/* ====== Reset ====== */
*,
*::before,
*::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; height: 100%; }
body { overflow: hidden; background: #000; color: #fff; font-family: system-ui, -apple-system, "Segoe UI", sans-serif; }

/* ====== Fullscreen background layers ====== */
.bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  background: #000;
}

.bg-layer {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
  filter: blur(14px) saturate(0.95) contrast(1.05);
  transform: scale(1.06);
  opacity: 0;
  transition: opacity 650ms ease;
}

.bg-layer.is-visible { opacity: 1; }

/* dark overlay + vignette so text readable */
.bg-vignette{
  position: absolute;
  inset: 0;
  background:
    radial-gradient(900px 600px at 50% 45%, rgba(0,0,0,0.35), rgba(0,0,0,0.82) 70%, rgba(0,0,0,0.93)),
    linear-gradient(180deg, rgba(0,0,0,0.65), rgba(0,0,0,0.82));
  pointer-events: none;
}

#webgl{
  filter: drop-shadow(0 18px 60px rgba(0,0,0,0.6));
}


/* ====== WebGL canvas ====== */
#webgl{
  position: fixed;
  inset: 0;
  z-index: 1;
  width: 100vw;
  height: 100vh;
  display: block;
}

/* ====== UI ====== */
.ui-top{
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 2;
  padding: 22px 22px 0;
  display: flex;
  justify-content: space-between;
  pointer-events: none; /* 자잘한 클릭 방지, 링크/버튼만 켬 */
}

.ui-left{ width: 260px; pointer-events: none; }
.ui-brand{
  font-size: 18px;
  font-weight: 600;
  opacity: 0.9;
  margin-bottom: 14px;
  pointer-events: none;
}

.ui-list{
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: auto;
}

.ui-item{
  border: 0;
  background: transparent;
  color: rgba(255,255,255,0.55);
  padding: 6px 6px;
  text-align: left;
  cursor: pointer;
  font-size: 14px;
  letter-spacing: 0.05em;
  transition: color 200ms ease, transform 200ms ease;
}
.ui-item:hover{ color: rgba(255,255,255,0.95); transform: translateX(2px); }
.ui-item.is-active{ color: rgba(255,255,255,1); }

.ui-right{
  text-align: right;
  pointer-events: auto;
}
.ui-name{
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.18em;
  opacity: 0.9;
  margin-bottom: 10px;
  text-transform: uppercase;
}
.ui-nav{
  display: flex;
  gap: 22px;
  justify-content: flex-end;
}
.ui-nav a{
  color: rgba(255,255,255,0.75);
  text-decoration: none;
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}
.ui-nav a:hover{ color: rgba(255,255,255,1); text-decoration: underline; }

/* bottom controls */
.ui-bottom{
  position: fixed;
  left: 50%;
  bottom: 38px;
  transform: translateX(-50%);
  z-index: 2;
  display: flex;
  gap: 10px;
  pointer-events: auto;
}
.ui-arrow{
  width: 56px;
  height: 56px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.22);
  background: rgba(255,255,255,0.10);
  color: rgba(255,255,255,0.92);
  font-size: 18px;
  cursor: pointer;
  transition: transform 160ms ease, background 200ms ease;
}
.ui-arrow:hover{ transform: translateY(-1px); background: rgba(255,255,255,0.14); }
.ui-arrow:active{ transform: translateY(0) scale(0.98); }
.ui-arrow.is-accent{
  border-color: rgba(120,170,255,0.55);
  background: rgba(120,170,255,0.18);
}

/* small hint */
.ui-hint{
  position: fixed;
  left: 22px;
  bottom: 18px;
  z-index: 2;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(255,255,255,0.55);
  pointer-events: none;
}

/* responsive */
@media (max-width: 880px){
  .ui-left{ width: 190px; }
  .ui-item{ font-size: 12px; }
  .ui-nav{ gap: 14px; }
}
@media (max-width: 720px){
  .ui-left{ display: none; }
  .ui-top{ padding: 16px 16px 0; }
  .ui-hint{ left: 16px; bottom: 14px; }
}