:root {
  --milk: #fbfaf7;
  --text-primary: #292929;
  --text-secondary: #5f5e5b;
  --text-soft: #81807f;
  --line: #b4b3b1;
  --scarlet: #ff2400;
  --green: #2f7d57;
  --amber: #ffae42;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  min-height: 100svh;
  overflow: hidden;
  background: var(--milk);
  color: var(--text-primary);
  font-family: "Urbanist", "Helvetica Neue", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

button,
input {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

.app {
  position: relative;
  min-height: 100svh;
}

.page {
  position: fixed;
  inset: 0;
  z-index: 1;
  visibility: hidden;
  overflow: hidden;
  opacity: 0;
  filter: blur(14px);
  pointer-events: none;
  transition: opacity 0.75s cubic-bezier(.4, 0, .2, 1), filter 0.75s cubic-bezier(.4, 0, .2, 1), visibility 0s linear 0.75s;
}

.page.is-active {
  visibility: visible;
  opacity: 1;
  filter: blur(0);
  pointer-events: auto;
  transition-delay: 0s;
}

.page.is-leaving {
  opacity: 0;
  filter: blur(12px);
}

.service-label {
  margin: 0;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: clamp(0.75rem, 1vw, 0.9rem);
  font-weight: 500;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

.page-label,
.splash-label {
  position: absolute;
  top: max(28px, env(safe-area-inset-top));
  left: max(28px, env(safe-area-inset-left));
}

.splash {
  position: fixed;
  inset: 0;
  z-index: 20;
  overflow: hidden;
  background: var(--milk);
  pointer-events: none;
  opacity: 1;
  visibility: visible;
  transition: opacity 1s cubic-bezier(.4, 0, .2, 1), visibility 0s linear 1s;
}

.splash.is-gone {
  z-index: -1;
  opacity: 0;
  visibility: hidden;
}

.splash-label {
  opacity: 0;
  animation: splash-label 3.5s cubic-bezier(.4, 0, .2, 1) 0.5s forwards;
}

.splash-word {
  position: absolute;
  top: 50%;
  left: 50%;
  margin: 0;
  white-space: nowrap;
  transform: translate(-50%, -50%);
  font-size: clamp(3.25rem, 12vw, 9rem);
  font-weight: 700;
  letter-spacing: -0.075em;
  line-height: 0.9;
  opacity: 0;
  filter: blur(18px);
}

.splash-name {
  animation: splash-name 1.8s cubic-bezier(.4, 0, .2, 1) 0.5s forwards;
}

.splash-rko {
  font-weight: 900;
  animation: splash-rko 2s cubic-bezier(.4, 0, .2, 1) 2s forwards;
}

.auth-page {
  z-index: 5;
  display: grid;
  place-items: center;
  padding: max(74px, env(safe-area-inset-top)) max(20px, env(safe-area-inset-right)) max(28px, env(safe-area-inset-bottom)) max(20px, env(safe-area-inset-left));
}

.auth-form {
  position: relative;
  z-index: 2;
  display: grid;
  width: min(100%, 430px);
  min-height: 410px;
  align-content: center;
  gap: 22px;
  padding: 34px 46px 30px;
  pointer-events: auto;
  transition: opacity 0.7s ease, filter 0.7s ease, transform 0.7s ease;
}

.auth-page.is-active,
.auth-page.is-active .auth-fields,
.auth-page.is-active .field,
.auth-page.is-active input {
  pointer-events: auto;
}

.auth-form.is-authenticated .submit-button {
  opacity: 0;
  filter: blur(5px);
  pointer-events: none;
  transition-duration: 0.3s, 0.3s, 0.18s;
}

.auth-form.is-success {
  opacity: 0;
  filter: blur(22px);
  transform: scale(0.985);
  pointer-events: none;
}

.auth-title,
.submit-button {
  margin: 0;
  color: var(--text-primary);
  font-size: 1.55rem;
  font-weight: 900;
  letter-spacing: 0.04em;
}

.auth-title {
  justify-self: center;
  transition: opacity 0.75s ease, filter 0.75s ease;
}

.auth-form.is-ready .auth-title {
  opacity: 0;
  filter: blur(5px);
}

.auth-fields {
  display: grid;
  gap: 20px;
  transition: opacity 0.45s ease, filter 0.45s ease, transform 0.45s ease;
}

.field {
  position: relative;
  display: grid;
}

.field input {
  position: relative;
  z-index: 1;
  width: 100%;
  min-height: 50px;
  padding: 0 42px;
  border: 0;
  border-bottom: 1px solid var(--line);
  border-radius: 0;
  outline: 0;
  background: transparent;
  color: var(--text-primary);
  caret-color: var(--text-primary);
  font-size: 1.08rem;
  font-weight: 700;
  letter-spacing: 0.025em;
  text-align: center;
  touch-action: manipulation;
  transition: border-color 0.2s ease;
}

.field input::placeholder {
  color: var(--text-secondary);
  opacity: 1;
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: 0.92rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  transition: opacity 0.18s ease;
}

.field input:focus {
  border-color: var(--text-primary);
}

.field input:focus::placeholder {
  opacity: 0;
}

.eye-button {
  position: absolute;
  right: 7px;
  bottom: 11px;
  display: grid;
  width: 28px;
  height: 28px;
  padding: 0;
  place-items: center;
  border: 0;
  background: transparent;
  color: var(--text-primary);
  cursor: pointer;
  opacity: 0;
  transform: scale(0.86);
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
  z-index: 3;
}

.eye-button.is-visible {
  opacity: 1;
  transform: scale(1);
  pointer-events: auto;
}

.eye-button svg {
  width: 19px;
  height: 19px;
}

.auth-footer {
  display: grid;
  position: relative;
  grid-template-rows: 42px auto;
  min-height: 92px;
  justify-items: center;
  align-content: start;
  gap: 8px;
}

.submit-button {
  grid-area: 1 / 1;
  padding: 8px 12px;
  border: 0;
  background: transparent;
  cursor: pointer;
  opacity: 0;
  filter: blur(5px);
  transform: scale(0.96);
  pointer-events: none;
  transition: opacity 0.75s ease, filter 0.75s ease, transform 0.18s ease;
}

.auth-form.is-ready .submit-button {
  opacity: 1;
  filter: blur(0);
  transform: scale(1);
  pointer-events: auto;
}

.submit-button:active {
  transform: scale(0.94);
}

.auth-status {
  grid-area: 1 / 1;
  align-self: center;
  min-height: 1.2em;
  margin: 0;
  font-size: 1.45rem;
  font-weight: 900;
  letter-spacing: 0.04em;
  opacity: 0;
  filter: blur(5px);
  pointer-events: none;
  transition: opacity 0.3s ease, filter 0.3s ease;
}

.auth-status.is-success {
  color: var(--green);
  opacity: 1;
  filter: blur(0);
}

.password-help {
  grid-row: 2;
  grid-column: 1;
  margin: 0;
  color: var(--text-soft);
  font-size: 0.8rem;
  font-weight: 600;
  line-height: 1.5;
  text-align: center;
  opacity: 0;
  transform: translateY(3px);
  pointer-events: none;
  transition: opacity 0.4s ease, transform 0.4s ease;
}

.password-help.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.password-help a {
  color: inherit;
  text-underline-offset: 3px;
}

body.error-flash {
  animation: error-flash 2.2s cubic-bezier(.4, 0, .2, 1);
}

.welcome-page {
  display: block;
  padding: 0;
  text-align: center;
}

.welcome-content {
  position: absolute;
  top: 50%;
  left: 50%;
  width: min(calc(100% - 40px), 1600px);
  transform: translate(-50%, -50%);
}

