:root {
  color-scheme: dark;
  --bg: #101014;
  --panel: #191820;
  --line: #302c3b;
  --text: #f3f0ff;
  --muted: #a39bb8;
  --purple: #a78bfa;
  --cell: 22.4px;
  --depth: 8px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 14px/1.45 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  min-height: 100vh;
}

.shell {
  max-width: 650px;
  margin: 0 auto;
  padding: 36px 18px 28px;
}

header {
  text-align: center;
  margin-bottom: 24px;
}

.brand-title {
  margin: 0;
  color: #b69aff;
  font-family: "Courier New", monospace;
  font-size: clamp(38px, 8vw, 58px);
  font-weight: 1000;
  letter-spacing: .06em;
  line-height: 1;
  text-shadow: 3px 3px 0 #6249a6, 6px 6px 0 #34264f;
  -webkit-text-stroke: .6px #e0d3ff;
}

.tagline {
  margin: 18px auto 0;
  max-width: 420px;
  color: #c4bdd4;
  font-size: 14px;
  line-height: 1.55;
}

.tagline strong {
  color: #e1d5ff;
  font-weight: 650;
}

.layout {
  display: grid;
  grid-template-columns: minmax(180px, 240px) minmax(0, 1fr);
  align-items: start;
  gap: 22px;
}

.concept {
  align-self: center;
  width: 100%;
  max-width: 240px;
}

.concept img {
  display: block;
  width: 100%;
  height: auto;
  max-height: 330px;
  object-fit: contain;
  border: 1px solid #302b3a;
  border-radius: 4px;
  background: #e8e2d9;
}

.concept p {
  margin: 12px 0 0;
  color: #c4bdd4;
  font-size: 13px;
  line-height: 1.55;
  text-align: left;
}

.trainer-main {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  min-width: 0;
  width: 100%;
}

.play-panel {
  width: 100%;
}

.controls {
  width: 100%;
}

@media (max-width: 720px) {
  .layout {
    grid-template-columns: minmax(130px, 190px) minmax(0, 1fr);
    gap: 14px;
  }
  .concept img {
    max-height: 280px;
  }
}

@media (max-width: 560px) {
  .layout {
    grid-template-columns: 1fr;
    gap: 18px;
  }
  .concept {
    max-width: 220px;
    margin: 0 auto;
  }
  .concept p {
    text-align: center;
  }
  .trainer-main {
    width: 100%;
  }
  .controls {
    max-width: 480px;
  }
}

.toast {
  position: fixed;
  left: 50%;
  bottom: 18px;
  transform: translate(-50%, 20px);
  opacity: 0;
  pointer-events: none;
  background: #211d2b;
  border: 1px solid #51446e;
  color: #f2eaff;
  padding: 8px 12px;
  border-radius: 4px;
  font-size: 12px;
  transition: .2s;
}

.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

.hidden-settings {
  display: none !important;
}

@media (max-width: 520px) {
  :root {
    --cell: 25px;
  }
  .shell {
    padding: 28px 10px 20px;
  }
  .controls {
    grid-template-columns: 1fr;
  }
  .key-setting {
    grid-column: auto;
  }
  .board-wrap {
    padding: 6px;
  }
  .brand-title {
    font-size: 42px;
  }
  .tagline {
    font-size: 13px;
    margin-top: 15px;
  }
}