:root {
  --ink: #242338;
  --muted: #6f6c7e;
  --paper: #f8f6f1;
  --surface: #ffffff;
  --line: #e5e0d8;
  --violet: #6254a3;
  --violet-dark: #453b7b;
  --violet-soft: #efebfb;
  --coral: #d57961;
  --gold: #d8aa54;
  --green: #398064;
  --green-soft: #e7f3ed;
  --red: #a85048;
  --red-soft: #faece9;
  --font-sans: "DM Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-serif: "Newsreader", Georgia, "Times New Roman", serif;
  --font-glyph: Georgia, "Apple Symbols", "Segoe UI Symbol", "Noto Sans Symbols 2", serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, "Roboto Mono", monospace;
  /* Medida de linha. Em DM Sans 1ch vale ~1,43 caractere real, então
     50ch ≈ 72 caracteres por linha — a faixa confortável de leitura. */
  --measure: 50ch;
  --measure-lead: 46ch;
  --measure-wide: 68ch;
  --radius: 18px;
  --shadow: 0 14px 40px rgba(45, 39, 69, 0.08);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--font-sans); font-optical-sizing: auto; font-variant-ligatures: common-ligatures contextual; line-height: 1.6; }
body.course-active { overflow: hidden; }
[hidden] { display: none !important; }
button, select, input { font: inherit; }
button { color: inherit; }
button:focus-visible, select:focus-visible, input:focus-visible, a:focus-visible { outline: 3px solid rgba(98, 84, 163, .35); outline-offset: 3px; }

.app-boot { min-height: 100vh; min-height: 100dvh; display: grid; place-content: center; justify-items: center; gap: 3px; padding: 24px; background: radial-gradient(circle at 50% 42%, rgba(98,84,163,.1), transparent 24%), var(--paper); text-align: center; }
.app-boot-mark { display: grid; place-items: center; width: 68px; height: 68px; margin-bottom: 15px; border-radius: 50%; background: rgba(255,255,255,.72); box-shadow: 0 14px 40px rgba(45,39,69,.08); }
.app-boot .brand-mark { animation: boot-orbit 1.4s cubic-bezier(.65,0,.35,1) infinite; }
.app-boot > p:last-child { margin: 3px 0 0; color: var(--muted); font-size: .88rem; }

.auth-gate { position: relative; min-height: 100vh; display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(380px, .72fr); gap: clamp(42px, 7vw, 112px); align-items: center; padding: clamp(42px, 7vw, 96px); overflow: hidden; background: radial-gradient(circle at 78% 15%, rgba(216,170,84,.16), transparent 28%), radial-gradient(circle at 8% 82%, rgba(213,121,97,.15), transparent 31%), linear-gradient(145deg, #f5f1e9, #f2edf7 54%, #edf2ed); }
.auth-atmosphere { position: absolute; inset: 0; pointer-events: none; }
.auth-orbit { position: absolute; border: 1px solid rgba(98,84,163,.13); border-radius: 50%; transform: rotate(-18deg); }
.auth-orbit-one { width: min(62vw, 820px); height: min(24vw, 320px); left: -14vw; top: 11vh; }
.auth-orbit-two { width: min(48vw, 650px); height: min(19vw, 250px); right: -18vw; bottom: 8vh; border-color: rgba(213,121,97,.18); transform: rotate(24deg); }
.auth-planet { position: absolute; width: 11px; height: 11px; left: 28%; top: 17%; border-radius: 50%; background: var(--violet); box-shadow: 0 0 0 9px rgba(98,84,163,.08); }
.auth-intro, .auth-card { position: relative; z-index: 1; }
.auth-brand { width: fit-content; margin-bottom: clamp(54px, 10vh, 104px); font-size: 1.25rem; }
.auth-intro h1 { max-width: 680px; margin: 15px 0 22px; font-size: clamp(3rem, 6.3vw, 6.4rem); line-height: .9; }
.auth-intro > p:not(.eyebrow) { max-width: 620px; margin: 0; color: var(--muted); font-size: clamp(1rem, 1.5vw, 1.18rem); }
.auth-benefits { max-width: 650px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 48px 0 0; padding: 0; list-style: none; }
.auth-benefits li { padding: 18px 16px; border-top: 1px solid rgba(98,84,163,.25); color: var(--ink); font-size: .82rem; line-height: 1.45; }
.auth-benefits span { display: block; margin-bottom: 7px; color: var(--violet); font-size: .68rem; font-weight: 700; letter-spacing: .1em; }
.auth-card { width: 100%; max-width: 520px; justify-self: end; padding: clamp(30px, 4vw, 50px); border: 1px solid rgba(255,255,255,.85); border-radius: 28px; background: rgba(255,255,255,.75); box-shadow: 0 28px 80px rgba(45,39,69,.13); backdrop-filter: blur(22px); }
.auth-card-heading h2 { margin: 7px 0 8px; font-size: clamp(2rem, 3.4vw, 3rem); }
.auth-card-heading > p:last-child { margin: 0; color: var(--muted); font-size: .9rem; }
.auth-form { display: grid; margin-top: 30px; }
.auth-form label { margin: 15px 0 7px; font-size: .76rem; font-weight: 700; letter-spacing: .025em; }
.auth-form label > span { margin-left: 5px; color: var(--muted); font-weight: 500; }
.auth-key-group { display: grid; animation: auth-mode-reveal .24s ease both; }
.auth-field { display: grid; grid-template-columns: 30px 1fr; align-items: center; min-height: 52px; padding: 0 14px; border: 1px solid #ddd6e4; border-radius: 12px; background: rgba(248,246,241,.82); transition: border-color .22s ease, box-shadow .22s ease, background .22s ease; }
.auth-field:focus-within { border-color: var(--violet); background: white; box-shadow: 0 0 0 4px rgba(98,84,163,.08); }
.auth-field > span { color: var(--violet); font-size: .76rem; font-weight: 700; }
.auth-field input { width: 100%; min-width: 0; padding: 13px 0; border: 0; outline: 0; color: var(--ink); background: transparent; }
.auth-field input::placeholder { color: #9b97a4; }
.auth-submit { display: flex; justify-content: space-between; align-items: center; min-height: 54px; margin-top: 25px; padding: 0 20px; border: 0; border-radius: 12px; color: white; background: var(--violet); box-shadow: 0 12px 28px rgba(69,59,123,.21); cursor: pointer; font-weight: 700; transition: transform .22s ease, background .22s ease, box-shadow .22s ease; }
.auth-submit:hover:not(:disabled) { transform: translateY(-2px); background: var(--violet-dark); box-shadow: 0 16px 32px rgba(69,59,123,.25); }
.auth-submit:disabled { opacity: .65; cursor: wait; }
.auth-mode-prompt { display: flex; flex-wrap: wrap; justify-content: center; gap: 5px; margin: 14px 0 0; color: var(--muted); font-size: .8rem; }
.auth-mode-prompt button { padding: 0; border: 0; color: var(--violet-dark); background: transparent; cursor: pointer; font-weight: 700; text-decoration: underline; text-decoration-color: rgba(98,84,163,.28); text-underline-offset: 3px; }
.auth-mode-prompt button:hover:not(:disabled) { color: var(--violet); text-decoration-color: currentColor; }
.auth-mode-prompt button:disabled { opacity: .6; cursor: wait; }
.auth-status { min-height: 1.5em; margin: 10px 0 0; color: var(--red); font-size: .8rem; }
.auth-status.success { color: var(--green); }
.auth-privacy { display: flex; gap: 9px; margin: 20px 0 0; padding-top: 18px; border-top: 1px solid var(--line); color: var(--muted); font-size: .72rem; }
.auth-privacy span { color: var(--green); }

