/* Padho — Core Views / 0 Landing / Frame 2 (735:130477), phone (729:46646). Landing sections only;
 * the masthead, footer, type and buttons are shared in site.css. */
.hero-background {
  position: absolute;
  inset: 0 0 auto;
  height: 798px;
  z-index: -1;
  background: linear-gradient(rgba(255,255,255,0),rgba(255,255,255,.3) 40%,#fff),linear-gradient(var(--landing-grid) 1px,transparent 1px),linear-gradient(90deg,var(--landing-grid) 1px,transparent 1px),var(--landing-cream);
  background-size: 100% 100%,24px 24px,24px 24px,100% 100%;
  pointer-events: none;
}
.hero {
  container-type: inline-size;
  text-align: center;
  padding-top: 96px;
  padding-bottom: 96px;
}
/* Each sentence keeps its own line. The first is 17.55em wide less 37 × 1.68px of tracking, so the
   type shrinks only where the hero is narrower than that (17.8 leaves ~1.5% slack for engine
   differences). Re-measure if the headline copy changes. */
.hero h1 {
  margin-inline: auto;
  font-size: 70px;
  font-size: min(70px, (100cqi + 62px) / 17.8);
  line-height: 84px;
  font-weight: 600;
  letter-spacing: -1.68px;
  color: #222;
}
.hero h1 .hero-line {
  display: block;
}
.hero h1 .hero-line:first-child {
  text-wrap: balance;
}
.hero h1 .accent {
  color: var(--color-brand-vermilion);
}
.hero-subtitle {
  max-width: 1000px;
  margin: 37px auto 56px;
  font-size: 32px;
  line-height: 37px;
  font-weight: 500;
  color: #222;
}
.hero-subtitle>span {
  display: block;
}
.hero-subtitle .accent {
  color: var(--color-brand-vermilion);
}
.hero-cta {
  min-width: 258px;
  font-size: 18px;
}
.live-class {
  margin-bottom: 160px;
}
.chapter-section {
  padding-block: 160px;
  background: var(--landing-cream);
  scroll-margin-top: 0;
}
.chapter-layout {
  display: grid;
  grid-template-columns: minmax(0,1fr) minmax(0,580px);
  gap: 104px;
  align-items: center;
}
.chapter-intro {
  min-width: 0;
  align-self: start;
}
.chapter-guide {
  position: relative;
  margin-top: 48px;
  min-height: 256px;
}
.picker-steps {
  position: relative;
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 20px;
  z-index: 1;
}
.picker-steps::before {
  content: "";
  position: absolute;
  top: 28px;
  left: 27px;
  width: 1px;
  height: 152px;
  background: var(--color-border-strong);
  z-index: -1;
}
.picker-steps button {
  display: flex;
  align-items: center;
  gap: 24px;
  max-width: 100%;
  border: 0;
  background: none;
  padding: 0;
  min-height: 56px;
  text-align: left;
  font-size: 18px;
  line-height: 28px;
  font-weight: 500;
}
.step-icon {
  display: grid;
  place-items: center;
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  border: 1px solid var(--color-border-strong);
  background: var(--color-surface);
  border-radius: 50%;
}
.picker-steps button:disabled .step-label {
  opacity: .4;
}
.picker-steps button[aria-current="step"] .step-icon {
  border-color: var(--color-primary);
}
.picker-steps button[data-completed] .step-icon {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
}
.student-portrait {
  position: absolute;
  right: -69px;
  bottom: -3px;
  width: 253px;
  height: 249px;
  overflow: hidden;
  pointer-events: none;
}
.student-portrait img {
  width: 100%;
  height: auto;
  transform: scaleX(-1);
}
.student-portrait::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom,transparent 75%,var(--landing-cream));
}
.picker-panel {
  min-width: 0;
  min-height: 556px;
  padding: 64px 40px;
  border-radius: var(--landing-card-radius);
  background: var(--color-surface);
  display: flex;
  flex-direction: column;
  gap: 24px;
  align-items: stretch;
}
.picker-header {
  position: relative;
  margin-bottom: 24px;
}
.picker-header h3 {
  font-size: 28px;
  line-height: 34px;
  font-weight: 400;
  letter-spacing: -1.68px;
  outline: none;
}
.picker-header>p {
  color: var(--color-text-muted);
  margin-top: 12px;
}
.back-button {
  min-height: 44px;
  gap: 8px;
  padding: 4px 8px;
  margin: 0 auto 16px 0;
  display: flex;
  width: max-content;
  font-weight: 400;
  font-size: 14px;
}
.back-button:hover {
  background: var(--color-surface-2);
}
