:root{
  --bg:#071a12;--panel:#0f2a1c;--text:#e8f5e9;--muted:#8fbc9a;
  --warn:#fbbf24;--good:#4ade80;--touch:72px;
}
*{box-sizing:border-box;margin:0;padding:0;-webkit-tap-highlight-color:transparent}
body{
  min-height:100dvh;font-family:"PingFang TC","Noto Sans TC",system-ui,sans-serif;
  background:radial-gradient(ellipse at 40% 0%,#14532d,transparent 50%),var(--bg);
  color:var(--text);
  padding:max(.5rem,env(safe-area-inset-top)) .7rem max(.5rem,env(safe-area-inset-bottom));
  user-select:none;
}
button{font:inherit;border:none;cursor:pointer;color:inherit}
button:active:not(:disabled){transform:scale(.98)}
button:disabled{opacity:.45}
.app{max-width:520px;margin:0 auto;min-height:calc(100dvh - 1rem);display:flex;flex-direction:column}
.screen{display:flex;flex-direction:column;gap:.5rem;flex:1;min-height:0}
.hidden{display:none!important}
.top{text-align:center}
.top h1{font-size:clamp(1.05rem,3.6vw,1.35rem);color:var(--good);font-weight:900}
.gentle{color:var(--muted);font-weight:600;margin-top:.3rem}
.panel{
  background:var(--panel);border-radius:16px;padding:.9rem;
  border:1px solid rgba(74,222,128,.25);
}
.label{color:var(--warn);font-weight:800;margin:.35rem 0}
.chips{display:flex;flex-wrap:wrap;gap:.4rem}
.chip,.chips button{
  min-height:var(--touch);padding:.55rem .9rem;border-radius:16px;
  background:rgba(0,0,0,.34);border:3px solid rgba(143,188,154,.45);font-weight:900;font-size:1.05rem;
}
.chip.active,.chips button.active{border-color:var(--warn);background:rgba(251,191,36,.28);color:#fde68a;box-shadow:0 0 0 3px rgba(251,191,36,.35)}
.cur{font-weight:800}.cur span{color:var(--warn)}
.hint{color:var(--muted);font-weight:600;line-height:1.45}
.btn-go{
  width:100%;min-height:68px;margin-top:.5rem;border-radius:16px;font-weight:900;font-size:1.1rem;
  background:linear-gradient(180deg,#86efac,#16a34a);color:#052e16;
}
.btn.ghost{
  width:100%;min-height:52px;margin-top:.35rem;border-radius:14px;font-weight:800;
  background:rgba(0,0,0,.25);
}
.online-panel{margin-top:.45rem;padding-top:.4rem;border-top:1px dashed rgba(74,222,128,.3)}
.room-list{display:flex;flex-direction:column;gap:.4rem;margin:.35rem 0}
.room-btn{
  min-height:var(--touch);border-radius:14px;padding:.55rem .8rem;text-align:left;font-weight:800;
  background:rgba(0,0,0,.28);border:2px solid rgba(74,222,128,.3);
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:.35rem;
}
.room-list .empty{text-align:center;color:var(--muted);font-weight:700;padding:.5rem}
.plist{display:flex;flex-direction:column;gap:.4rem;margin:.5rem 0}
.plist .p{
  padding:.55rem .7rem;border-radius:12px;font-weight:800;
  background:rgba(0,0,0,.25);border:2px solid rgba(255,255,255,.1);
}
.plist .p.me{border-color:var(--warn);color:var(--warn)}
#lobby-code{color:var(--warn);letter-spacing:.1em}
.ghead{
  display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:.4rem;
  background:var(--panel);padding:.55rem .7rem;border-radius:14px;font-weight:900;
}
.scores{display:flex;gap:1rem}
.sc.black{color:#e2e8f0}.sc.white{color:#94a3b8}
#turn-label{
  color:var(--warn);
  min-height:48px;
  padding:.28rem .75rem;
  border-radius:12px;
  display:inline-flex;
  align-items:center;
  font-weight:900;
  border:2px solid rgba(251,191,36,.5);
  background:rgba(251,191,36,.16);
}
#turn-label.is-black{
  color:#f8fafc;background:rgba(15,23,42,.78);border-color:#94a3b8;
}
#turn-label.is-white{
  color:#1e293b;background:rgba(248,250,252,.9);border-color:#cbd5e1;
}
html.elder-mode #turn-label{min-height:60px;font-size:1.15rem}
.toast{min-height:1.25em;text-align:center;color:var(--good);font-weight:800}
.room-tag{text-align:center;color:var(--muted);font-weight:700;font-size:.9rem}
.board-wrap{flex:1;min-height:0;
  background:
    repeating-linear-gradient(90deg,rgba(0,0,0,.28) 0 2px,transparent 2px 10px),
    repeating-linear-gradient(0deg,rgba(255,255,255,.12) 0 2px,transparent 2px 11px),
    linear-gradient(160deg,#187a38,#062e14);
  border-radius:16px;padding:.4rem;
  border:5px solid rgba(251,191,36,.55);
  box-shadow:inset 0 0 28px rgba(0,0,0,.5);
}
.board{
  display:grid;grid-template-columns:repeat(8,1fr);grid-template-rows:repeat(8,1fr);
  gap:.14rem;aspect-ratio:1;
}
.cell{
  background:rgba(0,0,0,.36);border-radius:8px;border:3px solid rgba(255,255,255,.22);
  display:flex;align-items:center;justify-content:center;min-height:0;position:relative;
}
.cell.legal{box-shadow:inset 0 0 0 5px rgba(74,222,128,1);background:rgba(74,222,128,.18)}
.cell.legal::after{
  content:"";width:48%;height:48%;border-radius:50%;background:rgba(74,222,128,.98);
  box-shadow:0 0 0 3px rgba(255,255,255,.75);
}
html.elder-mode .cell.legal::after{width:56%;height:56%}
.disc{
  width:96%;height:96%;border-radius:50%;
  box-shadow:0 5px 0 rgba(0,0,0,.5),0 10px 14px rgba(0,0,0,.36);
}
.disc.b{background:radial-gradient(circle at 30% 28%,#cbd5e1,#020617 58%);border:3px solid #020617}
.disc.w{background:radial-gradient(circle at 30% 28%,#fff,#f8fafc 45%,#e2e8f0);border:4px solid #f1f5f9}
.legend{
  display:flex;justify-content:space-between;flex-wrap:wrap;gap:.4rem;
  font-weight:700;color:var(--muted);font-size:.9rem;
}
.actions{display:flex;gap:.4rem;flex-shrink:0}
.actions .btn,.actions button{min-height:58px;font-size:1.05rem;font-weight:800}
.overlay{
  position:fixed;inset:0;background:rgba(2,12,8,.8);
  display:flex;align-items:center;justify-content:center;padding:1rem;z-index:30;
}
.card{
  background:var(--panel);border-radius:18px;padding:1.1rem;width:min(420px,100%);
  border:2px solid rgba(74,222,128,.35);
}
.card h2{text-align:center;color:var(--warn);margin-bottom:.5rem}
.card ol{margin:.4rem 0 1rem 1.15rem;font-weight:700;line-height:1.65;color:#bbf7d0}