.kne-vocab-app {
    --kne-primary: #082b73;
    --kne-primary-light: #eaf1ff;
    --kne-text: #14233b;
    --kne-muted: #63718a;
    --kne-border: #dfe7f3;
    --kne-surface: #ffffff;
    color: var(--kne-text);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    margin: 24px auto;
    max-width: 980px;
}

.kne-vocab-app *,
.kne-vocab-app *::before,
.kne-vocab-app *::after {
    box-sizing: border-box;
}

.kne-vocab-app [hidden] {
    display: none !important;
}

.kne-vocab-app button,
.kne-vocab-app select {
    font: inherit;
}

.kne-vocab-loading,
.kne-vocab-error {
    align-items: center;
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 22px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 320px;
    padding: 36px;
    text-align: center;
}

.kne-vocab-spinner {
    animation: kne-spin 0.9s linear infinite;
    border: 4px solid #dce7f8;
    border-radius: 50%;
    border-top-color: var(--kne-primary);
    height: 44px;
    width: 44px;
}

@keyframes kne-spin {
    to { transform: rotate(360deg); }
}

.kne-vocab-shell {
    background: #f5f8fd;
    border: 1px solid var(--kne-border);
    border-radius: 26px;
    box-shadow: 0 18px 55px rgba(20, 35, 59, 0.1);
    min-height: 620px;
    overflow: hidden;
}

.kne-vocab-header {
    align-items: center;
    background: var(--kne-primary);
    color: #fff;
    display: flex;
    justify-content: space-between;
    padding: 24px 30px;
}

.kne-vocab-header h1 {
    color: inherit;
    font-size: clamp(1.6rem, 4vw, 2.2rem);
    line-height: 1.1;
    margin: 4px 0 0;
}

.kne-game-status {
    align-items: center;
    display: flex;
    gap: 8px;
}

.kne-game-status > span {
    align-items: center;
    background: rgba(255, 255, 255, 0.13);
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 999px;
    display: flex;
    gap: 5px;
    min-width: 62px;
    padding: 8px 11px;
}

.kne-game-status b {
    font-size: 1rem;
    line-height: 1;
}

.kne-game-status strong {
    color: #fff;
    font-size: 0.9rem;
}

.kne-vocab-eyebrow {
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.12em;
    opacity: 0.76;
    text-transform: uppercase;
}

.kne-vocab-category {
    display: flex;
    flex-direction: column;
    font-size: 0.78rem;
    font-weight: 700;
    gap: 5px;
}

.kne-vocab-category select {
    appearance: auto;
    background: #fff;
    border: 0;
    border-radius: 10px;
    color: var(--kne-text);
    min-width: 180px;
    padding: 9px 12px;
}

.kne-vocab-nav {
    background: #fff;
    border-bottom: 1px solid var(--kne-border);
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    padding: 0 20px;
}

.kne-vocab-nav button {
    appearance: none;
    background: transparent;
    border: 0;
    border-bottom: 3px solid transparent;
    color: var(--kne-muted);
    cursor: pointer;
    font-weight: 700;
    padding: 17px 10px 14px;
}

.kne-vocab-nav button:hover,
.kne-vocab-nav button:focus-visible,
.kne-vocab-nav button.is-active {
    border-bottom-color: var(--kne-primary);
    color: var(--kne-primary);
}

.kne-vocab-view {
    animation: kne-fade 0.22s ease-out;
    padding: 28px;
}

@keyframes kne-fade {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: none; }
}

.kne-vocab-stats {
    display: grid;
    gap: 14px;
    grid-template-columns: repeat(4, 1fr);
    margin-top: 24px;
}

.kne-daily-goal {
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 18px;
    padding: 18px 20px;
}

.kne-daily-goal .kne-progress {
    margin-top: 13px;
    width: 100%;
}

.kne-daily-goal__heading,
.kne-daily-goal__heading > div {
    align-items: center;
    display: flex;
    justify-content: space-between;
}