.picker-options {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.choice-row,.chapter-row {
  position: relative;
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 56px;
  padding: 12px 16px;
  border: var(--stroke-default) solid var(--color-border-strong);
  border-radius: var(--radius-control);
  background: var(--color-surface);
  cursor: pointer;
  transition: background-color var(--duration-fast),border-color var(--duration-fast);
}
.choice-row:hover,.chapter-row:hover {
  background: var(--color-surface-2);
}
.choice-label,.chapter-row>span {
  flex: 1;
  min-width: 0;
}
.choice-row>input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
  inset: auto;
}
.choice-radio {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
  border: 1px solid var(--color-border-strong);
  border-radius: 50%;
  display: grid;
  place-items: center;
}
.choice-row:has(input:checked) {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
}
.choice-row:has(input:checked) .choice-radio {
  border-color: var(--color-primary);
}
.choice-row:has(input:checked) .choice-radio::after {
  content: "";
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
}
.choice-row:has(input:focus-visible) {
  outline: var(--stroke-focus) solid var(--color-ring);
  outline-offset: var(--focus-offset);
}
.choice-skeleton {
  height: 56px;
  border-radius: var(--radius-control);
  background: var(--color-surface-2);
  animation: landing-pulse var(--duration-skeleton-pulse) ease-in-out infinite;
}
.picker-message {
  color: var(--color-text-muted);
  font-size: var(--text-body-sm);
  line-height: var(--text-body-sm--line-height);
  text-align: center;
}
.picker-message:empty {
  display: none;
}
.picker-panel[aria-busy="true"] .picker-message {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
}
.picker-retry,.picker-fallback,.more-chapters {
  align-self: center;
}
.chapter-search {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 48px;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-control);
  padding: 8px 12px;
}
.chapter-search input {
  width: 100%;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--color-text);
}
.chapter-search:focus-within {
  outline: var(--stroke-focus) solid var(--color-ring);
  outline-offset: var(--focus-offset);
}
.chapter-search input::placeholder {
  color: var(--color-text-muted);
}
.chapter-row>img {
  flex-shrink: 0;
}
.community-section {
  background: var(--landing-cream);
  overflow: hidden;
}
.community-layout {
  position: relative;
  display: grid;
  grid-template-columns: 575px minmax(0,1fr);
  gap: 95px;
  padding-top: 160px;
  min-height: 768px;
}
.community-copy {
  min-width: 0;
  padding-bottom: 160px;
}
.community-copy>p {
  max-width: 498px;
  margin-top: 24px;
  color: var(--color-text-muted);
}
.community-copy>.button {
  width: 100%;
  max-width: 488px;
  margin-top: 48px;
}
.community-preview-frame {
  position: relative;
  margin-top: -20px;
  width: 980px;
  padding: 20px 0 0 20px;
  border: 1px solid var(--color-text-muted);
  border-bottom: 0;
  border-radius: 32px 0 0 0;
  overflow: hidden;
  height: 628px;
  align-self: start;
}
.community-preview {
  display: flex;
  width: 960px;
  min-height: 760px;
  background: var(--color-bg);
  font-size: 12px;
  line-height: 18px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-small) 0 0 0;
}
.preview-sidebar {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 15px;
  flex-shrink: 0;
  width: 48px;
  background: var(--color-surface);
  padding: 12px 9px;
  border-right: 1px solid var(--color-border);
}
.preview-sidebar>img {
  width: 20px;
  height: 20px;
  object-fit: contain;
}
.preview-sidebar>img:first-child {
  margin-bottom: 8px;
}
.preview-sidebar>hr {
  width: 100%;
  margin: 0;
  border: 0;
  border-top: 1px solid var(--color-divider);
}
.preview-community-main {
  min-width: 0;
  flex: 1;
}
.preview-topbar {
  height: 60px;
  padding: 20px 24px;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-divider);
}
.preview-discussions {
  padding: 24px;
}
.preview-discussion-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 36px;
}
.preview-discussion-heading h3 {
  font-size: 16px;
  line-height: 24px;
