/* Learning Core v1.3 — danh mục khóa học, chi tiết, học bài, quản trị khóa học. Chỉ giao diện sáng. */
.btn-ok { --b-bg: var(--la); --b-ink: #fff; --b-line: var(--la); }
.chip-sm { min-height: 26px; font-size: 12.5px; padding: 0 10px; }
.lc-state { display: grid; gap: 10px; justify-items: center; text-align: center; padding: 36px 20px; }
.lc-section { margin-bottom: 26px; }
.lc-section > h2 { font-size: 19px; margin: 0 0 12px; letter-spacing: -.02em; }

/* Danh mục */
.lc-filters { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 12px; }
.lc-filters .input { width: auto; min-width: 160px; }
.lc-search { position: relative; flex: 1 1 280px; display: flex; align-items: center; }
.lc-search svg { position: absolute; left: 12px; width: 18px; height: 18px; color: var(--ink-3); pointer-events: none; }
.lc-search .input { width: 100%; padding-left: 38px; }
.lc-domains { margin-bottom: 8px; }
.lc-subjects:empty { display: none; }
.lc-subjects { margin-bottom: 8px; }
.lc-count { display: inline-block; min-width: 20px; padding: 0 6px; margin-left: 2px; border-radius: 999px; background: var(--paper-3); font-size: 11.5px; color: var(--ink-3); }
.chip.on .lc-count { background: rgba(255,255,255,.25); color: inherit; }
.lc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 270px), 1fr)); gap: 16px; }
.lc-card { display: flex; flex-direction: column; gap: 8px; min-width: 0; padding: 18px; background: var(--paper-2); border: 1px solid var(--line); border-radius: 16px; box-shadow: 0 6px 20px -18px rgba(25, 32, 60, .45); transition: box-shadow .16s ease, transform .16s ease; }
.lc-card:hover { box-shadow: 0 14px 28px -22px rgba(25, 32, 60, .5); transform: translateY(-2px); }
.lc-card h3 { margin: 0; font-size: 17px; line-height: 1.35; letter-spacing: -.015em; overflow-wrap: anywhere; }
.lc-card h3 a { color: var(--ink); text-decoration: none; }
.lc-card h3 a:hover { color: var(--tim); }
.lc-card p { margin: 0; color: var(--ink-2); font-size: 14px; line-height: 1.55; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.lc-card-top { display: flex; justify-content: space-between; align-items: center; gap: 8px; }
.lc-dom { font-size: 12.5px; font-weight: 700; color: var(--tim); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.lc-meta { display: flex; flex-wrap: wrap; gap: 6px 12px; font-size: 13px; color: var(--ink-3); }
.lc-meta > span { display: inline-flex; align-items: center; gap: 5px; }
.lc-meta svg { width: 15px; height: 15px; }
.lc-meta-lg { font-size: 14px; margin-top: 12px; }
.lc-card-act { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-top: auto; padding-top: 6px; }
.lc-card-act .small svg { width: 14px; height: 14px; vertical-align: -2px; margin-right: 3px; }
.lc-card-mine { border-color: color-mix(in srgb, var(--tim) 30%, var(--line)); }
.lc-module { text-decoration: none; color: inherit; background: linear-gradient(180deg, var(--tim-soft), var(--paper-2) 70%); }
.lc-more { margin-top: auto; font-weight: 700; color: var(--tim); display: inline-flex; align-items: center; gap: 4px; font-size: 14px; }
.lc-more svg { width: 16px; height: 16px; }
.lc-prog { display: grid; gap: 4px; }
.lc-bar { height: 8px; border-radius: 999px; background: var(--paper-3); overflow: hidden; }
.lc-bar i { display: block; height: 100%; background: var(--la); border-radius: 999px; transition: width .3s ease; }
.lc-resume { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 16px; flex-wrap: wrap; }
.lc-resume > div { display: grid; gap: 4px; min-width: 0; flex: 1 1 260px; }
.lc-resume b { font-size: 17px; }

