/* Little Leaf-inspired palette shared by course and classroom pages. */
:root { color: #283c33; background: #f8f7f2; font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif; }
body, .series-home { background: #f8f7f2; color: #283c33; }
button, input, select, textarea { font-family: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible { outline: 3px solid #d5ab74; outline-offset: 3px; }
.series-shell { padding-top: 76px; }
.series-hero { margin-bottom: 48px; }
.series-kicker { color: #638f6c; letter-spacing: .16em; }
.series-hero h1, .series-card h2, .course-card h3 { color: #283c33; }
.series-hero > p:last-child, .series-card p, .course-card span { color: #7b887f; }
.series-card, .course-card { border-color: #e7eae2; border-radius: 20px; box-shadow: 0 12px 35px #263d3210; }
.series-card:hover, .series-card:focus-visible, .course-card:hover, .course-card:focus-visible { transform: translateY(-4px); box-shadow: 0 18px 36px #263d3220; }
.series-card:focus-visible, .course-card:focus-visible { outline: 3px solid #d5ab74; }
.series-code, .series-card-e .series-code, .series-card-f .series-code { background: #edf5ef; color: #315c43; }
.series-card .series-age, .series-enter, .back-home, .course-card p { color: #315c43; }
.page-shell { width: min(1380px, calc(100% - 48px)); margin: 28px auto; }
.page-header { padding: 18px 22px; border: 1px solid #e7eae2; border-radius: 20px; background: #fff; box-shadow: 0 12px 35px #263d3210; }
.d-page-header h1 { color: #283c33; }
.d-back-link, .d-series-label { background: #edf5ef; color: #315c43; box-shadow: none; }
select, .lesson-range-control { border-color: #e0e7df; border-radius: 12px; color: #526b5a; }
.lesson-status { border-radius: 14px; background: #edf5ef; color: #315c43; }
.progress-track { background: #dfe9df; }
.progress-track i { background: #638f6c; }
.lesson-range-control input { accent-color: #638f6c; }
.lesson-range-control output { color: #315c43; }
.button { border-radius: 12px; }
.start { background: #315c43; }
.resume { background: #bd8551; }
.stop { background: #b96f60; }
.pdf-card, .visual-card, .reading-card, .transcript-card { border: 1px solid #e7eae2; border-radius: 20px; background: #fff; box-shadow: 0 12px 35px #263d3210; }
.pdf-card { padding: 20px; }
.pdf-card strong, .pdf-page-control, .pdf-toolbar > output { color: #526b5a; }
.pdf-toolbar button { border-color: #e0e7df; border-radius: 10px; color: #315c43; }
.pdf-toolbar button:hover { border-color: #80a184; color: #244c35; }
.pdf-page-viewport { border-radius: 14px; background: #f3f5ef; }
.question-card { border: 1px solid #dce9dc; border-radius: 18px; background: #edf5ef; color: #283c33; box-shadow: none; }
.transcript-card { padding: 20px; }
h2 { color: #315c43; }
.d-word-cards-tab { border-color: #eadcc5; background: #fff7e9; color: #956c3f; }
.d-word-cards-tab b { background: #c69360; }
@media (max-width: 760px) {
  .series-shell { padding-top: 54px; }
  .page-shell { width: calc(100% - 24px); margin: 12px auto; }
  .page-header { padding: 14px; border-radius: 16px; }
  .pdf-card { padding: 12px; }
}

/* Navigation follows the student classroom header in the prototype. */
.site-header { display: flex; align-items: center; justify-content: space-between; gap: 18px; min-height: 86px; padding: 16px 26px; border: 1px solid #e7eae2; border-radius: 20px; background: #fff; box-shadow: 0 12px 35px #263d3210; }
.site-header-left { display: flex; align-items: center; min-width: 0; }
.site-brand { display: inline-flex; align-items: center; flex-shrink: 0; gap: 10px; color: #283c33; font-size: 21px; font-weight: 800; letter-spacing: 1px; text-decoration: none; }
.site-brand-mark { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 13px; background: #315c43; color: #fff; }
.site-brand-mark svg, .site-courses svg { width: 20px; height: 20px; flex-shrink: 0; }
.site-brand small { display: block; margin-top: 2px; color: #7b887f; font-size: 10px; font-weight: 500; letter-spacing: 3px; }
.site-title { min-width: 0; margin-left: 26px; padding-left: 26px; border-left: 1px solid #e7eae2; }
.site-title b { display: block; color: #283c33; font-size: 15px; }
.site-title p { margin: 5px 0 0; color: #7b887f; font-size: 11px; }
.site-navigation { display: flex; align-items: center; flex-shrink: 0; gap: 18px; }
.site-courses { display: inline-flex; align-items: center; justify-content: center; gap: 8px; min-height: 44px; padding: 10px 16px; border: 1px solid #e7eae2; border-radius: 12px; background: #fff; color: #315c43; font-size: 14px; font-weight: 650; text-decoration: none; }
.site-courses:hover { background: #edf5ef; }
.site-avatar { display: grid; place-items: center; width: 38px; height: 38px; border-radius: 50%; background: #eddbc4; color: #735f49; font-size: 13px; font-weight: 700; }
.series-shell { padding-top: 28px; }
.series-shell .site-header { margin-bottom: 58px; }
.series-course-shell { max-width: 1160px; }
.series-course-shell .back-home { margin-bottom: 40px; }
.page-shell .site-header { margin-bottom: 18px; }
@media (max-width: 760px) {
  .series-shell { padding-top: 12px; }
  .site-header { min-height: 75px; padding: 14px 16px; border-radius: 16px; }
  .site-brand { font-size: 18px; }
  .site-title { display: none; }
  .site-navigation { gap: 9px; }
  .site-avatar { display: none; }
  .site-courses { padding: 10px 12px; font-size: 12px; }
  .series-shell .site-header { margin-bottom: 36px; }
  .series-course-shell .back-home { margin-bottom: 30px; }
}

.site-account { position: relative; flex-shrink: 0; }
.site-avatar { list-style: none; cursor: pointer; user-select: none; }
.site-avatar::-webkit-details-marker { display: none; }
.site-avatar:focus-visible { outline: 3px solid #d5ab74; outline-offset: 3px; }
.site-account-menu { position: absolute; z-index: 20; top: calc(100% + 8px); right: 0; min-width: 120px; padding: 6px; border: 1px solid #e7eae2; border-radius: 12px; background: #fff; box-shadow: 0 12px 35px #263d3220; }
.site-logout { display: block; padding: 10px 12px; border-radius: 8px; color: #315c43; font-size: 13px; text-decoration: none; white-space: nowrap; }
.site-logout:hover, .site-logout:focus-visible { background: #edf5ef; }
@media (max-width: 760px) { .site-avatar { display: grid; } }