/* TutorPlus player: /learn/{course}/{lesson}/. App surface, Linear clean.
   Desktop: top bar, lesson column, 320px curriculum rail, course tutor panel that slides in.
   1280px and up the tutor is a third column; 901 to 1279 it replaces the rail; 900 and below rail and tutor are bottom sheets. */

body.pl-body { background: var(--paper); }
.pl { --top-h: 56px; --rail-w: 320px; --tutor-w: 380px; --tab-h: 60px;
  display: flex; flex-direction: column; height: calc(100vh - var(--admin-bar)); height: calc(100dvh - var(--admin-bar)); }

/* ------------------------------------------------------------ top bar */
.pl-top {
  flex: none; display: flex; align-items: center; gap: 12px; height: var(--top-h); padding: 0 16px 0 8px;
  border-bottom: 1px solid var(--line); background: var(--paper); position: relative; z-index: 20;
}
.pl-back {
  display: inline-flex; align-items: center; gap: 4px; height: 36px; padding: 0 10px 0 6px; border-radius: 6px;
  color: var(--text-2); font-size: 13px; font-weight: 500; white-space: nowrap;
}
.pl-back:hover { background: var(--bone); color: var(--text); }
.pl-top-sep { width: 1px; height: 20px; background: var(--line); }
.pl-brand { display: inline-flex; color: var(--ink); }
.pl-brand svg { width: 22px; height: 22px; }
.pl-top-title { flex: 1; min-width: 0; display: flex; align-items: center; gap: 10px; }
.pl-course-link { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--text); font-size: 14px; font-weight: 600; letter-spacing: -0.01em; }
.pl-course-link:hover { color: var(--cobalt); }
.pl-mode-tag { flex: none; }
.pl-top-end { flex: none; display: flex; align-items: center; gap: 12px; }
.pl-progress { display: flex; align-items: center; gap: 10px; }
.pl-progress-bar { width: 140px; }
.pl-progress-bar.is-done > span { background: var(--ok); }
.pl-progress-num { min-width: 34px; font-size: 13px; font-weight: 600; color: var(--text-2); font-variant-numeric: tabular-nums; }
.pl-tutor-toggle[aria-pressed="true"] { --bg: var(--cobalt-tint); --bd: var(--cobalt); --fg: var(--cobalt); }
.pl-avatar { display: inline-flex; border-radius: 50%; }
.pl-avatar:focus-visible { outline: var(--focus); outline-offset: 2px; }

/* ------------------------------------------------------------ enroll bar (preview) */
.pl-enrollbar {
  flex: none; display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 10px 16px 10px 20px; background: var(--cobalt); color: #fff; font-size: 13px;
}
.pl-enrollbar p { margin: 0; min-width: 0; }
.pl-enrollbar strong { font-weight: 600; }
.pl-enroll-btn { --bg: #fff; --fg: var(--cobalt); --bd: #fff; flex: none; }
.pl-enroll-btn:hover { --bg: var(--cobalt-tint); --bd: var(--cobalt-tint); --fg: var(--cobalt-deep); }

/* ------------------------------------------------------------ layout */
.pl-layout { flex: 1; min-height: 0; display: grid; grid-template-columns: minmax(0, 1fr) var(--rail-w); }
.pl-main { min-width: 0; overflow-y: auto; overscroll-behavior: contain; scroll-behavior: smooth; }
.pl-main:focus { outline: none; }
.pl-rail, .pl-tutor { min-width: 0; min-height: 0; display: flex; flex-direction: column; border-left: 1px solid var(--line); background: var(--paper); }
.pl-tutor { display: none; }
.pl.tutor-open .pl-tutor { display: flex; animation: pl-slide .22s var(--ease); }
@keyframes pl-slide { from { opacity: 0; transform: translateX(24px); } to { opacity: 1; transform: none; } }
@media (min-width: 1280px) {
  .pl.tutor-open .pl-layout { grid-template-columns: minmax(0, 1fr) var(--rail-w) var(--tutor-w); }
}
@media (min-width: 901px) and (max-width: 1279px) {
  .pl.tutor-open .pl-layout { grid-template-columns: minmax(0, 1fr) var(--tutor-w); }
  .pl.tutor-open .pl-rail { display: none; }
}
.pl-sheet-grip, .pl-tabbar, .pl-scrim { display: none; }
.pl-sheet-close { display: none; }