  font-weight: 500;
}
.preview-start-discussion {
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-control);
  padding: 8px 12px;
  background: #fff;
}
.preview-discussion-columns {
  display: flex;
  gap: 24px;
}
.preview-feed {
  width: 600px;
  flex-shrink: 0;
}
.preview-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 18px;
  color: var(--color-text-muted);
}
.preview-tabs {
  display: flex;
  align-items: center;
  padding: 3px;
  border-radius: 8px;
  background: var(--color-surface-2);
  gap: 4px;
}
.preview-tabs>span {
  padding: 5px 10px;
}
.preview-tabs>span:first-child {
  background: var(--color-surface);
  border-radius: 6px;
  box-shadow: var(--shadow-card);
  color: var(--color-text);
}
.preview-post {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 18px;
  margin-bottom: 12px;
  min-height: 122px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
}
.preview-stats {
  width: 60px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 10px;
  color: var(--color-text-muted);
  font-size: 10px;
  line-height: 14px;
}
.reply-count {
  padding: 2px 6px;
  border-radius: 6px;
  background: var(--color-success-soft);
  color: var(--color-success-text);
}
.preview-post-body {
  flex: 1;
  min-width: 0;
}
.preview-community-name {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--color-text-muted);
  font-size: 9px;
  line-height: 12px;
  letter-spacing: .54px;
  text-transform: uppercase;
  margin-bottom: 4px;
}
.preview-community-name>img {
  width: 15px;
  height: 15px;
}
.preview-post h4 {
  font-size: 13.5px;
  line-height: 18px;
  font-weight: 500;
}
.preview-post-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  border-top: 1px solid var(--color-divider);
  padding-top: 12px;
  margin-top: 15px;
  font-size: 10px;
  line-height: 14px;
}
.preview-post-footer>div {
  display: flex;
  gap: 6px;
}
.preview-post-footer>div>span {
  background: var(--color-surface-2);
  padding: 3px 6px;
  border-radius: 4px;
}
.preview-post-footer>p {
  white-space: nowrap;
}
.preview-chevron {
  width: 15px;
  height: 15px;
  align-self: center;
}
.preview-community-side {
  width: 240px;
  flex-shrink: 0;
  padding: 18px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  align-self: start;
}
.preview-community-side>h4 {
  font-size: 14px;
  margin-bottom: 16px;
}
.preview-community-side>h4:not(:first-child) {
  margin-top: 32px;
}
.preview-community-side>p {
  margin-top: 12px;
  color: var(--color-text-muted);
}
@keyframes landing-pulse {
  50% {
    opacity: .45;
  }
}
@media(min-width:1441px) {
  .hero-background {
    background-size: 100% 100%,24px 24px,24px 24px,100% 100%;
  }
}
@media(min-width:1024px) and (max-width:1279px) {
  .hero h1 {
    font-size: 60px;
    font-size: min(60px, (100cqi + 62px) / 17.8);
    line-height: 70px;
  }
  .hero-subtitle {
    font-size: 28px;
    line-height: 34px;
  }
  .chapter-layout {
    gap: 48px;
    grid-template-columns: minmax(0,1fr) minmax(0,1fr);
  }
  .chapter-guide {
    margin-top: 40px;
  }
  .student-portrait {
    right: -20px;
    width: 180px;
    height: 180px;
    bottom: -24px;
  }
  .picker-steps button {
    gap: 16px;
  }
  .community-layout {
    grid-template-columns: 48% minmax(0,1fr);
    gap: 48px;
  }
}
@media(max-width:1023px) {
  .hero {
    padding-top: 64px;
    padding-bottom: 72px;
  }
  .hero h1 {
    font-size: 52px;
    line-height: 60px;
    max-width: 720px;
  }
  .hero-subtitle {
    font-size: 24px;
    line-height: 30px;
    margin: 28px auto 40px;
    max-width: 650px;
  }
  .live-class {
    margin-bottom: 96px;
  }
  .chapter-section {
    padding-block: 80px;
  }
  .chapter-layout {
    grid-template-columns: 1fr;
    gap: 48px;
    max-width: 640px;
  }
  .chapter-intro h2 {
    max-width: 600px;
  }
  .chapter-guide {
    max-width: 500px;
  }
  .student-portrait {
    right: 0;
    bottom: 0;
  }
  .picker-panel {
    width: 100%;
    min-height: 0;
  }
  .community-layout {
    grid-template-columns: minmax(0,1fr);
    gap: 48px;
    padding-top: 80px;
    max-width: 640px;
    min-height: 0;
  }
  .community-copy {
    padding-bottom: 0;