.kne-daily-goal__heading > div {
    flex: 1;
    gap: 12px;
}

.kne-daily-goal__heading span:first-child {
    color: var(--kne-text);
    font-weight: 800;
}

.kne-daily-goal__heading strong {
    color: var(--kne-primary);
    font-size: 0.9rem;
}

.kne-daily-goal__badge {
    align-items: center;
    background: #fff4c9;
    border-radius: 50%;
    display: flex;
    height: 38px;
    justify-content: center;
    margin-left: 14px;
    width: 38px;
}

.kne-daily-goal__badge.is-complete {
    background: #e7f8ec;
}

.kne-learning-path {
    background: linear-gradient(180deg, #f7faff 0%, #eef4ff 100%);
    border: 1px solid var(--kne-border);
    border-radius: 22px;
    margin-top: 20px;
    overflow: hidden;
    padding: 24px;
}

.kne-section-heading {
    align-items: flex-end;
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
}

.kne-section-heading .kne-vocab-eyebrow {
    color: var(--kne-primary);
}

.kne-section-heading h2 {
    color: var(--kne-text);
    margin: 3px 0 0;
}

.kne-section-heading p {
    color: var(--kne-muted);
    font-size: 0.86rem;
    margin: 0;
}

.kne-path-list {
    margin: 0 auto;
    max-width: 560px;
    padding: 8px 0;
}

.kne-path-node {
    align-items: center;
    display: grid;
    gap: 16px;
    grid-template-columns: 86px minmax(0, 1fr);
    min-height: 112px;
    position: relative;
    transition: transform 0.2s ease;
}

.kne-path-node:nth-child(3n + 2) {
    transform: translateX(68px);
}

.kne-path-node:nth-child(3n + 3) {
    transform: translateX(26px);
}

.kne-path-node__connector {
    background: #cbd8ec;
    height: 36px;
    left: 41px;
    position: absolute;
    top: -18px;
    width: 4px;
}

.kne-path-node:first-child .kne-path-node__connector {
    display: none;
}

.kne-path-node__button {
    align-items: center;
    appearance: none;
    background: linear-gradient(145deg, #157ee8, var(--kne-primary));
    border: 0;
    border-bottom: 7px solid #051e55;
    border-radius: 50%;
    color: #fff;
    cursor: pointer;
    display: flex;
    font-size: 2rem;
    height: 82px;
    justify-content: center;
    position: relative;
    width: 82px;
    z-index: 1;
}

.kne-path-node__button:hover:not(:disabled),
.kne-path-node__button:focus-visible:not(:disabled) {
    filter: brightness(1.08);
    transform: translateY(-2px);
}

.kne-path-node.is-complete .kne-path-node__button {
    background: linear-gradient(145deg, #ffc928, #e89d00);
    border-bottom-color: #b67700;
}

.kne-path-node.is-locked .kne-path-node__button {
    background: #d4dce9;
    border-bottom-color: #aeb9ca;
    cursor: not-allowed;
    filter: grayscale(0.25);
}

.kne-path-node__copy {
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 15px;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    padding: 13px 16px;
}

.kne-path-node.is-locked .kne-path-node__copy {
    cursor: default;
    opacity: 0.65;
}

.kne-path-node__copy > span {
    color: var(--kne-primary);
    font-size: 0.72rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.kne-path-node__copy strong {
    color: var(--kne-text);
    font-size: 1.08rem;
    margin-top: 2px;
}

.kne-path-node__copy small {
    color: var(--kne-muted);
    margin-top: 3px;
}

.kne-path-node__stars {
    color: #f1ad00;
    font-size: 1.05rem;
    letter-spacing: 0.1em;
    margin-top: 4px;
}

.kne-vocab-stats article {
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 16px;
    padding: 18px;
    text-align: center;
}

.kne-vocab-stats strong {
    color: var(--kne-primary);
    display: block;
    font-size: 1.8rem;
    line-height: 1;
}

.kne-vocab-stats span {
    color: var(--kne-muted);
    display: block;
    font-size: 0.82rem;
    margin-top: 8px;
}

