body.academy-tool-shell {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(circle at top left, rgba(56, 189, 248, 0.1), transparent 34%),
    radial-gradient(circle at 82% 16%, rgba(251, 191, 36, 0.08), transparent 24%),
    linear-gradient(180deg, #08101d 0%, #0b1120 44%, #09121f 100%);
}

body.academy-tool-shell > * {
  position: relative;
  z-index: 1;
}

.academy-shell-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin: 10px 12px 12px;
  padding: 14px 18px;
  border-radius: 18px;
  border: 1px solid rgba(148, 163, 184, 0.14);
  background: linear-gradient(180deg, rgba(19, 29, 46, 0.94), rgba(12, 20, 34, 0.94));
  backdrop-filter: blur(18px);
  box-shadow: 0 12px 28px rgba(2, 8, 23, 0.28);
}

.academy-shell-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.academy-shell-mark {
  width: 40px;
  height: 40px;
  border-radius: 14px;
  background:
    url('/img/logo.svg') center / 24px 24px no-repeat,
    linear-gradient(135deg, rgba(56, 189, 248, 0.18), rgba(251, 191, 36, 0.18));
  border: 1px solid rgba(56, 189, 248, 0.24);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
  flex-shrink: 0;
}

.academy-shell-copy {
  display: grid;
  gap: 3px;
}

.academy-shell-title {
  font-family: 'Orbitron', sans-serif;
  font-size: 0.84rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.academy-shell-subtitle {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.64rem;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.academy-shell-links {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.academy-shell-links a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  border: 1px solid rgba(56, 189, 248, 0.22);
  background: rgba(56, 189, 248, 0.08);
  color: var(--accent);
  text-decoration: none;
  font-family: 'JetBrains Mono', monospace;
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.academy-shell-links a:hover {
  color: var(--text-primary);
  border-color: rgba(125, 211, 252, 0.38);
  background: rgba(56, 189, 248, 0.14);
}

.academy-shell-links a.current {
  border-color: rgba(251, 191, 36, 0.24);
  background: rgba(251, 191, 36, 0.08);
  color: var(--warning);
}

body.academy-tool-shell #root {
  flex: 1;
  min-height: 0;
}

@media (max-width: 720px) {
  .academy-shell-bar {
    margin-left: 10px;
    margin-right: 10px;
    padding: 12px 14px;
  }
}