.welcome-kicker {
  margin: 0 0 14px;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: clamp(1rem, 1.35vw, 1.45rem);
  font-weight: 500;
  letter-spacing: 0.12em;
}

.welcome-title {
  margin: 0 auto;
  max-width: 1100px;
  font-size: clamp(3rem, 9vw, 8.5rem);
  font-weight: 900;
  letter-spacing: -0.065em;
  line-height: 0.9;
}

.welcome-role {
  margin: 22px 0 0;
  color: var(--green);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: clamp(.85rem, 1.2vw, 1.15rem);
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.welcome-page.is-admin-welcome .welcome-title {
  white-space: nowrap;
  transform: none;
}

.dashboard-page {
  padding: max(50px, env(safe-area-inset-top)) max(5.2vw, env(safe-area-inset-right)) max(44px, env(safe-area-inset-bottom)) max(4.1vw, env(safe-area-inset-left));
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.account-nav {
  display: flex;
  align-items: center;
  gap: 11px;
  color: var(--text-primary);
  font-size: clamp(0.8rem, 1.05vw, 0.95rem);
  font-weight: 900;
  letter-spacing: 0.035em;
}

.nav-dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--text-soft);
}

.admin-mark,
.admin-dot {
  display: none;
}

.admin-mark.is-visible,
.admin-dot.is-visible {
  display: inline-flex;
}

.admin-mark {
  color: var(--green);
  padding: 3px 0;
  border: 0;
  background: transparent;
  font-weight: 900;
  letter-spacing: 0.035em;
  cursor: pointer;
}

.admin-mark.is-admin-active {
  color: var(--amber);
}

.logout-button {
  padding: 3px 0;
  border: 0;
  background: transparent;
  color: var(--scarlet);
  font-weight: 900;
  letter-spacing: 0.035em;
  cursor: pointer;
}

.nav-action {
  transform-origin: center;
  transition: color 0.35s ease, opacity 0.35s ease, transform 0.21s cubic-bezier(.22, 1, .36, 1), filter 0.35s ease;
}

.nav-action.is-pressed {
  transform: scale(1.15);
}

.workspace {
  position: relative;
  width: min(88%, 1355px);
  height: calc(100svh - 104px);
  margin: 0 auto;
}

.workspace-panel {
  position: absolute;
  inset: 0;
  visibility: hidden;
  opacity: 0;
  filter: blur(15px);
  pointer-events: none;
  transition: opacity 0.55s cubic-bezier(.4, 0, .2, 1), filter 0.55s cubic-bezier(.4, 0, .2, 1), visibility 0s linear 0.55s;
}

.workspace-panel.is-current {
  visibility: visible;
  opacity: 1;
  filter: blur(0);
  pointer-events: auto;
  transition-delay: 0s;
}

.workspace-panel.is-leaving {
  opacity: 0;
  filter: blur(15px);
}

.learning-shell,
.admin-shell {
  padding-top: clamp(88px, 10.5vh, 112px);
  padding-bottom: 90px;
  overflow-x: hidden;
  overflow-y: auto;
  -ms-overflow-style: none;
  scrollbar-width: none;
}

.learning-shell::-webkit-scrollbar,
.admin-shell::-webkit-scrollbar,
.lesson-reader::-webkit-scrollbar {
  display: none;
  width: 0;
  height: 0;
}

.display-title {
  margin: 0;
  font-size: clamp(5rem, 7.35vw, 7.7rem);
  font-weight: 900;
  letter-spacing: -0.075em;
  line-height: 0.82;
}

.display-initial {
  display: inline-block;
  font-size: 1.22em;
  margin-right: -0.02em;
}

.empty-course,
.course-browser {
  margin-top: clamp(48px, 6.2vh, 64px);
}

.course-instruction {
  margin: 0 0 9px;
  color: var(--text-secondary);
  font-size: clamp(0.72rem, 0.9vw, 0.85rem);
  font-weight: 800;
  letter-spacing: 0.025em;
  text-align: right;
}

.course-line {
  width: 100%;
  height: 1px;
  background: var(--line);
}

.signature {
  position: absolute;
  bottom: clamp(24px, 5.5vh, 58px);
  left: 0;
  margin: 0;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: clamp(0.72rem, 0.9vw, 0.84rem);
  font-weight: 500;
  letter-spacing: 0.08em;
}

.admin-tabs {
  position: relative;
  display: flex;
  width: 100%;
  gap: clamp(58px, 7.5vw, 122px);
  margin-top: clamp(60px, 7vh, 76px);
  border-bottom: 1px solid var(--line);
}

.admin-tab {
  padding: 0 26px 13px;
  border: 0;
  background: transparent;
  color: var(--text-soft);
  font-size: clamp(1rem, 1.35vw, 1.28rem);
  font-weight: 900;
  letter-spacing: 0.025em;
  cursor: pointer;
  transition: color 0.35s ease;
}

.admin-tab.is-current {
  color: var(--text-primary);
}

.tab-indicator {
  position: absolute;
  bottom: -1px;
  left: 0;
  height: 2px;
  background: var(--text-primary);
  transform: translateX(0);
  transition: width 0.55s cubic-bezier(.22, 1, .36, 1), transform 0.55s cubic-bezier(.22, 1, .36, 1);
}

.course-list {
  border-top: 1px solid var(--line);
  opacity: 1;
  filter: blur(0);
  transition: opacity 0.35s ease, filter 0.35s ease;
}

.course-guide {
  display: flex;
  min-height: 32px;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
}

.course-guide-back {
  flex: 0 0 auto;
  margin: 0 0 9px;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text-secondary);
  font-size: clamp(0.72rem, 0.9vw, 0.85rem);
  font-weight: 800;
  letter-spacing: .025em;
  opacity: 0;
  pointer-events: none;
  cursor: pointer;
  transition: opacity .35s ease, color .25s ease, transform .2s ease;
}

.course-guide-back.is-visible { opacity: 1; pointer-events: auto; }
.course-guide-back:active { transform: scale(.95); color: var(--amber); }

.course-list.is-changing {
  opacity: 0;
  filter: blur(7px);
}

.course-row {
  display: grid;
  width: 100%;
  min-height: 70px;
  grid-template-columns: 82px minmax(0, 1fr) 34px 42px;
  align-items: center;
  gap: 0;
  padding: 0 18px 0 6px;
  border: 0;
  border-bottom: 1px solid var(--line);
  background: transparent;
  color: var(--text-primary);
  text-align: left;
  cursor: pointer;
  transition: color 0.35s ease, background 0.35s ease, transform 0.25s cubic-bezier(.22, 1, .36, 1), opacity 0.35s ease;
  transform-origin: left center;
}

.course-row:active,
.course-row.is-opening {
  transform: scale(1.015);
  color: var(--amber);
}

.course-row.is-denied {
  transform: scale(.985);
  opacity: .55;
}

.course-number {
  color: var(--text-secondary);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .76rem;
  font-weight: 500;
}

.course-name {
  overflow: hidden;
  font-size: clamp(1rem, 1.55vw, 1.45rem);
  font-weight: 900;
  text-overflow: ellipsis;
}

.course-state {
  width: 19px;
  height: 19px;
  border: 2px solid var(--text-soft);
  border-radius: 50%;
}

.course-row.is-locked .course-state {
  opacity: .45;
}

.course-row.is-locked .course-name,
.course-row.is-locked .course-arrow {
  color: var(--text-soft);
}

