(55,43,193,0.25) 0%, transparent 65%);
  pointer-events: none;
  z-index: 0;
}

/* ── Header (lobby) ── */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 80px;
  background: #080C1E;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  z-index: 100;
}

.site-header .header-logo {
  height: 80px;
  width: auto;
  display: block;
  margin-top: 1px;
}

.btn-logout {
  padding: 10px 20px;
  border: none;
  border-radius: 10px;
  font-family: 'Nunito', sans-serif;
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: 0.04em;
  color: #fff;
  background: linear-gradient(135deg, #e06010 0%, #f5a800 50%, #ffd040 100%);
  box-shadow: 0 2px 12px rgba(240,140,0,0.4);
  cursor: pointer;
  transition: transform 0.18s, box-shadow 0.18s;
  text-decoration: none;
}

.btn-logout:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(240,160,0,0.5);
}

.btn-logout:active { transform: translateY(0); }

main {
  position: relative;
  z-index: 1;
}