/* Topic learning (tt-shell): fresh education palette, calm cards, one clear action.
   Default accent = Toan (fresh blue). Each subject keeps its own fresh accent. */
.tt-shell { --tt-accent: #2563eb; --tt-accent-hover: #1d4ed8; --tt-soft: #eff4ff; --tt-border: #c7d7fc; --tt-icon-bg: #e1eafe; --tt-icon: #2563eb; --tt-eyebrow: #1e40af; --tt-focus: #2563eb; --tt-ink: #182335; --tt-ink-soft: #44506a; --tt-muted: #5b6577; --tt-line: #e3e8f0; --tt-track: #e6ebf3; --subject: var(--tt-accent); --subject-soft: var(--tt-soft); max-width: 1080px; margin: 0 auto; padding: 24px 28px 72px; color: var(--tt-ink); font-family: 'Be Vietnam Pro', sans-serif; }
.tt-shell[data-subject="english"] { --tt-accent: #db2777; --tt-accent-hover: #be185d; --tt-soft: #fff0f6; --tt-border: #f5b8d0; --tt-icon-bg: #ffe0ec; --tt-icon: #db2777; --tt-eyebrow: #be185d; --tt-focus: #db2777; }
.tt-shell[data-subject="tieng-viet"] { --tt-accent: #059669; --tt-accent-hover: #047857; --tt-soft: #ebfbf3; --tt-border: #a9e8c9; --tt-icon-bg: #d9f6e7; --tt-icon: #059669; --tt-eyebrow: #047857; --tt-focus: #059669; }
.tt-shell[data-subject="science"] { --tt-accent: #0d9488; --tt-accent-hover: #0f766e; --tt-soft: #e9fbf8; --tt-border: #a5e6de; --tt-icon-bg: #d6f7f2; --tt-icon: #0d9488; --tt-eyebrow: #0f766e; --tt-focus: #0d9488; }
.tt-shell[data-subject="lich-su-dia-ly"] { --tt-accent: #c2410c; --tt-accent-hover: #9a3412; --tt-soft: #fff4e9; --tt-border: #f3c69b; --tt-icon-bg: #ffe7ce; --tt-icon: #c2410c; --tt-eyebrow: #9a3412; --tt-focus: #c2410c; }
.tt-shell *, .tt-shell *::before, .tt-shell *::after { box-sizing: border-box; }
.tt-shell h1 { font-size: clamp(26px, 3.5vw, 36px); line-height: 1.3; margin: 0 0 10px; overflow-wrap: anywhere; letter-spacing: -.02em; }
.tt-shell h2 { font-size: 22px; line-height: 1.4; margin: 0 0 10px; letter-spacing: -.01em; }
.tt-shell p { line-height: 1.65; margin: 8px 0 16px; }
.tt-shell a { color: inherit; text-decoration: none; }
.tt-back { display: inline-flex; align-items: center; gap: 6px; min-height: 48px; margin-bottom: 8px; padding: 4px 8px 4px 0; font-weight: 700; font-size: 15px; color: var(--tt-ink-soft); background: transparent; border: 0; border-radius: 10px; cursor: pointer; }
.tt-back:hover { color: var(--tt-accent); }
.tt-heading { display: flex; align-items: center; gap: 18px; margin: 16px 0 24px; }
.tt-heading p { color: var(--tt-ink-soft); margin: 0; }
.tt-subject-icon { width: 62px; height: 62px; padding: 15px; border-radius: 22px; background: var(--tt-icon-bg); color: var(--tt-icon); flex: 0 0 auto; }
.tt-subject-icon svg { width: 32px; height: 32px; }
.tt-next { display: flex; justify-content: space-between; align-items: center; gap: 24px; background: var(--tt-soft); border: 1px solid var(--tt-border); border-radius: 20px; padding: 24px 26px; margin-bottom: 32px; }
.tt-next h2 { max-width: 640px; }
.tt-next p:last-child { margin-bottom: 0; color: var(--tt-ink-soft); }
.tt-shell .tt-eyebrow { color: var(--tt-eyebrow); font-size: 14px; font-weight: 800; margin: 0 0 8px; }
.tt-shell .button { min-height: 48px; white-space: normal; text-align: center; border-radius: 14px; font-size: 16px; font-weight: 800; padding: 12px 22px; }
.tt-next .button { flex-shrink: 0; max-width: 250px; }
.tt-shell .button.primary { background: var(--tt-accent); border: 1px solid var(--tt-accent); color: #fff; box-shadow: 0 8px 18px -8px var(--tt-accent); }
.tt-shell .button.primary:hover { background: var(--tt-accent-hover); border-color: var(--tt-accent-hover); }
.tt-shell .button.primary:active { transform: translateY(1px); box-shadow: none; }
.tt-shell .button.secondary { background: #fff; border: 1.5px solid var(--tt-border); color: var(--tt-eyebrow); box-shadow: none; }
.tt-shell .button.secondary:hover { border-color: var(--tt-accent); background: var(--tt-soft); color: var(--tt-accent-hover); }
.tt-list-heading h2 { margin: 0 0 6px; }
.tt-list-heading p { margin: 0 0 20px; }
.tt-list-heading p, .tt-note { color: var(--tt-muted); font-size: 14px; }
.tt-topic-columns, .tt-topic { display: grid; grid-template-columns: 36px minmax(0, 1fr) 240px; column-gap: 16px; align-items: center; padding-inline: 4px; }
.tt-topic-columns { padding-block: 8px 12px; color: #26364a; font-size: 16px; font-weight: 600; }
.tt-topic-column-title { grid-column: 2; }
.tt-sort-btn { grid-column: 3; justify-self: end; display: inline-flex; flex-direction: column; align-items: flex-start; justify-content: center; gap: 2px; min-height: 48px; max-width: 100%; padding: 6px 8px; margin-right: -8px; border: 0; border-radius: 8px; background: transparent; color: inherit; cursor: pointer; font: inherit; font-size: 14px; line-height: 1.5; text-align: left; }
.tt-sort-title { white-space: nowrap; display: inline-flex; align-items: center; gap: 8px; font-weight: 600; }
.tt-sort-icon { display: inline-flex; flex: 0 0 16px; width: 16px; height: 16px; transform: rotate(-90deg); }
.tt-sort-icon svg { width: 100%; height: 100%; }
