:root {
  --brand-logo: url("../assets/logo_white.png");
  --bg: #f3efe7;
  --bg-accent: #ebe2d3;
  --surface: rgba(255, 252, 246, 0.82);
  --surface-strong: #fffaf0;
  --surface-muted: #ebe4d6;
  --text: #1d2430;
  --muted: #6e7787;
  --border: rgba(30, 38, 50, 0.12);
  --accent: #165bd8;
  --accent-strong: #0f49ad;
  --accent-soft: rgba(22, 91, 216, 0.12);
  --success: #23755a;
  --success-soft: rgba(35, 117, 90, 0.12);
  --warn: #b76618;
  --warn-soft: rgba(183, 102, 24, 0.12);
  --danger: #b34731;
  --danger-soft: rgba(179, 71, 49, 0.12);
  --shadow: 0 24px 60px -32px rgba(28, 34, 46, 0.35);
  --shadow-soft: 0 18px 40px -30px rgba(28, 34, 46, 0.3);
  --radius-lg: 28px;
  --radius-md: 20px;
  --radius-sm: 14px;
}

[data-theme="dark"] {
  --brand-logo: url("../assets/logo_dark.png");
  --bg: #101317;
  --bg-accent: #191f28;
  --surface: rgba(24, 29, 36, 0.84);
  --surface-strong: #1b222c;
  --surface-muted: #222a35;
  --text: #f4efe3;
  --muted: #a6adbb;
  --border: rgba(241, 233, 215, 0.1);
  --accent: #87b7ff;
  --accent-strong: #639cff;
  --accent-soft: rgba(135, 183, 255, 0.14);
  --success: #7bc7a5;
  --success-soft: rgba(123, 199, 165, 0.14);
  --warn: #efb36d;
  --warn-soft: rgba(239, 179, 109, 0.14);
  --danger: #f1937d;
  --danger-soft: rgba(241, 147, 125, 0.16);
  --shadow: 0 24px 60px -32px rgba(0, 0, 0, 0.7);
  --shadow-soft: 0 18px 40px -30px rgba(0, 0, 0, 0.65);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  min-height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Space Grotesk", system-ui, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(22, 91, 216, 0.14), transparent 34%),
    radial-gradient(circle at bottom right, rgba(183, 102, 24, 0.1), transparent 28%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-accent) 100%);
  transition: background 180ms ease, color 180ms ease;
}

form {
  margin: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
textarea {
  font: inherit;
}

img {
  max-width: 100%;
  display: block;
}

.is-hidden {
  display: none !important;
}

.stack,
.stack-sm,
.stack-lg {
  display: grid;
}

.stack {
  gap: 1rem;
}

.stack-sm {
  gap: 0.5rem;
}

.stack-lg {
  gap: 1.5rem;
}

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.section-kicker::before {
  content: "";
  width: 1.6rem;
  height: 1px;
  background: currentColor;
  opacity: 0.6;
}

.flash-stack {
  position: fixed;
  top: 1rem;
  left: 50%;
  z-index: 40;
  width: min(640px, calc(100% - 2rem));
  transform: translateX(-50%);
  display: grid;
  gap: 0.75rem;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: 0.9rem;
  min-width: 0;
}

.brand-link__mark {
  width: clamp(8.75rem, 11vw, 10.5rem);
  aspect-ratio: 11029 / 2759;
  flex: none;
  background: center / contain no-repeat var(--brand-logo);
}

.brand-link__text {
  display: grid;
  gap: 0.2rem;
  line-height: 1.05;
}

.brand-link__text small {
  color: var(--muted);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.icon-button,
.button {
  border: 1px solid transparent;
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  transition:
    background 140ms ease,
    border-color 140ms ease,
    color 140ms ease,
    transform 140ms ease;
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1rem;
  border-color: var(--border);
  background: rgba(255, 255, 255, 0.06);
}

summary.icon-button {
  list-style: none;
}

summary.icon-button::-webkit-details-marker {
  display: none;
}

.icon-button:hover,
.button:hover {
  transform: translateY(-1px);
}

.icon-button:disabled,
.button:disabled {
  cursor: default;
  opacity: 0.6;
  transform: none;
}

.button {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 0.55rem;
  padding: 0.9rem 1.3rem;
  font-weight: 500;
}

.button--primary {
  background: var(--accent);
  color: #fff;
}

.button--primary:hover {
  background: var(--accent-strong);
}

.button--secondary {
  background: var(--surface-strong);
  border-color: var(--border);
}

.button--ghost {
  border-color: var(--border);
  color: var(--muted);
}

.button--danger {
  border-color: transparent;
  background: var(--danger-soft);
  color: var(--danger);
}

