:root {
  --page: #f7f8fc;
  --surface: #fff;
  --ink: #22243b;
  --muted: #81859a;
  --line: #e9eaf2;
  --accent: #6556e8;
  --accent-dark: #5141d1;
  --accent-tint: #eeecff;
  --font:
    Inter, "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, Arial,
    sans-serif;
  color-scheme: light;
  font-family: var(--font);
  font-size: 16px;
  color: var(--ink);
  background: var(--page);
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
}
button,
a {
  -webkit-tap-highlight-color: transparent;
}
button {
  font: inherit;
  color: inherit;
  cursor: pointer;
}
button:disabled {
  cursor: default;
  opacity: 0.34;
}
button,
a {
  touch-action: manipulation;
}
button:focus-visible,
a:focus-visible {
  outline: 3px solid #a39af7;
  outline-offset: 4px;
}
button {
  border: 0;
  background: none;
}
a {
  color: inherit;
  text-decoration: none;
}
button,
a {
  user-select: none;
}
.icon {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.7;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex-shrink: 0;
}
.icon-definitions {
  position: absolute;
  width: 0;
  height: 0;
  overflow: hidden;
}
.app-shell {
  display: flex;
  min-height: 100svh;
}
.sidebar {
  width: 258px;
  flex-shrink: 0;
  position: fixed;
  inset: 0 auto 0 0;
  padding: 37px 22px 25px;
  background: var(--surface);
  border-right: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  z-index: 5;
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  font-size: 27px;
  font-weight: 760;
  letter-spacing: -1.4px;
  margin: 0 9px 56px;
}
.brand-dot {
  color: var(--accent);
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 39px;
  height: 42px;
  border-radius: 12px;
  background: var(--accent);
  color: white;
  box-shadow: 0 4px 9px #6556e820;
}
.brand-mark .icon {
  width: 27px;
  height: 27px;
  stroke-width: 1.8;
}
.sidebar-heading {
  padding: 0 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #8c8fa3;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1.5px;
  margin-bottom: 15px;
}
.tiny-count {
  display: grid;
  place-items: center;
  background: #f2f3f8;
  width: 22px;
  height: 22px;
  border-radius: 6px;
  font-size: 12px;
  letter-spacing: 0;
}
.deck-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.deck-button {
  width: 100%;
  text-align: left;
  padding: 13px 12px;
  display: flex;
  align-items: center;
  gap: 12px;
  border: 1px solid transparent;
  border-radius: 13px;
  transition:
    background 0.2s,
    border-color 0.2s;
}
.deck-button:hover {
  background: #f7f7fc;
}
.deck-button.selected {
  background: #f1efff;
  border-color: #e1dcff;
}
.deck-icon {
  width: 42px;
  height: 44px;
  border-radius: 11px;
  display: grid;
  place-items: center;
  flex-shrink: 0;
}
.deck-icon.education {
  color: #7664e3;
  background: #e6e1ff;
}
.deck-icon.sport {
  color: #e1964a;
  background: #fff0da;
}
.deck-icon .icon {
  width: 24px;
  height: 24px;
}
.deck-info {
  display: flex;
  flex-direction: column;
  gap: 4px;
  flex: 1;
}
.deck-info strong {
  font-size: 15px;
  font-weight: 650;
}
.deck-info small {
  font-size: 12px;
  color: var(--muted);
  font-weight: 450;
}
.deck-button.selected strong {
  color: #5d4bcd;
}
.deck-chevron {
  width: 15px;
  height: 15px;
  color: var(--accent);
  opacity: 0;
}
.selected .deck-chevron {
  opacity: 1;
}
.sidebar-total {
  margin: 22px 13px 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: #989aac;
  gap: 8px;
}
.sidebar-total strong {
  color: #767a91;
  font-weight: 500;
  white-space: nowrap;
}
.sidebar-bottom {
  margin: auto 12px 0;
  padding-top: 40px;
  color: #8f93a7;
  display: flex;
  gap: 10px;
  align-items: flex-start;