  }
  .community-copy>.button {
    max-width: 100%;
  }
  .community-preview-frame {
    margin-top: 0;
    height: 440px;
  }
}
@media(max-width:639px) {
  /* Core Views phone keeps the desktop heading tracking; site.css loosens it for the other pages. */
  :root {
    --landing-heading-tracking: -1.68px;
  }
  .hero-background {
    height: 742px;
  }
  .hero {
    width: calc(100% - 40px);
    padding-top: 64px;
    padding-bottom: 56px;
  }
  /* Core Views lets the headline run 9px past the hero gutter, which keeps it to three lines. */
  .hero h1 {
    font-size: 36px;
    line-height: 42px;
    letter-spacing: -1.68px;
    max-width: 390px;
    margin-inline: -9px;
  }
  .hero-subtitle {
    font-size: 18px;
    line-height: 26px;
    max-width: 310px;
    margin: 20px auto 40px;
  }
  .hero .hero-cta {
    width: 100%;
    min-height: 48px;
    font-size: 16px;
  }
  .live-class {
    margin-bottom: 72px;
  }
  .chapter-section {
    padding-block: 72px 80px;
  }
  .chapter-layout {
    gap: 32px;
  }
  .chapter-guide {
    margin-top: 26px;
    min-height: 170px;
  }
  .picker-steps {
    gap: 16px;
  }
  .picker-steps::before {
    display: none;
  }
  .picker-steps button {
    gap: 16px;
    min-height: 46px;
  }
  .step-icon {
    width: 46px;
    height: 46px;
  }
  .student-portrait {
    width: 149px;
    height: 147px;
    right: 0;
    bottom: 0;
  }
  .picker-panel {
    padding: 24px 20px;
    gap: 24px;
  }
  .picker-header {
    margin-bottom: 0;
  }
  .picker-header h3 {
    font-size: 24px;
    line-height: 30px;
    letter-spacing: normal;
  }
  .picker-header>p {
    margin-top: 8px;
    font-size: 14px;
    line-height: 20px;
  }
  .back-button {
    margin-bottom: 12px;
  }
  .community-layout {
    padding-top: 72px;
    gap: 49px;
  }
  .community-copy>p {
    font-size: 16px;
    line-height: 24px;
    margin-top: 51px;
  }
  .community-copy>.button {
    min-height: 48px;
    margin-top: 8px;
  }
  /* The desktop frame at the preview's .518 scale. */
  .community-preview-frame {
    width: 508px;
    height: 326px;
    padding: 10px 0 0 10px;
    border-width: .518px .518px 0;
    border-radius: 16.576px 0 0 0;
  }
  .community-preview {
    transform: scale(.518);
    transform-origin: top left;
  }
}
@media(max-width:359px) {
  .hero h1 {
    font-size: 32px;
    line-height: 38px;
  }
  .student-portrait {
    width: 120px;
    height: 130px;
    right: -16px;
    bottom: 0;
  }
  .picker-steps button {
    gap: 12px;
    font-size: 16px;
  }
}

/* Badge exported from Core Views › 0 Landing (697:966357), 16px above the headline as in Figma. */
.hero-badge {
  width: auto;
  height: 64px;
  margin: 0 auto 16px;
}
/* Google's badge is used as supplied (no recolouring); the 24px gaps exceed its required clear space of ¼ its height. */
.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
}
.hero-divider {
  width: var(--stroke-default);
  height: 44px;
  background: var(--color-border-strong);
}
.play-badge {
  display: flex;
  border-radius: 10px;
  transition: transform var(--duration-standard) var(--ease-move);
}
.play-badge>img {
  width: auto;
  height: 64px;
}
@media(hover:hover) {
  .play-badge:hover {
    transform: translateY(-2px);
  }
}
/* Android visitors go to the app: the badge is the hero's only action (site.js re-points the links). */
[data-platform="android"] .hero-cta,[data-platform="android"] .hero-divider {
  display: none;
}

/* A real recorded class (waits cut, cropped to the app window); class-video.js plays it while on screen. */
.class-video {
  position: relative;
  overflow: hidden;
  aspect-ratio: 2560/1412;
  border: var(--stroke-default) solid var(--color-border-strong);
  border-radius: var(--radius-small);
  background: var(--color-bg);
}
.class-video>video {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  cursor: pointer;
}
/* Bottom-left sits on the empty left end of the class's control bar, so it never covers the board. */
.video-sound {
  position: absolute;
  bottom: 16px;
  left: 16px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  width: 160px;
  min-height: 40px;