.kne-vocab-hero {
    align-items: center;
    background: linear-gradient(135deg, var(--kne-primary), #157ee8);
    border-radius: 22px;
    color: #fff;
    display: flex;
    justify-content: space-between;
    margin-top: 20px;
    overflow: hidden;
    padding: 28px 32px;
    position: relative;
}

.kne-vocab-hero::after {
    background: rgba(255, 255, 255, 0.09);
    border-radius: 50%;
    content: "";
    height: 210px;
    position: absolute;
    right: -65px;
    top: -90px;
    width: 210px;
}

.kne-vocab-hero > * {
    position: relative;
    z-index: 1;
}

.kne-vocab-hero h2 {
    color: inherit;
    font-size: 1.5rem;
    margin: 7px 0;
}

.kne-vocab-hero p {
    margin: 0;
    opacity: 0.82;
}

.kne-vocab-hero__icon {
    font-size: 2rem;
}

.kne-vocab-home-actions {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(2, 1fr);
    margin-top: 20px;
}

.kne-action-card {
    align-items: flex-start;
    appearance: none;
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 18px;
    color: var(--kne-text);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    padding: 20px;
    text-align: left;
}

.kne-action-card:hover,
.kne-action-card:focus-visible {
    border-color: var(--kne-primary);
    box-shadow: 0 10px 28px rgba(8, 43, 115, 0.1);
}

.kne-action-card > span {
    font-size: 1.8rem;
}

.kne-action-card strong {
    font-size: 1.08rem;
    margin-top: 8px;
}

.kne-action-card small {
    color: var(--kne-muted);
    margin-top: 3px;
}

.kne-button {
    appearance: none;
    border: 0;
    border-radius: 999px;
    cursor: pointer;
    font-weight: 800;
    line-height: 1.2;
    padding: 12px 20px;
}

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

.kne-vocab-hero .kne-button--primary {
    background: #ffd54a;
    color: #16233a;
}

.kne-button--soft {
    background: var(--kne-primary-light);
    color: var(--kne-primary);
}

.kne-button--danger {
    background: #fff0f1;
    color: #c63545;
}

.kne-button--success {
    background: #e8f8ee;
    color: #13753a;
}

.kne-button:hover,
.kne-button:focus-visible {
    filter: brightness(0.96);
    transform: translateY(-1px);
}

.kne-learn-toolbar,
.kne-quiz-toolbar {
    align-items: center;
    display: flex;
    gap: 16px;
    justify-content: space-between;
    margin: 0 auto 16px;
    max-width: 620px;
}

.kne-progress {
    background: #dfe7f3;
    border-radius: 999px;
    height: 8px;
    overflow: hidden;
    width: min(70%, 420px);
}

.kne-progress span {
    background: linear-gradient(90deg, var(--kne-primary), #25a3ff);
    border-radius: inherit;
    display: block;
    height: 100%;
    transition: width 0.25s ease;
    width: 0;
}

.kne-flashcard,
.kne-quiz-card {
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 24px;
    box-shadow: 0 15px 38px rgba(20, 35, 59, 0.08);
    margin: 0 auto;
    max-width: 620px;
    padding: 26px;
    text-align: center;
}

.kne-word-visual {
    align-items: center;
    background: linear-gradient(145deg, #eff6ff, #e5eeff);
    border-radius: 20px;
    display: flex;
    height: 270px;
    justify-content: center;
    overflow: hidden;
}

.kne-word-visual img {
    height: 100%;
    object-fit: cover;
    width: 100%;
}

.kne-word-visual__fallback {
    font-size: clamp(5rem, 18vw, 9rem);
    line-height: 1;
}

.kne-flashcard__word-row {
    align-items: center;
    display: flex;
    justify-content: center;
    margin: 20px 0 16px;
    position: relative;
}

.kne-flashcard__word-row h2 {
    color: var(--kne-text);
    font-size: 2.25rem;
    line-height: 1;
    margin: 0;
}

