:root{
  --bg0:#07060a;
  --bg1:#0d0a12;
  --panel: rgba(18, 12, 24, .62);
  --panel2: rgba(14, 10, 18, .72);
  --border: rgba(255, 70, 90, .22);
  --border2: rgba(255, 255, 255, .08);
  --text: rgba(255,255,255,.92);
  --muted: rgba(255,255,255,.72);
  --muted2: rgba(255,255,255,.56);

  --red:#ff2e55;
  --red2:#ff5a6f;
  --redGlow: rgba(255,46,85,.35);

  --shadow: 0 18px 60px rgba(0,0,0,.55);
  --radius: 16px;
}

*{ box-sizing:border-box; }

html,body{ height:100%; }

/* === Kana Rain Canvas === */
#kanaRain{
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  pointer-events: none;
  opacity: .55;
}

/* === Page Background === */
body{
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  margin:0;
  padding: 22px 18px 36px;
  color: var(--text);
  background:
    radial-gradient(1200px 800px at 20% -10%, rgba(255,46,85,.18), transparent 60%),
    radial-gradient(1000px 700px at 90% 10%, rgba(255,110,120,.12), transparent 65%),
    linear-gradient(180deg, var(--bg0), var(--bg1));
  overflow-x:hidden;
}

/* === Center only real UI, not the canvas === */
body > :not(#kanaRain){
  max-width: 980px;
  margin-left:auto;
  margin-right:auto;
  position: relative;
  z-index: 2;
}

h1{ margin:0 0 10px; font-size:22px; letter-spacing:.2px; }
p{ margin:10px 0; color:var(--muted); }
strong{ color:rgba(255,255,255,.95); }
a{ color:var(--red2); text-decoration:none; }
a:hover{ text-decoration:underline; }

code{
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.10);
  padding: 2px 7px;
  border-radius: 10px;
  color: rgba(255,255,255,.9);
}

/* === Tabs === */
.tabs{ display:flex; gap:10px; margin:14px 0 16px; flex-wrap:wrap; }

.tabbtn{
  padding:9px 14px;
  border-radius:999px;
  border:1px solid var(--border2);
  background: rgba(255,255,255,.04);
  color: rgba(255,255,255,.84);
  cursor:pointer;
  font-size:13px;
  transition:.15s;
  backdrop-filter: blur(10px);
}

.tabbtn:hover{
  background: rgba(255,255,255,.06);
  border-color: rgba(255,46,85,.28);
  box-shadow:0 0 0 3px rgba(255,46,85,.10);
}

.tabbtn.active{
  background: linear-gradient(180deg, rgba(255,46,85,.22), rgba(255,46,85,.10));
  border-color: rgba(255,46,85,.45);
  color:#fff;
}

/* === Panels === */
.panel{ display:none; }
.panel.active{ display:block; }

.box{
  background: linear-gradient(180deg, var(--panel), var(--panel2));
  border:1px solid var(--border);
  border-radius:var(--radius);
  padding:16px;
  margin:14px 0;
  box-shadow:var(--shadow);
  backdrop-filter: blur(12px);
  position:relative;
}

.row{ display:flex; gap:14px; flex-wrap:wrap; }
.field{ flex:1 1 280px; display:flex; flex-direction:column; gap:7px; margin:10px 0; }

label{ font-size:12px; color:var(--muted2); }
.small{ font-size:12px; color:rgba(255,255,255,.62); }

input, textarea, select{
  padding:11px 12px;
  border:1px solid rgba(255,255,255,.12);
  border-radius:14px;
  font-size:14px;
  color:#fff;
  background: rgba(0,0,0,.22);
  outline:none;
}

textarea{ min-height:96px; resize:vertical; }

.btns{ display:flex; gap:10px; flex-wrap:wrap; margin-top:8px; }

button{
  padding:10px 14px;
  border:1px solid rgba(255,46,85,.55);
  background: linear-gradient(180deg, rgba(255,46,85,.34), rgba(255,46,85,.18));
  color:#fff;
  border-radius:14px;
  cursor:pointer;
}

.note{ margin-top:10px; font-size:12px; color:rgba(255,255,255,.65); }
.ok{ color:#66ffb0; font-weight:700; }
.bad{ color:#ff6a7e; font-weight:700; }

@media (prefers-reduced-motion: reduce){
  #kanaRain{ display:none; }
}