.tt-sort-btn[data-tt-sort=""] .tt-sort-icon { opacity: .45; }
.tt-sort-btn[data-tt-sort="desc"] .tt-sort-icon { transform: rotate(90deg); }
.tt-sort-direction { color: var(--tt-muted); font-size: 13px; font-weight: 400; }
.tt-sort-btn:hover { background: var(--tt-soft); color: var(--tt-accent); }
.tt-sort-btn[data-tt-sort="asc"], .tt-sort-btn[data-tt-sort="desc"] { color: var(--tt-eyebrow); }
.tt-sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.tt-topics { border-top: 1px solid var(--tt-line); }
.tt-topic { padding-block: 18px; border-bottom: 1px solid var(--tt-line); border-radius: 14px; }
.tt-topic:hover { background: var(--tt-soft); }
.tt-topic--skeleton { pointer-events: none; }
.tt-topic--skeleton:hover { background: transparent; }
.tt-number { display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; background: var(--tt-soft); color: var(--tt-eyebrow); flex-shrink: 0; font-weight: 800; }
.tt-topic-copy { display: flex; flex-direction: column; gap: 8px; flex: 1; min-width: 0; }
.tt-topic-copy strong { font-size: 17px; line-height: 1.5; overflow-wrap: anywhere; }
.tt-topic-star { color: #d99a17; font-size: 15px; margin-left: 2px; }
.tt-topic-copy > span { font-size: 13px; color: var(--tt-muted); line-height: 1.65; }
.tt-shell progress { appearance: none; height: 8px; border: 0; border-radius: 999px; overflow: hidden; background: var(--tt-track); }
.tt-shell progress::-webkit-progress-bar { background: var(--tt-track); }
.tt-shell progress::-webkit-progress-value { background: var(--tt-accent); border-radius: 999px; }
.tt-shell progress::-moz-progress-bar { background: var(--tt-accent); border-radius: 999px; }
.tt-topic progress { width: 140px; max-width: 100%; }
.tt-topic-end { display: flex; align-items: flex-end; flex-direction: column; gap: 6px; min-width: 0; text-align: right; }
.tt-topic-end small { font-size: 12px; }
.tt-status { display: inline-block; font-size: 12px; font-weight: 700; border-radius: 999px; background: #edf1f6; color: #475464; padding: 5px 11px; max-width: 100%; white-space: normal; line-height: 1.5; }
.tt-status--review { background: #fff3df; color: #9a5b0b; }
.tt-status--good { background: #e3f5e9; color: #1e7a44; }
.tt-status--learning { background: #e7f0fd; color: #2456c4; }
.tt-status--excellent { background: #fdf3d3; color: #8a5a00; }
.tt-separate { border-top: 1px solid var(--tt-line); margin-top: 28px; padding-top: 8px; }
.tt-detail-summary { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; background: transparent; border-radius: 16px; padding: 0; }
.tt-detail-summary > div { display: flex; flex-direction: column; gap: 6px; background: var(--tt-soft); border: 1px solid var(--tt-border); border-radius: 16px; padding: 18px; }
.tt-detail-summary strong { font-size: 26px; letter-spacing: -.01em; }
.tt-detail-summary span { font-size: 14px; line-height: 1.6; color: var(--tt-ink-soft); }
.tt-levels, .tt-review { margin-top: 32px; }
.tt-lecture { --subject: var(--tt-accent); min-width: 0; }
.tt-lecture .guide-video { grid-template-columns: minmax(0, 450px); gap: 20px; align-items: center; }
.tt-video-actions { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
.tt-level { display: grid; grid-template-columns: 140px 160px 1fr; gap: 12px; border-bottom: 1px solid var(--tt-line); padding: 16px 0; font-size: 14px; line-height: 1.6; }
.tt-level:last-child { border-bottom: 0; }
.tt-review-link { display: flex; width: 100%; gap: 16px; align-items: center; min-height: 58px; justify-content: space-between; padding: 12px 10px; border: 0; border-bottom: 1px solid var(--tt-line); border-radius: 12px; background: transparent; color: inherit; text-align: left; cursor: pointer; font: inherit; line-height: 1.6; }
.tt-review-link:hover { background: var(--tt-soft); }
.tt-actions { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 24px; }
.tt-round-heading { margin: 8px auto 24px; max-width: 960px; width: 100%; }
.tt-round-heading h1 { font-size: 22px; }
.tt-round-heading progress { width: 100%; }
.tt-question-skill { margin: 0 0 12px; color: var(--tt-ink-soft); font-size: 15px; font-weight: 600; line-height: 1.5; }
.tt-question { max-width: 960px; margin: 0 auto; width: 100%; }
.tt-question .question-card { margin: 0; gap: 14px; }
.tt-question .question-study-main { gap: 10px; }
.tt-shell :focus-visible { outline: 3px solid var(--tt-focus); outline-offset: 3px; }
.tt-shell .practice-lang-toggle { margin: 8px 0 16px; }
.tt-question img, .tt-question svg, .tt-question table, .tt-question .listening-player, .tt-question .question-reading-passage { max-width: 100%; }
.tt-question table, .tt-question .question-reading-passage, .tt-question .question-visual { overflow-x: auto; }
.tt-question .tt-level strong, .tt-level strong { overflow-wrap: anywhere; }
.tt-mastery { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 20px 4px; }
.tt-mastery > span:first-child { display: flex; flex-direction: column; gap: 8px; min-width: 0; }
.tt-mastery small { font-size: 14px; color: var(--tt-muted); line-height: 1.5; }