.skip-link { position: fixed; z-index: 20; top: 10px; left: 10px; padding: 8px 12px; background: var(--ink); color: white; transform: translateY(-150%); }
.skip-link:focus { transform: none; }
.topbar { height: 72px; padding: 0 30px; display: flex; align-items: center; justify-content: space-between; gap: 24px; border-bottom: 1px solid var(--line); background: rgba(248, 246, 241, .94); position: sticky; top: 0; z-index: 10; backdrop-filter: blur(12px); }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); text-decoration: none; font-weight: 700; letter-spacing: -.02em; font-size: 1.1rem; }
.brand-mark { width: 29px; height: 29px; border: 1.5px solid var(--violet); border-radius: 50%; display: grid; place-items: center; position: relative; }
.brand-mark::after { content: ""; width: 38px; height: 13px; border: 1px solid var(--coral); border-radius: 50%; position: absolute; transform: rotate(-22deg); }
.brand-mark span { width: 6px; height: 6px; border-radius: 50%; background: var(--violet); }
.course-progress { min-width: 185px; display: flex; align-items: center; gap: 12px; color: var(--muted); font-size: .82rem; }
.progress-track { width: 90px; height: 5px; overflow: hidden; border-radius: 8px; background: var(--line); }
.progress-track span { height: 100%; width: 0; display: block; background: var(--violet); transition: width .35s ease; }
.mobile-menu { display: none; border: 1px solid var(--line); background: var(--surface); border-radius: 9px; padding: 7px 10px; }
.account-menu { display: flex; align-items: center; gap: 10px; margin-left: auto; color: var(--muted); font-size: .76rem; }
.account-menu span { max-width: 220px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.account-menu button { padding: 6px 10px; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); cursor: pointer; font-size: .72rem; font-weight: 700; }
.account-menu button:hover { border-color: var(--violet); background: var(--violet-soft); }

