:root {
    --platform-bg: #080b12;
    --platform-panel: #101721;
    --platform-panel-strong: #151e2b;
    --platform-line: #263344;
    --platform-text: #f5f8fb;
    --platform-muted: #9eacba;
    --platform-cyan: #31d6c4;
    --platform-orange: #ff8a24;
    --platform-magenta: #d760ff;
    --platform-green: #5dd39e;
    --platform-yellow: #f1c453;
    --platform-danger: #ff5b67;
    --platform-radius: 8px;
    --platform-max: 1240px;
}

* {
    box-sizing: border-box;
    letter-spacing: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--platform-bg);
    color: var(--platform-text);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

a {
    color: inherit;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    min-height: 84px;
    padding: 7px max(24px, calc((100vw - var(--platform-max)) / 2));
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 28px;
    background: rgba(8, 11, 18, .94);
    border-bottom: 1px solid rgba(49, 214, 196, .18);
    backdrop-filter: blur(18px);
}

.brand {
    min-width: 0;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--platform-text);
    text-decoration: none;
}

.brand-logo {
    display: block;
    object-fit: contain;
}

.brand-logo-wide {
    width: 230px !important;
    height: 69px !important;
    flex: 0 0 230px;
    border: 0;
    border-radius: 0 !important;
    filter: drop-shadow(0 0 14px rgba(49, 214, 196, .2));
}

.brand span {
    min-width: 0;
    display: grid;
    gap: 2px;
}

.brand strong {
    font-size: 17px;
    line-height: 1.1;
}

.brand small {
    max-width: 330px;
    overflow: hidden;
    color: var(--platform-muted);
    font-size: 11px;
    line-height: 1.25;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.site-nav,
.account {
    display: flex;
    align-items: center;
    gap: 8px;
}

.site-nav a {
    padding: 10px 12px;
    color: #cbd5df;
    font-size: 13px;
    font-weight: 700;
    text-decoration: none;
}

.site-nav a:hover,
.site-nav a:focus-visible {
    color: var(--platform-cyan);
}

.site-nav .nav-account {
    border: 1px solid rgba(49, 214, 196, .55);
    border-radius: 6px;
    color: var(--platform-text);
}

.account {
    color: var(--platform-muted);
    font-size: 12px;
}

.account form {
    margin: 0;
}

.icon-button {
    width: 36px;
    height: 36px;
    display: inline-grid;
    place-items: center;
    padding: 0;
    border: 1px solid var(--platform-line);
    border-radius: 6px;
    background: #111925;
    color: var(--platform-text);
    font-weight: 800;
    text-decoration: none;
    cursor: pointer;
}

.icon-button:hover,
.icon-button:focus-visible {
    border-color: var(--platform-cyan);
    color: var(--platform-cyan);
}

.page-shell,
.public-content-shell {
    width: min(var(--platform-max), calc(100% - 48px));
    margin: 0 auto;
    padding: 48px 0 80px;
}

.public-shell {
    width: 100%;
    overflow: hidden;
}

.platform-hero {
    position: relative;
    width: 100%;
    height: min(720px, calc(100svh - 190px));
    min-height: min(580px, calc(100svh - 190px));
    padding: 58px max(24px, calc((100vw - var(--platform-max)) / 2));
    display: flex;
    align-items: center;
    background-color: #060913;
    border-bottom: 1px solid rgba(49, 214, 196, .24);
    isolation: isolate;
}

.platform-hero::before {
    position: absolute;
    inset: 0;
    z-index: 1;
    background: rgba(3, 6, 13, .3);
    content: "";
}

.hero-backdrop {
    position: absolute;
    inset: 0;
    z-index: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
}

.hero-copy {
    position: relative;
    z-index: 2;
    width: min(620px, 58%);
    padding: 10px 0 76px;
    text-shadow: 0 2px 20px rgba(0, 0, 0, .72);
}

.hero-brand-mark,
.login-brand-mark {
    width: 88px;
    height: 88px;
    object-fit: cover;
    border: 1px solid rgba(187, 148, 255, .8);
    border-radius: 8px;
    box-shadow: 0 0 36px rgba(130, 76, 255, .34);
}

.hero-kicker,
.eyebrow {
    margin: 20px 0 8px;
    color: var(--platform-cyan);
    font-size: 11px;
    font-weight: 900;
    text-transform: uppercase;
}

.hero-copy .hero-kicker {
    margin-top: 0;
}

.hero-copy h1 {
    margin: 0;
    font-size: 72px;
    line-height: .98;
    font-weight: 850;
}