/* Topic overview: calm hero with one dominant action. */
.tt-overview-heading { margin: 12px 0 20px; }
.tt-overview-heading .tt-overview-status { display: flex; align-items: center; gap: 8px; font-size: 15px; font-weight: 600; color: var(--tt-ink-soft); }
.tt-overview-heading .tt-overview-status::before { content: ""; width: 9px; height: 9px; border-radius: 50%; background: var(--tt-accent); flex: 0 0 auto; }
.tt-learning-layout { display: grid; gap: 20px; padding: 24px 26px; margin-bottom: 20px; background: var(--tt-soft); border: 1px solid var(--tt-border); border-radius: 20px; }
.tt-learning-layout--no-video { padding: 22px 26px; }
.tt-learning-layout--no-video .tt-practice-invite::before { content: "Mỗi lượt tối đa 5 câu. Con đọc kỹ rồi trả lời nhé."; color: var(--tt-ink-soft); font-size: 15px; line-height: 1.6; margin-bottom: 10px; }
.tt-practice-invite { min-width: 0; display: flex; flex-direction: column; align-items: flex-start; gap: 4px; }
.tt-practice-invite p { max-width: 420px; color: var(--tt-ink-soft); margin: 4px 0 12px; }
.tt-practice-invite .button.primary { min-height: 54px; font-size: 17px; padding: 14px 30px; }
.tt-video-actions { margin-top: 12px; justify-content: space-between; max-width: 450px; }
.tt-video-actions .tt-note { margin: 0; }