.button--full {
  width: 100%;
}

.button--icon {
  min-width: 2.8rem;
  padding-inline: 0.8rem;
}

.desktop-only {
  display: inline-flex;
}

.mobile-only {
  display: none;
}

.site-shell,
.auth-shell {
  min-height: 100vh;
}

.site-header,
.auth-topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: rgba(245, 239, 229, 0.7);
  border-bottom: 1px solid var(--border);
}

[data-theme="dark"] .site-header,
[data-theme="dark"] .auth-topbar {
  background: rgba(16, 19, 23, 0.78);
}

.site-header__inner,
.auth-topbar__inner {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.18);
}

.nav-link {
  padding: 0.65rem 1rem;
  border-radius: 999px;
  color: var(--muted);
}

.nav-link.is-active,
.nav-link:hover {
  background: var(--surface-strong);
  color: var(--text);
}

.site-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.site-actions > form,
.auth-topbar__inner > form {
  margin: 0;
}

.profile-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
  padding: 0.45rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.22);
}

.profile-chip__avatar {
  width: 2.3rem;
  height: 2.3rem;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent) 0%, #1f7fdf 100%);
  color: #fff;
  font-weight: 700;
}

.profile-chip__meta {
  display: grid;
  min-width: 0;
}

.profile-chip__meta strong,
.profile-chip__meta small {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.profile-chip__meta small {
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.68rem;
}

.mobile-nav {
  display: none;
}

.mobile-menu {
  display: none;
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto 1rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
  box-shadow: var(--shadow-soft);
  gap: 0.75rem;
}

.mobile-nav[open] .mobile-menu {
  display: grid;
}

.page-shell {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
  display: grid;
  gap: 1.5rem;
}

.page-hero,
.panel,
.spotlight-card,
.video-card,
.auth-card,
.mini-panel,
.stat-card {
  border: 1px solid var(--border);
  background: var(--surface);
  box-shadow: var(--shadow-soft);
}

.page-hero,
.auth-card {
  border-radius: var(--radius-lg);
}

.panel,
.spotlight-card,
.video-card,
.mini-panel,
.stat-card {
  border-radius: var(--radius-md);
}

.page-hero {
  display: grid;
  grid-template-columns: 1.4fr minmax(220px, 0.8fr);
  gap: 1.25rem;
  padding: 2rem;
  overflow: hidden;
  position: relative;
}

.page-hero::after {
  content: "";
  position: absolute;
  inset: auto -8% -40% auto;
  width: 18rem;
  height: 18rem;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(22, 91, 216, 0.18), transparent 70%);
  pointer-events: none;
}

.page-hero--tight {
  grid-template-columns: 1fr;
}

.page-hero h1,
.auth-hero h1,
.auth-card__title {
  margin: 0;
  line-height: 0.98;
  letter-spacing: -0.04em;
}

.page-hero h1,
.auth-hero h1 {
  font-size: clamp(2.4rem, 5vw, 4.5rem);
}

.auth-card__title {
  font-size: clamp(1.6rem, 3vw, 2.3rem);
}

.page-hero p,
.auth-hero p,
.auth-card__subtitle,
.panel__header p,
.hero-note,
.stat-card p,
.mini-panel p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: flex-end;
  gap: 0.75rem;
}

.hero-note {
  align-self: end;
  padding: 1rem 1.2rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-strong);
}

.stat-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.stat-card {
  padding: 1.2rem 1.3rem;
}

.stat-card span,
.mini-panel span {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.stat-card strong,
.mini-panel strong {
  display: block;
  margin-top: 0.6rem;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1;
  letter-spacing: -0.04em;
}

.panel,
.spotlight-card,
.auth-card,
.video-card {
  padding: 1.4rem;
}

.panel--compact {
  padding: 1rem;
}

.panel__header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.2rem;
}

.panel__header h2 {
  margin: 0.35rem 0 0;
  font-size: 1.55rem;
  letter-spacing: -0.03em;
}

.course-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.course-card {
  display: grid;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.course-card__media,
.spotlight-card__media {
  position: relative;
  min-height: 10rem;
  border-radius: calc(var(--radius-md) - 6px);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(22, 91, 216, 0.2), rgba(183, 102, 24, 0.14)),
    linear-gradient(135deg, #223147, #66543a);
}

.course-card__media img,
.spotlight-card__media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-card__body {
  display: grid;
  gap: 0.55rem;
}

.course-card__body h3,
.spotlight-card__content h2,
.editor-module__header h3 {
  margin: 0;
  letter-spacing: -0.03em;
}