}
.sidebar-bottom .icon {
  width: 17px;
  height: 17px;
  margin-top: 3px;
}
.sidebar-bottom p {
  font-size: 12px;
  line-height: 1.7;
  margin: 0;
}
.workspace {
  margin-left: 258px;
  flex: 1;
  min-width: 0;
}
.topbar {
  height: 90px;
  background: #ffffffa6;
  border-bottom: 1px solid var(--line);
  padding: 0 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 13px;
  font-size: 13px;
  color: #9093a5;
}
.breadcrumb .icon {
  width: 13px;
  height: 13px;
  color: #b2b5c3;
}
.breadcrumb strong {
  font-weight: 500;
  color: #51556c;
}
.language-pill {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 12px;
  color: #74788e;
  white-space: nowrap;
}
.language-dot {
  width: 29px;
  height: 29px;
  display: grid;
  place-items: center;
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-size: 12px;
  font-weight: 650;
  color: #78738e;
}
.pill-separator {
  color: #c6c7d2;
}
.main {
  padding: 40px 44px 20px;
  outline: none;
}
.study {
  max-width: 872px;
  margin: auto;
}
.section-heading {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  margin-bottom: 29px;
}
.section-eyebrow {
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 11px;
  font-weight: 680;
  letter-spacing: 1.7px;
  margin-bottom: 10px;
}
.section-eyebrow .icon {
  width: 17px;
  height: 17px;
}
h1 {
  margin: 0 0 8px;
  font-size: 38px;
  font-weight: 680;
  line-height: 1.2;
  letter-spacing: -1.4px;
}
.section-heading p {
  font-size: 14px;
  margin: 0;
  line-height: 1.6;
  color: #7f839a;
}
.section-heading p span {
  color: #9699ac;
  margin-left: 5px;
}
.direction-button {
  background: white;
  border: 1px solid #e5e6f0;
  border-radius: 10px;
  padding: 11px 14px;
  box-shadow: 0 2px 4px #33304c03;
  margin-top: 24px;
  transition:
    border-color 0.2s,
    background 0.2s;
}
.direction-button:hover {
  border-color: #c8c0f7;
  background: #fcfbff;
}
.direction-button > span {
  display: flex;
  gap: 12px;
  align-items: center;
  font-size: 12px;
  font-weight: 650;
  letter-spacing: 0.5px;
}
.direction-button .icon {
  width: 17px;
  height: 17px;
  color: #8f89ad;
}
.study-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 22px;
  gap: 12px;
}
.filter-group {
  display: flex;
  gap: 4px;
  background: #eeeff6;
  padding: 5px;
  border: 1px solid #e9eaf2;
  border-radius: 12px;
}
.filter-button {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  font-size: 13px;
  color: #8a8da3;
  border-radius: 8px;
  transition:
    color 0.2s,
    background 0.2s;
  white-space: nowrap;
}
.filter-button.active {
  color: #5e50ca;
  background: white;
  box-shadow: 0 2px 5px #23254c08;
}
.filter-button > span {
  font-size: 11px;
  font-weight: 600;
  background: #e3e4ee;
  color: #9092a4;
  border-radius: 5px;
  padding: 2px 5px;
  min-width: 20px;
}
.filter-button.active > span {
  color: #7867d4;
  background: #eeebff;
}
.filter-button .icon {
  width: 15px;
  height: 15px;
}
.mode-label {
  font-size: 12px;
  color: #979aad;
}
.study-stage {
  position: relative;
}
.flashcard-area {
  position: relative;
  perspective: 1600px;
  margin: 0 0 5px;
}
.card-underlay {
  position: absolute;
  inset: 15px 15px -9px;
  background: #efedf9;
  border: 1px solid #e9e6f5;
  border-radius: 24px;
  transform: rotate(1.1deg);
  z-index: 0;
}
.flashcard {
  position: relative;
  height: 352px;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.2, 0.75, 0.2, 1);
  z-index: 1;
}
.flashcard.flipped {
  transform: rotateY(180deg);
}
.flashcard.no-transition {
  transition: none;
}
.card-face {
  position: absolute;
  inset: 0;
  border: 1px solid #e7e6f0;
  border-radius: 21px;