/* ------------------------------------------------------------ stage + reading column */
.pl-stage { padding: 24px 32px 0; }
.pl-video {
  max-width: 1120px; margin: 0 auto; aspect-ratio: 16 / 9; border-radius: 8px; overflow: hidden; background: var(--ink);
}
.pl-video video, .pl-video iframe { width: 100%; height: 100%; border: 0; background: var(--ink); }
.pl-video-empty {
  height: 100%; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 6px; padding: 24px; text-align: center;
  background: var(--bone); color: var(--text-2);
}
.pl-video-empty .icon { color: var(--text-3); margin-bottom: 6px; }
.pl-video-empty-title { font-size: 15px; font-weight: 600; color: var(--text); }
.pl-video-empty-sub { font-size: 13px; }

.pl-read { max-width: 784px; margin: 0 auto; padding: 32px 32px 72px; }
.pl-lesson-head { padding-bottom: 20px; border-bottom: 1px solid var(--line); margin-bottom: 28px; }
.pl-eyebrow { font-size: 12px; font-weight: 600; letter-spacing: .04em; text-transform: uppercase; color: var(--text-3); margin-bottom: 8px; }
body.is-app .pl-title { font-size: 28px; line-height: 1.2; font-weight: 700; letter-spacing: -0.03em; color: var(--text); text-wrap: balance; }
.pl-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 16px; margin-top: 14px; font-size: 13px; color: var(--text-2); }
.pl-meta-item { display: inline-flex; align-items: center; gap: 6px; }
.pl-meta-item .icon { color: var(--text-3); }
.pl-complete { margin-left: auto; }
.pl-complete.is-done { --bg: var(--ok-tint); --fg: var(--ok-text); --bd: var(--ok-tint); }
.pl-complete.is-done:hover { --bg: var(--ok-tint); }
.pl-done-chip { margin-left: auto; display: inline-flex; align-items: center; gap: 6px; height: 30px; padding: 0 10px; border-radius: 6px; background: var(--ok-tint); color: var(--ok-text); font-weight: 600; font-size: 13px; }

/* article body: comfortable reading */
.pl-prose { font-size: 17px; line-height: 1.7; max-width: 720px; }
.pl .pl-prose h1, .pl .pl-prose h2 { font-size: 22px; line-height: 1.3; font-weight: 700; letter-spacing: -0.02em; margin-top: 1.8em; }
.pl .pl-prose h3 { font-size: 18px; line-height: 1.35; margin-top: 1.5em; }
.pl .pl-prose h4 { font-size: 16px; }
.pl-prose pre { font-size: 14px; }
.pl-summary { max-width: 720px; }
.pl-summary-label { font-size: 12px; font-weight: 600; letter-spacing: .04em; text-transform: uppercase; color: var(--text-3); }
.pl-summary-text { margin: 8px 0 12px; font-size: 17px; line-height: 1.7; color: var(--text); }

/* pager */
.pl-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--line); }
.pl-pager-link { display: flex; flex-direction: column; gap: 4px; min-width: 0; padding: 14px 16px; border: 1px solid var(--line); border-radius: 8px; color: var(--text); transition: border-color .15s var(--ease), background-color .15s var(--ease); }
a.pl-pager-link:hover { border-color: var(--cobalt); color: var(--text); }
.pl-pager-link.is-empty { border-color: transparent; }
.pl-next, .pl-pager-end { text-align: right; align-items: flex-end; }
.pl-pager-end { background: var(--bone); border-color: var(--bone); }
.pl-pager-k { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; font-weight: 600; color: var(--text-3); text-transform: uppercase; letter-spacing: .04em; }
a.pl-pager-link:hover .pl-pager-k { color: var(--cobalt); }
.pl-pager-t { max-width: 100%; font-size: 14px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.pl-kbd-hint { margin-top: 16px; font-size: 12px; color: var(--text-3); text-align: center; }

/* completion panel */
.pl-done-panel { display: grid; grid-template-columns: 44px 1fr; gap: 16px; align-items: start; padding: 20px; margin-bottom: 28px; border: 1px solid var(--ok); border-radius: 8px; background: var(--ok-tint); }
.pl-done-icon { width: 44px; height: 44px; border-radius: 8px; display: grid; place-items: center; background: var(--ok); color: #fff; }
.pl-done-panel h2 { font-size: 17px; font-weight: 600; letter-spacing: -0.015em; color: var(--text); }
.pl-done-panel p { margin-top: 4px; font-size: 14px; color: var(--text-2); }
.pl-done-panel .btn-row { margin-top: 14px; display: flex; flex-wrap: wrap; gap: 8px; }