.course-card__body p,
.spotlight-card__content p,
.lesson-row small,
.course-summary p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.course-card__footer,
.inline-form,
.form-grid,
.course-summary__meta,
.course-summary__actions,
.lesson-actions,
.course-badges,
.course-meta,
.outline-group,
.editor-module__header {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.course-card__footer {
  align-items: center;
  justify-content: space-between;
}

.item-order,
.editor-module__actions,
.editor-lesson__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 1.9rem;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.8rem;
}

.badge--success {
  background: var(--success-soft);
  color: var(--success);
}

.badge--warn {
  background: var(--warn-soft);
  color: var(--warn);
}

.badge--danger {
  background: var(--danger-soft);
  color: var(--danger);
}

.progress {
  display: grid;
  gap: 0.45rem;
}

.progress small {
  color: var(--muted);
}

.progress__bar {
  width: 100%;
  height: 0.5rem;
  border-radius: 999px;
  background: var(--surface-muted);
  overflow: hidden;
}

.progress__bar span {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--accent), var(--success));
}

.spotlight-card {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(260px, 0.9fr);
  gap: 1rem;
}

.spotlight-card__content {
  display: grid;
  align-content: start;
  gap: 0.8rem;
}

.spotlight-card__content h2 {
  font-size: clamp(2rem, 4vw, 3.2rem);
}

.catalog-overview {
  display: grid;
  gap: 1rem;
  padding: 1.1rem 1.2rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background:
    radial-gradient(circle at top right, color-mix(in srgb, var(--accent) 18%, transparent), transparent 40%),
    linear-gradient(180deg, color-mix(in srgb, var(--surface-strong) 94%, var(--accent-soft)), var(--surface));
}

.catalog-overview__copy {
  display: grid;
  gap: 0.45rem;
}

.catalog-overview__copy h2 {
  margin: 0;
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  letter-spacing: -0.04em;
}

.catalog-overview__copy p,
.catalog-guide__card p,
.catalog-highlight__note p,
.catalog-card__hint {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.catalog-guide {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.catalog-guide__card {
  display: grid;
  gap: 0.55rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface);
}

.catalog-guide__card span {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
}

.catalog-guide__card strong,
.catalog-card__body h3 {
  margin: 0;
  letter-spacing: -0.03em;
}

.catalog-highlight {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(300px, 0.95fr);
  gap: 1rem;
  padding: 1.2rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
  box-shadow: var(--shadow-soft);
}

.catalog-highlight__copy {
  display: grid;
  align-content: start;
  gap: 0.85rem;
}

.catalog-highlight__copy h2 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3rem);
  letter-spacing: -0.05em;
}

.catalog-highlight__aside {
  display: grid;
  gap: 0.85rem;
}

.catalog-highlight__media {
  position: relative;
  min-height: 15rem;
  border-radius: var(--radius-sm);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(22, 91, 216, 0.2), rgba(183, 102, 24, 0.14)),
    linear-gradient(135deg, #223147, #66543a);
}

.catalog-highlight__media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.catalog-highlight__note {
  display: grid;
  gap: 0.35rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
}

.catalog-highlight__note strong {
  margin: 0;
  letter-spacing: -0.02em;
}

.catalog-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.catalog-card {
  display: grid;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.catalog-card__body {
  display: grid;
  gap: 0.55rem;
}

.catalog-card__body p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.catalog-card__footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.course-guide {
  margin-top: -0.1rem;
}

.course-module-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.course-module-card {
  display: grid;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
}

.course-module-card__head {
  display: grid;
  gap: 0.8rem;
}

.course-module-card__head h3 {
  margin: 0.35rem 0 0;
  font-size: clamp(1.3rem, 2.5vw, 1.8rem);
  letter-spacing: -0.04em;
}

.course-module-card__head p {
  margin: 0.45rem 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.course-module-card__list {
  display: grid;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: color-mix(in srgb, var(--surface) 92%, transparent);
}

.course-layout,
.lesson-layout,
.admin-layout {
  display: grid;
  gap: 1.5rem;
}

.course-layout,
.lesson-layout {
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.75fr);
  align-items: start;
}

.admin-layout {
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.05fr);
}

.course-summary__cover {
  min-height: 12rem;
  border-radius: var(--radius-sm);
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(22, 91, 216, 0.18), rgba(183, 102, 24, 0.14)),
    linear-gradient(135deg, #223147, #66543a);
}

.course-summary__cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-summary__title {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.3rem);
  line-height: 0.98;
  letter-spacing: -0.05em;
}

