.app-shell {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-around;
  padding: 20px 28px;
  position: sticky;
  top: 0;
  backdrop-filter: blur(18px);
  background: rgba(15, 23, 42, 0.8);
  border-bottom: 1px solid var(--fx-blue-veil);
  z-index: 10;
}

.logo img {
  width: 56px;
  height: 56px;
}

.title {
  margin: 0;
  font-size: 1.75rem;
  letter-spacing: 0.02em;
}

.menu-btn {
  background: transparent;
  border: 1px solid var(--fx-blue-veil);
  border-radius: 999px;
  padding: 8px 14px;
  color: var(--mist-050);
  font-size: 20px;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition);
}

.menu-btn:hover,
.menu-btn:focus-visible {
  background: rgba(148, 163, 184, 0.12);
  border-color: var(--fx-white-soft);
}

.drawer {
  display: none;
  position: fixed;
  top: 70px;
  right: 24px;
  padding: 10px 14px;
  min-width: 230px;
  background: color-mix(in srgb, var(--neutral-900) 92%, transparent);
  border: 1px solid var(--fx-blue-veil);
  border-radius: 14px;
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.35);
  z-index: 40;
}

.drawer a {
  display: block;
  color: var(--mist-050);
  text-decoration: none;
  padding: 8px 6px;
  border-radius: 8px;
  font-weight: 500;
}

.drawer a:hover {
  background: rgba(148, 163, 184, 0.18);
}

.app-main {
  flex: 1;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 32px 60px;
}

.orientation-hint {
  display: none;
  margin: 16px auto 0;
  text-align: center;
  color: var(--neutral-200);
  font-size: 0.95rem;
  max-width: 680px;
}

.panel-grid {
  display: grid;
  gap: 28px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  grid-template-areas:
    "instructions practice templates"
    ". . metronome";
}

.panel {
  max-height: 400px;
  background: var(--neutral-300);
  border: 1px solid var(--fx-blue-veil);
  border-radius: 24px;
  box-shadow: var(--fx-shadow-subtle);
  padding: 8px;
  display: flex;
  flex-direction: column;
  transition: border-color var(--transition), transform var(--transition);
}

.panel:hover {
  border-color: var(--fx-white-soft);
  transform: translateY(-2px);
}

.panel--instructions {
  grid-area: instructions;
  max-height: 400px;
  overflow: hidden;
}

.panel--templates {
  grid-area: templates;
  height: 240px;
  overflow: hidden;
  margin-bottom: 8px;
}

.panel--practice {
  grid-area: practice;
  height: 400px;
  max-height: 400px;
}

.panel--metronome {
  grid-area: metronome;
  height: 200px;
  max-height: 200px;
  overflow: hidden;
  padding: 16px;
  gap: 12px;
  height: min-content;
}

.panel-header {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.panel-header h2 {
  margin: 0;
  font-size: 1.35rem;
}

.panel-header--practice {
  flex-direction: row;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.header-frame {
  display: flex;
  justify-content: space-between;
  width: 100%;
  padding-right: 8px;
}

.header-frame button {
  background-color: var(--red-200) !important;
  border-radius: 8px;
}

.panel-header__actions--practice {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
  margin-left: auto;
}

.panel-header--practice .playback-controls {
  margin-bottom: 0;
}

.panel-header--practice .btn.small {
  line-height: 1.1;
}

.panel-header--metronome {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-direction: row;
}

.panel-header--metronome .panel-header__info {
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.panel-header--metronome .btn {
  flex-shrink: 0;
}

.panel-header--metronome .btn.is-running {
  background: rgba(248, 113, 113, 0.15);
  border-color: var(--red-200);
  color: var(--red-200);
}

.panel-subtitle {
  margin: 0;
  color: var(--neutral-200);
  font-size: 0.95rem;
}

.panel-content {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.panel--instructions,
.panel--templates,
.panel--practice,
.panel--metronome {
  display: flex;
  flex-direction: column;
}

.panel--instructions .panel-content,
.panel--templates .panel-content {
  flex: 1;
  overflow: auto;
}

.panel--practice .panel-content,
.panel--metronome .panel-content {
  flex: 1;
  overflow: auto;
}



.app-footer {
  padding: 24px;
  text-align: center;
  color: var(--neutral-200);
  border-top: 1px solid var(--fx-blue-veil);
  background: rgba(15, 23, 42, 0.85);
}


@media (max-width: 960px) {
  .panel-grid {
    grid-template-columns: 1fr;
    grid-template-areas:
      "instructions"
      "templates"
      "metronome"
      "practice";
  }

  .panel--instructions,
  .panel--templates,
  .panel--practice,
  .panel--metronome {
    height: auto;
    max-height: none;
  }

  .panel--instructions,
  .panel--templates {
    overflow: visible;
  }

  .orientation-hint {
    display: block;
  }
}

@media (max-width: 768px) {
  .app-header {
    padding: 16px 20px;
  }

  .menu-btn {
    display: none;
  }

  .app-main {
    padding: 28px 20px 40px;
  }

  .panel {
    padding: 24px;
  }

}

@media (max-width: 480px) {
  .panel-grid {
    gap: 20px;
  }

  .panel {
    gap: 16px;
    padding: 20px;
  }

  .cta-row {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    text-align: center;
  }

  .recording-primary,
  .recording-secondary {
    flex-direction: column;
    align-items: stretch;
  }

  .recording-secondary input {
    width: 100%;
  }

  .key.black {
    right: -24%;
  }
}