.global-course-nav {
  position: relative;
  z-index: 200;
  flex: 0 0 auto;
  color: #182536;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", system-ui, sans-serif;
}

course-header { display: block; }

.lesson-course-controls {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 7px;
}

.lesson-sequence-nav {
  display: flex;
  align-items: center;
  gap: 7px;
}

.lesson-sequence-link {
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 7px 11px;
  border: 1px solid #dfe5e8;
  border-radius: 999px;
  background: #fff;
  color: #10233f !important;
  font-size: 12px;
  font-weight: 800;
  line-height: 1;
  text-decoration: none !important;
  white-space: nowrap;
}

.lesson-sequence-link:hover {
  border-color: #8da9b4;
  background: #eef4f6;
}

.lesson-sequence-link.is-disabled {
  border-color: #e8ebed;
  background: #f7f8f8;
  color: #9aa4af !important;
  cursor: not-allowed;
}

.lesson-sequence-label-short { display: none; }

.global-course-nav summary {
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 12px;
  border: 1px solid #dfe5e8;
  border-radius: 999px;
  background: #fff;
  color: #10233f;
  font-size: 12px;
  font-weight: 800;
  line-height: 1;
  list-style: none;
  cursor: pointer;
  user-select: none;
}

.global-course-nav summary::-webkit-details-marker { display: none; }
.global-course-nav summary::after { content: "⌄"; color: #607086; font-size: 13px; }
.global-course-nav[open] summary { border-color: #8da9b4; background: #eef4f6; }
.global-course-nav[open] summary::after { transform: rotate(180deg); }

.global-course-nav-menu {
  position: fixed;
  top: 62px;
  left: 50%;
  width: min(720px, calc(100vw - 32px));
  max-height: min(76vh, 720px);
  overflow: auto;
  transform: translateX(-50%);
  padding: 20px;
  border: 1px solid #dfe5e8;
  border-radius: 16px;
  background: #fff;
  box-shadow: 0 20px 55px rgba(16, 35, 63, .18);
}

.global-course-nav-home {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
  padding: 0 0 14px;
  border-bottom: 1px solid #e2e6e8;
  color: #10233f !important;
  font-size: 14px;
  font-weight: 900;
  text-decoration: none !important;
}

.global-course-nav-columns { display: grid; grid-template-columns: 1.15fr 1fr; gap: 24px; }
.global-course-nav-group h2 { margin: 0 0 9px; color: #607086; font-size: 11px; font-weight: 900; letter-spacing: .1em; line-height: 1.5; }
.global-course-nav-list { display: grid; gap: 2px; }
.global-course-nav-list a {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 8px;
  align-items: baseline;
  padding: 7px 9px;
  border-radius: 7px;
  color: #334155 !important;
  font-size: 12px;
  line-height: 1.45;
  text-decoration: none !important;
}
.global-course-nav-list a:hover { background: #f1f5f6; color: #10233f !important; }
.global-course-nav-list a[aria-current="page"] { background: #10233f; color: #fff !important; }
.global-course-nav-number { color: #286178; font-weight: 900; }
.global-course-nav-list a[aria-current="page"] .global-course-nav-number { color: #9ec2cf; }

@media (max-width: 1180px) {
  .global-course-nav-menu {
    right: 16px;
    left: 16px;
    width: auto;
    max-height: calc(100vh - 78px);
    transform: none;
  }
  .lesson-sequence-label-wide { display: none; }
  .lesson-sequence-label-short { display: inline; }
}

@media (max-width: 760px) {
  .global-course-nav-menu { padding: 16px; }
  .global-course-nav-columns { grid-template-columns: 1fr; gap: 18px; }
}

@media print {
  .global-course-nav,
  .lesson-sequence-link { display: none !important; }
}