/* Chi tiết khóa học */
.lc-detail { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 20px; align-items: start; }
.lc-hero { padding: 26px; border-radius: 20px; background: linear-gradient(135deg, var(--tim-soft), var(--paper-2)); border: 1px solid var(--line); }
.lc-hero h1 { margin: 8px 0 6px; font-size: clamp(24px, 3vw, 32px); letter-spacing: -.03em; line-height: 1.2; overflow-wrap: anywhere; }
.lc-hero .lead { margin: 0; color: var(--ink-2); line-height: 1.6; }
.lc-path { font-size: 13px; font-weight: 600; color: var(--ink-3); }
.lc-side { position: sticky; top: 84px; display: grid; gap: 10px; }
.lc-side h3 { margin: 0; font-size: 16px; }
.lc-side p { margin: 0; }
.lc-locked { display: flex; gap: 8px; align-items: flex-start; color: var(--ink-2); font-size: 14px; }
.lc-locked svg { width: 18px; height: 18px; flex: none; margin-top: 1px; color: var(--cam); }
.lc-done { display: inline-flex; align-items: center; gap: 6px; color: var(--la); font-weight: 700; margin: 0; }
.lc-done svg { width: 18px; height: 18px; }
.lc-units { list-style: none; margin: 8px 0 0; padding: 0; display: grid; gap: 6px; }
.lc-unit { display: flex; align-items: center; gap: 12px; padding: 11px 12px; border: 1px solid var(--line); border-radius: 12px; color: var(--ink); text-decoration: none; background: var(--paper-2); }
a.lc-unit:hover { border-color: var(--tim); background: var(--tim-soft); }
.lc-unit.locked { color: var(--ink-3); }
.lc-num { width: 26px; height: 26px; border-radius: 8px; background: var(--paper-3); display: grid; place-items: center; font-size: 12.5px; font-weight: 700; flex: none; }
.lc-ut { color: var(--tim); display: grid; place-items: center; flex: none; }
.lc-ut svg { width: 18px; height: 18px; }
.lc-ttl { display: grid; gap: 2px; flex: 1; min-width: 0; }
.lc-ttl b { font-weight: 650; overflow-wrap: anywhere; }
.lc-st { width: 22px; height: 22px; border-radius: 50%; border: 2px solid var(--line-2); display: grid; place-items: center; flex: none; color: var(--ink-3); }
.lc-st svg { width: 14px; height: 14px; }
.lc-st.done { background: var(--la); border-color: var(--la); color: #fff; }
.lc-st.doing { border-color: var(--cam); background: radial-gradient(circle, var(--cam) 0 35%, transparent 40%); }

/* Nội dung Markdown */
.lc-md { line-height: 1.75; font-size: 16px; color: var(--ink); overflow-wrap: anywhere; }
.lc-md h2 { font-size: 22px; margin: 22px 0 10px; letter-spacing: -.02em; }
.lc-md h3 { font-size: 19px; margin: 20px 0 8px; }
.lc-md h4, .lc-md h5 { font-size: 16.5px; margin: 16px 0 6px; }
.lc-md > :first-child { margin-top: 0; }
.lc-md p { margin: 0 0 12px; }
.lc-md ul, .lc-md ol { margin: 0 0 12px; padding-left: 24px; }
.lc-md li { margin: 3px 0; }
.lc-md code { font-family: "JetBrains Mono", ui-monospace, monospace; font-size: .9em; background: var(--paper-3); padding: 1px 6px; border-radius: 6px; }
.lc-md pre.md-code { background: #F3F4F9; border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; overflow-x: auto; margin: 0 0 14px; }
.lc-md pre.md-code code { background: none; padding: 0; font-size: 14px; line-height: 1.6; white-space: pre; }
.lc-md blockquote { margin: 0 0 12px; padding: 8px 16px; border-left: 4px solid var(--tim); background: var(--tim-soft); border-radius: 0 10px 10px 0; }
.lc-md blockquote p:last-child { margin: 0; }
.lc-md hr { border: 0; border-top: 1px solid var(--line); margin: 18px 0; }
.lc-md a { color: var(--tim); }
.md-table { overflow-x: auto; margin: 0 0 14px; }
.md-table table { border-collapse: collapse; min-width: 100%; font-size: 14.5px; }
.md-table th, .md-table td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; }
.md-table th { background: var(--paper-3); }