.course-summary__meta,
.course-summary__actions {
  align-items: center;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  color: var(--muted);
}

.back-link:hover {
  color: var(--text);
}

.module-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-strong);
  overflow: hidden;
}

.module-card > summary {
  list-style: none;
  cursor: pointer;
  padding: 1rem 1.1rem;
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 1rem;
}

.module-card > summary::-webkit-details-marker {
  display: none;
}

.module-card > summary strong {
  display: block;
  font-size: 1.05rem;
}

.module-card > summary small {
  color: var(--muted);
}

.module-card[open] > summary {
  border-bottom: 1px solid var(--border);
}

.module-card__lessons {
  display: grid;
}

.lesson-row {
  display: grid;
  gap: 0.15rem;
  padding: 0.95rem 1.1rem;
  border-bottom: 1px solid var(--border);
}

.lesson-row:last-child {
  border-bottom: 0;
}

.lesson-row strong {
  font-size: 0.98rem;
}

.lesson-row small {
  font-size: 0.84rem;
}

.lesson-row:hover {
  background: var(--accent-soft);
}

.lesson-row.is-current {
  background: var(--accent-soft);
}

.lesson-row.is-locked {
  cursor: default;
  opacity: 0.75;
}

.lesson-row.is-completed strong {
  color: var(--success);
}

.video-card {
  overflow: hidden;
}

.video-frame {
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: #000;
}

.video-frame iframe {
  width: 100%;
  height: 100%;
  border: 0;
}

.lesson-headline h1 {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: -0.05em;
}

.lesson-headline p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.lesson-actions {
  margin-top: 1rem;
}

.notice {
  padding: 0.9rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface-strong);
  color: var(--text);
  line-height: 1.5;
}

.notice--error {
  border-color: rgba(179, 71, 49, 0.24);
  background: var(--danger-soft);
  color: var(--danger);
}

.notice--success {
  border-color: rgba(35, 117, 90, 0.24);
  background: var(--success-soft);
  color: var(--success);
}

.field {
  display: grid;
  gap: 0.45rem;
}

.field span {
  font-size: 0.9rem;
  font-weight: 500;
}

.field input,
.field textarea {
  width: 100%;
  padding: 0.95rem 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-strong);
  color: var(--text);
}

.field input:focus,
.field textarea:focus {
  outline: 2px solid color-mix(in srgb, var(--accent) 35%, transparent);
  border-color: color-mix(in srgb, var(--accent) 55%, transparent);
}

.field--grow {
  flex: 1 1 18rem;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.inline-form {
  align-items: end;
}

.checkbox-row {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--muted);
}

.auth-grid {
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(340px, 0.9fr);
  gap: 1.5rem;
  align-items: stretch;
}

.auth-hero {
  display: grid;
  align-content: center;
  gap: 1rem;
  padding: 2rem 0;
}

.auth-hero__stack {
  display: grid;
  gap: 0.9rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.auth-card {
  padding: 1.8rem;
  align-self: center;
}

.auth-footer {
  margin: 0;
  color: var(--muted);
}

.auth-footer a {
  color: var(--accent);
}

.mini-panel {
  padding: 1rem;
}

.mini-panel strong {
  font-size: 1.15rem;
}

.loading-box {
  display: grid;
  place-items: center;
  min-height: 8rem;
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border);
  color: var(--muted);
}

.thumbnail-preview {
  max-width: 360px;
  aspect-ratio: 16 / 9;
  margin: 0 0 1rem;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border);
  background: var(--surface-strong);
  display: flex;
  align-items: center;
  justify-content: center;
}

.thumbnail-preview img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.thumbnail-preview--empty {
  color: var(--muted);
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border-style: dashed;
}

.empty-state {
  display: grid;
  gap: 0.8rem;
  justify-items: start;
}

.empty-state h3 {
  margin: 0;
  font-size: 1.35rem;
  letter-spacing: -0.03em;
}

.empty-state p {
  margin: 0;
  color: var(--muted);
}

.outline-group {
  justify-content: space-between;
}

.editor-overview {
  display: grid;
  gap: 1rem;
  margin-bottom: 1.1rem;
  padding: 1rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background:
    radial-gradient(circle at top right, color-mix(in srgb, var(--accent) 18%, transparent), transparent 38%),
    linear-gradient(180deg, color-mix(in srgb, var(--surface-strong) 92%, var(--accent-soft)), var(--surface));
}

.editor-overview__copy {
  display: grid;
  gap: 0.45rem;
}

.editor-overview__copy h3 {
  margin: 0;
  font-size: 1.35rem;
  letter-spacing: -0.03em;
}