.hero-copy > p:not(.hero-kicker) {
    max-width: 600px;
    margin: 24px 0 0;
    color: #dbe3ea;
    font-size: 20px;
    line-height: 1.55;
}

.hero-actions {
    margin-top: 34px;
    display: flex;
    align-items: center;
    gap: 20px;
}

.button-link,
button.primary,
.primary {
    display: inline-flex;
    min-height: 44px;
    align-items: center;
    justify-content: center;
    padding: 11px 18px;
    border: 1px solid var(--platform-cyan);
    border-radius: 6px;
    background: var(--platform-cyan);
    color: #04110f;
    font: inherit;
    font-size: 13px;
    font-weight: 900;
    text-decoration: none;
    cursor: pointer;
}

.button-link:hover,
.button-link:focus-visible,
button.primary:hover,
button.primary:focus-visible {
    background: #6de5d8;
    border-color: #6de5d8;
}

.button-link.secondary,
.secondary.button-link {
    border-color: var(--platform-line);
    background: transparent;
    color: var(--platform-text);
}

.button-link.secondary:hover,
.secondary.button-link:hover {
    border-color: var(--platform-cyan);
    color: var(--platform-cyan);
}

.hero-login {
    padding: 10px 0;
    border-bottom: 1px solid rgba(245, 248, 251, .55);
    color: var(--platform-text);
    font-size: 13px;
    font-weight: 800;
    text-decoration: none;
}

.hero-login:hover,
.hero-login:focus-visible {
    border-color: var(--platform-cyan);
    color: var(--platform-cyan);
}

.hero-signal {
    position: absolute;
    z-index: 2;
    right: max(24px, calc((100vw - var(--platform-max)) / 2));
    bottom: 24px;
    display: grid;
    grid-template-columns: auto auto;
    gap: 4px 12px;
    padding: 14px 16px;
    border-left: 2px solid var(--platform-orange);
    background: rgba(4, 8, 15, .76);
    color: #c9d2db;
    font-size: 11px;
}

.hero-signal span {
    color: var(--platform-orange);
    font-weight: 900;
}

.public-intro,
.band-heading,
.account-invitation,
.page-heading,
.section-title {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 44px;
}

.public-intro {
    width: min(var(--platform-max), calc(100% - 48px));
    margin: 0 auto;
    padding: 76px 0;
    border-bottom: 1px solid var(--platform-line);
}

.public-intro > div,
.band-heading > div,
.account-invitation > div {
    flex: 0 1 500px;
}

.public-intro h2,
.band-heading h2,
.learning-method h2,
.account-invitation h2,
.page-heading h1,
.public-catalog-heading h1,
.public-lesson > header h1 {
    margin: 0;
    font-size: 38px;
    line-height: 1.12;
}

.public-intro > p,
.band-heading > p,
.account-invitation p,
.page-heading p,
.public-catalog-heading > p,
.public-lesson > header > p {
    max-width: 590px;
    margin: 0;
    color: var(--platform-muted);
    font-size: 16px;
    line-height: 1.65;
}

.subject-band,
.open-lessons-band,
.learning-method,
.account-invitation {
    width: min(var(--platform-max), calc(100% - 48px));
    margin: 0 auto;
    padding: 72px 0;
}

.subject-grid,
.cockpit-grid,
.library-school-grid,
.library-subject-grid {
    margin-top: 34px;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 14px;
}

.subject-tile,
.cockpit-tile,
.library-school-tile,
.library-subject-grid > a {
    position: relative;
    min-height: 230px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    overflow: hidden;
    border: 1px solid var(--platform-line);
    border-radius: var(--platform-radius);
    background: var(--platform-panel);
    color: var(--platform-text);
    text-decoration: none;
}

.subject-tile::before,
.library-subject-grid > a::before {
    position: absolute;
    inset: 0 auto 0 0;
    width: 4px;
    background: var(--subject-color);
    content: "";
}

.subject-tile:hover,
.subject-tile:focus-visible,
.cockpit-tile:hover,
.cockpit-tile:focus-visible,
.library-school-tile:hover,
.library-school-tile:focus-visible,
.library-subject-grid > a:hover,
.library-subject-grid > a:focus-visible {
    border-color: var(--subject-color, var(--platform-cyan));
    background: var(--platform-panel-strong);
    transform: translateY(-2px);
}

.subject-tile > span,
.tile-index,
.library-school-tile > span {
    color: var(--subject-color, var(--platform-cyan));
    font-size: 12px;
    font-weight: 900;
}