/* Học bài */
.lc-learn { display: grid; grid-template-columns: 300px minmax(0, 1fr); min-height: calc(100vh - var(--top-h, 64px)); background: var(--paper); }
.lc-aside { border-right: 1px solid var(--line); background: var(--paper-2); padding: 18px 14px; position: sticky; top: var(--top-h, 64px); height: calc(100vh - var(--top-h, 64px)); overflow-y: auto; }
.lc-ohead { display: grid; gap: 8px; padding: 0 6px 14px; border-bottom: 1px solid var(--line); margin-bottom: 10px; }
.lc-ohead a { font-weight: 650; color: var(--ink); text-decoration: none; overflow-wrap: anywhere; }
.lc-outline { list-style: none; margin: 0; padding: 0; display: grid; gap: 2px; }
.lc-outline a { display: flex; gap: 10px; align-items: flex-start; padding: 9px 8px; border-radius: 10px; color: var(--ink); text-decoration: none; }
.lc-outline a:hover { background: var(--paper-3); }
.lc-outline a.on { background: var(--tim-soft); }
.lc-outline a.on b { color: var(--tim); }
.lc-outline span:last-child { display: grid; gap: 1px; min-width: 0; }
.lc-outline b { font-size: 14px; font-weight: 600; overflow-wrap: anywhere; }
.lc-outline small { color: var(--ink-3); font-size: 12px; }
.lc-main { padding: 28px clamp(16px, 4vw, 48px) 40px; max-width: 900px; width: 100%; min-width: 0; }
.lc-uhead { margin-bottom: 18px; }
.lc-uhead h1 { margin: 4px 0 0; font-size: clamp(22px, 3vw, 30px); letter-spacing: -.03em; line-height: 1.25; overflow-wrap: anywhere; }
.lc-mob-outline { display: none; }
.lc-ref { display: grid; gap: 10px; justify-items: start; padding: 22px; border: 1px solid var(--line); border-radius: 16px; background: var(--paper-2); }
.lc-ref h2 { margin: 0; font-size: 20px; }
.lc-ref p { margin: 0; line-height: 1.6; }
.lc-ref .lc-bar { width: 100%; }
.lc-foot { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin-top: 32px; padding-top: 18px; border-top: 1px solid var(--line); flex-wrap: wrap; }
.lc-complete { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; justify-content: center; }

/* Quản trị khóa học */
.ac-layout { display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 16px; align-items: start; }
.ac-tree { display: grid; gap: 2px; position: sticky; top: 84px; max-height: calc(100vh - 110px); overflow-y: auto; }
.ac-tree-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 8px; }
.ac-node { display: flex; justify-content: space-between; gap: 6px; width: 100%; text-align: left; border: 0; background: none; padding: 7px 8px; border-radius: 8px; color: var(--ink); font: inherit; font-size: 14px; cursor: pointer; }
.ac-node:hover { background: var(--paper-3); }
.ac-node.on { background: var(--tim-soft); color: var(--tim); font-weight: 650; }
.ac-node span { color: var(--ink-3); font-size: 12px; }
.ac-node em { font-style: normal; color: var(--ink-3); font-size: 12px; }
.ac-sub { padding-left: 22px; font-size: 13.5px; }
.ac-mod { padding-left: 38px; font-size: 13px; color: var(--ink-2); }
.ac-dom { margin-top: 4px; }
.ac-filters { gap: 10px; flex-wrap: wrap; margin-bottom: 12px; align-items: center; }
.ac-filters .input { flex: 1 1 220px; width: auto; }
.ac-table td { vertical-align: top; }
.ac-acts { display: flex; gap: 6px; flex-wrap: wrap; justify-content: flex-end; }
.ac-crumb { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; flex-wrap: wrap; }
.ac-crumb a:first-child { font-weight: 650; }
.ac-crumb .btn { margin-left: auto; }
.ac-edit { display: grid; gap: 16px; }
.ac-form { display: grid; grid-template-columns: 1fr 1fr; gap: 12px 16px; }
.ac-span2 { grid-column: 1 / -1; }
.ac-save { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; border-top: 1px solid var(--line); padding-top: 12px; }
.ac-units { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.ac-units li { display: grid; grid-template-columns: auto minmax(0, 1fr) auto auto; gap: 10px; align-items: center; padding: 10px 12px; border: 1px solid var(--line); border-radius: 12px; background: var(--paper-2); }
.ac-units li.arch { opacity: .6; }
.ac-ord { display: flex; gap: 2px; }
.ac-ord .icon-btn { width: 30px; height: 30px; font-weight: 700; }
.ac-uinfo { display: grid; gap: 2px; min-width: 0; }
.ac-uinfo b { overflow-wrap: anywhere; }
.ac-pick-list { max-height: 260px; overflow-y: auto; border: 1px solid var(--line); border-radius: 10px; padding: 8px 10px; display: grid; gap: 4px; margin: 6px 0 12px; }
.ac-pick-list .check { display: flex; gap: 8px; align-items: center; font-size: 14px; }
.modal.ac-modal { max-width: 1100px; width: min(1100px, calc(100vw - 24px)); }