/* Deep-skill recommendation: its own soft card so it reads as guidance, not clutter. */
section.tt-practice-invite[aria-label="Học sâu kỹ năng còn yếu"] { background: #fff; border: 1px solid var(--tt-line); border-radius: 18px; padding: 20px 22px; margin-bottom: 8px; box-shadow: 0 1px 2px rgba(24, 35, 51, .05); }
section.tt-practice-invite[aria-label="Học sâu kỹ năng còn yếu"] h2 { font-size: 20px; margin-bottom: 4px; }
section.tt-practice-invite[aria-label="Học sâu kỹ năng còn yếu"] p { margin: 4px 0 14px; }

.tt-results { padding-top: 26px; margin-top: 18px; border-top: 1px solid var(--tt-line); }
.tt-results > h2 { margin-bottom: 4px; }
.tt-results .tt-detail-summary { grid-template-columns: repeat(2, minmax(0, 1fr)); margin-top: 16px; }
.tt-results h3 { font-size: 18px; margin: 26px 0 4px; }
.tt-result-details { border: 1px solid var(--tt-line); border-radius: 14px; padding: 0 18px; margin-top: 12px; background: #fff; }
.tt-result-details summary { cursor: pointer; padding: 16px 0; min-height: 48px; font-weight: 700; line-height: 1.6; list-style: none; display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.tt-result-details summary::-webkit-details-marker { display: none; }
.tt-result-details summary::after { content: ""; flex: 0 0 auto; width: 10px; height: 10px; border-right: 2.5px solid var(--tt-eyebrow); border-bottom: 2.5px solid var(--tt-eyebrow); border-bottom-right-radius: 2px; transform: rotate(45deg); transition: transform .2s ease; }
.tt-result-details[open] summary::after { transform: rotate(225deg); }
.tt-result-details summary:hover { color: var(--tt-accent); }
.tt-result-details .tt-note { margin-top: 0; }

.tt-mastery-summary { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 20px; margin: 16px 0; }
.tt-mastery-summary strong { font-size: 22px; color: var(--tt-accent-hover); letter-spacing: -.01em; }
.tt-mastery-summary span { font-size: 14px; color: var(--tt-muted); }
.tt-skill { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 16px 0; border-top: 1px solid var(--tt-line); }
.tt-skill > div { display: grid; gap: 6px; min-width: 0; }
.tt-skill strong { font-size: 15px; line-height: 1.5; }
.tt-skill span { font-size: 14px; color: var(--tt-muted); }
.tt-skill .button { flex-shrink: 0; font-size: 14px; }
.tt-mastery-hero { display: flex; align-items: center; gap: 26px; margin: 16px 0 8px; background: #fff; border: 1px solid var(--tt-line); border-radius: 20px; padding: 24px 26px; box-shadow: 0 1px 2px rgba(24, 35, 51, .05), 0 8px 24px -16px rgba(24, 35, 51, .18); }
.tt-ring { position: relative; width: 124px; height: 124px; flex: 0 0 auto; }
.tt-ring svg { display: block; }
.tt-ring-track { fill: none; stroke: var(--tt-track); stroke-width: 12; }
.tt-ring-fill { fill: none; stroke: var(--tt-accent); stroke-width: 12; stroke-linecap: round; }
.tt-ring.is-empty .tt-ring-fill { stroke: transparent; }
.tt-ring-fill[stroke-dasharray^="0."] { stroke: transparent; }
.tt-ring strong { position: absolute; inset: 0; display: grid; place-items: center; font-size: 26px; letter-spacing: -.01em; }
.tt-ring.is-empty strong { color: var(--tt-muted); }
.tt-mastery-info { min-width: 0; }
.tt-mastery-hero .tt-mastery-summary { margin: 0 0 8px; }
.tt-encourage { font-size: 16px; font-weight: 700; line-height: 1.55; margin: 0 0 8px; }
.tt-mastery-info .tt-note { margin: 0 0 4px; }
.tt-skill-list { margin: 8px 0 4px; }
.tt-skill-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 4px 8px; }
.tt-skill-bar { display: block; height: 8px; border-radius: 999px; background: var(--tt-track); overflow: hidden; margin-top: 4px; }
.tt-skill-bar i { display: block; height: 100%; background: var(--tt-accent); border-radius: 999px; }
.tt-stat-bar { display: block; height: 8px; border-radius: 999px; background: #dbe3ef; overflow: hidden; }
.tt-stat-bar i { display: block; height: 100%; background: var(--tt-accent); border-radius: 999px; }
.tt-review-group h3 { font-size: 15px; line-height: 1.5; margin: 20px 0 4px; color: #26364a; }
.tt-review-group:first-child h3 { margin-top: 8px; }
.tt-review-num { display: grid; place-items: center; width: 32px; height: 32px; border-radius: 50%; background: var(--tt-soft); color: var(--tt-eyebrow); font-weight: 800; font-size: 14px; flex: 0 0 auto; }
.tt-review-stem { flex: 1; min-width: 0; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