  background: white;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  box-shadow:
    0 12px 35px #26235007,
    0 3px 6px #26235003;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.card-back {
  transform: rotateY(180deg);
  background: #fdfcff;
  border-color: #dbd5f8;
}
.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 21px 26px 0;
  flex-shrink: 0;
}
.card-language {
  font-size: 10px;
  font-weight: 650;
  letter-spacing: 1.8px;
  color: #9394a7;
  display: flex;
  align-items: center;
  gap: 9px;
}
.card-language:before {
  content: "";
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #b7acee;
}
.card-actions {
  display: flex;
  gap: 6px;
}
.icon-button {
  display: grid;
  place-items: center;
  width: 35px;
  height: 35px;
  color: #9b9bae;
  border-radius: 9px;
  transition:
    color 0.2s,
    background 0.2s;
}
.icon-button:hover {
  background: #f3f0ff;
  color: var(--accent);
}
.icon-button .icon {
  width: 18px;
  height: 18px;
}
.star-button[aria-pressed="true"] {
  color: #daa633;
  background: #fff7e5;
}
.star-button[aria-pressed="true"] .icon {
  fill: #f8d47b;
  stroke: #d7a127;
}
.speak-button.speaking {
  background: #eeebff;
  color: var(--accent);
  animation: speak-pulse 1s infinite;
}
.card-content {
  flex: 1;
  min-height: 0;
  width: 100%;
  padding: 23px 50px 21px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow-y: auto;
  cursor: pointer;
  user-select: text;
}
.card-content:focus-visible {
  outline-offset: -6px;
  outline-width: 2px;
  border-radius: 10px;
}
.word-text {
  font-weight: 500;
  letter-spacing: -1.3px;
  font-size: 46px;
  line-height: 1.3;
  overflow-wrap: anywhere;
  white-space: pre-wrap;
  display: block;
  margin: auto;
  max-width: 100%;
}
.word-text.medium {
  font-size: 34px;
  letter-spacing: -0.7px;
}
.word-text.long {
  font-size: 25px;
  letter-spacing: -0.35px;
  line-height: 1.45;
}
.word-text.very-long {
  font-size: 19px;
  letter-spacing: 0;
  line-height: 1.55;
}
.card-back .word-text {
  color: #5a4aba;
}
.card-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 0 28px 24px;
  flex-shrink: 0;
  font-size: 11px;
  color: #b0b0c0;
}
.card-number {
  font-variant-numeric: tabular-nums;
  width: 72px;
  letter-spacing: 0.5px;
}
.flip-hint {
  display: flex;
  align-items: center;
  gap: 7px;
  color: #a4a2b8;
  font-size: 12px;
}
.flip-hint .icon {
  width: 15px;
  height: 15px;
}
.card-side-mark {
  width: 72px;
  text-align: right;
  letter-spacing: 1px;
  color: #c3c1d3;
  font-weight: 550;
}
.navigation {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 26px;
  margin-top: 30px;
}
.nav-button {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: white;
  border: 1px solid #e3e4ee;
  color: #74768b;
  transition:
    background 0.2s,
    transform 0.2s,
    box-shadow 0.2s;
}
.nav-button:hover:not(:disabled) {
  background: #efedff;
  transform: translateY(-2px);
}
.nav-next {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
  box-shadow: 0 5px 12px #6556e825;
}
.nav-next:hover:not(:disabled) {
  background: var(--accent-dark);
  box-shadow: 0 7px 15px #6556e835;
}
.nav-button .icon {
  width: 21px;
  height: 21px;
}
.progress-group {
  width: 155px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
}
.progress-group p {
  margin: 0;
  display: flex;
  align-items: center;
  gap: 9px;
  color: #9294aa;
  font-size: 13px;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}
.progress-group strong {
  color: #565570;
  font-weight: 650;
}
.progress-group p > span:first-of-type {
  color: #c7c7d4;
}
.progress-track {
  height: 4px;
  width: 100%;
  background: #e6e5ef;
  overflow: hidden;
  border-radius: 10px;