/* Ô soạn Markdown */
.md-ed { border: 1px solid var(--line-2); border-radius: 12px; overflow: hidden; background: var(--paper-2); }
.md-tools { display: flex; gap: 2px; flex-wrap: wrap; align-items: center; padding: 6px; border-bottom: 1px solid var(--line); background: var(--paper-3); }
.md-tools button { border: 0; background: none; min-width: 32px; height: 30px; border-radius: 7px; cursor: pointer; font: inherit; font-size: 14px; color: var(--ink); }
.md-tools button:hover { background: var(--paper-2); }
.md-tabs { margin-left: auto; display: flex; gap: 2px; }
.md-tabs button { padding: 0 10px; font-size: 13px; font-weight: 600; }
.md-tabs button.on { background: var(--paper-2); color: var(--tim); }
.md-panes { display: grid; grid-template-columns: 1fr 1fr; min-height: 220px; }
.md-panes textarea { border: 0; border-right: 1px solid var(--line); border-radius: 0; resize: vertical; padding: 12px; font-family: "JetBrains Mono", ui-monospace, monospace; font-size: 13.5px; line-height: 1.6; min-height: 220px; width: 100%; background: var(--paper-2); color: var(--ink); }
.md-panes textarea:focus { outline: 2px solid var(--tim); outline-offset: -2px; }
.md-preview { padding: 12px 16px; max-height: 520px; overflow-y: auto; font-size: 15px; }
.md-tabs button[data-v="edit"], .md-tabs button[data-v="preview"] { display: none; }

@media (max-width: 1100px) {
  .lc-detail { grid-template-columns: 1fr; }
  .lc-side { position: static; order: -1; }
  .ac-layout { grid-template-columns: 1fr; }
  .ac-tree { position: static; max-height: 240px; }
}
@media (max-width: 900px) {
  .lc-learn { grid-template-columns: 1fr; }
  .lc-aside { display: none; }
  .lc-mob-outline { display: block; margin-bottom: 16px; border: 1px solid var(--line); border-radius: 12px; background: var(--paper-2); }
  .lc-mob-outline summary { cursor: pointer; padding: 12px 14px; font-weight: 650; display: flex; align-items: center; gap: 8px; list-style: none; }
  .lc-mob-outline summary svg { width: 18px; height: 18px; }
  .lc-mob-outline[open] summary { border-bottom: 1px solid var(--line); }
  .lc-mob-outline .lc-ohead, .lc-mob-outline .lc-outline { padding: 10px 12px; }
  .lc-mob-outline .lc-ohead { margin: 0; }
  .md-tabs button[data-v="edit"], .md-tabs button[data-v="preview"] { display: inline-block; }
  .md-panes { grid-template-columns: 1fr; }
  .md-panes textarea { border-right: 0; }
  .md-ed:not(.preview) .md-preview { display: none; }
  .md-ed.preview textarea { display: none; }
}
@media (max-width: 640px) {
  .ac-form { grid-template-columns: 1fr; }
  .ac-units li { grid-template-columns: auto minmax(0, 1fr); }
  .ac-units li > div:nth-child(3), .ac-units li > .ac-acts { grid-column: 2; justify-content: flex-start; }
  .lc-foot { justify-content: center; }
  .lc-foot > * { flex: 1 1 100%; justify-content: center; }
  .lc-hero { padding: 18px; }
}
.ac-form { align-items: start; }