.subject-tile h3,
.cockpit-tile h2,
.library-school-tile h2,
.library-subject-grid h2 {
    margin: 8px 0;
    font-size: 22px;
}

.subject-tile p,
.cockpit-tile p,
.library-school-tile p,
.library-subject-grid p {
    margin: 0;
    color: var(--platform-muted);
    font-size: 13px;
    line-height: 1.55;
}

.subject-tile > strong,
.cockpit-tile > strong,
.library-school-tile > strong,
.library-subject-grid > a > strong {
    color: var(--subject-color, var(--platform-cyan));
    font-size: 12px;
}

.open-lessons-band {
    border-top: 1px solid var(--platform-line);
}

.open-lesson-list,
.catalog-lessons,
.material-lesson-table,
.compact-class-list {
    margin-top: 30px;
    border-top: 1px solid var(--platform-line);
}

.open-lesson-list > a,
.catalog-lessons > a,
.catalog-lessons > div,
.material-lesson-table > div,
.compact-class-list > a {
    min-height: 108px;
    padding: 20px 8px;
    display: grid;
    grid-template-columns: 54px minmax(0, 1fr) auto;
    align-items: center;
    gap: 20px;
    border-bottom: 1px solid var(--platform-line);
    color: inherit;
    text-decoration: none;
}

.open-lesson-list > a:hover,
.catalog-lessons > a:hover,
.compact-class-list > a:hover {
    background: rgba(49, 214, 196, .045);
}

.open-lesson-list > a > span,
.catalog-lessons > * > span,
.compact-class-list > a > span,
.lesson-no {
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    border: 1px solid var(--lesson-color, var(--subject-color, var(--platform-line)));
    border-radius: 6px;
    color: var(--lesson-color, var(--subject-color, var(--platform-cyan)));
    font-weight: 900;
}

.open-lesson-list h3,
.catalog-lessons h3 {
    margin: 4px 0;
    font-size: 18px;
}

.open-lesson-list small,
.open-lesson-list p,
.catalog-lessons p,
.compact-class-list small,
.material-lesson-table small {
    margin: 0;
    color: var(--platform-muted);
    line-height: 1.45;
}

.open-lesson-list > a > strong,
.catalog-lessons > * > strong,
.catalog-lessons > * > a,
.compact-class-list b {
    color: var(--platform-cyan);
    font-size: 12px;
    font-weight: 900;
}

.learning-method {
    display: grid;
    grid-template-columns: minmax(0, .9fr) minmax(0, 1.4fr);
    gap: 80px;
    border-top: 1px solid var(--platform-line);
}

.method-copy > p:last-child {
    color: var(--platform-muted);
    line-height: 1.65;
}

.learning-method ol {
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    list-style: none;
}

.learning-method li {
    min-height: 170px;
    padding: 20px;
    border-left: 1px solid var(--platform-line);
    border-bottom: 1px solid var(--platform-line);
}

.learning-method li span {
    color: var(--platform-orange);
    font-size: 11px;
    font-weight: 900;
}

.learning-method li strong {
    margin-top: 18px;
    display: block;
    font-size: 17px;
}

.learning-method li p {
    color: var(--platform-muted);
    font-size: 13px;
    line-height: 1.5;
}

.account-invitation {
    margin-bottom: 60px;
    padding-right: 32px;
    padding-left: 32px;
    align-items: center;
    border: 1px solid rgba(49, 214, 196, .38);
    border-radius: var(--platform-radius);
    background: #0d171d;
}

.page-heading {
    margin-bottom: 34px;
}

.page-heading .eyebrow,
.page-heading p {
    margin: 0 0 8px;
}

.cockpit-heading h1 {
    font-size: 42px;
}

.cockpit-stats {
    margin: 0;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    border: 1px solid var(--platform-line);
    border-radius: var(--platform-radius);
    overflow: hidden;
}

.cockpit-stats div {
    padding: 18px 20px;
    border-right: 1px solid var(--platform-line);
}

.cockpit-stats div:last-child {
    border-right: 0;
}

.cockpit-stats dt {
    color: var(--platform-muted);
    font-size: 11px;
    font-weight: 800;
    text-transform: uppercase;
}

.cockpit-stats dd {
    margin: 6px 0 0;
    font-size: 30px;
    font-weight: 850;
}

.cockpit-tile {
    min-height: 300px;
}

.tile-settings { --subject-color: var(--platform-orange); }
.tile-users { --subject-color: var(--platform-cyan); }
.tile-materials { --subject-color: var(--platform-green); }