}
.progress-track > span {
  display: block;
  height: 100%;
  min-width: 5px;
  border-radius: 10px;
  background: #8d7bec;
  transition: width 0.3s;
}
.practice-tools {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 19px;
  margin-top: 29px;
  padding-bottom: 24px;
  border-bottom: 1px solid #e8e9f1;
}
.tool-button {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #87889f;
  font-size: 12px;
  padding: 9px 11px;
  border-radius: 8px;
  white-space: nowrap;
  transition:
    background 0.2s,
    color 0.2s;
}
.tool-button .icon {
  width: 16px;
  height: 16px;
}
.tool-button:hover,
.tool-button[aria-pressed="true"] {
  background: #eeebff;
  color: #6957d7;
}
.tool-button[aria-pressed="true"] {
  box-shadow: inset 0 0 0 1px #e0dafb;
}
.tool-divider {
  width: 1px;
  height: 17px;
  background: #dedfea;
  margin: 0 3px;
}
.keyboard-help {
  display: flex;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 21px;
  margin-top: 23px;
  color: #a1a3b6;
  font-size: 11px;
}
.keyboard-help > span {
  display: flex;
  align-items: center;
  gap: 6px;
}
kbd {
  display: inline-grid;
  place-items: center;
  min-width: 21px;
  height: 21px;
  padding: 0 5px;
  background: #fcfcfe;
  border: 1px solid #e2e3ec;
  border-bottom-width: 2px;
  border-radius: 5px;
  color: #9293a7;
  font: 10px var(--font);
}
.study-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 37px;
  color: #b9bbca;
  font-size: 11px;
}
.mini-brand {
  font-weight: 750;
  letter-spacing: -0.6px;
  font-size: 15px;
  color: #b1b1c5;
}
.toast {
  position: fixed;
  bottom: 25px;
  left: calc(50% + 129px);
  transform: translate(-50%, 15px);
  background: #302d49;
  color: white;
  box-shadow: 0 8px 28px #211b4225;
  padding: 13px 20px;
  border-radius: 12px;
  font-size: 14px;
  max-width: min(90vw, 500px);
  width: max-content;
  z-index: 30;
  opacity: 0;
  pointer-events: none;
  transition:
    opacity 0.2s,
    transform 0.2s;
  text-align: center;
}
.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}
.empty-state {
  min-height: 352px;
  background: white;
  border: 1px solid var(--line);
  border-radius: 21px;
  padding: 54px 20px;
  text-align: center;
}
.empty-state:not([hidden]) {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.empty-icon {
  width: 62px;
  height: 62px;
  background: #f2efff;
  color: #8c7ade;
  border-radius: 19px;
  display: grid;
  place-items: center;
  margin-bottom: 16px;
}
.empty-icon .icon {
  width: 27px;
  height: 27px;
}
.empty-state h2 {
  font-size: 23px;
  letter-spacing: -0.7px;
  margin: 0 0 10px;
}
.empty-state p {
  font-size: 15px;
  line-height: 1.6;
  color: var(--muted);
  margin: 0 0 23px;
}
.primary-button {
  background: var(--accent);
  color: white;
  padding: 12px 19px;
  font-size: 14px;
  border-radius: 10px;
}
.focus-exit {
  display: none;
}
.study-stage.focus-mode,
.study-stage:fullscreen {
  position: fixed;
  inset: 0;
  z-index: 20;
  background: var(--page);
  padding: 8vh max(6vw, calc((100vw - 1000px) / 2));
  overflow: auto;
  display: flex;
  flex-direction: column;
  justify-content: center;
}
.focus-mode .flashcard,
.study-stage:fullscreen .flashcard {
  height: clamp(340px, 60vh, 660px);
}
.focus-mode .focus-exit,
.study-stage:fullscreen .focus-exit {
  display: grid;
  position: absolute;
  top: 20px;
  right: 24px;
  width: 42px;
  height: 42px;
}
.focus-mode .practice-tools,
.study-stage:fullscreen .practice-tools {
  border: 0;
}
.focus-mode .card-content,
.study-stage:fullscreen .card-content {
  padding: 40px;
}
.focus-mode .word-text,
.study-stage:fullscreen .word-text {
  font-size: clamp(30px, 5vw, 64px);
}
