/* The personal site and each learning tool use this shared header. */
.masthead { position: relative; z-index: 40; border-bottom: 1px solid #dbe2e5; background: #fff; font-family: Arial, "Helvetica Neue", sans-serif; line-height: 1.5; }
.masthead [hidden] { display: none !important; }
.masthead .site-header-inner { box-sizing: border-box; max-width: 1120px; margin: auto; padding: 24px 32px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.masthead .site-brand { color: #203541 !important; font-size: 1.125rem; font-weight: 600; text-decoration: none; white-space: nowrap; }
.site-navigation { font-size: 1rem; }
.site-navigation .site-links { display: flex; align-items: center; gap: 24px; list-style: none; margin: 0; padding: 0; }
.site-navigation .site-links li { margin: 0; }
.site-navigation .site-links a { box-sizing: border-box; display: block; padding: 10px 0; min-height: 44px; color: #263b46; font-size: 1rem; font-weight: 400; text-decoration: none; text-underline-offset: .2em; }
.site-navigation .site-links a:hover,.site-navigation .site-links a[aria-current="page"] { color: #176b72; text-decoration: underline; }
.site-navigation .site-menu-toggle { min-height: 44px; padding: 8px 16px; border: 1px solid #7d929b; border-radius: 3px; background: #fff; color: #263b46; font: 400 1rem/1.5 Arial, "Helvetica Neue", sans-serif; align-items: center; gap: 8px; cursor: pointer; }
.site-menu-icon { display: inline-block; width: 16px; height: 12px; border-block: 1px solid currentColor; position: relative; }
.site-menu-icon::after { content: ""; height: 1px; width: 16px; background: currentColor; position: absolute; top: 4px; left: 0; }
.site-navigation .learning-menu { position: relative; margin: 0; border: 0; padding: 0; }
.site-navigation .learning-menu>summary { box-sizing: border-box; display: flex; align-items: center; gap: 8px; min-height: 44px; padding: 10px 0; margin: 0; color: #263b46; font: 400 1rem/1.5 Arial, "Helvetica Neue", sans-serif; cursor: pointer; list-style: none; }
.learning-menu>summary::-webkit-details-marker { display: none; }
.learning-menu>summary::after { content: ""; width: 6px; height: 6px; border-right: 1px solid currentColor; border-bottom: 1px solid currentColor; transform: rotate(45deg); margin-top: -3px; }
.learning-menu[open]>summary::after { transform: rotate(225deg); margin-top: 3px; }
.site-navigation .learning-menu.is-active>summary,.site-navigation .learning-menu[open]>summary,.site-navigation .learning-menu>summary:hover { color: #176b72; }
.site-navigation .learning-menu-links { box-sizing: border-box; position: absolute; top: calc(100% + 8px); right: 0; z-index: 45; min-width: 240px; margin: 0; padding: 8px 16px; list-style: none; border: 1px solid #dbe2e5; border-radius: 3px; background: #fff; box-shadow: 0 4px 12px #20354112; }
.site-navigation .learning-menu-links a { white-space: nowrap; }
.site-navigation .learning-menu-overview { border-top: 1px solid #dbe2e5; margin-top: 4px !important; padding-top: 4px; }
.masthead a:focus-visible,.masthead button:focus-visible,.masthead summary:focus-visible { outline: 3px solid #176b72; outline-offset: 3px; }
body>.skip:focus { z-index: 1000; }
@media (max-width: 960px) {
  .masthead .site-header-inner { flex-wrap: wrap; padding: 16px 24px; }
  .site-navigation { margin-left: auto; }
  .site-navigation .site-menu-toggle { display: flex; }
  .site-navigation .site-links { position: absolute; top: 100%; left: 0; right: 0; z-index: 40; flex-direction: column; align-items: stretch; gap: 0; padding: 8px 24px 16px; border-bottom: 1px solid #dbe2e5; background: #fff; }
  .site-navigation .learning-menu-links { position: static; min-width: 0; margin: 4px 0; padding: 0 16px; border: 0; border-left: 2px solid #dbe2e5; border-radius: 0; box-shadow: none; }
  .site-navigation .learning-menu-links a { white-space: normal; }
  .no-js .site-navigation { width: 100%; }
  .no-js .site-navigation .site-links { position: static; padding: 0; border-bottom: 0; }
}
@media (max-width: 640px) {
  .masthead .site-header-inner { padding-left: 16px; padding-right: 16px; gap: 16px; }
  .site-navigation .site-links { padding-left: 16px; padding-right: 16px; }
}
@media print { .masthead { display: none !important; } }