.course-arrow {
  justify-self: end;
  color: var(--text-secondary);
  font-size: 1.6rem;
  font-weight: 400;
}

.admin-content {
  position: relative;
  min-height: 360px;
}

.admin-view {
  display: none;
  padding-top: clamp(28px, 3.5vh, 42px);
  opacity: 0;
  filter: blur(8px);
}

.admin-view.is-current {
  display: block;
  animation: admin-view-in .55s cubic-bezier(.4, 0, .2, 1) forwards;
}

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

.structure-heading h2,
.placeholder-view h2 {
  margin: 0;
  font-size: clamp(1.7rem, 2.6vw, 2.5rem);
  font-weight: 900;
  letter-spacing: .01em;
}

.account-name {
  padding: 3px 0;
  border: 0;
  background: transparent;
  color: inherit;
  font: inherit;
  letter-spacing: inherit;
  cursor: pointer;
}

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

.accounts-heading h2 { margin: 0; font-size: clamp(1.7rem, 2.6vw, 2.5rem); font-weight: 900; }
.accounts-heading .settings-card-label { margin: 0 0 12px; }

.accounts-list {
  display: grid;
  gap: 12px;
  margin-top: 34px;
}

.account-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 26px;
  align-items: center;
  padding: 22px 24px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.16);
  transition: border-color .25s ease, background .25s ease, transform .25s ease;
}

.account-card:hover { border-color: var(--text-secondary); background: color-mix(in srgb, var(--amber) 5%, transparent); transform: translateY(-2px); }
.account-card-type { color: var(--amber); font: 700 .68rem "DM Mono", monospace; letter-spacing: .08em; }
.account-card--admin .account-card-type { color: var(--green); }
.account-card--owner .account-card-type { color: var(--scarlet); }
.account-card-name { margin: 7px 0 4px; font-size: 1.15rem; font-weight: 900; }
.account-card-login { margin: 0; color: var(--text-secondary); font: 500 .72rem "DM Mono", monospace; }
.account-card-meta { display: flex; align-items: center; gap: 18px; color: var(--text-secondary); font: 500 .68rem "DM Mono", monospace; white-space: nowrap; }
.account-card-status { color: var(--green); }
.account-card-status.is-blocked { color: var(--scarlet); }
[hidden] { display: none !important; }
.account-card-action { padding: 6px 0; border: 0; background: transparent; color: var(--text-primary); font: 900 .7rem "Urbanist", sans-serif; cursor: pointer; }
.account-card-action:hover { color: var(--amber); }

.account-layer {
  position: fixed;
  z-index: 80;
  inset: 0;
  display: grid;
  padding: 24px;
  place-items: center;
  background: rgba(251,250,247,.38);
  opacity: 0;
  backdrop-filter: blur(0);
  pointer-events: none;
  transition: opacity .45s ease, backdrop-filter .45s ease;
}

.account-layer.is-visible { opacity: 1; backdrop-filter: blur(13px); pointer-events: auto; }
.account-modal { position: relative; width: min(100%, 720px); padding: 42px 44px 34px; border: 1px solid var(--line); background: var(--milk); box-shadow: 0 28px 80px rgba(41,41,41,.12); opacity: 0; filter: blur(10px); transform: translateY(16px) scale(.97); transition: opacity .45s ease, filter .45s ease, transform .45s cubic-bezier(.22,1,.36,1); }
.account-layer.is-visible .account-modal { opacity: 1; filter: blur(0); transform: translateY(0) scale(1); }
.account-modal h2 { margin: 0; font-size: clamp(2rem, 4vw, 3.2rem); font-weight: 900; }
.account-modal-close { position: absolute; top: 22px; right: 24px; border: 0; background: transparent; color: var(--text-secondary); font-size: 1.7rem; cursor: pointer; }
.account-form-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 18px 24px; margin-top: 32px; }
.student-account-fields { display: grid; gap: 18px; margin-top: 32px; }
.student-account-fields label { display: grid; gap: 8px; color: var(--text-soft); font: 500 .68rem "DM Mono", monospace; letter-spacing: .06em; }
.student-account-fields input { width: 100%; min-height: 38px; padding: 7px 2px; border: 0; border-bottom: 1px solid var(--line); outline: 0; background: transparent; color: var(--text-primary); font: 700 .95rem "Urbanist", sans-serif; }
.account-form-grid label { display: grid; gap: 8px; color: var(--text-soft); font: 500 .68rem "DM Mono", monospace; letter-spacing: .06em; }
.account-form-grid input,
.account-form-grid select { width: 100%; min-height: 38px; padding: 7px 2px; border: 0; border-bottom: 1px solid var(--line); outline: 0; background: transparent; color: var(--text-primary); font: 700 .95rem "Urbanist", sans-serif; }
.account-form-grid select { cursor: pointer; }
.account-access-toggle { align-content: start; }
.account-access-toggle .setting-switch { justify-self: start; margin-top: 1px; }
.account-access-toggle .setting-switch:disabled { opacity: .42; cursor: not-allowed; }
.account-password-field { position: relative; }
.account-password-field input { padding-right: 34px; }
.account-password-field button { position: absolute; right: 0; bottom: 7px; border: 0; background: transparent; color: var(--text-secondary); cursor: pointer; }
.account-form-note { min-height: 20px; margin: 20px 0 0; color: var(--text-secondary); font-size: .8rem; line-height: 1.4; }
.account-password-change { align-self: end; justify-self: start; padding: 8px 0; border: 0; background: transparent; color: var(--green); font: 900 .72rem "Urbanist", sans-serif; cursor: pointer; }
.account-form-grid > .account-password-change { grid-column: 1 / -1; justify-self: center; }
.student-account-fields .account-password-change { justify-self: center; }
.account-password-change:hover { color: var(--text-primary); }
.account-modal-actions { display: flex; justify-content: space-between; gap: 28px; margin-top: 24px; }
.account-modal-actions button { padding: 8px 0; border: 0; background: transparent; font-size: .82rem; font-weight: 900; cursor: pointer; }
.account-cancel { color: var(--scarlet); }
.account-submit { color: var(--green); }
.account-delete { color: var(--scarlet); }
.account-delete:hover { color: var(--text-primary); }
.accounts-heading .add-button { color: var(--green); }
.accounts-heading .add-button:active { transform: scale(.93); }

.password-layer {
  position: fixed;
  z-index: 150;
  inset: 0;
  display: grid;
  padding: 24px;
  place-items: center;
  background: rgba(251,250,247,.44);
  opacity: 0;
  backdrop-filter: blur(0);
  pointer-events: none;
  transition: opacity .45s ease, backdrop-filter .45s ease;
}
.password-layer.is-visible { opacity: 1; backdrop-filter: blur(14px); pointer-events: auto; }
.password-modal { position: relative; width: min(100%, 620px); padding: 42px 44px 34px; border: 1px solid var(--line); background: var(--milk); box-shadow: 0 28px 80px rgba(41,41,41,.16); opacity: 0; filter: blur(10px); transform: translateY(16px) scale(.97); transition: opacity .45s ease, filter .45s ease, transform .45s cubic-bezier(.22,1,.36,1); }
.password-layer.is-visible .password-modal { opacity: 1; filter: blur(0); transform: translateY(0) scale(1); }
.password-modal h2 { margin: 0; font-size: clamp(1.8rem, 4vw, 3rem); font-weight: 900; }
.password-form-grid { display: grid; gap: 18px; margin-top: 30px; }
.password-form-grid label { display: grid; gap: 8px; color: var(--text-soft); font: 500 .68rem "DM Mono", monospace; letter-spacing: .06em; }
.password-form-grid input { width: 100%; min-height: 38px; padding: 7px 2px; border: 0; border-bottom: 1px solid var(--line); outline: 0; background: transparent; color: var(--text-primary); font: 700 .95rem "Urbanist", sans-serif; }
.password-eye-field { position: relative; }
.password-eye-field input { padding-right: 34px; }
.password-eye-field button { position: absolute; right: 0; bottom: 7px; width: 24px; height: 24px; padding: 3px; border: 0; background: transparent; color: var(--text-secondary); cursor: pointer; }
.password-eye-field svg { display: block; width: 100%; height: 100%; }
.password-form-note { min-height: 20px; margin: 20px 0 0; color: var(--text-secondary); font-size: .8rem; line-height: 1.4; }