.focus-mode .word-text.very-long,
.study-stage:fullscreen .word-text.very-long {
  font-size: clamp(19px, 2.8vw, 30px);
}
body.has-focus {
  overflow: hidden;
}
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.skip-link {
  position: absolute;
  top: -60px;
  left: 20px;
  z-index: 100;
  background: var(--accent);
  color: white;
  padding: 12px;
  border-radius: 8px;
}
.skip-link:focus {
  top: 10px;
}
.noscript {
  position: fixed;
  inset: auto 0 0;
  background: #302d49;
  color: white;
  padding: 20px;
  z-index: 100;
}
[hidden] {
  display: none !important;
}
@keyframes speak-pulse {
  50% {
    box-shadow: 0 0 0 5px #6556e812;
  }
}
@media (min-width: 1500px) {
  .main {
    padding-top: 52px;
  }
  .flashcard {
    height: 400px;
  }
  .section-heading {
    margin-bottom: 34px;
  }
  .study-toolbar {
    margin-bottom: 27px;
  }
  .study-footer {
    margin-top: 40px;
  }
}
@media (max-width: 1100px) {
  .sidebar {
    width: 225px;
    padding-left: 15px;
    padding-right: 15px;
  }
  .workspace {
    margin-left: 225px;
  }
  .main {
    padding: 32px 30px 20px;
  }
  .topbar {
    padding: 0 32px;
  }
  .brand {
    font-size: 25px;
  }
  .deck-button {
    padding: 12px 9px;
    gap: 10px;
  }
  .mode-label {
    display: none;
  }
  .toast {
    left: calc(50% + 112px);
  }
  .word-text {
    font-size: 40px;
  }
}
@media (max-width: 800px) {
  .app-shell {
    display: block;
  }
  .sidebar {
    position: relative;
    inset: auto;
    width: auto;
    padding: 21px 24px 18px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 20px;
  }
  .brand {
    margin: 0;
    font-size: 25px;
    gap: 9px;
  }
  .brand-mark {
    width: 34px;
    height: 36px;
    border-radius: 10px;
  }
  .brand-mark .icon {
    width: 23px;
    height: 23px;
  }
  .sidebar-heading {
    display: none;
  }
  .deck-list {
    grid-column: 1/-1;
    flex-direction: row;
    gap: 12px;
  }
  .deck-button {
    flex: 1;
    padding: 12px 14px;
    gap: 11px;
    border-color: var(--line);
    min-width: 0;
  }
  .deck-icon {
    width: 37px;
    height: 38px;
  }
  .deck-icon .icon {
    width: 22px;
    height: 22px;
  }
  .deck-info strong {
    font-size: 14px;
  }
  .deck-info small {
    font-size: 12px;
  }
  .sidebar-total {
    grid-row: 1;
    grid-column: 2;
    margin: 0;
    border: 0;
    padding: 0;
    align-items: center;
  }
  .sidebar-total > span {
    display: none;
  }
  .sidebar-total strong {
    padding: 6px 10px;
    background: #f7f7fc;
    border-radius: 8px;
  }
  .sidebar-bottom {
    display: none;
  }
  .workspace {
    margin-left: 0;
  }
  .topbar {
    height: 59px;
    padding: 0 27px;
  }
  .language-pill {
    font-size: 11px;
    gap: 6px;
  }
  .language-dot {
    display: none;
  }
  .main {
    padding: 28px 26px 20px;
  }
  .study {
    max-width: 640px;
  }
  .section-heading {
    margin-bottom: 23px;
  }
  h1 {
    font-size: 32px;
  }
  .section-eyebrow {
    font-size: 10px;
    margin-bottom: 8px;
  }
  .direction-button {
    margin-top: 12px;
  }
  .flashcard {
    height: 350px;
  }
  .card-top {
    padding: 19px 21px 0;
  }
  .card-content {
    padding: 20px 27px;
  }
  .card-bottom {
    padding: 0 22px 22px;
  }
  .card-number {
    width: 50px;
  }
  .card-side-mark {
    width: 35px;
  }
  .flip-hint {
    font-size: 11px;
  }
  .word-text {
    font-size: 39px;
  }
  .word-text.medium {
    font-size: 30px;
  }
  .word-text.long {
    font-size: 23px;
  }
  .word-text.very-long {
    font-size: 18px;
  }
  .toast {
    left: 50%;
  }
  .study-footer {
    margin-top: 28px;
  }
  .practice-tools {
    gap: 10px;
  }
  .keyboard-help {
    gap: 13px;