.admin-view { height: calc(100vh - 72px); height: calc(100dvh - 72px); overflow-y: auto; overscroll-behavior: contain; background: radial-gradient(circle at 92% 0, rgba(216,170,84,.13), transparent 28%), linear-gradient(155deg, #f8f6f1 0%, #f2eef8 100%); scrollbar-width: thin; scrollbar-color: rgba(69,59,123,.22) transparent; }
.admin-view::-webkit-scrollbar { width: 7px; }
.admin-view::-webkit-scrollbar-track { background: transparent; }
.admin-view::-webkit-scrollbar-thumb { border: 2px solid transparent; border-radius: 999px; background: rgba(69,59,123,.28); background-clip: padding-box; }
.admin-shell { width: min(1440px, 100%); margin: 0 auto; padding: 52px clamp(24px, 5vw, 72px) 80px; }
.admin-heading { display: flex; justify-content: space-between; gap: 36px; align-items: flex-start; margin-bottom: 28px; }
.admin-heading h1 { margin: 5px 0 8px; font-size: clamp(2.7rem, 5vw, 4.8rem); }
.admin-heading p:last-child { max-width: 680px; margin: 0; color: var(--muted); }
.admin-back { flex: 0 0 auto; min-height: 44px; padding: 9px 15px; border: 1px solid var(--line); border-radius: 10px; background: rgba(255,255,255,.82); cursor: pointer; font-weight: 700; }
.admin-back:hover { border-color: var(--violet); background: var(--violet-soft); }
.admin-page-status { min-height: 1.5em; margin: -12px 0 18px; color: var(--green); font-size: .875rem; }
.admin-page-status.is-error { color: var(--red); }
.admin-metrics { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-bottom: 20px; }
.admin-metrics article { position: relative; min-height: 154px; padding: 23px; overflow: hidden; border: 1px solid rgba(255,255,255,.9); border-radius: 18px; background: rgba(255,255,255,.78); box-shadow: var(--shadow); }
.admin-metrics article > span { position: absolute; top: 18px; right: 20px; color: rgba(98,84,163,.28); font-size: 1.5rem; }
.admin-metrics strong { display: block; color: var(--violet-dark); font: 600 clamp(2.4rem, 4vw, 3.6rem)/1 var(--font-serif); }
.admin-metrics p { margin: 10px 0 0; color: var(--muted); font-size: .875rem; font-weight: 600; }
.admin-card { margin-top: 20px; padding: clamp(24px, 3vw, 36px); border: 1px solid rgba(255,255,255,.92); border-radius: 20px; background: rgba(255,255,255,.84); box-shadow: var(--shadow); }
.admin-card h2 { margin-top: 4px; font-size: clamp(1.8rem, 3vw, 2.55rem); }
.admin-key-generator { display: grid; grid-template-columns: minmax(0, 1fr) max-content; gap: 24px 36px; align-items: center; }
.admin-key-generator > div:first-child > p:last-child { max-width: 760px; margin: 7px 0 0; color: var(--muted); }
.admin-primary-action { min-height: 50px; padding: 11px 19px; border: 0; border-radius: 11px; color: white; background: var(--violet); box-shadow: 0 12px 28px rgba(69,59,123,.2); cursor: pointer; font-weight: 700; }
.admin-primary-action:hover:not(:disabled) { background: var(--violet-dark); transform: translateY(-1px); }
.admin-primary-action:disabled { opacity: .62; cursor: wait; }
.admin-key-reveal { grid-column: 1 / -1; display: grid; grid-template-columns: minmax(0, 1fr) max-content; gap: 18px; align-items: center; padding: 18px 20px; border: 1px solid rgba(57,128,100,.24); border-radius: 14px; background: var(--green-soft); }
.admin-key-reveal span { display: block; margin-bottom: 5px; color: #35624f; font-size: .8125rem; }
.admin-key-reveal code { display: block; overflow-wrap: anywhere; color: var(--ink); font: 700 clamp(.9rem, 1.6vw, 1.08rem)/1.5 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: .025em; user-select: all; }
.admin-key-reveal button { min-height: 42px; padding: 8px 14px; border: 1px solid rgba(57,128,100,.32); border-radius: 9px; background: white; cursor: pointer; font-weight: 700; }
.admin-card-heading { display: flex; justify-content: space-between; gap: 28px; align-items: end; margin-bottom: 22px; }
.admin-card-heading p:last-child { max-width: 520px; margin: 0; color: var(--muted); font-size: .8125rem; text-align: right; }
.admin-table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 13px; }
.admin-table { width: 100%; min-width: 980px; border-collapse: collapse; background: rgba(255,255,255,.7); font-size: .875rem; }
.admin-table th, .admin-table td { padding: 14px 16px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: middle; }
.admin-table th { color: var(--muted); background: #f6f3ee; font-size: .8125rem; font-weight: 700; letter-spacing: .02em; }
.admin-table tbody tr:last-child td { border-bottom: 0; }
.admin-table tbody tr:hover { background: rgba(239,235,251,.45); }
.admin-key-hint { color: var(--violet-dark); font-family: var(--font-mono); font-weight: 700; }
.admin-key-actions { display: flex; align-items: center; gap: 8px; }
.admin-key-label { min-width: 130px; max-width: 260px; overflow-wrap: anywhere; }
.admin-label-dialog { width: min(440px, calc(100vw - 32px)); max-height: calc(100dvh - 32px); padding: 26px; border: 1px solid var(--line); border-radius: 16px; color: var(--ink); background: #fffdf9; box-shadow: 0 20px 70px #201b3433; }
.admin-label-dialog::backdrop { background: #201b3466; }
.admin-label-dialog h2 { margin: 0 0 20px; font-size: 1.5rem; }
.admin-label-dialog label { display: block; margin-bottom: 8px; }
.admin-label-dialog input { box-sizing: border-box; width: 100%; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; font: inherit; color: var(--ink); background: white; }
.admin-label-dialog [role="status"] { color: var(--muted); font-size: .875rem; }
.admin-dialog-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 20px; }
.admin-icon-action.admin-table-action { display: inline-grid; place-items: center; width: 34px; min-height: 34px; padding: 7px; flex: none; }
.admin-icon-action svg { width: 18px; height: 18px; }
.admin-label-dialog input:focus-visible, .admin-table-action:focus-visible { outline: 2px solid var(--violet); outline-offset: 2px; }
.admin-table-action { min-height: 36px; padding: 7px 11px; border: 1px solid rgba(69,59,123,.24); border-radius: 8px; color: var(--violet-dark); background: white; cursor: pointer; font-size: .8125rem; font-weight: 700; }
.admin-table-action:hover:not(:disabled) { border-color: var(--violet); background: var(--violet-soft); }
.admin-table-action.is-danger { color: #8a3f36; border-color: rgba(155,75,63,.28); }
.admin-table-action.is-danger:hover:not(:disabled) { border-color: #9b4b3f; background: var(--red-soft); }
.admin-table-action:disabled { opacity: .46; cursor: not-allowed; }
.admin-key-no-actions { color: var(--muted); }
.admin-person-email { font-weight: 600; }
.admin-state { display: inline-flex; align-items: center; min-height: 27px; padding: 3px 9px; border-radius: 999px; font-size: .75rem; font-weight: 700; }
.admin-state.is-available { color: #35624f; background: var(--green-soft); }
.admin-state.is-used { color: #805149; background: var(--red-soft); }
.admin-empty-state { padding: 28px !important; color: var(--muted); text-align: center !important; }

#course-app { height: 100vh; height: 100dvh; overflow: hidden; }
.app-layout { display: grid; grid-template-columns: 285px minmax(0, 1fr); height: calc(100vh - 72px); height: calc(100dvh - 72px); min-height: 0; overflow: hidden; }
.sidebar { min-height: 0; padding: 36px 24px 40px 30px; overflow-y: auto; overscroll-behavior: contain; border-right: 1px solid var(--line); background: #f3f0ea; }
.sidebar-intro h2 { margin: 3px 0 4px; font: 600 1.45rem/1.2 var(--font-serif); }
.sidebar-intro p:last-child, .sidebar-note { margin: 0; color: var(--muted); font-size: .82rem; }
.sidebar-note { border-top: 1px solid var(--line); padding-top: 18px; margin-top: 24px; }
.eyebrow { margin: 0; color: var(--violet); font-size: .72rem; font-weight: 600; letter-spacing: .11em; text-transform: uppercase; }
.nav-module { margin-top: 28px; }
.nav-module > p { display: flex; align-items: center; gap: 9px; margin: 0 0 8px; color: var(--muted); font-size: .77rem; font-weight: 700; text-transform: uppercase; letter-spacing: .07em; }
.nav-module > p span { color: var(--violet); }
.nav-module ol { list-style: none; padding: 0; margin: 0; display: grid; gap: 4px; }
.nav-module button { width: 100%; border: 0; border-radius: 10px; padding: 9px 10px; display: grid; grid-template-columns: 26px 1fr; gap: 8px; align-items: start; text-align: left; background: transparent; cursor: pointer; font-size: .85rem; line-height: 1.3; }
.nav-module button:hover:not(:disabled), .nav-module button.is-current { background: var(--surface); box-shadow: 0 4px 16px rgba(45, 39, 69, .05); }
.nav-module button:disabled { color: #aaa6af; cursor: not-allowed; }
.lesson-status { height: 22px; width: 22px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 50%; color: var(--muted); font-size: .68rem; }
.nav-module .is-current .lesson-status { border-color: var(--violet); color: var(--violet); background: var(--violet-soft); }
.nav-module .is-complete .lesson-status { border-color: var(--green); color: white; background: var(--green); }
.nav-module button small { display: block; margin-top: 2px; color: var(--muted); font-size: .68rem; }