/* Skill cards: generous, calm, expandable. */
.tt-skills-head { margin: 24px 0 2px; }
.tt-skills-head h3 { margin: 0 0 4px; font-size: 19px; line-height: 1.45; }
.tt-skills-head .tt-eyebrow { margin: 0 0 4px; }
.tt-skills-head .tt-note { margin: 0; }

.tt-skill-list { display: grid; gap: 12px; margin: 14px 0 8px; border-bottom: 0; }
.tt-skill.tt-skill-card { display: block; background: #fff; border: 1px solid var(--tt-line); border-radius: 18px; padding: 0; overflow: hidden; transition: border-color .15s ease; }
.tt-skill-card:hover { border-color: var(--tt-border); }
.tt-skill-card.is-open { border-color: var(--tt-border); }
.tt-skill-main { min-width: 0; }
.tt-skill-card > .tt-skill-main { display: block; }
.tt-skill-card > .tt-skill-detail { gap: 0; }
.tt-skill-toggle { display: flex; align-items: center; gap: 14px; width: 100%; min-height: 76px; padding: 14px 20px; border: 0; background: transparent; color: inherit; font: inherit; text-align: left; cursor: pointer; border-radius: 18px 18px 0 0; }
.tt-skill-toggle:hover { background: var(--tt-soft); }
.tt-skill-card.is-open .tt-skill-toggle { background: var(--tt-soft); }
.tt-skill-toggle:focus-visible { outline-offset: -3px; }
.tt-skill-static { display: flex; align-items: center; gap: 14px; min-height: 76px; padding: 14px 20px; }
.tt-skill-card .tt-skill-index { display: grid; place-items: center; flex: 0 0 auto; width: 36px; height: 36px; border-radius: 50%; background: var(--tt-soft); color: var(--tt-eyebrow); font-size: 15px; font-weight: 800; }
.tt-skill-card.is-open .tt-skill-index { background: var(--tt-accent); color: #fff; }
.tt-skill-heading { display: grid; gap: 6px; flex: 1; min-width: 0; justify-items: start; text-align: left; }
.tt-skill-card .tt-skill-title { font-size: 16px; line-height: 1.5; overflow-wrap: anywhere; color: var(--tt-ink); }
.tt-skill-card .tt-skill-next-badge { display: inline-flex; align-self: start; align-items: center; min-height: 24px; padding: 3px 12px; border-radius: 999px; background: var(--tt-accent); color: #fff; font-size: 12px; font-weight: 800; letter-spacing: .01em; white-space: nowrap; }
.tt-skill-card .tt-skill-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 5px 10px; font-size: 13px; line-height: 1.5; color: var(--tt-muted); }
.tt-skill-meta-item { display: inline-flex; align-items: center; gap: 6px; }
.tt-skill-card .tt-skill-video-count { display: inline-flex; align-items: center; gap: 5px; color: var(--tt-eyebrow); font-weight: 700; white-space: nowrap; }
.tt-skill-card .tt-skill-video-count::before { content: ""; width: 0; height: 0; border-left: 7px solid currentColor; border-top: 4.5px solid transparent; border-bottom: 4.5px solid transparent; }
.tt-skill-chev { flex: 0 0 auto; width: 11px; height: 11px; margin-right: 2px; border-right: 2.5px solid var(--tt-eyebrow); border-bottom: 2.5px solid var(--tt-eyebrow); border-bottom-right-radius: 2px; transform: rotate(45deg); transition: transform .2s ease; }
.tt-skill-card.is-open .tt-skill-chev { transform: rotate(225deg); }
.tt-skill-card .tt-skill-bar { display: block; height: 8px; margin: 0 20px 16px; border-radius: 999px; background: var(--tt-track); overflow: hidden; }
.tt-skill-card .tt-skill-bar i { display: block; height: 100%; background: var(--tt-accent); border-radius: 999px; }