@media (max-width: 760px) {
  .accounts-heading { display: block; }
  .accounts-heading .add-button { margin-top: 22px; }
  .account-card { grid-template-columns: 1fr; gap: 16px; }
  .account-card-meta { flex-wrap: wrap; gap: 10px 16px; white-space: normal; }
  .account-form-grid { grid-template-columns: 1fr; }
  .account-modal { padding: 34px 24px 26px; }
  .password-modal { padding: 34px 24px 26px; }
}

.add-button,
.save-button,
.cancel-button {
  padding: 9px 8px;
  border: 0;
  background: transparent;
  font-weight: 900;
  letter-spacing: .035em;
  cursor: pointer;
  transition: color .35s ease, opacity .35s ease, transform .2s ease;
}

.add-button:active,
.save-button:active,
.cancel-button:active {
  transform: scale(.94);
}

.structure-table {
  margin-top: 34px;
}

.structure-table-head,
.structure-row {
  display: grid;
  grid-template-columns: minmax(380px, 1fr) 170px 120px 90px;
  align-items: center;
}

.structure-row.has-open-menu { z-index: 30; }

.structure-table-head {
  min-height: 42px;
  padding: 0 10px 0 70px;
  border-bottom: 1px solid var(--line);
  color: var(--text-primary);
  font-size: .72rem;
  font-weight: 900;
  letter-spacing: .045em;
}

.structure-row {
  position: relative;
  min-height: 64px;
  padding: 0 10px;
  border-bottom: 1px solid var(--line);
  transition: background .35s ease, opacity .35s ease;
}

.structure-row::before {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  width: 3px;
  background: var(--amber);
  content: "";
  opacity: 0;
  transition: opacity .25s ease;
}

.structure-row.is-selected {
  background: rgba(255, 174, 66, .065);
}

.structure-row.is-selected::before {
  opacity: 1;
}

.structure-row.is-drag-target {
  background: rgba(255, 174, 66, .13);
}

.structure-row.is-hidden-row .row-title {
  color: var(--text-soft);
}

.row-main {
  display: grid;
  min-width: 0;
  grid-template-columns: 28px 28px minmax(0, 1fr);
  align-items: center;
  padding: 0 12px 0 calc(var(--depth) * 42px);
  color: inherit;
  text-align: left;
}

.drag-handle,
.collapse-button,
.row-select {
  min-width: 0;
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  text-align: left;
  cursor: pointer;
}

.drag-handle {
  display: grid;
  width: 28px;
  height: 42px;
  place-items: center start;
  touch-action: none;
  cursor: grab;
}

.drag-handle:active { cursor: grabbing; }

.collapse-button,
.collapse-spacer {
  display: grid;
  width: 28px;
  height: 42px;
  place-items: center;
}

.collapse-button {
  color: var(--text-secondary);
  font-size: 1.25rem;
  transition: transform .35s ease, color .25s ease;
}

.collapse-button.is-collapsed { transform: rotate(-90deg); }

.row-select {
  display: flex;
  align-items: center;
  height: 52px;
}

.drag-mark {
  color: var(--text-secondary);
  font-size: 1.2rem;
}

.row-title {
  overflow: hidden;
  font-size: clamp(.8rem, 1.1vw, 1rem);
  font-weight: 900;
  letter-spacing: .02em;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.rename-input {
  width: min(100%, 520px);
  padding: 7px 8px;
  border: 0;
  border-bottom: 1px solid var(--text-primary);
  outline: 0;
  background: transparent;
  color: var(--text-primary);
  font-size: .95rem;
  font-weight: 900;
}

.row-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: .72rem;
  font-weight: 900;
  letter-spacing: .03em;
}

.row-status i {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: currentColor;
}

.row-status--green { color: var(--green); }
.row-status--amber { color: var(--amber); }

.visibility-button,
.more-button {
  display: grid;
  width: 42px;
  height: 42px;
  place-items: center;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
}

.eye-svg { width: 24px; height: 24px; }
.eye-svg .eye-slash { opacity: 0; }
.eye-svg.is-closed .eye-slash { opacity: 1; }

.row-menu-wrap {
  position: relative;
}

.more-button {
  font-size: 1rem;
  letter-spacing: .08em;
}

.action-menu {
  position: absolute;
  z-index: 15;
  top: 43px;
  right: 0;
  display: grid;
  width: 210px;
  padding: 8px 0;
  border: 1px solid var(--line);
  background: var(--milk);
  box-shadow: 0 18px 50px rgba(41, 41, 41, .12);
  animation: menu-in .25s ease both;
}

.action-menu.opens-up {
  top: auto;
  bottom: 43px;
  transform-origin: bottom right;
}

.action-menu button {
  padding: 11px 16px;
  border: 0;
  background: transparent;
  color: var(--text-primary);
  font-size: .75rem;
  font-weight: 900;
  text-align: center;
  cursor: pointer;
}

.action-menu button:disabled {
  color: var(--text-soft);
  cursor: default;
}

.action-menu small {
  margin-left: 5px;
  color: var(--text-soft);
  font-size: .58rem;
}

.action-menu .delete-action { color: var(--scarlet); }

.structure-empty {
  margin: 28px 0;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .78rem;
  line-height: 1.55;
}

.structure-actions {
  display: flex;
  justify-content: flex-end;
  gap: 30px;
  padding: 30px 0 12px;
}

.cancel-button,
.save-button {
  opacity: .28;
  pointer-events: none;
}

.cancel-button { color: var(--scarlet); }
.save-button { color: var(--green); }
.cancel-button.is-enabled,
.save-button.is-enabled { opacity: 1; pointer-events: auto; }

.notice {
  position: fixed;
  z-index: 50;
  left: 50%;
  bottom: max(26px, env(safe-area-inset-bottom));
  max-width: calc(100% - 40px);
  padding: 12px 18px;
  border: 1px solid var(--line);
  background: var(--milk);
  color: var(--text-primary);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .74rem;
  font-weight: 500;
  letter-spacing: .05em;
  text-align: center;
  opacity: 0;
  filter: blur(5px);
  pointer-events: none;
  transform: translate(-50%, 12px);
  transition: opacity .35s ease, filter .35s ease, transform .35s ease;
}

.notice.is-visible {
  opacity: 1;
  filter: blur(0);
  transform: translate(-50%, 0);
}

.notice--success { color: var(--green); }
.notice--error { border-color: var(--scarlet); background: var(--scarlet); color: var(--milk); }