    font-size: 10px;
  }
}
@media (max-width: 480px) {
  .sidebar {
    padding: 19px 18px 17px;
    gap: 18px;
  }
  .deck-list {
    gap: 8px;
  }
  .deck-button {
    padding: 11px 10px;
    gap: 9px;
    border-radius: 11px;
  }
  .deck-chevron {
    display: none;
  }
  .deck-info small {
    font-size: 11px;
  }
  .deck-info strong {
    font-size: 14px;
  }
  .deck-icon {
    width: 34px;
    height: 37px;
    border-radius: 8px;
  }
  .topbar {
    height: 52px;
    padding: 0 21px;
  }
  .breadcrumb {
    font-size: 11px;
    gap: 7px;
  }
  .language-pill {
    font-size: 10px;
    gap: 5px;
  }
  .main {
    padding: 25px 19px 18px;
  }
  .section-heading {
    margin-bottom: 21px;
  }
  .section-heading p {
    font-size: 13px;
    max-width: 235px;
  }
  .section-heading p span {
    display: block;
    margin-left: 0;
  }
  h1 {
    font-size: 32px;
    margin-bottom: 7px;
  }
  .direction-button {
    padding: 10px 11px;
    margin-top: 5px;
  }
  .direction-button > span {
    gap: 8px;
    font-size: 11px;
  }
  .direction-button .icon {
    width: 15px;
    height: 15px;
  }
  .study-toolbar {
    margin-bottom: 19px;
  }
  .filter-group {
    padding: 4px;
    gap: 2px;
    width: 100%;
  }
  .filter-button {
    justify-content: center;
    flex: 1;
    font-size: 12px;
    padding: 9px 8px;
    gap: 7px;
  }
  .flashcard {
    height: 340px;
  }
  .card-face {
    border-radius: 17px;
  }
  .card-underlay {
    inset: 15px 11px -7px;
    border-radius: 19px;
  }
  .card-top {
    padding: 16px 16px 0;
  }
  .card-language {
    font-size: 9px;
    letter-spacing: 1.3px;
    gap: 7px;
  }
  .card-actions {
    gap: 2px;
  }
  .icon-button {
    width: 34px;
    height: 34px;
  }
  .card-content {
    padding: 22px 24px;
  }
  .word-text {
    font-size: 36px;
    letter-spacing: -1px;
  }
  .word-text.medium {
    font-size: 28px;
    letter-spacing: -0.5px;
  }
  .word-text.long {
    font-size: 22px;
    letter-spacing: 0;
  }
  .word-text.very-long {
    font-size: 17px;
    line-height: 1.5;
  }
  .card-bottom {
    padding: 0 18px 19px;
    gap: 5px;
  }
  .card-number {
    font-size: 10px;
    width: 54px;
    letter-spacing: 0;
  }
  .card-side-mark {
    display: none;
  }
  .flip-hint {
    font-size: 10px;
    gap: 5px;
  }
  .flip-hint .icon {
    width: 13px;
    height: 13px;
  }
  .navigation {
    gap: 24px;
    margin-top: 26px;
  }
  .nav-button {
    width: 44px;
    height: 44px;
  }
  .progress-group {
    width: 140px;
  }
  .practice-tools {
    justify-content: space-between;
    gap: 3px;
    margin-top: 21px;
    padding-bottom: 19px;
  }
  .tool-button {
    font-size: 11px;
    gap: 6px;
    padding: 10px 5px;
  }
  .tool-button .icon {
    width: 15px;
    height: 15px;
  }
  .tool-divider {
    margin: 0 1px;
  }
  .keyboard-help {
    display: none;
  }
  .study-footer {
    margin-top: 22px;
    font-size: 10px;
  }
  .mini-brand {
    font-size: 14px;
  }
  .study-stage.focus-mode,
  .study-stage:fullscreen {
    padding: 70px 19px 20px;
    justify-content: center;
  }
  .focus-mode .flashcard,
  .study-stage:fullscreen .flashcard {
    height: 60svh;
    min-height: 300px;
  }
  .focus-mode .card-content,
  .study-stage:fullscreen .card-content {
    padding: 22px;
  }
  .empty-state {
    min-height: 340px;
  }
  .empty-state h2 {
    font-size: 22px;
  }
}
@media (max-width: 355px) {
  .main {
    padding-inline: 13px;
  }
  .sidebar {
    padding-inline: 13px;
  }
  .brand {
    font-size: 23px;
  }
  .deck-button {
    padding: 10px 8px;
    gap: 7px;
  }
  .deck-icon {
    width: 29px;
  }
  .deck-info strong {
    font-size: 13px;