  padding: 10px 8px;
  border: 0;
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  font-size: var(--text-body-sm);
  line-height: var(--text-body-sm--line-height);
}
.video-sound:hover {
  background: var(--color-surface-2);
}
.video-sound>.sound-on,.video-sound[aria-pressed="true"]>.sound-off {
  display: none;
}
.video-sound[aria-pressed="true"]>.sound-on {
  display: block;
}
.video-play {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  width: 80px;
  height: 80px;
  margin: auto;
  border: 0;
  border-radius: 50%;
  background: var(--color-surface);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration-standard) var(--ease-move);
}
.class-video.is-paused>.video-play {
  opacity: 1;
  pointer-events: auto;
}

@property --mastery {
  syntax: '<percentage>';
  inherits: true;
  initial-value: 0%;
}
@property --score {
  syntax: '<integer>';
  inherits: true;
  initial-value: 0;
}
@property --bar {
  syntax: '<color>';
  inherits: true;
  initial-value: transparent;
}
.features-section {
  padding-block: 160px;
  background: var(--color-surface);
}
.features-heading {
  max-width: 720px;
  margin-bottom: 64px;
}
.feature-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3,minmax(0,1fr));
  gap: 24px;
}
.feature-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 7px 7px 29px;
  border: var(--stroke-default) solid var(--color-border);
  border-radius: var(--landing-card-radius);
  background: var(--color-surface);
  transition: transform var(--duration-slow) var(--ease-move),box-shadow var(--duration-slow) var(--ease-move);
}
.feature-card>h3 {
  margin: 24px 16px 0;
  font-size: 22px;
  line-height: 28px;
  font-weight: 500;
}
.feature-card>p {
  margin: 8px 16px 0;
  color: var(--color-text-muted);
}
/* Inner radius = card radius − card padding, so the corners stay concentric. */
.feature-visual {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 16px;
  height: 232px;
  padding: 16px;
  overflow: hidden;
  border-radius: calc(var(--landing-card-radius) - 8px);
  background: linear-gradient(0deg,transparent 23px,var(--color-surface-2) 24px) 0 0/24px 24px,linear-gradient(90deg,transparent 23px,var(--color-surface-2) 24px) 0 0/24px 24px,var(--color-bg);
  font-size: 14px;
  line-height: 20px;
}
.visual-kicker {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 11px;
  line-height: 16px;
  font-weight: 500;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}
.mark {
  display: inline-flex;
  align-items: center;
  padding: 2px 10px;
  border-radius: var(--radius-pill);
  font-size: 12px;
  line-height: 18px;
  font-weight: 500;
  white-space: nowrap;
}
.mark.shaky {
  background: var(--color-warning-soft);
  color: var(--color-warning-text);
}

/* The live class still (Core Views › 04 Learn, 364:17689) has --color-bg edges, so `contain` letterboxes
 * seamlessly and Feny is never cropped on narrow cards. */
.app-shot {
  justify-content: center;
  padding: 0;
  border: var(--stroke-default) solid var(--color-border);
  background: var(--color-bg);
}
.app-shot>img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  transition: transform var(--duration-screen) var(--ease-move);
}

/* Ask Feny's start screen, rebuilt live; ask-demo.js types a question into it. */
.ask-mock {
  container-type: inline-size;
  gap: 10px;
  padding: 16px 14px 14px;
  background: var(--color-bg);
}
.ask-title {
  text-align: center;
  font-size: 13px;
  line-height: 18px;
}
.ask-tiles {
  display: grid;
  grid-template-columns: repeat(2,minmax(0,1fr));
  gap: 6px;
  transition: opacity var(--duration-slow) var(--ease-move);
}
.ask-tile {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 44px;
  padding: 6px 10px;
  border: var(--stroke-default) solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  font-size: 12px;
  line-height: 15px;
  font-weight: 500;
}
.ask-tile>img {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}
.ask-composer {
  display: flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  margin-top: auto;
  padding: 0 5px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  transition: border-color var(--duration-standard) var(--ease-move);