.confirm-layer {
  position: fixed;
  z-index: 100;
  inset: 0;
  display: grid;
  padding: 24px;
  place-items: center;
  background: rgba(251, 250, 247, .4);
  opacity: 0;
  backdrop-filter: blur(0);
  pointer-events: none;
  transition: opacity .45s ease, backdrop-filter .45s ease;
}

.confirm-layer.is-visible {
  opacity: 1;
  backdrop-filter: blur(12px);
  pointer-events: auto;
}

.confirm-card {
  width: min(100%, 520px);
  padding: 42px 44px 34px;
  border: 1px solid var(--line);
  background: var(--milk);
  box-shadow: 0 28px 80px rgba(41, 41, 41, .12);
  opacity: 0;
  filter: blur(10px);
  transform: scale(.96);
  transition: opacity .45s ease, filter .45s ease, transform .45s cubic-bezier(.22, 1, .36, 1);
}

.confirm-layer.is-visible .confirm-card {
  opacity: 1;
  filter: blur(0);
  transform: scale(1);
}

.confirm-kicker {
  margin: 0 0 18px;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .72rem;
  letter-spacing: .12em;
}

.confirm-card h2 {
  margin: 0;
  font-size: clamp(1.7rem, 4vw, 2.5rem);
  font-weight: 900;
}

.confirm-copy {
  margin: 18px 0 34px;
  color: var(--text-secondary);
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.5;
}

.confirm-actions {
  display: flex;
  justify-content: space-between;
  gap: 60px;
}

.confirm-actions button {
  min-width: 88px;
  padding: 10px;
  border: 0;
  background: transparent;
  font-weight: 900;
  font-size: 1.05rem;
  cursor: pointer;
}

.confirm-no { color: var(--green); }
.confirm-yes { color: var(--scarlet); }

.course-browser,
.lesson-reader,
#learningTitle {
  transition: opacity .45s ease, filter .45s ease, transform .45s ease;
}

.course-browser.is-hidden,
#learningTitle.is-reader-hidden {
  opacity: 0;
  filter: blur(10px);
  pointer-events: none;
}

#learningTitle.is-title-changing {
  opacity: 0;
  filter: blur(10px);
  transform: translateY(8px);
}

.lesson-reader {
  position: absolute;
  inset: clamp(64px, 8vh, 92px) 0 0;
  visibility: hidden;
  overflow-x: hidden;
  overflow-y: auto;
  padding: 10px 2px 90px;
  opacity: 0;
  filter: blur(10px);
  transform: translateY(8px);
  pointer-events: none;
  -ms-overflow-style: none;
  scrollbar-width: none;
}

.lesson-reader.is-visible {
  visibility: visible;
  opacity: 1;
  filter: blur(0);
  transform: translateY(0);
  pointer-events: auto;
}

.reader-back,
.editor-back {
  padding: 5px 0;
  border: 0;
  background: transparent;
  color: var(--text-secondary);
  font-size: .83rem;
  font-weight: 900;
  letter-spacing: .03em;
  cursor: pointer;
}

.editor-back {
  min-height: 36px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255,255,255,.22);
  color: var(--text-primary);
  transition: color .25s ease, border-color .25s ease, background .25s ease, transform .2s ease;
}

.editor-back:hover,
.editor-back:focus-visible {
  border-color: var(--amber);
  background: color-mix(in srgb, var(--amber) 11%, transparent);
}

.editor-back:active { transform: scale(.96); }

.editor-path {
  margin: 46px 0 12px;
  color: var(--text-soft);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .8rem;
  line-height: 1.5;
}

.reader-title {
  max-width: 1050px;
  margin: 0 auto;
  text-align: center;
  font-size: clamp(2.8rem, 6vw, 6rem);
  font-weight: 900;
  letter-spacing: -.055em;
  line-height: .95;
}

.reader-content {
  width: min(100%, 900px);
  margin: 58px auto 0;
  text-align: center;
}

.reader-block {
  margin: 0 0 38px;
  color: var(--text-primary);
  font-size: 1.08rem;
  line-height: 1.7;
}

.reader-block h1,
.reader-block h2,
.reader-block h3 { margin: 0; line-height: 1.05; letter-spacing: -.025em; }
.reader-block h1 { font-size: clamp(2.4rem, 5vw, 4.7rem); }
.reader-block h2 { font-size: clamp(1.9rem, 4vw, 3.6rem); }
.reader-block h3 { font-size: clamp(1.5rem, 3vw, 2.7rem); }
.reader-block img,
.reader-block video { display: block; width: 100%; max-height: 72svh; object-fit: contain; }
.reader-block audio { width: 100%; }
.reader-block a { color: var(--text-primary); font-weight: 900; text-underline-offset: 5px; }
.lesson-reader.is-visible ~ .signature { opacity: 0; pointer-events: none; }
.reader-empty,
.missing-asset { color: var(--text-soft); font-family: "DM Mono", ui-monospace, monospace; font-size: .8rem; }

.editor-page {
  z-index: 7;
  padding: max(48px, env(safe-area-inset-top)) max(4.1vw, env(safe-area-inset-right)) max(36px, env(safe-area-inset-bottom)) max(4.1vw, env(safe-area-inset-left));
  overflow-y: auto;
}

.editor-admin-mark { color: var(--amber); }

.editor-workspace {
  width: min(100%, 1540px);
  margin: clamp(55px, 7vh, 80px) auto 0;
}

.editor-title {
  margin: 22px 0 0;
  font-size: clamp(4rem, 7.6vw, 8.2rem);
  font-weight: 900;
  letter-spacing: -.075em;
  line-height: .86;
}

.editor-path { margin-top: 25px; }

.editor-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 360px);
  gap: clamp(28px, 3vw, 48px);
  margin-top: 44px;
  align-items: start;
}

.editor-main {
  min-width: 0;
  overflow: visible;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: color-mix(in srgb, var(--milk) 72%, transparent);
  box-shadow: 0 18px 55px rgba(41, 41, 41, .06);
}

.lesson-name-field {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  align-items: center;
  min-height: 74px;
  gap: 24px;
  padding: 0 28px;
  border-bottom: 1px solid var(--line);
  font-size: .82rem;
  font-weight: 900;
}

.lesson-name-field input {
  width: 100%;
  padding: 10px 2px;
  border: 0;
  border-bottom: 1px solid var(--line);
  outline: 0;
  background: transparent;
  color: var(--text-primary);
  font-size: 1rem;
  font-weight: 800;
}

.lesson-block {
  position: relative;
  display: grid;
  grid-template-columns: 44px 190px minmax(0, 1fr) 44px;
  min-height: 104px;
  align-items: start;
  gap: 12px;
  padding: 28px;
  border-bottom: 1px solid var(--line);
  transition: background .25s ease, box-shadow .25s ease, transform .25s ease;
}

.lesson-block:hover { background: rgba(255, 255, 255, .26); box-shadow: inset 4px 0 0 color-mix(in srgb, var(--amber) 58%, transparent); }
.lesson-block:last-of-type { border-bottom: 0; }

.lesson-block.is-drag-target { background: rgba(255, 174, 66, .11); }
.lesson-block.is-dragging { opacity: .48; transform: scale(.985); }
.lesson-block.is-drag-target::after {
  position: absolute;
  z-index: 2;
  right: 0;
  top: 0;
  bottom: auto;
  left: 0;
  height: 3px;
  background: var(--amber);
  content: "";
  transform: translateY(-1px);
}
.lesson-block.is-drag-target.is-drop-after::after { top: auto; bottom: 0; transform: translateY(1px); }