  }
  .deck-info small {
    font-size: 10px;
  }
  .language-pill {
    display: none;
  }
  .tool-button {
    font-size: 10px;
    gap: 4px;
  }
  .card-bottom {
    padding-inline: 14px;
  }
  .flip-hint {
    font-size: 9px;
  }
}
@media (prefers-reduced-motion: reduce) {
  *,
  *:before,
  *:after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}
/* Readable controls and metadata on every screen size. */
.sidebar-heading,
.section-eyebrow {
  font-size: 12px;
}
.deck-info small,
.sidebar-total,
.sidebar-bottom p,
.breadcrumb,
.language-pill,
.mode-label {
  font-size: 12px;
}
.section-heading p {
  font-size: 16px;
}
.direction-button > span {
  font-size: 14px;
}
.filter-button {
  font-size: 14px;
}
.filter-button > span {
  font-size: 12px;
}
.card-language {
  font-size: 12px;
  letter-spacing: 1.4px;
}
.card-number,
.card-bottom,
.flip-hint,
.keyboard-help,
.study-footer {
  font-size: 12px;
}
.tool-button {
  font-size: 14px;
}
.progress-group p {
  font-size: 14px;
}
kbd {
  font-size: 12px;
  min-width: 23px;
  height: 23px;
}
.deck-info strong {
  font-size: 16px;
}
.topbar .breadcrumb {
  font-size: 14px;
}
.word-text {
  font-weight: 480;
}
@media (max-width: 800px) {
  .section-heading p {
    font-size: 14px;
  }
  .practice-tools {
    gap: 5px;
  }
  .tool-button {
    font-size: 14px;
  }
  .keyboard-help {
    gap: 11px;
  }
  .deck-info strong {
    font-size: 15px;
  }
  .deck-info small {
    font-size: 12px;
  }
}
@media (max-width: 480px) {
  .card-language {
    font-size: 12px;
    letter-spacing: 0.6px;
  }
  .card-language:before {
    display: none;
  }
  .card-top {
    padding-top: 15px;
  }
  .card-bottom {
    justify-content: center;
    padding-bottom: 21px;
  }
  .card-number {
    display: none;
  }
  .flip-hint {
    font-size: 12px;
  }
  .filter-button {
    font-size: 14px;
    padding-inline: 7px;
  }
  .tool-button {
    flex-direction: column;
    gap: 7px;
    font-size: 13px;
    padding: 7px 3px;
    flex: 1;
  }
  .tool-button .icon {
    width: 19px;
    height: 19px;
  }
  .tool-divider {
    display: none;
  }
  .practice-tools {
    gap: 5px;
  }
  .section-heading p {
    font-size: 14px;
  }
  .topbar .breadcrumb {
    font-size: 12px;
  }
  .language-pill {
    font-size: 12px;
  }
  .sidebar-total {
    font-size: 12px;
  }
  .deck-info small {
    font-size: 12px;
  }
  .deck-info strong {
    font-size: 14px;
  }
  .direction-button > span {
    font-size: 13px;
  }
  .study-footer {
    font-size: 12px;
  }
  .card-content {
    padding-inline: 23px;
  }
}
@media (max-width: 355px) {
  .tool-button {
    font-size: 12px;
  }
  .deck-info small {
    font-size: 12px;
  }
  .deck-info strong {
    font-size: 14px;
  }
  .deck-icon {
    width: 28px;
  }
  .direction-button > span {
    gap: 6px;
  }
}

.study-footer {
  display: none;
}
.tool-button {
  color: #6b6d85;
}
.filter-button {
  color: #6e7189;
}
.mode-label {
  color: #74788e;
}
.flip-hint {
  color: #7e7b98;
}
.card-language {
  color: #75738b;
}
.sidebar-bottom {
  color: #75798e;
}
.keyboard-help {
  color: #7b7e94;
}
@media (max-width: 480px) {
  .tool-button,
  .direction-button > span {
    font-size: 14px;
  }
  .study-footer {
    display: block;
    text-align: center;
    color: #8a8da3;
    font-size: 12px;
    margin-top: 20px;
    line-height: 1.6;
  }
}

@media (max-width: 480px) {
  .topbar {
    display: none;
  }
  .section-eyebrow {
    display: none;
  }
  .section-heading {
    margin-bottom: 19px;
  }
  .main {
    padding-top: 22px;
  }
  .tool-button {
    white-space: normal;
    text-align: center;
    line-height: 1.3;
  }
}