html,
   body {
       margin: 0;
       padding: 0;
       background: radial-gradient(circle at top, #1a2233 0%, #0d1118 60%, #090c12 100%);
       color: #e8ecf3;
       font-family: Arial, Helvetica, sans-serif;
       overflow: hidden
   }

   #app {
       width: 100vw;
       height: 100vh;
       display: flex;
       align-items: center;
       justify-content: center;
       gap: 18px;
       padding: 0 18px;
       box-sizing: border-box
   }

   #gameWrap {
       position: relative;
       width: 960px;
       height: 600px;
       flex: 0 0 auto
   }

   #game {
       width: 960px;
       height: 600px;
       display: flex;
       align-items: center;
       justify-content: center
   }

   #ui {
       position: absolute;
       top: 12px;
       left: 50%;
       transform: translateX(-50%);
       z-index: 30;
       display: flex;
       gap: 12px;
       align-items: center;
       background: rgba(11, 15, 22, .82);
       border: 1px solid rgba(80, 100, 130, .5);
       border-radius: 14px;
       padding: 10px 14px;
       box-shadow: 0 12px 30px rgba(0, 0, 0, .35)
   }

   #songPanel {
       width: 280px;
       height: 560px;
       background: rgba(11, 15, 22, .9);
       border: 1px solid rgba(80, 100, 130, .5);
       border-radius: 16px;
       box-shadow: 0 12px 30px rgba(0, 0, 0, .35);
       padding: 16px;
       box-sizing: border-box;
       overflow: auto
   }

   #songPanel h3 {
       margin: 0 0 8px 0;
       font-size: 22px;
       color: #f6f8fc
   }

   #songPanel p {
       margin: 0 0 12px 0;
       font-size: 13px;
       color: #9fb0c9;
       line-height: 1.35
   }

   .button-col {
       display: flex;
       flex-direction: column;
       gap: 10px
   }

   .song-btn {
       width: 100%;
       text-align: left;
       background: linear-gradient(180deg, #202b3c 0%, #161d29 100%);
       border: 1px solid #45536b;
       color: #eef3fb;
       padding: 10px 12px;
       font-size: 13px;
       font-weight: bold;
       border-radius: 10px;
       cursor: pointer
   }

   .song-btn small {
       display: block;
       font-size: 11px;
       color: #a9b7cf;
       font-weight: normal;
       margin-top: 4px
   }

   button {
       background: linear-gradient(180deg, #202b3c 0%, #161d29 100%);
       border: 1px solid #45536b;
       color: #eef3fb;
       padding: 9px 12px;
       font-size: 13px;
       font-weight: bold;
       border-radius: 8px;
       cursor: pointer
   }

   button.primary {
       background: linear-gradient(180deg, #ff6b70 0%, #e64950 100%);
       border-color: #ff8d91
   }

   input[type=range] {
       width: 140px
   }

   .readout {
       min-width: 48px;
       text-align: center;
       color: #ffd166;
       font-weight: bold;
       font-size: 13px
   }

   canvas {
       box-shadow: 0 22px 60px rgba(0, 0, 0, .45);
       border-radius: 16px
   }