*{margin:0;padding:0;box-sizing:border-box}
html,body{height:100%;overflow:hidden}
body{
  font-family:ui-rounded,-apple-system,"SF Pro Rounded","Segoe UI",Verdana,sans-serif;
  background:linear-gradient(#8fd0ff 0%,#cfe9ff 45%,#ffe9d6 100%);
  touch-action:none;user-select:none;-webkit-user-select:none;color:#3d4a5c;
}
#game{position:fixed;inset:0;width:100%;height:100%;display:block;z-index:2}

.sky{position:fixed;inset:0;z-index:0;opacity:0;transition:opacity 1.6s ease;pointer-events:none}
#skyA{opacity:1}
.sun{position:fixed;top:5vh;right:7vw;font-size:64px;pointer-events:none;z-index:1;
  filter:drop-shadow(0 0 26px rgba(255,210,90,.85));animation:float 6s ease-in-out infinite}
.cloud{position:fixed;font-size:52px;pointer-events:none;opacity:.9;z-index:1}
.c1{top:12vh;left:-80px;animation:drift 42s linear infinite}
.c2{top:24vh;left:-80px;font-size:38px;animation:drift 65s linear infinite;animation-delay:-30s}
@keyframes float{0%,100%{transform:translateY(0)}50%{transform:translateY(-10px)}}
@keyframes drift{from{transform:translateX(-10vw)}to{transform:translateX(115vw)}}

#hud{position:fixed;top:12px;left:0;right:0;display:flex;justify-content:space-between;
  padding:0 14px;pointer-events:none;z-index:5}
#hud div{background:rgba(255,255,255,.78);border-radius:999px;padding:8px 18px;
  font-size:20px;font-weight:800;box-shadow:0 4px 14px rgba(80,100,140,.12)}

.overlay{position:fixed;inset:0;z-index:10;display:flex;flex-direction:column;align-items:center;
  justify-content:center;gap:16px;text-align:center;padding:24px;
  background:rgba(255,255,255,.42);backdrop-filter:blur(7px);-webkit-backdrop-filter:blur(7px)}
.overlay h1{font-size:clamp(38px,7vw,68px);text-shadow:0 2px 0 #fff}
.sub{font-size:clamp(16px,2.6vw,22px);line-height:1.5;font-weight:600}
.keys{font-size:clamp(14px,2.2vw,18px);line-height:1.7;font-weight:600;opacity:.8;
  background:rgba(255,255,255,.6);border-radius:16px;padding:10px 22px}
button{
  font-family:inherit;font-size:clamp(20px,3.4vw,28px);font-weight:800;color:#fff;
  background:linear-gradient(#ff9f7e,#ff7e67);border:none;border-radius:999px;
  padding:16px 44px;cursor:pointer;box-shadow:0 8px 22px rgba(255,126,103,.45);
  transition:transform .12s ease}
button:hover{transform:scale(1.05)}
button:active{transform:scale(.96)}
.levels{display:flex;flex-direction:column;gap:12px;align-items:center}
.levels.row{flex-direction:row;flex-wrap:wrap;justify-content:center}
.lvl{display:flex;flex-direction:column;gap:2px;min-width:240px;padding:12px 36px}
.lvl span{font-size:14px;font-weight:600;opacity:.85}
.lvl[data-level="easy"]{background:linear-gradient(#7ddba3,#52c47e);box-shadow:0 8px 22px rgba(82,196,126,.4)}
.lvl[data-level="normal"]{background:linear-gradient(#7cb8f7,#5a96e8);box-shadow:0 8px 22px rgba(90,150,232,.4)}
.lvl[data-level="hard"]{background:linear-gradient(#ff9f7e,#f25c54);box-shadow:0 8px 22px rgba(242,92,84,.45)}
.ghost{background:rgba(255,255,255,.75);color:#3d4a5c;box-shadow:0 6px 16px rgba(80,100,140,.18)}
.hidden{display:none!important}

#flash{position:fixed;inset:0;z-index:8;pointer-events:none;opacity:0;transition:opacity .9s ease}
#flash.bang{transition:none;opacity:1}

/* ---- theme: normal (synthwave) ---- */
body[data-theme="normal"] .cloud{display:none}
body[data-theme="normal"] #hud div{background:rgba(16,12,40,.72);color:#7ce7ff;
  text-shadow:0 0 8px rgba(124,231,255,.6);box-shadow:0 0 14px rgba(124,231,255,.18)}
body[data-theme="normal"] .overlay{background:rgba(10,8,30,.55);color:#e8f4ff}
body[data-theme="normal"] .overlay h1{text-shadow:0 0 18px rgba(255,107,53,.8)}
body[data-theme="normal"] .keys{background:rgba(16,12,40,.6)}

/* ---- theme: hard (original neon) ---- */
body[data-theme="hard"] .cloud,body[data-theme="hard"] .sun{display:none}
body[data-theme="hard"] #hud div{background:rgba(0,0,0,.8);color:#39ff14;
  font-family:"Courier New",monospace;letter-spacing:1px;border:1px solid rgba(57,255,20,.5);
  text-shadow:0 0 8px rgba(57,255,20,.8);box-shadow:0 0 12px rgba(57,255,20,.15)}
body[data-theme="hard"] .overlay{background:rgba(0,0,0,.78);color:#39ff14;
  font-family:"Courier New",monospace}
body[data-theme="hard"] .overlay h1{color:#ff2222;text-shadow:0 0 24px rgba(255,34,34,.9)}
body[data-theme="hard"] .overlay button{background:#000;border:2px solid #39ff14;color:#39ff14;
  box-shadow:0 0 18px rgba(57,255,20,.35);font-family:inherit}
body[data-theme="hard"] .keys{background:rgba(0,0,0,.6);border:1px solid rgba(57,255,20,.3)}