.block-drag,
.block-more {
  width: 38px;
  height: 38px;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text-secondary);
  font-size: 1.15rem;
  cursor: grab;
  touch-action: none;
}

.block-more { cursor: pointer; letter-spacing: .08em; }

.block-label {
  padding-top: 9px;
  font-size: .82rem;
  letter-spacing: .02em;
}

.block-editor { min-width: 0; }

.lesson-block--heading .block-editor {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 28px;
}

.block-editor select,
.block-editor input {
  width: 100%;
  min-height: 38px;
  padding: 6px 2px;
  border: 0;
  border-bottom: 1px solid var(--line);
  outline: 0;
  background: transparent;
  color: var(--text-primary);
  font-size: .95rem;
  font-weight: 700;
}

.text-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 18px;
}

.text-toolbar button {
  display: inline-grid;
  min-width: 30px;
  min-height: 30px;
  place-items: center;
  padding: 4px 2px;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--text-primary);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .82rem;
  cursor: pointer;
  transition: color .2s ease, background .2s ease, transform .2s ease;
}

.text-toolbar button.is-active {
  background: #3f4143;
  color: var(--milk);
  transform: scale(1.04);
}

.rich-text {
  min-height: 82px;
  padding: 5px 2px 14px;
  border-bottom: 1px solid var(--line);
  outline: 0;
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .9rem;
  line-height: 1.6;
}

.rich-text:empty::before { color: var(--text-soft); content: attr(data-placeholder); }

.file-block-info {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  min-height: 38px;
  border-bottom: 1px solid var(--line);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .85rem;
}

.file-block-info button {
  border: 0;
  background: transparent;
  color: var(--amber);
  font-weight: 900;
  cursor: pointer;
}

.block-preview {
  display: block;
  width: min(100%, 620px);
  max-height: 340px;
  margin-top: 18px;
  object-fit: contain;
}

.block-menu {
  position: absolute;
  z-index: 4;
  top: 68px;
  right: 0;
  display: none;
  width: 160px;
  padding: 8px;
  border: 1px solid var(--line);
  background: var(--milk);
  box-shadow: 0 14px 40px rgba(41, 41, 41, .1);
}

.lesson-block.is-menu-open .block-menu { display: block; }
.block-menu button { width: 100%; padding: 9px; border: 0; background: transparent; color: var(--scarlet); font-weight: 900; text-align: center; cursor: pointer; }

.add-block-button {
  width: 100%;
  min-height: 70px;
  padding: 0 28px;
  border: 0;
  border-bottom: 1px solid var(--line);
  border-top: 1px dashed color-mix(in srgb, var(--line) 80%, transparent);
  background: transparent;
  color: var(--amber);
  font-size: 1rem;
  font-weight: 900;
  text-align: left;
  cursor: pointer;
}

.editor-sidebar {
  position: sticky;
  top: 28px;
  padding: 8px clamp(22px, 2.2vw, 30px) 24px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: color-mix(in srgb, var(--milk) 72%, transparent);
  box-shadow: 0 18px 55px rgba(41, 41, 41, .05);
}

.editor-setting {
  display: grid;
  min-height: 86px;
  align-content: center;
  gap: 11px;
  padding: 0 2px;
  border-bottom: 1px solid var(--line);
  font-family: "DM Mono", ui-monospace, monospace;
  font-size: .78rem;
  letter-spacing: .04em;
}

.editor-state { display: flex; align-items: center; gap: 10px; color: var(--green); font-family: "Urbanist", sans-serif; }
.editor-state i { width: 10px; height: 10px; border-radius: 50%; background: currentColor; }
.editor-state.is-changed { color: var(--amber); }

.setting-select {
  display: flex;
  justify-content: space-between;
  padding: 0 2px;
  border: 0;
  background: transparent;
  color: var(--text-primary);
  font-weight: 700;
  text-align: left;
  cursor: pointer;
}

.editor-toggle-setting {
  position: relative;
  grid-template-columns: 1fr 58px;
  align-items: center;
}

.editor-toggle-setting input { position: absolute; opacity: 0; pointer-events: none; }
.switch { position: relative; width: 50px; height: 28px; border-radius: 20px; background: var(--line); cursor: pointer; transition: background .25s ease; }
.switch::after { position: absolute; top: 4px; left: 4px; width: 20px; height: 20px; border-radius: 50%; background: var(--milk); content: ""; transition: transform .25s ease; }
.editor-toggle-setting input:checked + .switch { background: var(--green); }
.editor-toggle-setting input:checked + .switch::after { transform: translateX(22px); }

.editor-actions {
  display: flex;
  justify-content: space-between;
  gap: 28px;
  padding: 34px 2px 0;
}

.editor-actions button {
  padding: 8px;
  border: 0;
  background: transparent;
  font-size: 1rem;
  font-weight: 900;
  cursor: pointer;
}

.editor-delete { color: var(--scarlet); }
.editor-save { color: var(--green); opacity: .32; pointer-events: none; }
.editor-save.is-enabled { opacity: 1; pointer-events: auto; }

.block-picker-layer {
  position: fixed;
  z-index: 70;
  inset: 0;
  display: grid;
  padding: 24px;
  place-items: center;
  background: rgba(251, 250, 247, .4);
  opacity: 0;
  backdrop-filter: blur(0);
  pointer-events: none;
  transition: opacity .45s ease, backdrop-filter .45s ease;
}

.block-picker-layer.is-visible { opacity: 1; backdrop-filter: blur(12px); pointer-events: auto; }

.block-picker {
  width: min(100%, 680px);
  padding: 42px 44px 32px;
  border: 1px solid var(--line);
  background: var(--milk);
  box-shadow: 0 28px 80px rgba(41, 41, 41, .12);
  opacity: 0;
  filter: blur(10px);
  transform: translateY(18px) scale(.97);
  transition: opacity .45s ease, filter .45s ease, transform .45s cubic-bezier(.22, 1, .36, 1);
}

.block-picker-layer.is-visible .block-picker { opacity: 1; filter: blur(0); transform: translateY(0) scale(1); }
.block-picker h2 { margin: 0 0 28px; font-size: clamp(2rem, 4vw, 3.2rem); font-weight: 900; }
.block-options { display: grid; grid-template-columns: repeat(3, 1fr); }
.block-options button { min-height: 64px; padding: 10px; border: 0; border-right: 1px solid var(--line); background: transparent; color: var(--text-primary); font-size: .82rem; font-weight: 900; cursor: pointer; transition: color .25s ease, background .25s ease; }
.block-options button:nth-child(-n+3) { border-bottom: 1px solid var(--line); }
.block-options button:nth-child(3n) { border-right: 0; }
.block-options button:active { color: var(--amber); background: rgba(255, 174, 66, .08); }
.block-picker-cancel { display: block; margin: 28px 0 0 auto; padding: 8px; border: 0; background: transparent; color: var(--scarlet); font-weight: 900; cursor: pointer; }

body.is-reordering { user-select: none; cursor: grabbing; touch-action: none; }
.drag-ghost { position: fixed; z-index: 300; max-width: min(360px, 45vw); padding: 12px 16px; border: 1px solid var(--amber); background: var(--milk); box-shadow: 0 16px 40px rgba(41,41,41,.16); color: var(--text-primary); font: 800 .78rem "Urbanist", sans-serif; pointer-events: none; transform: rotate(1.5deg); }

@keyframes admin-view-in {
  to { opacity: 1; filter: blur(0); }
}

@keyframes menu-in {
  from { opacity: 0; filter: blur(5px); transform: translateY(-5px); }
}