.cockpit-tile::after {
    position: absolute;
    top: 0;
    right: 0;
    width: 58px;
    height: 4px;
    background: var(--subject-color);
    content: "";
}

.cockpit-lower {
    margin-top: 56px;
    display: grid;
    grid-template-columns: minmax(0, 1.6fr) minmax(280px, .75fr);
    gap: 32px;
}

.section-title h2 {
    margin: 0;
}

.section-title > a {
    color: var(--platform-cyan);
    font-size: 12px;
    font-weight: 800;
}

.development-box,
.archive-notice {
    padding: 26px;
    border: 1px dashed #526070;
    border-radius: var(--platform-radius);
    background: #0d131c;
}

.development-box h2,
.archive-notice h2 {
    margin: 8px 0;
}

.development-box p,
.archive-notice p {
    color: var(--platform-muted);
    line-height: 1.55;
}

.development-box span,
.archive-notice > span {
    color: var(--platform-yellow);
    font-size: 11px;
    font-weight: 900;
}

.public-catalog-heading,
.public-lesson > header {
    max-width: 900px;
    padding: 36px 0 50px;
    border-bottom: 3px solid var(--subject-color);
}

.public-catalog-heading > a,
.public-lesson nav a {
    color: var(--platform-cyan);
    font-size: 12px;
    font-weight: 800;
}

.catalog-chapters,
.material-chapter-list {
    margin-top: 52px;
    display: grid;
    gap: 50px;
}

.catalog-chapters > section,
.material-chapter-list > section {
    padding: 0;
    border: 0;
    background: transparent;
}

.catalog-chapter-title,
.topic-heading,
.material-chapter-list > section > header {
    display: flex;
    align-items: center;
    gap: 16px;
}

.catalog-chapter-title > span,
.topic-heading > span {
    color: var(--subject-color);
    font-size: 12px;
    font-weight: 900;
}

.catalog-chapter-title h2,
.topic-heading h2,
.material-chapter-list h2 {
    margin: 0;
    font-size: 24px;
}

.catalog-lessons .is-locked {
    color: #aeb8c2;
    opacity: .72;
}

.public-lesson nav {
    display: flex;
    gap: 12px;
    color: var(--platform-muted);
    font-size: 12px;
}

.public-topic {
    max-width: 980px;
    padding: 58px 0;
    border-bottom: 1px solid var(--platform-line);
}

.imported-lesson {
    --lesson-reading-width: 920px;
}

.imported-section {
    max-width: var(--lesson-reading-width);
    padding: 48px 0;
    border-bottom: 1px solid var(--platform-line);
}

.imported-section h2 {
    margin: 0 0 20px;
    font-size: 28px;
    line-height: 1.2;
}

.rich-lesson-content {
    color: #d6dee6;
    font-size: 17px;
    line-height: 1.75;
}

.rich-lesson-content table {
    display: block;
    max-width: 100%;
    overflow-x: auto;
    border-collapse: collapse;
}

.rich-lesson-content th,
.rich-lesson-content td {
    padding: 10px 12px;
    border: 1px solid var(--line);
    text-align: left;
    vertical-align: top;
}

.rich-lesson-content img {
    max-width: 100%;
    height: auto;
}

.rich-lesson-content > :first-child {
    margin-top: 0;
}

.rich-lesson-content > :last-child {
    margin-bottom: 0;
}

.rich-lesson-content h3 {
    margin: 30px 0 10px;
    color: var(--platform-text);
    font-size: 20px;
}

.rich-lesson-content a {
    color: var(--platform-cyan);
}

.rich-lesson-content code {
    padding: 2px 5px;
    border: 1px solid rgba(49, 214, 196, .18);
    border-radius: 4px;
    background: #081217;
    color: #8be8dd;
    font-size: .9em;
}

.rich-lesson-content pre,
.imported-diagram pre,
.imported-code pre {
    max-width: 100%;
    overflow: auto;
    border: 1px solid #263b43;
    border-radius: 6px;
    background: #070d12;
    color: #dff9f5;
    font: 14px/1.65 ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    white-space: pre;
}

.rich-lesson-content pre {
    padding: 18px;
}

.rich-lesson-content pre code {
    padding: 0;
    border: 0;
    background: transparent;
}

.rich-lesson-content li + li {
    margin-top: 8px;
}

.imported-life-example {
    padding-right: 28px;
    padding-left: 28px;
    border-left: 3px solid var(--platform-orange);
    background: #12151a;
}