.tt-skill-detail { display: grid; grid-template-rows: 0fr; transition: grid-template-rows .25s ease; }
.tt-skill-card.is-open .tt-skill-detail { grid-template-rows: 1fr; }
.tt-skill-detail-clip { overflow: hidden; min-height: 0; }
.tt-skill-detail-inner { display: grid; gap: 14px; align-content: start; padding: 16px 20px 18px; border-top: 1px solid var(--tt-line); }
.tt-skill-card .tt-skill-goal { margin: 0; padding: 12px 14px; border: 1px solid var(--tt-border); border-radius: 12px; background: var(--tt-soft); color: #26364a; font-size: 14px; line-height: 1.6; }
.tt-skill-card .tt-skill-goal strong { color: var(--tt-eyebrow); font-size: inherit; }
.tt-skill-card .tt-skill-tip { margin: 0; color: var(--tt-muted); font-size: 13.5px; line-height: 1.6; }
.tt-skill-card .tt-skill-tip strong { color: #26364a; font-size: inherit; }

.tt-skill-card .tt-skill-videos { display: grid; gap: 10px; align-content: start; min-width: 0; }
.tt-skill-videos-heading { display: flex; align-items: center; gap: 8px; margin: 0; color: var(--tt-eyebrow); font-size: 13.5px; font-weight: 800; line-height: 1.5; }
.tt-skill-videos-heading svg { width: 18px; height: 18px; flex: 0 0 auto; }
.tt-skill-card .tt-skill-videos-list { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; align-items: start; }
.tt-skill-card .tt-skill-video { min-width: 0; }
.tt-skill-video .guide-video { height: auto; gap: 10px; margin-top: 0; padding: 0; border: 0; background: transparent; }
.tt-skill-video .guide-video-frame { border-radius: 12px; }
.tt-skill-video .guide-video-play-icon { width: 48px; height: 48px; }
.tt-skill-video .guide-video-play-icon svg { width: 22px; height: 22px; }
.tt-skill-video-duration { position: absolute; right: 8px; bottom: 8px; padding: 3px 9px; border-radius: 999px; background: rgba(16, 24, 40, .85); color: #fff; font-size: 12px; font-weight: 700; line-height: 1.5; pointer-events: none; }
.tt-skill-video .guide-video-caption { margin: 0; font-size: 13px; }
.tt-skill-video .guide-video-caption span { font-size: 12px; }
.tt-skill-video .guide-video-caption strong { display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; color: var(--tt-ink); font-size: 14px; font-weight: 700; line-height: 1.5; }
.tt-skill-video .guide-video-meta { margin: 2px 0 0; color: var(--tt-muted); font-size: 12.5px; line-height: 1.55; }

.tt-skill-card .tt-skill-foot { display: flex; flex-wrap: wrap; gap: 10px; }
.tt-skill-card > .tt-skill-foot { padding: 0 20px 18px; }
.tt-skill-foot .button { flex: 1 1 220px; }

[data-tt-review-cancel][hidden] { display: none; }

/* Guard: a journey entry rendered inside tm/tt shells must stay readable even if legacy markup returns. */
.tm-shell .tm-journey-entry, .tt-shell .tm-journey-entry { display: flex; align-items: center; gap: 16px; min-width: 0; }
.tm-shell .tm-journey-entry .practice-set-accordion-title, .tt-shell .tm-journey-entry .practice-set-accordion-title { flex: 1 1 auto; min-width: 0; }

@media (min-width: 1024px) {
  .tt-lecture .guide-video { grid-template-columns: minmax(0, 450px); }
  .tt-learning-layout { grid-template-columns: minmax(0, 450px) minmax(0, 1fr); gap: 40px; align-items: center; }
  .tt-learning-layout--no-video { grid-template-columns: 1fr; }
  .tt-learning-layout--no-video .tt-practice-invite { flex-direction: row; align-items: center; gap: 20px; }
  .tt-learning-layout--no-video .tt-practice-invite::before { flex: 1; margin-bottom: 0; }
  .tt-learning-layout--no-video .tt-practice-invite .button { flex-shrink: 0; }
}