.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;
}

@keyframes splash-name {
  0% { opacity: 0; filter: blur(18px); transform: translate(-50%, -50%) scale(.985); }
  28%, 72% { opacity: 1; filter: blur(0); transform: translate(-50%, -50%) scale(1); }
  100% { opacity: 0; filter: blur(9px); transform: translate(-50%, -50%) scale(1.01); }
}

@keyframes splash-rko {
  0% { opacity: 0; filter: blur(18px); transform: translate(-50%, -50%) scale(.985); }
  25%, 75% { opacity: 1; filter: blur(0); transform: translate(-50%, -50%) scale(1); }
  100% { opacity: 0; filter: blur(9px); transform: translate(-50%, -50%) scale(1.01); }
}

@keyframes splash-label {
  0% { opacity: 0; filter: blur(8px); }
  14%, 86% { opacity: 1; filter: blur(0); }
  100% { opacity: 0; filter: blur(4px); }
}

@keyframes error-flash {
  0%, 100% { background-color: var(--milk); }
  10%, 12% { background-color: var(--scarlet); }
}

@media (max-width: 720px) {
  .page-label,
  .splash-label {
    top: max(22px, env(safe-area-inset-top));
    left: max(20px, env(safe-area-inset-left));
  }

  .auth-page {
    place-items: start center;
    padding-top: max(80px, calc(env(safe-area-inset-top) + 58px));
  }

  .auth-form {
    min-height: 390px;
    padding: 30px 24px 24px;
  }

  .dashboard-page {
    padding: max(22px, env(safe-area-inset-top)) max(20px, env(safe-area-inset-right)) max(24px, env(safe-area-inset-bottom)) max(20px, env(safe-area-inset-left));
  }

  .topbar {
    align-items: flex-start;
  }

  .account-nav {
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 7px;
  }

  .workspace {
    width: 100%;
    height: calc(100svh - 66px);
  }

  .learning-shell,
  .admin-shell {
    padding-top: clamp(72px, 10vh, 104px);
  }

  .display-title {
    font-size: clamp(3.5rem, 18vw, 6rem);
  }

  .empty-course,
  .course-browser {
    margin-top: clamp(70px, 11vh, 112px);
  }

  .course-instruction {
    max-width: 290px;
    margin-left: auto;
    line-height: 1.35;
  }

  .course-guide { align-items: flex-end; gap: 12px; }
  .course-guide-back { font-size: .65rem; white-space: nowrap; }

  .signature {
    bottom: clamp(22px, 5vh, 48px);
  }

  .welcome-kicker {
    font-size: clamp(0.9rem, 4vw, 1.1rem);
  }

  .welcome-title {
    font-size: clamp(3rem, 18vw, 6rem);
  }

  .welcome-role { margin-top: 18px; font-size: .78rem; }

  .welcome-page.is-admin-welcome .welcome-title {
    font-size: clamp(2rem, 10.2vw, 4rem);
    transform: none;
  }

  .admin-shell .display-title {
    font-size: clamp(2.9rem, 12.5vw, 4.6rem);
  }

  .admin-tabs {
    gap: 0;
    margin-top: clamp(52px, 8vh, 78px);
  }

  .admin-tab {
    flex: 1;
    padding: 0 2px 12px;
    font-size: clamp(0.65rem, 2.75vw, 0.82rem);
  }

  .admin-shell {
    overflow-y: auto;
    padding-bottom: 40px;
  }

  .admin-content {
    min-width: 0;
  }

  .structure-heading {
    align-items: flex-end;
  }

  .structure-heading h2 {
    font-size: clamp(1.45rem, 7vw, 2rem);
  }

  .add-button {
    font-size: .72rem;
  }

  .structure-table {
    margin-top: 22px;
  }

  .structure-table-head {
    display: none;
  }

  .structure-row {
    grid-template-columns: minmax(0, 1fr) 42px 42px;
    min-height: 72px;
    padding: 0;
  }

  .row-main {
    grid-template-columns: 20px 18px minmax(0, 1fr);
    padding-left: calc(var(--depth) * 16px);
  }

  .drag-handle { width: 20px; }
  .collapse-button,
  .collapse-spacer { width: 18px; }
  .row-select { padding-left: 4px; }

  .drag-mark { font-size: .95rem; }
  .row-title { font-size: .76rem; white-space: normal; line-height: 1.25; }
  .row-status { position: absolute; left: calc(38px + var(--depth) * 16px); bottom: 7px; font-size: .58rem; }
  .row-status i { width: 6px; height: 6px; }
  .visibility-button { grid-column: 2; }
  .row-menu-wrap { grid-column: 3; }
  .action-menu { right: 0; width: 190px; }

  .course-row {
    min-height: 66px;
    grid-template-columns: 54px minmax(0, 1fr) 28px 30px;
    padding-right: 4px;
  }

  .course-name { font-size: .9rem; }
  .course-state { width: 16px; height: 16px; }
  .course-arrow { font-size: 1.25rem; }

  .confirm-card { padding: 32px 26px 26px; }

  .lesson-reader { inset: 52px 0 0; }
  .reader-title { font-size: clamp(2.5rem, 13vw, 4.3rem); }
  .reader-content { margin-top: 42px; }

  .editor-page {
    padding: max(22px, env(safe-area-inset-top)) max(20px, env(safe-area-inset-right)) max(28px, env(safe-area-inset-bottom)) max(20px, env(safe-area-inset-left));
  }

  .editor-workspace { margin-top: 56px; }
  .editor-title { font-size: clamp(3rem, 15vw, 5.3rem); }
  .editor-path { font-size: .67rem; }
  .editor-layout { grid-template-columns: 1fr; margin-top: 28px; }
  .lesson-name-field { grid-template-columns: 1fr; gap: 5px; padding: 16px 0; }
  .lesson-block { grid-template-columns: 30px minmax(0, 1fr) 38px; gap: 8px; padding-top: 22px; }
  .block-label { grid-column: 2; padding-top: 6px; }
  .block-editor { grid-column: 2 / 4; }
  .block-more { grid-column: 3; grid-row: 1; }
  .block-menu { top: 56px; }
  .lesson-block--heading .block-editor { grid-template-columns: 62px minmax(0, 1fr); gap: 12px; }
  .add-block-button { padding-left: 38px; }
  .editor-sidebar { position: static; padding: 8px 20px 22px; border: 1px solid var(--line); border-radius: 16px; }
  .editor-actions { padding: 34px 0; }
  .block-picker { padding: 32px 24px 24px; }
  .block-options { grid-template-columns: repeat(2, 1fr); }
  .block-options button:nth-child(3n) { border-right: 1px solid var(--line); }
  .block-options button:nth-child(2n) { border-right: 0; }
  .block-options button:nth-child(3) { border-bottom: 0; }
  .block-options button:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
}

@media (max-height: 650px) {
  .auth-form {
    min-height: min(370px, calc(100svh - 70px));
    gap: 14px;
    padding-top: 20px;
    padding-bottom: 18px;
  }

  .auth-fields {
    gap: 14px;
  }

  .learning-shell {
    padding-top: 9vh;
  }

  .empty-course,
  .course-browser {
    margin-top: 10vh;
  }

}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Course structure and settings refinements */
.structure-children {
  display: grid;
  grid-template-rows: 1fr;
  opacity: 1;
  transition: grid-template-rows .46s cubic-bezier(.22,1,.36,1), opacity .3s ease;
}

