.site-header {
  background: #1f2a36;
  box-shadow: 0 0 0 100vmax #1f2a36;
  clip-path: inset(0 -100vmax);
  padding: 22px 0;
  border-bottom: 0;
}
.site-title,
.menu-links a,
.menu-toggle { color: #fff; }
.menu-links a:hover { color: #cfe0f0; }

.site-title:hover { color: #fff; opacity: .85; text-decoration: none; }

.post-meta { display: flex; align-items: center; flex-wrap: wrap; gap: 10px; margin: 8px 0 18px; }
.post-meta time { line-height: 1; }
.post-meta .post-categories { margin: 0; }



.sidebar-categories ul { display: flex; flex-direction: column; align-items: flex-start; gap: 8px; }
.sidebar-categories li { padding: 0; border-bottom: 0; }
.sidebar-categories li a {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 5px 6px 5px 14px;
  background: #dbeaf3; color: #1f6f9f;
  border-radius: 999px; text-decoration: none;
}
.sidebar-categories li a:hover { background: #c9e0ee; color: #155a85; text-decoration: none; }
.category-count {
  min-width: 2.2em; padding: 1px 8px;
  background: #0f6aa5; color: #fff;
  border-radius: 999px; font-size: .75rem; text-align: center; line-height: 1.6;
}

.recent-date { margin-left: 6px; color: var(--muted); font-size: .7rem; white-space: nowrap; }



/* hamburger menu */
.menu-toggle { display: none; }

@media (max-width: 760px) {
  .site-header {
    position: relative;
    box-shadow: none;
    clip-path: none;
    margin: 0 -22px 30px;
    padding: 18px 22px;
  }
  .menu-toggle {
    display: inline-flex; align-items: center; justify-content: center;
    width: 40px; height: 40px; padding: 0;
    background: transparent; border: 1px solid rgba(255,255,255,.35); border-radius: 4px;
    cursor: pointer;
  }
  .menu-icon,
  .menu-icon::before,
  .menu-icon::after {
    display: block; width: 18px; height: 2px; background: #fff; position: relative;
  }
  .menu-icon::before,
  .menu-icon::after { content: ""; position: absolute; left: 0; }
  .menu-icon::before { top: -6px; }
  .menu-icon::after { top: 6px; }

  .menu-links {
    display: none;
    position: absolute; z-index: 10; top: 100%; right: 0; left: 0;
    flex-direction: column; gap: 0;
    padding: 6px 22px 12px;
    background: #1f2a36; border: 0;
  }
  .site-header.is-menu-open .menu-links { display: flex; }
  .menu-links a { display: block; padding: 11px 0; color: #fff; border-top: 1px solid rgba(255,255,255,.12); }
}


/* back to top */
.back-to-top {
  position: fixed; right: 20px; bottom: 20px; z-index: 20;
  width: 44px; height: 44px;
  border: 0; border-radius: 50%;
  background: #1f2a36; color: #fff;
  font-size: 1.1rem; line-height: 1; cursor: pointer;
  box-shadow: 0 2px 8px rgba(0,0,0,.2);
  opacity: 0; visibility: hidden;
  transition: opacity .2s, visibility .2s;
}
.back-to-top.is-visible { opacity: .85; visibility: visible; }
.back-to-top:hover { opacity: 1; }