#lesson-content { min-width: 0; min-height: 0; overflow-y: auto; overscroll-behavior: contain; scroll-behavior: smooth; }
.sidebar, #lesson-content { scrollbar-width: thin; scrollbar-color: rgba(69,59,123,.22) transparent; }
.sidebar::-webkit-scrollbar, #lesson-content::-webkit-scrollbar { width: 7px; height: 7px; }
.sidebar::-webkit-scrollbar-track, #lesson-content::-webkit-scrollbar-track { background: transparent; }
.sidebar::-webkit-scrollbar-thumb, #lesson-content::-webkit-scrollbar-thumb { border: 2px solid transparent; border-radius: 999px; background: rgba(69,59,123,.22); background-clip: padding-box; }
.sidebar:hover::-webkit-scrollbar-thumb, #lesson-content:hover::-webkit-scrollbar-thumb { background-color: rgba(69,59,123,.38); }
.loading-state { padding: 80px; color: var(--muted); }
.lesson { max-width: 1120px; margin: 0 auto; padding: 64px clamp(28px, 6vw, 84px) 80px; animation: lesson-enter .55s cubic-bezier(.2,.75,.25,1) both; }
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.lesson-hero { display: grid; grid-template-columns: minmax(0, 1fr) 250px; gap: 60px; align-items: end; margin-bottom: 72px; }
.lesson-hero-compact { margin-bottom: 34px; }
.lesson-hero-compact h1 { font-size: clamp(2.4rem, 4.7vw, 4rem); }
h1, h2, h3, h4 { font-family: var(--font-serif); font-optical-sizing: auto; text-wrap: balance; }
h1, h2 { letter-spacing: -.025em; }
h1 { max-width: 720px; margin: 10px 0 18px; font-size: clamp(2.65rem, 5vw, 4.5rem); line-height: 1; font-weight: 600; }
h2 { margin: 5px 0 8px; font-size: clamp(1.75rem, 3vw, 2.55rem); line-height: 1.08; }
h3, h4 { font-weight: 600; line-height: 1.16; letter-spacing: -.012em; }
h3 { margin: 8px 0 5px; font-size: 1.2rem; }
h4 { margin: 8px 0 5px; font-size: 1.0625rem; }
p, li, dd, figcaption, blockquote { text-wrap: pretty; }
.lesson-lead { max-width: var(--measure-lead); margin: 0; color: var(--muted); font-size: 1.08rem; line-height: 1.62; }
.lesson-goal { display: flex; gap: 13px; align-items: flex-start; padding: 17px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface); box-shadow: var(--shadow); }
.goal-icon { display: grid; place-items: center; flex: 0 0 32px; height: 32px; border-radius: 50%; color: var(--violet); background: var(--violet-soft); font-size: 1.2rem; }
.lesson-goal strong, .lesson-goal span { display: block; }
.lesson-goal div span { margin-top: 2px; color: var(--muted); font-size: .8rem; line-height: 1.45; }
.section-navigation { position: relative; margin: 0 0 46px; padding: 5px 0 18px; overflow-x: auto; scrollbar-width: thin; }
.section-navigation::before { content: ""; position: absolute; left: 24px; right: 24px; top: 25px; height: 1px; background: var(--line); }
.section-navigation ol { position: relative; display: grid; grid-template-columns: repeat(var(--section-count, 5), minmax(120px, 1fr)); gap: 8px; min-width: max(680px, calc(var(--section-count, 5) * 128px)); margin: 0; padding: 0; list-style: none; }
.section-navigation button { width: 100%; display: grid; justify-items: center; gap: 7px; padding: 0 8px 10px; border: 0; border-radius: 12px; background: transparent; cursor: pointer; text-align: center; }
.section-navigation button:hover, .section-navigation button.is-current { background: rgba(255,255,255,.7); }
.section-step-status { position: relative; z-index: 1; display: grid; place-items: center; width: 42px; height: 42px; border: 1px solid var(--line); border-radius: 50%; color: var(--muted); background: var(--paper); font-size: .76rem; font-weight: 700; transition: transform .2s ease, background .2s ease; }
.section-step-number { line-height: 1; }
.section-complete-mark { position: absolute; right: -3px; bottom: -3px; display: grid; place-items: center; width: 17px; height: 17px; border: 2px solid var(--paper); border-radius: 50%; color: white; background: var(--green); font-size: .62rem; line-height: 1; }
.section-navigation button.is-current .section-step-status { transform: scale(1.08); border-color: var(--violet); color: white; background: var(--violet); box-shadow: 0 0 0 5px var(--violet-soft); }
.section-navigation button.is-complete .section-step-status { border-color: var(--green); color: white; background: var(--green); }
.section-navigation strong, .section-navigation small { display: block; }
.section-navigation strong { font-size: .75rem; line-height: 1.25; }
.section-navigation small { margin-top: 2px; color: var(--muted); font-size: .66rem; }
.lesson-materials { margin: -22px 0 40px; }
.lesson-materials h2 { margin: 0 0 12px; font-size: .78rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--violet-dark); font-family: inherit; }
.lesson-materials ul { display: flex; flex-wrap: wrap; gap: 12px; margin: 0; padding: 0; list-style: none; }
.lesson-materials a { display: grid; gap: 2px; padding: 12px 18px 12px 44px; border: 1px solid var(--line); border-radius: 14px; background: var(--surface) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%236254a3' stroke-width='1.9' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M12 3v12m0 0 4-4m-4 4-4-4'/%3E%3Cpath d='M4 17v2a2 2 0 0 0 2 2h12a2 2 0 0 0 2-2v-2'/%3E%3C/svg%3E") 16px center/18px no-repeat; text-decoration: none; color: inherit; }
.lesson-materials a:hover { border-color: var(--violet); background-color: var(--violet-soft); }
.lesson-materials strong { font-size: .92rem; }
.lesson-materials small { color: var(--muted); font-size: .72rem; }
.section-content { min-height: 320px; scroll-margin-top: 92px; }
.lesson-section { animation: section-enter .42s cubic-bezier(.2,.75,.25,1) both; }
.section-intro { max-width: 760px; margin-bottom: 34px; }
.section-intro h2 { margin-top: 7px; font-size: clamp(2.1rem, 4vw, 3.35rem); }
.section-intro > p:not(.eyebrow) { max-width: var(--measure); }
.section-intro > p:last-child { margin: 12px 0 0; color: var(--muted); font-size: 1.02rem; line-height: 1.62; }
.lesson-section .audio-guide { margin: 0 0 22px; }
.lesson-section .dialogue-sample { margin: 0 0 38px; }
.section-content-block { margin-top: 0; }
.section-takeaway { display: grid; grid-template-columns: 125px 1fr; gap: 20px; margin: 34px 0; padding: 20px 22px; border: 1px solid #ded7ef; border-radius: 14px; background: linear-gradient(135deg, #f2eefb, #faf3ee); }
.section-takeaway strong { color: var(--violet-dark); }
.section-takeaway p { margin: 0; color: var(--muted); }
.learning-objectives { display: grid; gap: 8px; max-width: 760px; margin: 24px 0 0; padding: 0; list-style: none; }
.learning-objectives li { position: relative; padding-left: 28px; color: var(--muted); font-size: .9rem; }
.learning-objectives li::before { content: ""; position: absolute; left: 2px; top: .62em; width: 10px; height: 10px; border: 2px solid var(--violet); border-radius: 50%; box-shadow: inset 0 0 0 2px var(--paper); background: var(--violet-soft); }
.narration-card { margin-bottom: 58px !important; }
.concept-section, .knowledge-check { margin: 64px 0; }
.reference-note { display: flex; gap: 22px; margin: 34px 0; padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); font-size: .82rem; }
.reference-note strong { flex: 0 0 145px; color: var(--violet-dark); }
.reference-note p { margin: 0; color: var(--muted); }