.structure-children-inner {
  min-height: 0;
  overflow: hidden;
}

.structure-children-inner:has(.has-open-menu) { overflow: visible; }

.structure-children.is-collapsed {
  grid-template-rows: 0fr;
  opacity: 0;
}

.collapse-button {
  transform: rotate(0deg);
  transition: transform .46s cubic-bezier(.22,1,.36,1), color .25s ease, background .25s ease;
}

.collapse-button svg {
  width: 20px;
  height: 20px;
  padding: 3px;
  border: 1px solid transparent;
  border-radius: 50%;
  transition: background .25s ease, border-color .25s ease;
}

.collapse-button:hover svg,
.collapse-button:focus-visible svg {
  border-color: var(--line);
  background: rgba(255,174,66,.11);
}

.collapse-button.is-collapsed { transform: rotate(-90deg); }

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

.settings-heading p {
  margin: 0;
  color: var(--text-soft);
  font: 500 .75rem "DM Mono", monospace;
  letter-spacing: .06em;
}

.settings-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 34px;
}

.settings-card {
  min-height: 250px;
  padding: 24px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.16);
}

.settings-card-label {
  margin: 0 0 30px;
  color: var(--text-soft);
  font: 500 .72rem "DM Mono", monospace;
  letter-spacing: .08em;
}

.settings-card h3 {
  margin: 0;
  font-size: 1.02rem;
  font-weight: 900;
}

.settings-card > p:not(.settings-card-label) {
  min-height: 62px;
  margin: 12px 0 22px;
  color: var(--text-secondary);
  font-size: .86rem;
  line-height: 1.45;
}

.setting-switch {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-height: 34px;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--text-secondary);
  font-size: .76rem;
  font-weight: 900;
  cursor: pointer;
}

.setting-switch-track {
  position: relative;
  display: inline-flex;
  width: 44px;
  height: 24px;
  align-items: center;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 999px;
  transition: background .3s ease, border-color .3s ease;
}

.setting-switch-track i {
  display: block;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--text-soft);
  transform: translateX(0);
  transition: transform .35s cubic-bezier(.22,1,.36,1), background .3s ease;
}

.setting-switch.is-on { color: var(--green); }
.setting-switch.is-on .setting-switch-track { border-color: var(--green); background: color-mix(in srgb, var(--green) 12%, transparent); }
.setting-switch.is-on .setting-switch-track i { background: var(--green); transform: translateX(18px); }

.text-action {
  display: block;
  margin-top: 24px;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--scarlet);
  font-size: .72rem;
  font-weight: 900;
  cursor: pointer;
}

.color-settings {
  display: flex;
  gap: 14px;
  margin-top: 18px;
}

.color-settings label {
  display: grid;
  gap: 7px;
  color: var(--text-soft);
  font: 500 .65rem "DM Mono", monospace;
}

.color-settings input {
  width: 54px;
  height: 34px;
  padding: 2px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
}

.editor-visibility-switch { justify-self: start; }

.reader-back,
.course-guide-back {
  min-height: 36px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255,255,255,.22);
  color: var(--text-primary);
  font-size: .78rem;
  letter-spacing: .025em;
  transition: color .25s ease, border-color .25s ease, background .25s ease, transform .2s ease;
}

.lesson-reader .reader-back {
  position: sticky;
  top: 0;
  z-index: 4;
  display: block;
  width: max-content;
  margin: 0;
  background: color-mix(in srgb, var(--milk) 88%, transparent);
  backdrop-filter: blur(8px);
}

.reader-back:hover,
.course-guide-back:hover,
.reader-back:focus-visible,
.course-guide-back:focus-visible {
  border-color: var(--amber);
  background: rgba(255,174,66,.1);
}

.reader-navigation {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 16px;
  width: min(100%, 900px);
  margin: 70px auto 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.reader-nav-button {
  padding: 8px 0;
  border: 0;
  background: transparent;
  color: var(--text-primary);
  font-size: .78rem;
  font-weight: 900;
  cursor: pointer;
  text-align: left;
}

.reader-nav-button:first-child { justify-self: start; text-align: left; }
.reader-nav-button:last-child { justify-self: end; text-align: right; }

.reader-nav-button:last-child { text-align: right; }
.reader-nav-button:disabled { color: var(--text-soft); opacity: .35; cursor: default; }
.reader-nav-button:not(:disabled):active { color: var(--amber); transform: scale(.96); }

.lesson-progress {
  display: flex;
  justify-content: center;
  gap: 8px;
  justify-self: center;
}

.progress-dot {
  display: block;
  width: 13px;
  height: 13px;
  border: 1px solid var(--text-primary);
  border-radius: 50%;
  background: transparent;
  transition: background .35s ease, transform .35s ease;
}

.progress-dot--visited { background: linear-gradient(90deg, var(--text-primary) 50%, transparent 50%); }
.progress-dot--completed { background: var(--text-primary); }
.progress-dot.is-current { transform: scale(1.22); box-shadow: 0 0 0 3px rgba(255,174,66,.2); }

.course-state {
  background: transparent;
  transition: background .35s ease, border-color .35s ease, transform .35s ease;
}

.course-row--visited .course-state {
  border-color: var(--text-primary);
  background: linear-gradient(90deg, var(--text-primary) 50%, transparent 50%);
}

.course-row--completed .course-state {
  border-color: var(--text-primary);
  background: var(--text-primary);
}

.course-row--visited .course-state,
.course-row--completed .course-state {
  transform: scale(1.08);
}

.signature span { font-weight: 900; }
.signature strong { font-weight: 900; }

.structure-row.is-selected { background: color-mix(in srgb, var(--amber) 8%, transparent); }
.structure-row.is-drag-target { background: color-mix(in srgb, var(--amber) 15%, transparent); }
.structure-row.is-drag-target { box-shadow: inset 0 3px 0 var(--amber); }
.structure-row.is-drag-target.is-drop-after { box-shadow: inset 0 -3px 0 var(--amber); }
.lesson-block.is-drag-target { background: color-mix(in srgb, var(--amber) 12%, transparent); }
.collapse-button:hover svg,
.collapse-button:focus-visible svg { background: color-mix(in srgb, var(--amber) 12%, transparent); }
.reader-back:hover,
.course-guide-back:hover,
.reader-back:focus-visible,
.course-guide-back:focus-visible { background: color-mix(in srgb, var(--amber) 11%, transparent); }
.progress-dot.is-current { box-shadow: 0 0 0 3px color-mix(in srgb, var(--amber) 25%, transparent); }

.reader-back {
  opacity: 0;
  filter: blur(8px);
  transform: translateY(6px);
  transition: opacity .55s ease, filter .55s ease, transform .55s cubic-bezier(.22,1,.36,1), color .25s ease, border-color .25s ease, background .25s ease;
}
.lesson-reader.is-visible .reader-back { opacity: 1; filter: blur(0); transform: translateY(0); }
.course-guide-back { filter: blur(7px); transform: translateY(5px); }
.course-guide-back.is-visible { filter: blur(0); transform: translateY(0); }

@media (max-width: 900px) {
  .settings-grid { grid-template-columns: 1fr; }
  .settings-card { min-height: 0; }
  .settings-card > p:not(.settings-card-label) { min-height: 0; }
  .settings-heading { display: block; }
  .settings-heading p { margin-top: 8px; }
}

@media (max-width: 720px) {
  .reader-navigation { gap: 8px; margin-top: 48px; }
  .reader-nav-button { font-size: .65rem; }
  .progress-dot { width: 11px; height: 11px; }
  .settings-card { padding: 20px; }
}