.kne-flashcard__word-row span {
    color: var(--kne-muted);
    display: block;
    margin-top: 7px;
}

.kne-sound-button {
    align-items: center;
    appearance: none;
    background: var(--kne-primary-light);
    border: 0;
    border-radius: 50%;
    color: var(--kne-primary);
    cursor: pointer;
    display: flex;
    height: 46px;
    justify-content: center;
    margin-left: 16px;
    width: 46px;
}

.kne-sound-button--large {
    border-radius: 999px;
    height: auto;
    margin: 20px auto;
    padding: 14px 22px;
    width: auto;
}

.kne-flashcard__answer {
    background: #f8faff;
    border-radius: 14px;
    margin-top: 18px;
    padding: 16px;
}

.kne-flashcard__answer strong {
    color: var(--kne-primary);
    display: block;
    font-size: 1.35rem;
}

.kne-flashcard__answer p {
    margin: 10px 0 2px;
}

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

.kne-learn-actions {
    display: grid;
    gap: 12px;
    grid-template-columns: 1fr 1fr;
    margin: 18px auto 0;
    max-width: 620px;
}

.kne-card-navigation {
    display: flex;
    justify-content: space-between;
    margin: 15px auto 0;
    max-width: 620px;
}

.kne-card-navigation button {
    appearance: none;
    background: transparent;
    border: 0;
    color: var(--kne-muted);
    cursor: pointer;
    padding: 8px;
}

.kne-quiz-card {
    margin-top: 16px;
}

.kne-quiz-setup {
    min-height: 430px;
}

.kne-quiz-type-picker {
    display: grid;
    gap: 9px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    margin: 0 auto 22px;
    max-width: 620px;
    width: 100%;
}

.kne-quiz-type-picker button {
    appearance: none;
    background: #fff;
    border: 2px solid var(--kne-border);
    border-radius: 13px;
    color: var(--kne-muted);
    cursor: pointer;
    font-weight: 700;
    min-height: 54px;
    padding: 10px 13px;
}

.kne-quiz-type-picker button::before {
    content: "○";
    margin-right: 6px;
}

.kne-quiz-type-picker button.is-active {
    background: var(--kne-primary-light);
    border-color: var(--kne-primary);
    color: var(--kne-primary);
}

.kne-quiz-type-picker button.is-active::before {
    content: "✓";
}

.kne-quiz-prompt {
    color: var(--kne-text);
    font-size: 1.22rem;
    font-weight: 800;
    margin: 0 0 18px;
}

.kne-word-visual--quiz {
    height: 210px;
    margin: 0 auto 20px;
    max-width: 360px;
}

.kne-word-visual--quiz.is-word {
    color: var(--kne-primary);
    font-size: clamp(2rem, 8vw, 3.4rem);
    font-weight: 900;
}

.kne-quiz-options {
    display: grid;
    gap: 11px;
    grid-template-columns: repeat(2, 1fr);
}

.kne-quiz-options button {
    appearance: none;
    background: #fff;
    border: 2px solid var(--kne-border);
    border-radius: 13px;
    color: var(--kne-text);
    cursor: pointer;
    font-weight: 700;
    min-height: 54px;
    padding: 11px;
}

.kne-quiz-options button:hover:not(:disabled),
.kne-quiz-options button:focus-visible:not(:disabled) {
    border-color: var(--kne-primary);
}

.kne-quiz-options button.is-correct {
    background: #e8f8ee;
    border-color: #2ca55d;
    color: #126a35;
}

.kne-quiz-options button.is-wrong {
    background: #fff0f1;
    border-color: #e45b68;
    color: #a52634;
}

.kne-quiz-feedback {
    font-weight: 700;
    min-height: 24px;
}

.kne-quiz-feedback.is-correct { color: #13753a; }
.kne-quiz-feedback.is-wrong { color: #b82d3c; }

.kne-review-heading {
    align-items: center;
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
}