.knowledge-check { padding: clamp(26px, 4vw, 42px); border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.knowledge-question + .knowledge-question { margin-top: 32px; padding-top: 30px; border-top: 1px solid var(--line); }
.knowledge-question h2 { max-width: 820px; font-size: clamp(1.45rem, 2.6vw, 2.05rem); }
.knowledge-question h3 { font-size: 1.4rem; }
.knowledge-options { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; margin-top: 20px; }
.knowledge-options button { padding: 13px 16px; border: 1px solid var(--line); border-radius: 10px; background: var(--paper); text-align: left; cursor: pointer; }
.knowledge-options button:hover { border-color: var(--violet); }
.knowledge-options button.is-correct { border-color: var(--green); background: var(--green-soft); }
.knowledge-options button.is-wrong { border-color: var(--red); background: var(--red-soft); }
.knowledge-feedback { margin-top: 14px; padding: 13px 16px; border-radius: 9px; font-size: .88rem; }
.knowledge-feedback.success { color: #245a45; background: var(--green-soft); }
.knowledge-feedback.try-again { color: #813b35; background: var(--red-soft); }
.knowledge-feedback strong { margin-right: 4px; }
.audio-guide { position: relative; display: grid; grid-template-columns: 150px minmax(0, 1fr); gap: clamp(24px, 5vw, 54px); align-items: center; margin: -18px 0 72px; padding: clamp(24px, 4vw, 38px); overflow: hidden; border: 1px solid #ded7ef; border-radius: var(--radius); background: linear-gradient(135deg, #f1edf9, #f8efe9 58%, #eef4ed); box-shadow: var(--shadow); }
.audio-guide::after { content: ""; position: absolute; width: 220px; height: 220px; right: -90px; top: -120px; border: 1px solid rgba(98,84,163,.12); border-radius: 50%; }
.audio-orbit { position: relative; width: 132px; height: 132px; display: grid; place-items: center; }
.audio-orbit span { position: absolute; inset: 0; border: 1px solid rgba(98,84,163,.28); border-radius: 50%; }
.audio-orbit span:nth-child(2) { inset: 14px; border-color: rgba(213,121,97,.35); }
.audio-orbit span:nth-child(3) { inset: 30px; border-color: rgba(216,170,84,.42); }
.audio-orbit strong { position: relative; z-index: 1; display: grid; place-items: center; width: 48px; height: 48px; padding-left: 3px; border-radius: 50%; color: white; background: var(--violet); box-shadow: 0 8px 24px rgba(69,59,123,.24); font-size: .85rem; }
.audio-content { position: relative; z-index: 1; min-width: 0; }
.audio-content h2 { margin: 4px 0 3px; font-size: clamp(1.55rem, 3vw, 2.15rem); }
.audio-content > p:not(.eyebrow) { margin: 0 0 14px; color: var(--muted); }
.course-audio-element { display: none; }
.course-audio-player { width: 100%; margin: 8px 0 10px; }
.course-audio-controls { display: grid; grid-template-columns: 42px minmax(170px, 1fr) minmax(92px, 120px) 72px; gap: 12px; align-items: center; }
.course-audio-controls.has-regeneration { grid-template-columns: 42px minmax(170px, 1fr) minmax(92px, 120px) 72px 34px; }
.course-audio-toggle { width: 42px; height: 42px; display: grid; place-items: center; padding: 0; border: 0; border-radius: 50%; color: white; background: var(--violet); box-shadow: 0 7px 18px rgba(69,59,123,.2); cursor: pointer; transition: transform .22s ease, background .22s ease, box-shadow .22s ease; }
.course-audio-toggle:hover:not(:disabled) { transform: translateY(-1px); background: var(--violet-dark); box-shadow: 0 9px 22px rgba(69,59,123,.24); }
.course-audio-toggle:disabled { opacity: .58; cursor: wait; }
.course-audio-toggle-icon { position: relative; display: block; width: 14px; height: 14px; }
.course-audio-toggle-icon.is-play::before { content: ""; position: absolute; left: 4px; top: 1px; border-top: 6px solid transparent; border-bottom: 6px solid transparent; border-left: 9px solid white; }
.course-audio-toggle-icon.is-pause::before,
.course-audio-toggle-icon.is-pause::after { content: ""; position: absolute; top: 1px; width: 4px; height: 12px; border-radius: 1px; background: white; }
.course-audio-toggle-icon.is-pause::before { left: 2px; }
.course-audio-toggle-icon.is-pause::after { right: 2px; }
.course-audio-timeline { min-width: 0; display: grid; grid-template-columns: minmax(90px, 1fr) max-content; gap: 10px; align-items: center; }
.course-audio-player input[type="range"] { min-width: 0; margin: 0; accent-color: var(--violet); cursor: pointer; }
.course-audio-player input[type="range"]:disabled { cursor: wait; opacity: .55; }
.course-audio-time { min-width: 76px; color: var(--muted); font-variant-numeric: tabular-nums; font-size: .8125rem; text-align: right; white-space: nowrap; }
.course-audio-volume { min-width: 0; display: flex; gap: 7px; align-items: center; color: var(--muted); }
.course-audio-volume-toggle { flex: 0 0 28px; width: 28px; height: 28px; display: grid; place-items: center; padding: 0; border: 0; border-radius: 50%; color: var(--muted); background: transparent; cursor: pointer; transition: color .2s ease, background .2s ease; }
.course-audio-volume-toggle:hover { color: var(--violet-dark); background: rgba(98,84,163,.08); }
.course-audio-volume-toggle[data-muted="true"] { color: var(--red); background: rgba(168,80,72,.08); }
.course-audio-volume-icon { flex: 0 0 18px; width: 18px; height: 18px; }
.course-audio-volume-icon svg { display: block; width: 100%; height: 100%; }
.course-audio-volume-muted-mark { display: none; }
.course-audio-volume-toggle[data-muted="true"] .course-audio-volume-wave { display: none; }
.course-audio-volume-toggle[data-muted="true"] .course-audio-volume-muted-mark { display: inline; }
.course-audio-volume input { width: 100%; }
.course-audio-rate { width: 72px; min-height: 38px; padding: 5px 7px; border: 1px solid rgba(98,84,163,.2); border-radius: 9px; color: var(--violet-dark); background: rgba(255,255,255,.72); cursor: pointer; font-size: .875rem; font-weight: 700; }
.course-audio-regenerate { width: 34px; height: 34px; display: grid; place-items: center; padding: 0; border: 1px solid rgba(98,84,163,.24); border-radius: 50%; color: var(--violet-dark); background: rgba(255,255,255,.78); cursor: pointer; transition: color .2s ease, border-color .2s ease, background .2s ease, transform .2s ease; }
.course-audio-regenerate svg { width: 18px; height: 18px; }
.course-audio-regenerate:hover:not(:disabled) { color: white; border-color: var(--violet); background: var(--violet); transform: rotate(-18deg); }
.course-audio-regenerate:disabled { opacity: .62; cursor: wait; }
.course-audio-regenerate.is-running svg { animation: audio-regeneration-spin 1.15s linear infinite; }
.course-audio-status:not(.visually-hidden) { margin: 8px 0 0 54px; padding: 8px 10px; border-radius: 8px; color: #813b35; background: var(--red-soft); font-size: .875rem; }
.course-audio-status.is-progress:not(.visually-hidden) { color: var(--violet-dark); background: var(--violet-soft); }
.course-audio-status.is-success:not(.visually-hidden) { color: #35624f; background: var(--green-soft); }
.audio-transcript { border-top: 1px solid rgba(98,84,163,.16); }
.audio-transcript summary { padding: 11px 0 5px; color: var(--violet-dark); cursor: pointer; font-size: .8rem; font-weight: 700; }
.audio-transcript p { margin: 8px 0 0; color: var(--muted); font-size: .86rem; line-height: 1.85; }
.transcript-word { border-radius: 4px; transition: color .12s ease, background .12s ease; }