@media (max-width: 720px) {
  .tt-lecture .guide-video { grid-template-columns: minmax(0, 1fr); gap: 12px; }
  .tt-shell { padding: 16px 16px 56px; }
  .tt-heading { gap: 14px; margin-bottom: 18px; }
  .tt-subject-icon { width: 52px; height: 52px; padding: 11px; border-radius: 18px; }
  .tt-subject-icon svg { width: 30px; height: 30px; }
  .tt-next { flex-direction: column; align-items: stretch; padding: 20px; gap: 18px; border-radius: 18px; }
  .tt-next .button { max-width: none; width: 100%; }
  .tt-topic-columns, .tt-topic { grid-template-columns: 28px minmax(0, 1fr) 112px; column-gap: 8px; }
  .tt-topic-columns { padding-block: 8px; font-size: 16px; grid-template-columns: 28px minmax(0, 1fr) auto; }
  .tt-topic { align-items: start; }
  .tt-number { width: 28px; height: 28px; font-size: 13px; }
  .tt-sort-btn { padding-inline: 4px; margin-right: -4px; }
  .tt-sort-title { gap: 4px; }
  .tt-topic-copy strong { font-size: 15px; }
  .tt-learning-layout { padding: 20px 18px; border-radius: 18px; }
  .tt-practice-invite .button.primary { width: 100%; }
  section.tt-practice-invite[aria-label="Học sâu kỹ năng còn yếu"] { padding: 18px; }
  section.tt-practice-invite[aria-label="Học sâu kỹ năng còn yếu"] .button { width: 100%; }
  .tt-mastery-hero { flex-direction: column; text-align: center; gap: 16px; padding: 22px 18px; }
  .tt-mastery-summary { justify-content: center; }
  .tt-mastery-summary strong { font-size: 20px; }
  .tt-detail-summary { grid-template-columns: 1fr; gap: 10px; }
  .tt-detail-summary > div { padding: 16px; }
  .tt-detail-summary strong { font-size: 24px; }
  .tt-results .tt-detail-summary { grid-template-columns: 1fr; }
  .tt-level { grid-template-columns: 1fr 1fr; }
  .tt-level > span:last-child { grid-column: 1 / -1; }
  .tt-review-link { font-size: 15px; gap: 12px; }
  .tt-skill-toggle, .tt-skill-static { padding: 12px 14px; min-height: 70px; }
  .tt-skill-card .tt-skill-bar { margin: 0 14px 14px; }
  .tt-skill-detail-inner { padding: 14px 14px 16px; }
  .tt-skill-card > .tt-skill-foot { padding: 0 14px 16px; }
  .tt-skill-foot .button { flex: 1 1 100%; }
  .tt-skill-card .tt-skill-videos-list { grid-template-columns: none; grid-auto-flow: column; grid-auto-columns: min(72vw, 280px); overflow-x: auto; overscroll-behavior-x: contain; scroll-snap-type: x mandatory; scroll-padding-inline: 14px; margin: 0 -14px; padding: 4px 14px 8px; }
  .tt-skill-card .tt-skill-video { scroll-snap-align: start; }
  .tt-round-heading { margin-bottom: 16px; }
  .tt-question .question-card-actions { position: sticky; bottom: 0; z-index: 30; margin: 6px -16px -8px; padding: 10px 16px calc(10px + env(safe-area-inset-bottom, 0px)); background: color-mix(in srgb, var(--bg, #f7f8fc), #ffffff 55%); border-top: 1px solid var(--tt-line); }
  .tt-question .question-card:not(.question-card--focus) .question-card-actions .button-row { flex-wrap: nowrap; gap: 10px; }
  .tt-question .question-card:not(.question-card--focus) .question-card-actions .button.primary { flex: 1 1 auto; min-width: 0; }
}

@media (max-width: 600px) {
  .tt-skill { align-items: flex-start; flex-direction: column; gap: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  .tt-skill-detail, .tt-skill-chev, .tt-result-details summary::after, .tt-skill.tt-skill-card { transition: none; }
  .tt-shell .button.primary:active { transform: none; }
}