/* ---- Course layout: sidebar + content (W3Schools-style) ---- */
.pl-course-wrap{display:flex;gap:0;max-width:1300px;margin:0 auto;align-items:flex-start}
.pl-course-sidebar{flex:0 0 280px;position:sticky;top:0;align-self:flex-start;max-height:100vh;overflow-y:auto;
  background:#f6f7f9;border-right:1px solid #e6e8eb;padding:18px 0}
.pl-lesson-main{flex:1 1 auto;min-width:0;padding:28px 40px}

/* ---- Sidebar TOC ---- */
.pl-course-toc__home{display:block;font-weight:700;font-size:15px;padding:8px 22px 12px;color:#111;text-decoration:none;border-bottom:1px solid #e6e8eb;margin-bottom:6px}
.pl-course-toc__section{font-size:12px;text-transform:uppercase;letter-spacing:.04em;color:#8a9099;margin:16px 0 4px;padding:0 22px}
.pl-course-toc__list{list-style:none;margin:0;padding:0}
.pl-course-toc__item a{display:block;padding:7px 22px;color:#3a4149;text-decoration:none;font-size:14.5px;border-left:3px solid transparent}
.pl-course-toc__item a:hover{background:#eceef1;color:#111}
.pl-course-toc__item.is-active a{background:#fff;border-left-color:#4caf50;color:#111;font-weight:600}

/* ---- Breadcrumb ---- */
.pl-breadcrumb{font-size:13px;color:#8a9099;margin-bottom:14px}
.pl-breadcrumb a{color:#4caf50;text-decoration:none}
.pl-breadcrumb span{margin:0 6px;color:#c2c7cc}

/* ---- Lesson body ---- */
.pl-lesson__title{font-size:34px;line-height:1.2;margin:0 0 18px}
.pl-lesson__content{font-size:16.5px;line-height:1.7;color:#2b3138}
.pl-lesson__content h2{font-size:24px;margin:30px 0 12px}
.pl-lesson__content h3{font-size:19px;margin:22px 0 10px}
.pl-lesson__content table{border-collapse:collapse;width:100%;margin:16px 0}
.pl-lesson__content th,.pl-lesson__content td{border:1px solid #e0e3e7;padding:8px 12px;text-align:left}
.pl-lesson__content th{background:#f6f7f9}

/* ---- Code blocks + copy button (Prism okaidia theme is dark) ---- */
.pl-lesson__content pre[class*="language-"]{border-radius:8px;position:relative;font-size:14.5px}
.pl-has-copy{position:relative}
.pl-copy-btn{position:absolute;top:8px;right:8px;background:rgba(255,255,255,.12);color:#fff;border:1px solid rgba(255,255,255,.25);
  border-radius:6px;padding:3px 12px;font-size:12.5px;cursor:pointer;line-height:1.6}
.pl-copy-btn:hover{background:rgba(255,255,255,.22)}

/* ---- Start button + outline ---- */
.pl-start-btn{display:inline-block;background:#4caf50;color:#fff;padding:12px 26px;border-radius:6px;text-decoration:none;font-weight:600;font-size:16px}
.pl-start-btn:hover{background:#43a047}
.pl-course-outline{line-height:1.9}

/* ---- Prev/next ---- */
.pl-lesson-nav{display:flex;justify-content:space-between;gap:16px;margin:36px 0 10px;border-top:1px solid #e6e8eb;padding-top:20px}
.pl-lesson-nav a{display:flex;flex-direction:column;gap:2px;max-width:48%;text-decoration:none;background:#4caf50;color:#fff;padding:12px 18px;border-radius:6px}
.pl-lesson-nav a:hover{background:#43a047}
.pl-lesson-nav__next{text-align:right;margin-left:auto}
.pl-lesson-nav span{font-size:12.5px;opacity:.85}
.pl-lesson-nav strong{font-size:15px}

/* ---- Courses hub ---- */
.pl-hub-wrap{max-width:1100px;margin:0 auto;padding:30px 20px}
.pl-hub-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:18px;margin-top:20px}
.pl-hub-card{display:flex;flex-direction:column;gap:6px;padding:26px 20px;border:1px solid #e6e8eb;border-radius:10px;text-decoration:none;background:#fff;transition:.15s}
.pl-hub-card:hover{border-color:#4caf50;box-shadow:0 4px 14px rgba(0,0,0,.06)}
.pl-hub-card__lang{font-size:22px;font-weight:700;color:#111}
.pl-hub-card__meta{font-size:13px;color:#8a9099}

/* ---- Mobile ---- */
.pl-toc-toggle{display:none;position:sticky;top:0;z-index:20;width:100%;background:#4caf50;color:#fff;border:0;padding:12px;font-size:15px;cursor:pointer;text-align:left}
@media (max-width:900px){
  .pl-course-wrap{flex-direction:column}
  .pl-toc-toggle{display:block}
  .pl-course-sidebar{position:static;flex-basis:auto;width:100%;max-height:0;overflow:hidden;padding:0;border-right:0;border-bottom:1px solid #e6e8eb;transition:max-height .25s}
  .pl-course-sidebar.is-open{max-height:70vh;overflow-y:auto;padding:12px 0}
  .pl-lesson-main{padding:20px}
  .pl-lesson__title{font-size:27px}
}