.diagram-canvas {
    max-width: 100%;
    overflow: auto;
}

.diagram-canvas svg {
    max-width: 100%;
    height: auto;
}

.imported-diagram pre {
    padding: 24px;
    color: #a9e9e1;
}

.code-heading {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 24px;
}

.code-heading .eyebrow {
    margin-top: 0;
}

.code-heading > span {
    color: var(--platform-muted);
    font-size: 12px;
    font-weight: 800;
    text-transform: uppercase;
}

.imported-code pre {
    margin: 0;
    padding: 24px;
    border-top: 3px solid var(--subject-color);
}

.task-levels {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    border-top: 1px solid var(--platform-line);
}

.task-levels article {
    min-width: 0;
    padding: 22px;
    border-right: 1px solid var(--platform-line);
    border-bottom: 1px solid var(--platform-line);
}

.task-levels article:last-child {
    border-right: 0;
}

.task-levels article > span {
    color: var(--platform-orange);
    font-size: 11px;
    font-weight: 900;
}

.task-levels h3 {
    margin: 12px 0;
    font-size: 17px;
}

.task-levels .rich-lesson-content {
    color: var(--platform-muted);
    font-size: 14px;
    line-height: 1.6;
}

.imported-errors {
    padding-right: 26px;
    padding-left: 26px;
    border-left: 3px solid var(--platform-danger);
    background: #171014;
}

.import-source-note {
    max-width: var(--lesson-reading-width);
    padding: 28px 0;
    display: flex;
    justify-content: space-between;
    gap: 20px;
    color: var(--platform-muted);
    font-size: 12px;
}

.import-source-note a,
.material-lesson-link {
    color: var(--platform-cyan);
}

.material-lesson-link {
    text-decoration: none;
}

.material-lesson-link:hover,
.material-lesson-link:focus-visible {
    text-decoration: underline;
}

.topic-lead {
    max-width: 780px;
    color: #c8d2dc;
    font-size: 18px;
    line-height: 1.75;
}

.public-fact-grid,
.public-definitions {
    margin-top: 30px;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.public-fact-grid article,
.public-definitions article {
    padding: 20px;
    border-left: 2px solid var(--subject-color);
    background: var(--platform-panel);
}

.public-fact-grid p,
.public-definitions p {
    color: var(--platform-muted);
    font-size: 13px;
    line-height: 1.55;
}

.lesson-account-gate,
.archive-notice {
    margin-top: 58px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 28px;
}

.lesson-account-gate {
    padding: 28px;
    border: 1px solid rgba(49, 214, 196, .36);
    border-radius: var(--platform-radius);
    background: #0c171c;
}

.lesson-account-gate h2 {
    margin: 6px 0;
}

.lesson-account-gate p {
    margin: 0;
    color: var(--platform-muted);
}

.settings-layout {
    display: grid;
    grid-template-columns: 280px minmax(0, 1fr);
    gap: 36px;
}

.settings-nav {
    display: grid;
    align-self: start;
    border-top: 1px solid var(--platform-line);
}

.settings-nav a {
    padding: 18px 4px;
    display: grid;
    grid-template-columns: 32px 1fr;
    gap: 2px 10px;
    border-bottom: 1px solid var(--platform-line);
    text-decoration: none;
}

.settings-nav span {
    grid-row: 1 / span 2;
    color: var(--platform-orange);
    font-weight: 900;
}

.settings-nav small {
    color: var(--platform-muted);
}

.settings-content,
.quick-lesson-form {
    display: grid;
    gap: 18px;
}

.settings-content > section,
.settings-content form > section,
.quick-lesson-form > section {
    padding: 28px;
    border: 1px solid var(--platform-line);
    border-radius: var(--platform-radius);
    background: var(--platform-panel);
}

.settings-content h2,
.quick-lesson-form h2 {
    margin: 8px 0 12px;
}

.settings-content p,
.quick-lesson-form p {
    color: var(--platform-muted);
    line-height: 1.55;
}

.form-grid {
    margin-top: 24px;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px;
}

label {
    display: grid;
    gap: 7px;
    color: #dbe3ea;
    font-size: 12px;
    font-weight: 800;
}

label.wide {
    grid-column: 1 / -1;
}

input,
select,
textarea {
    width: 100%;
    min-height: 44px;
    padding: 10px 12px;
    border: 1px solid #344357;
    border-radius: 5px;
    outline: 0;
    background: #090e16;
    color: var(--platform-text);
    font: inherit;
}

textarea {
    resize: vertical;
}

input:focus,
select:focus,
textarea:focus {
    border-color: var(--platform-cyan);
    box-shadow: 0 0 0 3px rgba(49, 214, 196, .12);
}

