/* OpeningMatrix study shell — top tabs, no sidebar / streak / changelog. */

html[data-product="openingmatrix"] {
  --sidebar-w: 0px;
  --sidebar-w-collapsed: 0px;
  --om-topbar-h: 72px;
}

html[data-product="openingmatrix"] body.om-study-shell {
  padding-top: var(--om-topbar-h);
}

html[data-product="openingmatrix"] .site-frame {
  margin-left: 0;
}

.om-topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 130;
  display: flex;
  align-items: center;
  gap: 1rem;
  min-height: var(--om-topbar-h);
  padding: 0.65rem clamp(0.85rem, 2.5vw, 1.5rem);
  border-bottom: 1px solid var(--line, rgba(255, 255, 255, 0.08));
  background:
    linear-gradient(180deg, color-mix(in srgb, var(--gold, #39ff14) 5%, transparent), transparent 70%),
    var(--bg, #0b0b0b);
  backdrop-filter: blur(10px);
}

.om-topbar-brand-stack {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.2rem;
  flex: 0 0 auto;
  min-width: 0;
}

.om-topbar-brand {
  flex: 0 0 auto;
  text-decoration: none;
  color: inherit;
}

.om-topbar-brand .brand-name {
  font-size: 1.05rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.om-topbar-brand .brand-name em {
  color: var(--gold-bright, #7cff4a);
  font-style: normal;
}

/* Family mark: OpeningMatrix → ChessTropic */
.om-family {
  display: inline-flex;
  align-items: baseline;
  gap: 0.35rem;
  margin: 0;
  padding: 0.2rem 0.55rem;
  border-radius: 999px;
  border: 1px solid color-mix(in srgb, var(--gold, #39ff14) 28%, var(--line, rgba(255, 255, 255, 0.12)));
  background: color-mix(in srgb, var(--gold, #39ff14) 12%, var(--panel, #141414));
  color: var(--text, #f4f4f0);
  text-decoration: none;
  line-height: 1.2;
  white-space: nowrap;
}

a.om-family:hover {
  border-color: color-mix(in srgb, var(--gold, #39ff14) 55%, transparent);
  background: color-mix(in srgb, var(--gold, #39ff14) 18%, var(--panel, #141414));
}

.om-family-kicker {
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted, #a7a79c);
}

.om-family-brand {
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.om-family-brand em {
  color: var(--gold-bright, #7cff4a);
  font-style: normal;
}

.om-family--sm {
  padding: 0.12rem 0.45rem;
}

.om-family--sm .om-family-kicker {
  font-size: 0.58rem;
}

.om-family--sm .om-family-brand {
  font-size: 0.72rem;
}

.om-family--lg {
  padding: 0.35rem 0.75rem;
  margin-bottom: 0.75rem;
}

.om-family--lg .om-family-kicker {
  font-size: 0.7rem;
}

.om-family--lg .om-family-brand {
  font-size: 0.95rem;
}

.om-family-line {
  margin: 0.65rem 0 0;
  max-width: 36rem;
  color: var(--muted, #a7a79c);
  font-size: 0.95rem;
  line-height: 1.45;
}

.om-family-line a {
  color: var(--gold-bright, #7cff4a);
  font-weight: 650;
  text-decoration: none;
}

.om-family-line a:hover {
  text-decoration: underline;
}

.footer-brand-block .om-family-line {
  margin-top: 0.65rem;
  font-size: 0.95rem;
  line-height: 1.55;
  max-width: 34ch;
}

.om-tabs {
  display: flex;
  flex: 1 1 auto;
  align-items: center;
  justify-content: center;
  gap: 0.25rem;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: none;
}

.om-tabs::-webkit-scrollbar {
  display: none;
}

.om-tab {
  flex: 0 0 auto;
  padding: 0.55rem 0.9rem;
  border-radius: 999px;
  border: 1px solid transparent;
  color: var(--muted, #a7a79c);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 560;
  white-space: nowrap;
  transition: color 0.15s ease, background 0.15s ease, border-color 0.15s ease;
}

.om-tab:hover {
  color: var(--text, #f4f4f0);
  background: color-mix(in srgb, var(--gold, #39ff14) 8%, transparent);
}

.om-tab.is-active {
  color: var(--ink, #0a0a0a);
  background: var(--gold, #39ff14);
  border-color: color-mix(in srgb, var(--gold, #39ff14) 70%, #fff);
}

.om-topbar-actions {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 0.55rem;
  margin-left: auto;
}

.om-topbar-link {
  color: var(--muted, #a7a79c);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 550;
  padding: 0.35rem 0.45rem;
}

.om-topbar-link:hover {
  color: var(--text, #f4f4f0);
}

.om-topbar-cta {
  padding: 0.45rem 0.85rem !important;
  font-size: 0.88rem !important;
  border-radius: 999px !important;
  text-decoration: none;
}

.om-account-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-height: 2.4rem;
  padding: 0.2rem 0.75rem 0.2rem 0.25rem;
  border-radius: 999px;
  border: 1px solid color-mix(in srgb, var(--line, rgba(255, 255, 255, 0.12)) 85%, var(--gold, #39ff14));
  background: color-mix(in srgb, var(--panel, #141414) 88%, transparent);
  color: var(--text, #f4f4f0);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 620;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.om-account-btn:hover,
.om-account-btn.is-active {
  border-color: color-mix(in srgb, var(--gold, #39ff14) 45%, var(--line, rgba(255, 255, 255, 0.12)));
  background: color-mix(in srgb, var(--gold, #39ff14) 12%, var(--panel, #141414));
}

.om-account-btn-avatar {
  width: 1.85rem;
  height: 1.85rem;
  border-radius: 999px;
  display: inline-grid;
  place-items: center;
  overflow: hidden;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--ink, #0a0a0a);
  background: linear-gradient(145deg, var(--gold-bright, #7cff4a), var(--gold, #39ff14));
}

.om-account-btn-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

@media (max-width: 900px) {
  .om-topbar {
    flex-wrap: wrap;
    min-height: 0;
    padding-bottom: 0.55rem;
  }

  .om-tabs {
    order: 3;
    flex: 1 1 100%;
    justify-content: flex-start;
    padding-bottom: 0.15rem;
  }

  html[data-product="openingmatrix"] body.om-study-shell {
    padding-top: 6.75rem;
  }

  .om-account-btn-label {
    display: none;
  }
}