/* ============================================================
   lphp.jp トップ改装・案C：ファーストビューの背景「オーロラ」
   青・水色・紫の大きな光がゆっくり漂う＋細かい点（2026-09-28 見比べで決定。設計図・夜の青の案は不採用）
   ============================================================ */
.heroC{background:linear-gradient(180deg,#EEF3FF 0%,#FFFFFF 55%,#EFF4FF 100%)}
.heroC::before{display:none}
.heroC > .fv-bg{position:absolute;inset:0;pointer-events:none;overflow:hidden}
.fv-bg i{position:absolute;display:block;border-radius:50%;will-change:transform}
.fv-bg i:nth-child(1){width:max(170vw,860px);aspect-ratio:1;left:-60%;top:-420px;
  background:radial-gradient(circle,rgba(27,79,232,.46) 0%,rgba(27,79,232,.16) 36%,rgba(27,79,232,0) 66%);animation:bgA1 22s ease-in-out infinite alternate}
.fv-bg i:nth-child(2){width:max(150vw,760px);aspect-ratio:1;right:-70%;top:40px;
  background:radial-gradient(circle,rgba(0,184,255,.40) 0%,rgba(0,184,255,.12) 38%,rgba(0,184,255,0) 66%);animation:bgA2 26s ease-in-out infinite alternate}
.fv-bg i:nth-child(3){width:max(140vw,720px);aspect-ratio:1;left:-35%;top:420px;
  background:radial-gradient(circle,rgba(124,77,255,.30) 0%,rgba(124,77,255,.09) 40%,rgba(124,77,255,0) 66%);animation:bgA3 30s ease-in-out infinite alternate}
.fv-bg i:nth-child(4){inset:0;border-radius:0;will-change:auto;
  background-image:radial-gradient(rgba(14,46,171,.14) 1px,transparent 1.3px);background-size:20px 20px;
  -webkit-mask-image:linear-gradient(180deg,#000 0%,rgba(0,0,0,.2) 60%,#000 100%);mask-image:linear-gradient(180deg,#000 0%,rgba(0,0,0,.2) 60%,#000 100%)}
@keyframes bgA1{from{transform:translate(0,0) scale(1)}to{transform:translate(22%,12%) scale(1.15)}}
@keyframes bgA2{from{transform:translate(0,0) scale(1.05)}to{transform:translate(-26%,14%) scale(.9)}}
@keyframes bgA3{from{transform:translate(0,0) scale(.95)}to{transform:translate(30%,-14%) scale(1.12)}}
@media (prefers-reduced-motion:reduce){.fv-bg i{animation:none!important}}