.color-field {
    display: flex;
    align-items: center;
    gap: 12px;
}

.color-field input {
    width: 56px;
    min-height: 44px;
    padding: 3px;
}

.visibility-options {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
}

.visibility-options label {
    min-height: 120px;
    padding: 18px;
    display: flex;
    gap: 12px;
    border: 1px solid var(--platform-line);
    border-radius: 6px;
    background: #0b111a;
}

.visibility-options input,
.publish-switch input,
.check input {
    width: 18px;
    height: 18px;
    min-height: 18px;
    flex: 0 0 18px;
}

.visibility-options span {
    display: grid;
    gap: 8px;
}

.visibility-options small {
    color: var(--platform-muted);
    font-weight: 500;
    line-height: 1.45;
}

.publish-switch {
    margin-top: 18px;
    display: flex;
    align-items: center;
}

.form-actions {
    display: flex;
    align-items: center;
    gap: 18px;
}

.form-actions > a {
    color: var(--platform-muted);
}

.library-school-grid,
.library-subject-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.library-school-tile.is-hidden-space {
    --subject-color: var(--platform-magenta);
    border-style: dashed;
}

.library-subject-grid > a.is-archived {
    opacity: .62;
}

.material-chapter-list > section > header {
    justify-content: space-between;
}

.material-chapter-list > section > header > span {
    color: var(--platform-muted);
    font-size: 12px;
}

.material-lesson-table > div {
    grid-template-columns: 52px minmax(0, 1fr) auto auto;
}

.material-lesson-table > div > div {
    display: grid;
    gap: 4px;
}

.access-badge,
.publish-badge {
    padding: 5px 8px;
    border: 1px solid var(--platform-line);
    border-radius: 4px;
    color: var(--platform-muted);
    font-size: 10px;
    font-weight: 900;
    text-transform: uppercase;
}

.access-public,
.publish-badge.is-live {
    border-color: rgba(93, 211, 158, .45);
    color: var(--platform-green);
}

.access-students {
    border-color: rgba(49, 214, 196, .45);
    color: var(--platform-cyan);
}

.login-shell {
    width: min(1120px, calc(100% - 48px));
    min-height: calc(100svh - 76px);
    margin: 0 auto;
    padding: 64px 0;
    display: grid;
    align-content: center;
}

.login-panel {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 420px;
    gap: 72px;
    align-items: center;
}

.login-panel h1 {
    max-width: 640px;
    margin: 8px 0 18px;
    font-size: 46px;
    line-height: 1.08;
}

.login-panel .lead {
    max-width: 610px;
    color: var(--platform-muted);
    font-size: 17px;
    line-height: 1.65;
}

.class-list {
    margin-top: 28px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.class-list span {
    padding: 7px 10px;
    border: 1px solid var(--platform-line);
    border-radius: 4px;
    color: #c8d2dc;
    font-size: 11px;
}

.auth-form {
    padding: 30px;
    display: grid;
    gap: 18px;
    border: 1px solid var(--platform-line);
    border-radius: var(--platform-radius);
    background: var(--platform-panel);
}

.auth-form h2 {
    margin: 0 0 8px;
}

.auth-form .check {
    display: flex;
    align-items: center;
}

.auth-links {
    display: flex;
    justify-content: space-between;
    gap: 16px;
}

.auth-links a,
.login-public-return a {
    color: var(--platform-cyan);
    font-size: 12px;
}

.login-public-return {
    margin: 28px 0 0;
    text-align: center;
}

.flash,
.error-box {
    width: min(var(--platform-max), calc(100% - 48px));
    margin: 18px auto 0;
    padding: 13px 16px;
    border: 1px solid rgba(93, 211, 158, .46);
    border-radius: 6px;
    background: #0e1c19;
    color: var(--platform-green);
}

.error,
.error-box {
    color: #ffabb1;
}

.error-box {
    border-color: rgba(255, 91, 103, .5);
    background: #211014;
}

.empty {
    padding: 32px 0;
    color: var(--platform-muted);
}

.bitek-assistant {
    position: fixed;
    right: 22px;
    bottom: 16px;
    z-index: 1200;
    width: 112px;
    height: 132px;
    pointer-events: none;
}