/* ------------------------------------------------------------ quiz */
.pl-quiz-prev { margin-bottom: 16px; }
.pl-quiz-intro { font-size: 14px; color: var(--text-2); margin-bottom: 8px; }
.pl-q { margin: 0; padding: 24px 0; border: 0; border-top: 1px solid var(--line); min-width: 0; }
.pl-q:first-child { border-top: 0; padding-top: 12px; }
.pl-q-title { float: left; width: 100%; display: flex; gap: 12px; align-items: flex-start; padding: 0; margin-bottom: 14px; font-size: 16px; font-weight: 600; line-height: 1.45; letter-spacing: -0.01em; color: var(--text); }
.pl-q-n { flex: none; width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center; background: var(--bone); font-size: 12px; font-weight: 600; color: var(--text-2); margin-top: -1px; }
.pl-q-opts { clear: both; display: grid; gap: 8px; padding-left: 38px; }
.pl-opt { position: relative; display: grid; grid-template-columns: 18px 1fr; gap: 12px; align-items: center; min-height: 44px; padding: 10px 14px; border: 1px solid var(--line); border-radius: 8px; cursor: pointer; font-size: 15px; transition: border-color .15s var(--ease), background-color .15s var(--ease); }
.pl-opt:hover { border-color: var(--line-strong); background: var(--bone); }
.pl-opt input { position: absolute; opacity: 0; width: 1px; height: 1px; pointer-events: none; }
.pl-opt-dot { width: 18px; height: 18px; border-radius: 50%; border: 1.5px solid var(--line-strong); background: var(--paper); transition: border-color .15s var(--ease); }
.pl-opt input:checked + .pl-opt-dot { border: 5px solid var(--cobalt); }
.pl-opt input:focus-visible + .pl-opt-dot { outline: var(--focus); outline-offset: 2px; }
.pl-opt.is-checked { border-color: var(--cobalt); background: var(--cobalt-tint); }
.pl-opt input:disabled ~ .pl-opt-text { color: var(--text-2); }
.pl-opt:has(input:disabled) { cursor: default; }
.pl-opt:has(input:disabled):hover { background: var(--paper); border-color: var(--line); }
.pl-opt.is-right { border-color: var(--ok); background: var(--ok-tint); }
.pl-opt.is-right .pl-opt-dot, .pl-opt.is-right input:checked + .pl-opt-dot { border: 5px solid var(--ok); }
.pl-opt.is-wrong { border-color: var(--danger); background: var(--danger-tint); }
.pl-opt.is-wrong .pl-opt-dot, .pl-opt.is-wrong input:checked + .pl-opt-dot { border: 5px solid var(--danger); }
.pl-opt.is-right input:disabled ~ .pl-opt-text, .pl-opt.is-wrong input:disabled ~ .pl-opt-text { color: var(--text); }
.pl-q.is-missing .pl-q-n { background: var(--danger); color: #fff; }
.pl-q-why { display: flex; gap: 8px; margin: 12px 0 0 38px; font-size: 14px; color: var(--text-2); line-height: 1.55; }
.pl-q-why .icon { flex: none; margin-top: 2px; }
.pl-q-why.is-right .icon { color: var(--ok); }
.pl-q-why.is-wrong .icon { color: var(--danger); }
.pl-quiz-foot { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 16px; padding-top: 20px; border-top: 1px solid var(--line); }
.pl-quiz-status { font-size: 14px; color: var(--text-2); }
.pl-quiz-result { scroll-margin-top: 24px; display: flex; align-items: center; gap: 16px; padding: 16px 20px; margin-bottom: 8px; border-radius: 8px; background: var(--bone); }
.pl-quiz-result.is-pass { background: var(--ok-tint); }
.pl-quiz-score { font-size: 28px; font-weight: 700; letter-spacing: -0.03em; font-variant-numeric: tabular-nums; }
.pl-quiz-result.is-pass .pl-quiz-score { color: var(--ok-text); }
.pl-quiz-result p { font-size: 14px; color: var(--text-2); }
.pl-quiz-result strong { display: block; color: var(--text); font-size: 15px; font-weight: 600; }

