/* 顶部导航栏 */
.top-nav {
  background: var(--md3-surface);
  border-bottom: 1px solid var(--md3-outline-variant);
  padding: var(--space-3) var(--space-4);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--elevation-1);
}

.nav-left {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--md3-primary);
}

.nav-title {
  font-size: 18px;
  font-weight: 700;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.nav-user {
  font-size: 14px;
  font-weight: 500;
  color: var(--md3-on-surface);
}

.nav-role {
  font-size: 12px;
  padding: 2px 8px;
  border-radius: 12px;
  background: var(--md3-primary-container);
  color: var(--md3-on-primary-container);
  font-weight: 500;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  background: var(--md3-surface-variant);
  color: var(--md3-on-surface);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: background 0.2s;
}

.nav-link:hover {
  background: var(--md3-surface-container-high);
}

.nav-btn {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  background: transparent;
  border: 1.5px solid var(--md3-outline);
  color: var(--md3-on-surface);
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.2s;
}

.nav-btn:hover {
  background: var(--md3-surface-variant);
  border-color: var(--md3-on-surface-variant);
}

/* 响应式 */
@media (max-width: 768px) {
  .nav-title {
    display: none;
  }

  .nav-role {
    display: none;
  }

  .nav-link span,
  .nav-btn span {
    display: none;
  }

  .nav-link,
  .nav-btn {
    padding: 8px;
    min-width: 40px;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .top-nav {
    padding: 8px 12px;
  }

  .nav-logo svg,
  .nav-logo i {
    width: 20px !important;
    height: 20px !important;
  }

  .nav-link i,
  .nav-link svg,
  .nav-btn i,
  .nav-btn svg {
    width: 18px !important;
    height: 18px !important;
  }
}