.bitek-launcher {
    position: absolute;
    right: 0;
    bottom: 0;
    width: 104px;
    height: 124px;
    padding: 0;
    overflow: visible;
    border: 0;
    background: transparent;
    cursor: pointer;
    pointer-events: auto;
    filter: drop-shadow(0 12px 18px rgba(0, 0, 0, .38));
    animation: bitek-float 4.4s ease-in-out infinite;
}

.bitek-launcher img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    object-position: center bottom;
    transition: transform .2s ease, filter .2s ease;
}

.bitek-launcher:hover img,
.bitek-launcher:focus-visible img {
    transform: translateY(-4px) rotate(2deg) scale(1.04);
    filter: brightness(1.08);
}

.bitek-launcher:focus-visible {
    outline: 2px solid var(--platform-cyan);
    outline-offset: 4px;
}

.bitek-panel {
    position: absolute;
    right: 96px;
    bottom: 76px;
    width: 326px;
    padding: 20px;
    border: 1px solid rgba(49, 214, 196, .42);
    border-radius: 8px;
    background: rgba(10, 17, 24, .97);
    box-shadow: 0 22px 56px rgba(0, 0, 0, .5);
    opacity: 0;
    visibility: hidden;
    transform: translate(14px, 10px) scale(.96);
    transform-origin: right bottom;
    transition: opacity .18s ease, transform .18s ease, visibility .18s;
    pointer-events: none;
}

.bitek-assistant[data-open="true"] .bitek-panel {
    opacity: 1;
    visibility: visible;
    transform: translate(0) scale(1);
    pointer-events: auto;
}

.bitek-panel header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 16px;
    padding-bottom: 13px;
    border-bottom: 1px solid var(--platform-line);
}

.bitek-panel h2 {
    margin: 3px 0 0;
    font-size: 23px;
}

.bitek-panel .eyebrow {
    margin: 0;
}

.bitek-close,
.bitek-controls button {
    display: inline-grid;
    place-items: center;
    border: 1px solid var(--platform-line);
    border-radius: 6px;
    color: #f5f8fa;
    background: #121c25;
    cursor: pointer;
}

.bitek-close {
    width: 34px;
    height: 34px;
    font-size: 24px;
    line-height: 1;
}

.bitek-message {
    min-height: 58px;
    margin: 17px 0;
    color: #c8d4dc;
    font-size: 14px;
    line-height: 1.55;
}

.bitek-controls {
    display: grid;
    grid-template-columns: repeat(3, 44px);
    gap: 8px;
}

.bitek-controls button {
    width: 44px;
    height: 40px;
    color: var(--platform-cyan);
    font-size: 17px;
}

.bitek-close:hover,
.bitek-close:focus-visible,
.bitek-controls button:hover,
.bitek-controls button:focus-visible {
    border-color: var(--platform-cyan);
    background: #172a31;
    outline: none;
}

.bitek-assistant.is-speaking .bitek-launcher {
    animation: bitek-speaking .72s ease-in-out infinite alternate;
}

.bitek-assistant.is-paused .bitek-launcher {
    animation-play-state: paused;
    opacity: .82;
}

.bitek-reading-active {
    border-radius: 4px;
    outline: 2px solid rgba(49, 214, 196, .6);
    outline-offset: 5px;
    background: rgba(49, 214, 196, .08);
}

@keyframes bitek-float {
    0%, 100% { transform: translateY(0) rotate(-1deg); }
    50% { transform: translateY(-8px) rotate(1deg); }
}

@keyframes bitek-speaking {
    from { transform: translateY(0) rotate(-2deg) scale(1); }
    to { transform: translateY(-5px) rotate(2deg) scale(1.025); }
}

@media (max-width: 1000px) {
    .site-header {
        gap: 14px;
    }

    .site-nav a:not(.nav-account) {
        display: none;
    }

    .account > span {
        display: none;
    }

    .subject-grid,
    .cockpit-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .cockpit-grid > :last-child {
        grid-column: 1 / -1;
    }

    .learning-method,
    .cockpit-lower,
    .settings-layout,
    .login-panel {
        grid-template-columns: 1fr;
    }

    .settings-nav {
        grid-template-columns: repeat(3, minmax(0, 1fr));
        border: 1px solid var(--platform-line);
    }

    .settings-nav a {
        border-right: 1px solid var(--platform-line);
        border-bottom: 0;
    }

    .login-panel {
        gap: 38px;
    }
}

@media (max-width: 720px) {
    .bitek-assistant {
        right: 8px;
        bottom: 8px;
        width: 88px;
        height: 110px;
    }