}
.ask-avatar {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}
/* Right-aligned overflow keeps the newest characters in view, as a real input scrolls. */
.ask-field {
  flex: 1;
  min-width: 0;
  display: flex;
  justify-content: flex-end;
  overflow: hidden;
  font-size: 13px;
  line-height: 20px;
  white-space: nowrap;
}
.ask-typed {
  flex: 0 0 auto;
  min-width: 100%;
}
.ask-field.is-overflowing {
  -webkit-mask-image: linear-gradient(90deg,transparent,#000 16px);
  mask-image: linear-gradient(90deg,transparent,#000 16px);
}
.ask-placeholder {
  flex: 1 1 0;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--color-text-muted);
}
.ask-typed::after {
  content: "";
  display: inline-block;
  width: 1.5px;
  height: 15px;
  margin-left: 1px;
  vertical-align: -2px;
  background: var(--color-primary);
  animation: caret-blink calc(var(--duration-caret-blink)*2) steps(1,end) infinite;
}
.card-ask:not(.is-asking) .ask-typed,.card-ask.is-asking .ask-placeholder {
  display: none;
}
.ask-action {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}
.ask-send {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--color-surface-2);
  transition: background-color var(--duration-standard) var(--ease-move);
}
.ask-send>img {
  width: 16px;
  height: 16px;
  opacity: .4;
}
.card-ask.is-asking .ask-composer {
  border-color: var(--color-primary);
}
.card-ask.is-asking .ask-tiles {
  opacity: .45;
}
.card-ask.is-ready .ask-send {
  background: var(--color-primary);
  animation: send-pop 360ms var(--ease-enter);
}
.card-ask.is-ready .ask-send>img {
  opacity: 1;
  filter: brightness(0) invert(1);
}
.card-ask.is-ready .ask-avatar {
  animation: feny-wiggle 600ms var(--ease-move) 120ms;
}
@container (max-width:300px) {
  .ask-title {
    font-size: 12px;
  }
  .ask-tile {
    gap: 6px;
    padding: 6px 8px;
    font-size: 11px;
    line-height: 14px;
  }
  .ask-tile>img {
    width: 16px;
    height: 16px;
  }
  .ask-composer>.ask-action:first-of-type {
    display: none;
  }
}
@keyframes caret-blink {
  50% {
    opacity: 0;
  }
}
@keyframes send-pop {
  50% {
    transform: scale(1.18);
  }
}
@keyframes feny-wiggle {
  30% {
    transform: rotate(-10deg);
  }
  65% {
    transform: rotate(6deg);
  }
}

.gap-graph {
  display: grid;
  grid-template-rows: auto 36px auto auto;
  justify-items: center;
}
.node {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border: var(--stroke-default) solid var(--color-border-strong);
  border-radius: var(--radius-pill);
  background: var(--color-surface);
  white-space: nowrap;
  font-weight: 500;
  transition: box-shadow var(--duration-slow) var(--ease-move);
}
.node.known>svg {
  fill: none;
  stroke: var(--color-success);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.node.missing {
  border: 2px dashed var(--color-accent);
  padding: 6px 13px;
}
.gap-links {
  display: block;
  width: 100%;
  height: 36px;
  overflow: visible;
}
.gap-links>path {
  fill: none;
  stroke: var(--color-border-strong);
  stroke-width: 1.5;
  vector-effect: non-scaling-stroke;
}
.gap-links>path.missing {
  stroke: var(--color-accent);
  stroke-dasharray: 5 4;
}
.gap-prereqs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  justify-items: center;
  width: 100%;
}
.gap-prereqs+.gap-prereqs {
  margin-top: 8px;
}
.gap-prereqs .mark {
  transition: transform var(--duration-slow) var(--ease-move);
}

.study-card,.mastery {
  border: var(--stroke-default) solid var(--color-border);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
}

.study-stack {
  position: relative;
  flex: 1;
  container-type: inline-size;
}
.study-card {
  position: absolute;
  inset: 0;
  margin: auto;
  width: clamp(92px,36cqw,128px);
  height: 104px;
  padding: 10px 12px;
  font-size: clamp(12px,4.6cqw,14px);
  line-height: 1.4;
  border-radius: var(--radius-control);
  transition: transform var(--duration-screen) var(--ease-move);
}
.study-card>small {
  display: block;
  margin-bottom: 6px;
  font-size: clamp(9px,3.4cqw,10px);
  line-height: 14px;
  font-weight: 500;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}
.study-card>p {
  font-weight: 500;