.transcript-word.is-speaking { color: var(--violet-dark); background: #ded5f4; }
.context-audio-stack { display: grid; grid-column: 1 / -1; gap: 12px; min-width: 0; width: 100%; margin: 28px 0 22px; }
.context-audio-pair { overflow: hidden; border: 1px solid #e2d6e7; border-radius: 18px; color: var(--ink); background: linear-gradient(135deg, #fbf2ef, #f5f0fa); box-shadow: 0 10px 28px rgba(45,39,69,.07); }
.context-audio-pair-label { display: flex; align-items: center; gap: 10px; margin: 0; padding: 11px 20px; border-bottom: 1px solid rgba(98,84,163,.13); color: var(--violet-dark); background: rgba(255,255,255,.42); font-size: .8rem; }
.context-audio-pair-label span { display: inline-grid; place-items: center; min-width: 44px; height: 26px; border-radius: 999px; color: white; background: linear-gradient(90deg, var(--coral) 0 49%, var(--violet) 51% 100%); font-size: .68rem; font-weight: 800; letter-spacing: .04em; }
.context-audio-pair-label strong { font-size: inherit; letter-spacing: .06em; text-transform: uppercase; }
.context-audio-pair-body { display: grid; grid-template-columns: 118px minmax(0, 1fr); gap: 22px; align-items: center; padding: 20px; }
.context-audio-pair-voices { display: flex; align-items: center; justify-content: center; }
.context-audio-pair-voices .voice-avatar { width: 48px; height: 48px; border-width: 3px; font-size: 1.1rem; }
.context-audio-pair-voices .voice-line { width: 18px; }
.context-audio-pair-content { min-width: 0; }
.context-audio-pair .context-audio-pair-content .eyebrow { color: var(--violet); }
.context-audio-pair-content h3 { margin: 3px 0 4px; color: var(--ink); font-size: clamp(1.18rem, 2vw, 1.48rem); }
.context-audio-pair-description { margin: 0 0 10px; color: var(--muted); font-size: .86rem; }
.context-audio-card { display: grid; grid-template-columns: 62px minmax(0, 1fr); gap: 18px; align-items: start; padding: 18px 20px; border: 1px solid #ded7ef; border-radius: 16px; color: var(--ink); background: linear-gradient(135deg, #f4f0fa, #faf5f0); box-shadow: 0 10px 28px rgba(45,39,69,.07); }
.context-audio-card[data-speaker="estudante"] { border-color: #eadbd7; background: linear-gradient(135deg, #fbf2ef, #f6f1fa); }
.context-audio-identity { padding-top: 3px; }
.context-audio-identity .voice-avatar { width: 48px; height: 48px; border-width: 3px; font-size: 1.1rem; }
.context-audio-content { min-width: 0; }
.context-audio-card .context-audio-content .eyebrow { color: var(--violet); }
.context-audio-content h3 { margin: 3px 0 9px; color: var(--ink); font-size: clamp(1.18rem, 2vw, 1.48rem); }
.context-audio-group-sequence { display: grid; margin: 16px 0 0; padding: 0; border-top: 1px solid rgba(98,84,163,.16); list-style: none; }
.context-audio-group-item { min-width: 0; padding: 18px 0 10px; }
.context-audio-group-item + .context-audio-group-item { border-top: 1px solid rgba(98,84,163,.16); }
.context-audio-group-item-header { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: 12px; align-items: baseline; }
.context-audio-group-item-header span { color: var(--violet-dark); font-size: .8125rem; font-weight: 800; letter-spacing: .04em; text-transform: uppercase; }
.context-audio-group-item-header h4 { margin: 0; color: var(--ink); font-size: clamp(1.05rem, 1.6vw, 1.22rem); line-height: 1.35; }
.context-audio-group-item .course-audio-player { margin-top: 12px; }
.context-audio-transcript { margin-top: 8px; border-top: 1px solid rgba(98,84,163,.16); }
.context-audio-card[data-speaker="estudante"] .context-audio-transcript { border-top-color: rgba(213,121,97,.22); }
.context-audio-transcript summary { padding: 9px 0 2px; color: var(--violet-dark); cursor: pointer; font-size: .875rem; font-weight: 700; }
.context-audio-transcript p { display: grid; grid-template-columns: minmax(64px, max-content) 1fr; gap: 12px; margin: 8px 0 0; color: var(--muted); font-size: .86rem; line-height: 1.75; }
.context-audio-transcript strong { color: var(--ink); }
.context-audio-card[data-speaker="estudante"] .transcript-word.is-speaking { color: #7b372d; background: #f3d7cf; }
.context-audio-dialogue-transcript > div { display: grid; gap: 7px; margin-top: 8px; }
.context-audio-dialogue-transcript p { margin: 0; padding: 5px 7px; border-radius: 8px; transition: background .18s ease; }
.context-audio-dialogue-transcript p.is-speaking { background: rgba(98,84,163,.06); }
.context-audio-dialogue-transcript p[data-speaker="estudante"].is-speaking { background: rgba(213,121,97,.08); }
.context-audio-dialogue-transcript p[data-speaker="estudante"] .transcript-word.is-speaking { color: #7b372d; background: #f3d7cf; }
.context-audio-loading,
.context-audio-error { padding: 16px 20px; border: 1px solid var(--line); border-radius: 14px; color: var(--muted); background: var(--surface); font-size: .86rem; }
.context-audio-error { color: #813b35; background: var(--red-soft); }
.dialogue-sample { display: grid; grid-template-columns: 150px minmax(0, 1fr); gap: clamp(24px, 5vw, 54px); align-items: center; margin: -50px 0 72px; padding: clamp(22px, 4vw, 34px); border: 1px solid #eadbd7; border-radius: var(--radius); background: linear-gradient(135deg, #fbf2ef, #f5f0fa); }
.dialogue-voices { display: flex; align-items: center; justify-content: center; }
.voice-avatar { position: relative; z-index: 1; display: grid; place-items: center; width: 54px; height: 54px; border: 4px solid var(--surface); border-radius: 50%; color: white; box-shadow: 0 8px 20px rgba(45,39,69,.12); font-family: var(--font-serif); font-size: 1.3rem; }
.voice-avatar.narrator { background: var(--violet); }
.voice-avatar.student { background: var(--coral); }
.voice-avatar.is-speaking { transform: translateY(-3px) scale(1.08); box-shadow: 0 0 0 6px rgba(98,84,163,.1), 0 10px 24px rgba(45,39,69,.18); }
.voice-avatar.student.is-speaking { box-shadow: 0 0 0 6px rgba(213,121,97,.12), 0 10px 24px rgba(45,39,69,.18); }
.voice-line { width: 24px; height: 1px; background: #cfbfd5; }
.dialogue-content { min-width: 0; }
.dialogue-content h2 { margin: 4px 0 3px; font-size: clamp(1.4rem, 2.8vw, 1.9rem); }
.dialogue-content > p:not(.eyebrow) { margin: 0 0 12px; color: var(--muted); }
.dialogue-script { margin-top: 10px; border-top: 1px solid rgba(213,121,97,.2); }
.dialogue-script summary { padding: 10px 0 3px; color: var(--violet-dark); cursor: pointer; font-size: .8rem; font-weight: 700; }
.dialogue-script div { display: grid; gap: 8px; margin-top: 8px; }
.dialogue-script p { display: grid; grid-template-columns: 64px 1fr; gap: 12px; margin: 0; color: var(--muted); font-size: .82rem; }
.dialogue-script strong { color: var(--ink); }
.dialogue-script p { padding: 5px 7px; border-radius: 8px; transition: background .18s ease; }
.dialogue-script p.is-speaking { background: rgba(98,84,163,.06); }
.dialogue-script p[data-speaker="estudante"].is-speaking { background: rgba(213,121,97,.08); }
.dialogue-script p[data-speaker="estudante"] .transcript-word.is-speaking { color: #7b372d; background: #f3d7cf; }
.content-section { margin: 72px 0; }
.section-heading { max-width: var(--measure-wide); margin-bottom: 30px; }
.section-heading.compact { margin-bottom: 24px; }
.section-heading > p:last-child { max-width: var(--measure); margin: 0; color: var(--muted); }