/* ------------------------------------------------------------ curriculum rail */
.pl-rail-head, .pl-tutor-head { flex: none; display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; padding: 16px 16px 12px; border-bottom: 1px solid var(--line); }
body.is-app .pl-panel-title { font-size: 14px; font-weight: 600; letter-spacing: -0.01em; line-height: 1.4; }
.pl-rail-body { flex: 1; min-height: 0; overflow-y: auto; overscroll-behavior: contain; }
.pl-rail-empty { padding: 16px; }
.pl-sec { border-bottom: 1px solid var(--line); }
.pl-sec-head { display: flex; align-items: center; gap: 12px; padding: 12px 16px; cursor: pointer; list-style: none; user-select: none; }
.pl-sec-head::-webkit-details-marker { display: none; }
.pl-sec-head:hover { background: var(--bone); }
.pl-sec-head:focus-visible { outline: var(--focus); outline-offset: -2px; }
.pl-sec-text { flex: 1; min-width: 0; display: flex; flex-direction: column; gap: 2px; }
.pl-sec-title { font-size: 13px; font-weight: 600; line-height: 1.4; color: var(--text); }
.pl-sec-meta { font-size: 12px; color: var(--text-3); font-variant-numeric: tabular-nums; }
.pl-sec-chev { color: var(--text-3); transition: transform .18s var(--ease); }
.pl-sec[open] .pl-sec-chev { transform: rotate(180deg); }
.pl-rows { list-style: none; margin: 0; padding: 0 0 8px; }
.pl-row {
  position: relative; display: grid; grid-template-columns: 20px 1fr; gap: 10px; align-items: start;
  padding: 9px 16px; min-height: 44px; color: var(--text); font-size: 13px; line-height: 1.4;
}
.pl-row:hover { background: var(--bone); color: var(--text); }
.pl-row:focus-visible { outline: var(--focus); outline-offset: -2px; }
.pl-row.is-current { background: var(--cobalt-tint); }
.pl-row.is-current::before { content: ""; position: absolute; left: 0; top: 6px; bottom: 6px; width: 2px; border-radius: 2px; background: var(--cobalt); }
.pl-row.is-current .pl-row-title { color: var(--cobalt-deep); font-weight: 600; }
.pl-row.is-locked { color: var(--text-3); }
.pl-row.is-locked .pl-row-title { color: var(--text-2); }
.pl-row-state { display: grid; place-items: center; height: 19px; color: var(--text-3); }
.pl-check { width: 16px; height: 16px; border-radius: 50%; border: 1.5px solid var(--line-strong); display: grid; place-items: center; color: transparent; transition: background-color .2s var(--ease), border-color .2s var(--ease); }
.pl-check .icon { stroke-width: 2.5; }
.pl-row.is-done .pl-check { background: var(--ok); border-color: var(--ok); color: #fff; }
.pl-row.is-current:not(.is-done) .pl-check { border-color: var(--cobalt); }
.pl-row-main { min-width: 0; display: flex; flex-direction: column; gap: 2px; }
.pl-row-title { overflow-wrap: anywhere; }
.pl-row-meta { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; color: var(--text-3); }
.pl-row-preview { color: var(--cobalt); font-weight: 600; }
.pl-rail-foot { flex: none; padding: 12px 16px; border-top: 1px solid var(--line); }
.pl-rail-foot:empty { display: none; }
.pl-review-line { display: flex; align-items: center; justify-content: space-between; gap: 12px; font-size: 13px; color: var(--text-2); }
.pl-review-line .stars-mini { display: inline-flex; gap: 1px; color: var(--star); }
.pl-review-line .stars-mini .icon { fill: currentColor; }