}
/* A hand of cards pivoting at the bottom: the side cards' tops clear the flashcard, so their text hugs the visible edge. */
.study-card.formula,.study-card.practice {
  transform-origin: 50% 100%;
  white-space: nowrap;
}
.study-card.formula {
  transform: translateX(-27cqw) rotate(-12deg);
}
.study-card.practice {
  text-align: right;
  transform: translateX(27cqw) rotate(12deg);
}
.study-card.flash {
  z-index: 1;
  width: clamp(84px,30cqw,112px);
  background: var(--color-hero);
  color: var(--color-hero-text);
  border-color: transparent;
}
.study-card.flash>small {
  color: inherit;
  opacity: .7;
}

.lab-tray {
  display: grid;
  grid-template-columns: repeat(4,minmax(0,1fr));
  gap: 8px;
}
.apparatus {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  height: 72px;
  padding-top: 8px;
  border: var(--stroke-default) solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-surface);
  box-shadow: var(--shadow-card);
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
}
.apparatus>img {
  width: 36px;
  height: 36px;
}
.apparatus.empty {
  border: var(--stroke-default) dashed var(--color-border-strong);
  background: transparent;
  box-shadow: none;
}
.lab-bench {
  flex: 1;
  display: flex;
  align-items: flex-end;
  padding: 10px 12px;
  border: var(--stroke-default) dashed var(--color-border-strong);
  border-radius: var(--radius-control);
  color: var(--color-text-muted);
  font-size: 12px;
  line-height: 16px;
}
/* The pulley mid-drag from its empty slot onto the bench. */
.apparatus.lifted {
  position: absolute;
  left: 48%;
  bottom: 30px;
  width: 64px;
  transform: rotate(-6deg);
  box-shadow: var(--shadow-overlay);
  transition: transform var(--duration-screen) var(--ease-move),box-shadow var(--duration-screen) var(--ease-move);
}

.mastery {
  list-style: none;
  margin: 0;
  padding: 14px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  border-radius: var(--radius-control);
}
.mastery>li {
  display: grid;
  grid-template-columns: minmax(0,1fr) auto;
  column-gap: 12px;
  row-gap: 6px;
  transition: --mastery 700ms var(--ease-move),--score 700ms var(--ease-move),--bar 700ms var(--ease-move);
}
.mastery>li>span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.mastery>li>b {
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  counter-reset: score var(--score);
}
.mastery>li>b::before {
  content: counter(score) "%";
}
.mastery>li::after {
  content: "";
  grid-column: 1/-1;
  height: 6px;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg,var(--bar) var(--mastery),var(--color-surface-2) var(--mastery));
}
.mastery>.strong {
  --mastery: 86%;
  --score: 86;
  --bar: var(--color-mastery-strong);
}
.mastery>.developing {
  --mastery: 62%;
  --score: 62;
  --bar: var(--color-mastery-developing);
}
.mastery>.weak {
  --mastery: 34%;
  --score: 34;
  --bar: var(--color-mastery-weak);
}

/* Hover brings each picture to life: the card lifts and its feature plays out. */
@media(hover:hover) and (pointer:fine) {
  .feature-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-overlay);
  }
  .feature-card:hover .app-shot>img {
    transform: scale(1.05);
  }
  .card-gap:hover .gap-links>path.missing {
    animation: dash-march 700ms linear infinite;
  }
  .card-gap:hover .node.missing {
    box-shadow: 0 0 0 6px color-mix(in srgb,var(--color-accent) 18%,transparent);
  }
  .card-gap:hover .gap-prereqs .mark {
    transform: translateY(-2px);
  }
  .card-sets:hover .study-card.formula {
    transform: translateX(-31cqw) rotate(-18deg);
  }
  .card-sets:hover .study-card.practice {
    transform: translateX(31cqw) rotate(18deg);
  }
  .card-sets:hover .study-card.flash {
    transform: translateY(-8px);
  }
  .card-lab:hover .apparatus.lifted {
    transform: translate(-38%,18px);
    box-shadow: var(--shadow-card);
  }
  .card-progress:hover .mastery>.weak {
    --mastery: 58%;
    --score: 58;
    --bar: var(--color-mastery-developing);
  }
}
@keyframes dash-march {
  to {
    stroke-dashoffset: -18;
  }
}

/* Scroll-in life (feature-motion.js): cards rise in staggered across the row, then each plays its own move once.