.kne-review-heading h2 {
    margin: 0 0 4px;
}

.kne-review-heading p {
    color: var(--kne-muted);
    margin: 0;
}

.kne-review-list {
    display: grid;
    gap: 10px;
}

.kne-review-start {
    justify-self: start;
    margin-bottom: 8px;
}

.kne-review-item {
    align-items: center;
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 15px;
    display: flex;
    gap: 14px;
    padding: 12px;
}

.kne-review-item__visual {
    align-items: center;
    background: var(--kne-primary-light);
    border-radius: 11px;
    display: flex;
    height: 58px;
    justify-content: center;
    overflow: hidden;
    width: 58px;
}

.kne-review-item__visual img {
    height: 100%;
    object-fit: cover;
    width: 100%;
}

.kne-review-item__visual .kne-word-visual__fallback {
    font-size: 2rem;
}

.kne-review-item strong,
.kne-review-item span {
    display: block;
}

.kne-review-item span {
    color: var(--kne-muted);
    font-size: 0.88rem;
    margin-top: 2px;
}

.kne-empty-state {
    align-items: center;
    background: #fff;
    border: 1px solid var(--kne-border);
    border-radius: 20px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 300px;
    padding: 34px;
    text-align: center;
}

.kne-empty-state > span {
    font-size: 4rem;
}

.kne-empty-state h2,
.kne-empty-state h3 {
    margin: 12px 0 4px;
}

.kne-empty-state p {
    color: var(--kne-muted);
    margin: 4px 0 20px;
}

@media (max-width: 720px) {
    .kne-vocab-app { margin: 12px auto; }
    .kne-vocab-shell { border-radius: 18px; min-height: 600px; }
    .kne-vocab-header { align-items: flex-start; flex-direction: column; gap: 16px; padding: 22px; }
    .kne-game-status { justify-content: space-between; width: 100%; }
    .kne-game-status > span { justify-content: center; flex: 1; }
    .kne-vocab-category,
    .kne-vocab-category select { width: 100%; }
    .kne-vocab-nav { overflow-x: auto; padding: 0; }
    .kne-vocab-nav button { min-width: 82px; padding-inline: 6px; }
    .kne-vocab-view { padding: 18px 14px 24px; }
    .kne-vocab-stats { gap: 8px; grid-template-columns: repeat(2, 1fr); }
    .kne-vocab-stats article { padding: 15px 8px; }
    .kne-section-heading { align-items: flex-start; flex-direction: column; gap: 5px; }
    .kne-learning-path { padding: 18px 12px; }
    .kne-path-node { gap: 10px; grid-template-columns: 72px minmax(0, 1fr); }
    .kne-path-node:nth-child(3n + 2) { transform: translateX(22px); }
    .kne-path-node:nth-child(3n + 3) { transform: translateX(8px); }
    .kne-path-node__button { border-bottom-width: 6px; font-size: 1.65rem; height: 68px; width: 68px; }
    .kne-path-node__connector { left: 33px; }
    .kne-vocab-hero { align-items: flex-start; flex-direction: column; gap: 20px; padding: 24px; }
    .kne-vocab-home-actions { grid-template-columns: 1fr; }
    .kne-word-visual { height: 235px; }
    .kne-flashcard,
    .kne-quiz-card { border-radius: 18px; padding: 16px; }
    .kne-learn-toolbar { align-items: flex-start; flex-direction: column; gap: 8px; }
    .kne-progress { width: 100%; }
    .kne-quiz-options { grid-template-columns: 1fr; }
    .kne-quiz-type-picker { grid-template-columns: 1fr; }
    .kne-review-heading { align-items: flex-start; flex-direction: column; gap: 14px; }
}

@media (max-width: 420px) {
    .kne-flashcard__word-row h2 { font-size: 1.9rem; }
    .kne-learn-actions { grid-template-columns: 1fr; }
    .kne-word-visual { height: 210px; }
}

@media (prefers-reduced-motion: reduce) {
    .kne-vocab-app *,
    .kne-vocab-app *::before,
    .kne-vocab-app *::after {
        animation-duration: 0.01ms !important;
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
    }
}