/* ------------------------------------------------------------ course tutor */
.pl-tutor-id { display: flex; align-items: center; gap: 10px; min-width: 0; }
.pl-tutor-mark { width: 32px; height: 32px; flex: none; border-radius: 8px; display: grid; place-items: center; background: var(--cobalt); color: #fff; }
.pl-tutor-body { flex: 1; min-height: 0; overflow-y: auto; overscroll-behavior: contain; padding: 16px; display: flex; flex-direction: column; gap: 14px; }
.pl-tutor-loading { display: flex; flex-direction: column; gap: 4px; }
.pl-tutor-intro { padding: 4px 0 2px; }
.pl-tutor-intro h3 { font-size: 15px; font-weight: 600; letter-spacing: -0.01em; }
.pl-tutor-intro p { margin-top: 4px; font-size: 13px; color: var(--text-2); }
.pl-suggest { display: flex; flex-direction: column; gap: 6px; margin-top: 12px; }
.pl-suggest button {
  display: flex; align-items: center; gap: 10px; width: 100%; min-height: 38px; padding: 8px 12px; text-align: left;
  border: 1px solid var(--line); border-radius: 8px; font-size: 13px; color: var(--text); background: var(--paper);
  transition: border-color .15s var(--ease), background-color .15s var(--ease);
}
.pl-suggest button:hover { border-color: var(--cobalt); background: var(--cobalt-tint); }
.pl-suggest button:focus-visible { outline: var(--focus); outline-offset: 2px; }
.pl-suggest .icon { color: var(--text-3); }
.pl-msg { max-width: 100%; font-size: 14px; line-height: 1.6; overflow-wrap: anywhere; }
.pl-msg-user { align-self: flex-end; max-width: 86%; padding: 8px 12px; border-radius: 10px 10px 2px 10px; background: var(--cobalt-tint); color: var(--text); white-space: pre-wrap; }
.pl-msg-bot { align-self: stretch; }
.pl-msg-bot .prose { font-size: 14px; line-height: 1.6; max-width: none; }
.pl-msg-bot .prose > * + * { margin-top: .7em; }
.pl-msg-bot .prose pre { font-size: 12.5px; padding: 10px 12px; }
.pl .pl-msg-bot .prose h2, .pl .pl-msg-bot .prose h3 { font-size: 14px; margin-top: 1em; }
.pl-msg-who { display: flex; align-items: center; gap: 6px; margin-bottom: 4px; font-size: 12px; font-weight: 600; color: var(--text-3); }
.pl-msg-lesson { font-weight: 500; }
.pl-msg-error { align-self: stretch; }
.pl-typing { display: inline-flex; gap: 4px; padding: 6px 0; }
.pl-typing span { width: 6px; height: 6px; border-radius: 50%; background: var(--text-3); animation: pl-blink 1.2s infinite ease-in-out; }
.pl-typing span:nth-child(2) { animation-delay: .15s; } .pl-typing span:nth-child(3) { animation-delay: .3s; }
@keyframes pl-blink { 0%, 80%, 100% { opacity: .25; } 40% { opacity: 1; } }
.pl-tutor-gate { margin: auto 0; text-align: center; padding: 24px 8px; }
.pl-tutor-gate .pl-tutor-mark { margin: 0 auto 12px; width: 44px; height: 44px; }
.pl-tutor-gate h3 { font-size: 15px; font-weight: 600; }
.pl-tutor-gate p { margin: 6px auto 16px; max-width: 280px; font-size: 13px; color: var(--text-2); }

.pl-tutor-foot { flex: none; padding: 12px 16px 14px; border-top: 1px solid var(--line); }
.pl-tutor-foot:empty { display: none; }
.pl-ctx { display: inline-flex; align-items: center; gap: 6px; max-width: 100%; height: 26px; padding: 0 10px; margin-bottom: 8px; border-radius: 999px; background: var(--bone); font-size: 12px; color: var(--text-2); }
.pl-ctx span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.pl-ctx strong { font-weight: 600; color: var(--text); }
.pl-composer { position: relative; display: flex; align-items: flex-end; gap: 8px; padding: 6px 6px 6px 12px; border: 1px solid var(--line-strong); border-radius: 10px; background: var(--paper); transition: border-color .15s var(--ease); }
.pl-composer:focus-within { border-color: var(--cobalt); }
.pl-composer textarea { flex: 1; min-width: 0; min-height: 24px; max-height: 160px; margin: 6px 0; padding: 0; border: 0; resize: none; background: transparent; font-size: 14px; line-height: 1.5; }
.pl-composer textarea:focus { outline: none; }
.pl-composer .btn { flex: none; }
.pl-tutor-note { display: flex; justify-content: space-between; gap: 12px; margin-top: 8px; font-size: 12px; color: var(--text-3); }
.pl-demo-line { margin-top: 6px; font-size: 12px; line-height: 1.45; color: var(--text-3); }