 * Every animation fills backwards only, so once it ends a card is back on its resting styles and hover still works. */
.feature-grid[data-motion] .feature-card:not(.is-in-view) {
  opacity: 0;
}
.feature-grid[data-motion] .feature-card.is-in-view {
  animation: card-rise 640ms var(--ease-enter) var(--reveal-delay,0ms) backwards;
}
@keyframes card-rise {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
}
.card-lesson.is-in-view .app-shot>img {
  animation: shot-settle 1600ms var(--ease-move) var(--reveal-delay,0ms) backwards;
}
@keyframes shot-settle {
  from {
    transform: scale(1.12);
  }
}
.card-gap.is-live .gap-links>path.missing {
  animation: dash-march 700ms linear 3;
}
.card-gap.is-live .node.missing {
  animation: gap-glow 1100ms var(--ease-move) 2;
}
@keyframes gap-glow {
  50% {
    box-shadow: 0 0 0 7px color-mix(in srgb,var(--color-accent) 24%,transparent);
  }
}
.card-gap.is-in-view .gap-prereqs .mark {
  animation: mark-pop 520ms var(--ease-enter) calc(var(--reveal-delay,0ms) + 1500ms) backwards;
}
@keyframes mark-pop {
  from {
    opacity: 0;
    transform: translateY(8px) scale(.9);
  }
}
/* Study sets are dealt: the stack sits square, then the formula sheet and practice set fan out to either side. */
.card-sets.is-in-view .study-card.flash {
  animation: flash-lift 560ms var(--ease-enter) calc(var(--reveal-delay,0ms) + 260ms) backwards;
}
.card-sets.is-in-view .study-card.formula {
  animation: deal 720ms var(--ease-enter) calc(var(--reveal-delay,0ms) + 420ms) backwards;
}
.card-sets.is-in-view .study-card.practice {
  animation: deal 720ms var(--ease-enter) calc(var(--reveal-delay,0ms) + 560ms) backwards;
}
@keyframes flash-lift {
  from {
    transform: translateY(14px);
  }
}
@keyframes deal {
  from {
    transform: none;
  }
}
/* The pulley is picked up from the tray and carried onto the bench. */
.card-lab.is-in-view .apparatus.lifted {
  animation: pick-place 1000ms var(--ease-move) calc(var(--reveal-delay,0ms) + 420ms) backwards;
}
@keyframes pick-place {
  from {
    opacity: 0;
    transform: translate(-110%,-92px) rotate(0deg);
  }
  35% {
    opacity: 1;
  }
  75% {
    transform: translate(-3%,-8px) rotate(-10deg);
  }
}
/* Mastery bars fill from empty and the percentages count up, one row after another. */
.feature-grid[data-motion] .card-progress:not(.is-live) .mastery>li {
  --mastery: 0%;
  --score: 0;
}
.card-progress:not(:hover) .mastery>li:nth-child(2) {
  transition-delay: 140ms;
}
.card-progress:not(:hover) .mastery>li:nth-child(3) {
  transition-delay: 280ms;
}

@media(min-width:1024px) and (max-width:1279px) {
  .feature-grid {
    gap: 16px;
  }
}
@media(max-width:1023px) {
  .features-section {
    padding-block: 96px;
  }
  .features-heading {
    margin-bottom: 48px;
  }
  .feature-grid {
    grid-template-columns: repeat(2,minmax(0,1fr));
    gap: 16px;
  }
}
@media(max-width:639px) {
  .hero-badge {
    height: 48px;
  }
  .video-sound {
    bottom: 6px;
    left: 8px;
    justify-content: center;
    width: 36px;
    min-height: 36px;
    padding: 0;
  }
  .video-sound>span {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
  }
  .video-play {
    width: 56px;
    height: 56px;
  }
  .hero-actions {
    flex-direction: column;
    gap: 16px;
  }
  .hero-divider {
    display: none;
  }
  .play-badge>img {
    height: 52px;
  }
  [data-platform="android"] .play-badge>img {
    height: 60px;
  }
  .features-section {
    padding-block: 72px;
  }
  .features-heading {
    margin-bottom: 32px;
  }
  .feature-grid {
    grid-template-columns: minmax(0,1fr);
  }
  .feature-card>h3 {
    margin-top: 20px;
    font-size: 20px;
    line-height: 26px;
  }
}