:root {
  --bg-top: #fff7d4;
  --bg-bottom: #ffd8c8;
  --panel: rgba(255, 252, 246, 0.88);
  --ink: #1f2340;
  --muted: rgba(31, 35, 64, 0.72);
  --shadow: 0 18px 50px rgba(92, 60, 39, 0.16);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  font-family: "Avenir Next", "Trebuchet MS", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.95), transparent 24%),
    linear-gradient(180deg, var(--bg-top), var(--bg-bottom));
  padding: 14px;
}

.app {
  width: min(920px, 100%);
  margin: 0 auto;
  padding: 20px 14px 18px;
  border: 2px solid rgba(255, 255, 255, 0.82);
  border-radius: 28px;
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
}

.hero {
  text-align: center;
  margin-bottom: 22px;
}

.title {
  margin: 0;
  font-size: clamp(3.4rem, 12vw, 6.8rem);
  line-height: 0.92;
  letter-spacing: -0.04em;
}

.piano-wrap {
  overflow-x: auto;
  padding-bottom: 8px;
  -webkit-user-select: none;
  user-select: none;
}

.piano-wrap::-webkit-scrollbar {
  display: none;
}

.piano {
  width: 100%;
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 10px;
}

.key {
  min-height: 240px;
  border-radius: 18px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  padding: 18px 8px 14px;
  color: rgba(31, 35, 64, 0.92);
  font-weight: 800;
  box-shadow:
    inset 0 -10px 0 rgba(0, 0, 0, 0.08),
    0 8px 14px rgba(0, 0, 0, 0.12);
  cursor: pointer;
  user-select: none;
  -webkit-user-select: none;
  -webkit-touch-callout: none;
  touch-action: none;
  transition:
    transform 70ms ease,
    box-shadow 70ms ease,
    filter 70ms ease;
}

.key * {
  pointer-events: none;
  user-select: none;
  -webkit-user-select: none;
}

.key.active {
  transform: translateY(6px);
  box-shadow:
    inset 0 -4px 0 rgba(0, 0, 0, 0.1),
    0 2px 6px rgba(0, 0, 0, 0.12);
  filter: brightness(0.97);
}

.key-note {
  font-size: 1.55rem;
  line-height: 1;
}

.songs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.song-card {
  padding: 16px;
  border-radius: 22px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.78), rgba(255, 243, 233, 0.96));
}

.song-card h2 {
  margin: 0 0 10px;
  font-size: 1.1rem;
}

.song-card p {
  margin: 0 0 8px;
  line-height: 1.45;
  font-weight: 700;
}

.song-card p:last-child {
  margin-bottom: 0;
}

@media (max-width: 760px) {
  html,
  body,
  .app,
  .app * {
    -webkit-user-select: none;
    user-select: none;
  }

  body {
    padding: 10px;
  }

  .app {
    padding: 18px 12px 16px;
    border-radius: 22px;
  }

  .piano {
    width: 100%;
    grid-template-columns: repeat(7, minmax(0, 1fr));
    gap: 6px;
  }

  .key {
    min-height: 180px;
    padding: 14px 4px 12px;
    border-radius: 14px;
  }

  .key-note {
    font-size: 1.15rem;
  }

  .songs {
    grid-template-columns: 1fr;
  }
}