    .bitek-launcher {
        width: 84px;
        height: 104px;
    }

    .bitek-panel {
        position: fixed;
        right: 12px;
        bottom: 96px;
        width: min(326px, calc(100vw - 24px));
    }

    .site-header {
        min-height: 68px;
        padding: 8px 16px;
    }

    .brand-logo-wide {
        width: 154px !important;
        height: 58px !important;
        flex-basis: 154px;
    }

    .brand small,
    .site-nav,
    .account .pwa-header-install,
    .account .push-toggle,
    .account .pwa-header-hint {
        display: none;
    }

    .page-shell,
    .public-content-shell,
    .login-shell {
        width: min(100% - 32px, var(--platform-max));
        padding-top: 32px;
    }

    .platform-hero {
        min-height: calc(100svh - 160px);
        height: auto;
        padding: 42px 20px 108px;
        align-items: end;
    }

    .hero-backdrop {
        object-position: right center;
    }

    .platform-hero::before {
        background: rgba(3, 6, 13, .28);
    }

    .hero-copy {
        width: 100%;
        padding: 0;
    }

    .hero-copy h1,
    .login-panel h1 {
        font-size: 42px;
    }

    .hero-copy > p:not(.hero-kicker) {
        font-size: 16px;
    }

    .hero-signal {
        right: 20px;
        bottom: 18px;
        left: 20px;
        grid-template-columns: auto 1fr auto 1fr auto 1fr;
        overflow: hidden;
    }

    .public-intro,
    .subject-band,
    .open-lessons-band,
    .learning-method,
    .account-invitation {
        width: calc(100% - 32px);
        padding-top: 48px;
        padding-bottom: 48px;
    }

    .public-intro,
    .band-heading,
    .account-invitation,
    .page-heading,
    .section-title,
    .lesson-account-gate,
    .archive-notice {
        align-items: flex-start;
        flex-direction: column;
        gap: 18px;
    }

    .public-intro h2,
    .band-heading h2,
    .learning-method h2,
    .account-invitation h2,
    .page-heading h1,
    .public-catalog-heading h1,
    .public-lesson > header h1,
    .cockpit-heading h1 {
        font-size: 30px;
    }

    .subject-grid,
    .cockpit-grid,
    .library-school-grid,
    .library-subject-grid,
    .public-fact-grid,
    .public-definitions,
    .form-grid,
    .visibility-options {
        grid-template-columns: 1fr;
    }

    .task-levels {
        grid-template-columns: 1fr;
    }

    .task-levels article {
        border-right: 0;
    }

    .imported-section {
        padding: 36px 0;
    }

    .imported-life-example,
    .imported-errors {
        padding-right: 18px;
        padding-left: 18px;
    }

    .rich-lesson-content {
        font-size: 16px;
    }

    .cockpit-grid > :last-child,
    label.wide {
        grid-column: auto;
    }

    .subject-tile,
    .cockpit-tile,
    .library-school-tile,
    .library-subject-grid > a {
        min-height: 210px;
    }

    .open-lesson-list > a,
    .catalog-lessons > a,
    .catalog-lessons > div,
    .compact-class-list > a {
        grid-template-columns: 46px minmax(0, 1fr);
        gap: 12px;
    }

    .open-lesson-list > a > strong,
    .catalog-lessons > * > strong,
    .catalog-lessons > * > a,
    .compact-class-list b {
        grid-column: 2;
    }

    .learning-method {
        gap: 30px;
    }

    .learning-method ol {
        grid-template-columns: 1fr;
    }

    .cockpit-stats {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .cockpit-stats div:nth-child(2) {
        border-right: 0;
    }

    .cockpit-stats div:nth-child(-n+2) {
        border-bottom: 1px solid var(--platform-line);
    }

    .settings-nav {
        grid-template-columns: 1fr;
    }

    .settings-nav a {
        border-right: 0;
        border-bottom: 1px solid var(--platform-line);
    }

    .material-lesson-table > div {
        min-height: auto;
        grid-template-columns: 42px minmax(0, 1fr);
    }

    .material-lesson-table .access-badge,
    .material-lesson-table .publish-badge {
        grid-column: 2;
        justify-self: start;
    }

    .auth-form,
    .settings-content > section,
    .settings-content form > section,
    .quick-lesson-form > section {
        padding: 22px 18px;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    * {
        transition: none !important;
    }

    .bitek-launcher {
        animation: none !important;
    }
}

.catalog-grade{margin:34px 0 4px;padding-bottom:8px;border-bottom:2px solid var(--subject-color,var(--platform-cyan));font-size:1.5rem}
.catalog-review{opacity:.6}