.critical-note { display: grid; grid-template-columns: 170px 1fr; gap: 20px; margin-top: 22px; padding: 19px 22px; border-left: 3px solid var(--gold); background: #f1ece1; }
.critical-note p { margin: 0; color: var(--muted); font-size: .86rem; }


.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 19px 42px 19px 0; list-style: none; cursor: pointer; font-weight: 700; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; right: 8px; top: 15px; display: grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; color: var(--violet); background: var(--violet-soft); font-size: 1.15rem; font-weight: 500; transition: transform .22s ease, background .22s ease; }
.faq-list details[open] summary::after { transform: rotate(45deg); background: #e4dcf7; }
.faq-list details > div { max-width: 790px; padding: 0 42px 20px 0; color: var(--muted); animation: faq-reveal .28s ease both; }
.faq-list details p { margin: 0; }

.lesson-footer { display: flex; justify-content: space-between; gap: 28px; align-items: center; padding-top: 36px; border-top: 1px solid var(--line); }
.lesson-footer p:last-child { max-width: 630px; margin: 5px 0 0; color: var(--muted); }
.section-save-status { margin: 18px 0; padding: 11px 14px; border-radius: 9px; color: #813b35; background: var(--red-soft); font-size: .82rem; }


@keyframes lesson-enter {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes auth-mode-reveal {
  from { opacity: 0; transform: translateY(-5px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes boot-orbit {
  0%, 100% { transform: rotate(0deg); }
  50% { transform: rotate(180deg); }
}

@keyframes section-enter {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}


@keyframes faq-reveal {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes content-change {
  from { opacity: .38; transform: translateY(7px) scale(.995); filter: blur(1.5px); }
  to { opacity: 1; transform: translateY(0) scale(1); filter: blur(0); }
}