/* ------------------------------------------------------------ review dialog */
.pl-stars-input { display: flex; gap: 4px; margin: 4px 0 6px; }
.pl-stars-input button { width: 40px; height: 40px; border-radius: 6px; display: grid; place-items: center; color: var(--line-strong); }
.pl-stars-input button:hover { background: var(--bone); }
.pl-stars-input button:focus-visible { outline: var(--focus); outline-offset: 1px; }
.pl-stars-input button .icon { --i: 28px; }
.pl-stars-input button.is-on { color: var(--star); }
.pl-stars-input button.is-on .icon { fill: currentColor; }
.pl-stars-label { font-size: 13px; color: var(--text-2); min-height: 20px; }
.pl-review-form { display: flex; flex-direction: column; gap: 14px; }

/* ------------------------------------------------------------ phones and small tablets: sheets + tab bar */
@media (max-width: 900px) {
  .pl { height: auto; min-height: calc(100dvh - var(--admin-bar)); padding-bottom: calc(var(--tab-h) + env(safe-area-inset-bottom)); }
  .pl-top { position: sticky; top: var(--admin-bar); padding: 0 8px; gap: 8px; }
  .pl-top-title { gap: 8px; }
  .pl-mode-tag { display: none; }
  .pl-progress-bar { width: 56px; }
  .pl-layout { display: block; }
  .pl-main { overflow: visible; }
  .pl-stage { padding: 0; }
  .pl-video { border-radius: 0; }
  .pl-read { padding: 24px 16px 40px; }
  body.is-app .pl-title { font-size: 24px; }
  .pl-prose, .pl-summary-text { font-size: 16px; }
  .pl-q-opts { padding-left: 0; }
  .pl-q-why { margin-left: 0; }
  .pl-pager { display: flex; flex-direction: column-reverse; margin-top: 32px; }
  .pl-pager-link.is-empty { display: none; }

  .pl-sheet {
    position: fixed; left: 0; right: 0; bottom: calc(var(--tab-h) + env(safe-area-inset-bottom)); z-index: 60;
    display: flex !important; height: min(80dvh, 720px); border: 0; border-top: 1px solid var(--line); border-radius: 16px 16px 0 0;
    transform: translateY(calc(100% + var(--tab-h) + 40px)); visibility: hidden; transition: transform .26s var(--ease), visibility 0s linear .26s;
    animation: none !important;
  }
  .pl-sheet.is-open { transform: none; visibility: visible; transition: transform .26s var(--ease), visibility 0s; }
  .pl-sheet-grip { display: block; flex: none; width: 36px; height: 4px; margin: 8px auto 0; border-radius: 2px; background: var(--line-strong); }
  .pl-rail-head, .pl-tutor-head { padding-top: 10px; }
  .pl-sheet-close { display: inline-flex; }
  .pl-scrim { display: block; position: fixed; inset: 0; z-index: 55; background: rgba(13, 13, 17, .46); }
  .pl-scrim[hidden] { display: none; }
  .pl-tabbar {
    display: grid; grid-template-columns: repeat(3, 1fr); position: fixed; left: 0; right: 0; bottom: 0; z-index: 70;
    height: calc(var(--tab-h) + env(safe-area-inset-bottom)); padding-bottom: env(safe-area-inset-bottom);
    background: var(--paper); border-top: 1px solid var(--line);
  }
  .pl-tab { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; font-size: 12px; font-weight: 500; color: var(--text-3); }
  .pl-tab.is-active { color: var(--cobalt); }
  .pl-tab:focus-visible { outline: var(--focus); outline-offset: -4px; }
  .pl-enrollbar { padding: 8px 8px 8px 16px; }
  .pl-row { min-height: 52px; padding-block: 12px; font-size: 14px; }
  .pl-sec-head { min-height: 52px; }
  body.pl-sheet-open { overflow: hidden; }
}
@media (max-width: 420px) {
  .pl-progress-bar { display: none; }
}
@media (prefers-reduced-motion: reduce) {
  .pl-sheet, .pl-sheet.is-open, .pl.tutor-open .pl-tutor, .pl-main { transition: none; animation: none; scroll-behavior: auto; }
}
@media print {
  .pl-top, .pl-rail, .pl-tutor, .pl-tabbar, .pl-enrollbar, .pl-pager { display: none !important; }
  .pl { height: auto; }
}