.editor-overview__copy p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.editor-list__label {
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.editor-module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}

.editor-module-card {
  display: grid;
  gap: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background:
    radial-gradient(circle at top right, color-mix(in srgb, var(--accent) 15%, transparent), transparent 42%),
    linear-gradient(180deg, color-mix(in srgb, var(--surface-strong) 94%, var(--accent-soft)), var(--surface));
  padding: 1rem;
}

.editor-module-card__head {
  display: grid;
  gap: 0.85rem;
}

.editor-module-card__head h3,
.editor-modal__header h3 {
  margin: 0.35rem 0 0;
  font-size: clamp(1.45rem, 3vw, 2rem);
  letter-spacing: -0.04em;
}

.editor-module-card__head p,
.editor-modal__header p {
  margin: 0.45rem 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.editor-module-card__actions,
.editor-module-card__cta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.75rem;
}

.editor-module-card__actions {
  justify-content: space-between;
  padding-top: 0.25rem;
  border-top: 1px solid var(--border);
}

.editor-modal {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: grid;
  justify-items: end;
  padding: 1rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 160ms ease;
}

.editor-modal:target {
  opacity: 1;
  pointer-events: auto;
}

.editor-modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(16, 19, 23, 0.44);
  backdrop-filter: blur(6px);
}

.editor-modal__panel {
  position: relative;
  width: min(920px, 100%);
  max-height: calc(100vh - 2rem);
  overflow: auto;
  display: grid;
  gap: 1rem;
  padding: 1.2rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface-strong);
  box-shadow: var(--shadow);
}

.editor-modal__header {
  display: flex;
  flex-wrap: wrap;
  align-items: start;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.editor-modal__body {
  display: grid;
  gap: 1rem;
}

.editor-modal__section {
  display: grid;
  gap: 0.85rem;
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
}

.editor-modal__section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.editor-lesson-stack {
  display: grid;
  gap: 0.85rem;
}

.editor-lesson-card {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--surface-strong);
  display: grid;
  gap: 0.85rem;
}

.editor-lesson__head {
  display: flex;
  flex-wrap: wrap;
  align-items: start;
  justify-content: space-between;
  gap: 1rem;
}

.editor-lesson__meta {
  display: grid;
  gap: 0.18rem;
  flex: 1 1 20rem;
}

.editor-lesson__meta small {
  color: var(--muted);
  word-break: break-word;
}

.editor-empty {
  padding: 1rem;
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--surface) 92%, transparent);
}

.editor-drawer {
  display: grid;
  gap: 0.7rem;
}

.editor-drawer > summary {
  list-style: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: fit-content;
}

.editor-drawer > summary::-webkit-details-marker {
  display: none;
}

.editor-drawer__panel {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: color-mix(in srgb, var(--surface-strong) 88%, var(--accent-soft));
  box-shadow: var(--shadow-soft);
}

.editor-drawer--inline,
.editor-drawer--nested {
  width: 100%;
}

.editor-drawer--compact {
  align-content: start;
}

.editor-drawer--nested > summary {
  width: auto;
}

@media (max-width: 1080px) {
  .course-grid,
  .catalog-grid,
  .course-module-grid,
  .stat-grid,
  .auth-hero__stack,
  .catalog-guide,
  .form-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .course-layout,
  .lesson-layout,
  .admin-layout,
  .catalog-highlight,
  .spotlight-card,
  .auth-grid,
  .page-hero {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    justify-content: flex-start;
  }

  .editor-modal {
    padding: 0.6rem;
  }

  .editor-modal__panel {
    max-height: calc(100vh - 1.2rem);
  }
}

@media (max-width: 820px) {
  .desktop-only,
  .site-nav {
    display: none;
  }

  .mobile-only {
    display: inline-flex;
  }

   .mobile-nav.mobile-only {
    display: block;
   }
}

@media (max-width: 720px) {
  .page-shell,
  .auth-grid {
    width: min(100% - 1.2rem, 100%);
  }

  .course-grid,
  .catalog-grid,
  .course-module-grid,
  .stat-grid,
  .auth-hero__stack,
  .catalog-guide,
  .form-grid {
    grid-template-columns: 1fr;
  }

  .page-hero,
  .panel,
  .spotlight-card,
  .video-card,
  .auth-card {
    padding: 1.1rem;
  }

  .site-header__inner,
  .auth-topbar__inner {
    width: min(100% - 1.2rem, 100%);
  }

  .brand-link__text small {
    display: none;
  }

  .inline-form {
    flex-direction: column;
    align-items: stretch;
  }
}