@keyframes audio-regeneration-spin {
  to { transform: rotate(360deg); }
}

@media (max-width: 980px) {
  .auth-gate { grid-template-columns: 1fr; gap: 52px; padding: 42px clamp(24px, 8vw, 72px) 72px; }
  .auth-brand { margin-bottom: 64px; }
  .auth-intro h1 { max-width: 760px; }
  .auth-card { max-width: 680px; justify-self: start; }
  .app-layout { grid-template-columns: 1fr; }
  .mobile-menu { display: block; }
  .course-progress { margin-left: auto; }
  .sidebar { position: fixed; z-index: 9; top: 72px; bottom: 0; left: 0; width: min(320px, 88vw); transform: translateX(-105%); transition: transform .25s ease; box-shadow: var(--shadow); }
  .sidebar.is-open { transform: none; }
  .lesson { padding-top: 48px; }
  .admin-metrics { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 760px) {
  .auth-gate { padding: 28px 20px 52px; }
  .auth-brand { margin-bottom: 52px; }
  .auth-intro h1 { font-size: clamp(2.8rem, 15vw, 4.7rem); }
  .auth-benefits { grid-template-columns: 1fr; gap: 0; margin-top: 34px; }
  .auth-benefits li { display: grid; grid-template-columns: 34px 1fr; align-items: center; gap: 8px; padding: 12px 0; }
  .auth-benefits span { margin: 0; }
  .auth-card { padding: 28px 22px; border-radius: 20px; }
  .topbar { padding: 0 18px; }
  .course-progress { display: none; }
  .account-menu span { display: none; }
  .admin-shell { padding: 36px 20px 60px; }
  .admin-heading, .admin-card-heading { align-items: flex-start; flex-direction: column; gap: 16px; }
  .admin-card-heading p:last-child { text-align: left; }
  .admin-key-generator { grid-template-columns: 1fr; }
  .admin-primary-action { width: 100%; }
  .admin-key-reveal { grid-column: auto; grid-template-columns: 1fr; }
  .admin-key-reveal button { width: 100%; }
  .lesson { padding-inline: 20px; }
  .lesson-hero { grid-template-columns: 1fr; gap: 28px; margin-bottom: 52px; }
  .lesson-goal { max-width: 350px; }
  .section-navigation { margin-bottom: 34px; }
  .audio-guide { grid-template-columns: 1fr; margin-top: -8px; }
  .audio-orbit { width: 88px; height: 88px; }
  .audio-orbit span:nth-child(2) { inset: 10px; }
  .audio-orbit span:nth-child(3) { inset: 21px; }
  .audio-orbit strong { width: 40px; height: 40px; }
  .course-audio-controls { grid-template-columns: 42px minmax(0, 1fr) 68px; gap: 10px; }
  .course-audio-controls.has-regeneration { grid-template-columns: 42px minmax(0, 1fr) 68px; }
  .course-audio-timeline { grid-column: 2 / 4; grid-row: 1; }
  .course-audio-volume { grid-column: 2; grid-row: 2; padding-right: 4px; }
  .course-audio-rate { grid-column: 3; grid-row: 2; width: 68px; }
  .course-audio-regenerate { grid-column: 1; grid-row: 2; justify-self: center; }
  .course-audio-status:not(.visually-hidden) { margin-left: 52px; }
  .context-audio-pair-body { grid-template-columns: 1fr; gap: 14px; }
  .context-audio-pair-voices { justify-content: flex-start; }
  .context-audio-card { grid-template-columns: 1fr; }
  .context-audio-identity { padding-top: 0; }
  .context-audio-group-item-header { grid-template-columns: 1fr; gap: 4px; }
  .context-audio-transcript p { grid-template-columns: 1fr; gap: 4px; }
  .dialogue-sample { grid-template-columns: 1fr; margin-top: -48px; }
  .dialogue-voices { justify-content: flex-start; }
  .critical-note { grid-template-columns: 1fr; gap: 5px; }
  .lesson-footer { align-items: flex-start; flex-direction: column; }
  .section-takeaway { grid-template-columns: 1fr; gap: 5px; }
  .knowledge-options { grid-template-columns: 1fr; }
  .reference-note { display: block; }
  .reference-note strong { display: block; margin-bottom: 5px; }
}

@media (max-width: 480px) {
  .auth-orbit-one { width: 150vw; height: 58vw; }
  .brand { font-size: 1rem; }
  .mobile-menu { font-size: .8rem; }
  .admin-active .mobile-menu { display: none; }
  .admin-metrics { grid-template-columns: 1fr; }
  .admin-metrics article { min-height: 128px; }
}

@media (min-width: 981px) {
  .auth-benefits li { font-size: .9375rem; }
  .auth-benefits span,
  .auth-form label,
  .auth-field > span,
  .auth-mode-prompt,
  .auth-status,
  .auth-privacy { font-size: .875rem; }
  .auth-field input::placeholder { color: var(--muted); }

  .course-progress,
  .account-menu { font-size: .875rem; }
  .account-menu button { min-height: 40px; padding: 8px 13px; font-size: .9375rem; }

  .app-layout { grid-template-columns: 300px minmax(0, 1fr); }
  .sidebar-intro p:last-child,
  .sidebar-note { font-size: .9375rem; }
  .eyebrow,
  .nav-module > p { font-size: .8125rem; }
  .nav-module button { font-size: .9375rem; line-height: 1.4; }
  .lesson-status { width: 26px; height: 26px; font-size: .8125rem; }
  .nav-module button small { font-size: .8125rem; line-height: 1.4; }

  .lesson {
    max-width: 1380px;
    padding: 56px clamp(28px, 3vw, 52px) 80px;
  }
  .lesson-goal div span { font-size: .9375rem; line-height: 1.55; }
  .section-navigation ol {
    grid-template-columns: repeat(var(--section-count, 5), minmax(132px, 1fr));
    min-width: max(760px, calc(var(--section-count, 5) * 138px));
  }
  .section-step-status { font-size: .8125rem; }
  .section-navigation strong { font-size: .875rem; line-height: 1.35; }
  .section-navigation small { font-size: .8125rem; line-height: 1.4; }
  .learning-objectives li,
  .knowledge-feedback,
  .critical-note p { font-size: 1rem; line-height: 1.65; }
  .reference-note { font-size: .9375rem; line-height: 1.6; }

  .audio-transcript summary,
  .dialogue-script summary,
  .context-audio-transcript summary { font-size: .9375rem; }
  .audio-transcript p { font-size: 1rem; line-height: 1.75; }
  .dialogue-script p {
    grid-template-columns: minmax(76px, max-content) 1fr;
    font-size: 1rem;
    line-height: 1.65;
  }
  .context-audio-transcript p { font-size: 1rem; line-height: 1.65; }

  .section-save-status { font-size: .9375rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}