.concept-hunt-header {
    display: grid;
    gap: 18px;
    margin-bottom: 30px;
}

.concept-hunt-header .back-button {
    justify-self: start;
}

.concept-hunt-header > div {
    max-width: 760px;
}

.concept-hunt-header h1 {
    margin: 5px 0 9px;
}

.concept-hunt-header p:last-child {
    margin: 0;
    color: #5d6a65;
    line-height: 1.6;
}

.concept-hunt {
    display: grid;
    gap: 24px;
}

.concept-hunt-intro {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 28px;
    padding: 25px 28px;
    border: 1px solid #c9dcd3;
    border-radius: 24px;
    background:
        radial-gradient(circle at 92% 12%, rgba(249, 204, 94, 0.22), transparent 27%),
        linear-gradient(145deg, #ffffff, #edf7f2);
    box-shadow: 0 12px 30px rgba(24, 60, 45, 0.07);
}

.concept-hunt-intro h2 {
    margin: 5px 0 7px;
}

.concept-hunt-intro p:last-child {
    max-width: 700px;
    margin: 0;
    color: #5c6c64;
    line-height: 1.55;
}

.concept-hunt-intro > strong {
    display: grid;
    flex: 0 0 96px;
    place-items: center;
    min-height: 86px;
    padding: 12px;
    border-radius: 22px;
    background: #2d7358;
    color: #ffffff;
    font-size: 1.5rem;
    line-height: 1;
    text-align: center;
}

.concept-hunt-intro > strong span {
    font-size: 0.68rem;
    font-weight: 750;
    letter-spacing: 0.06em;
    text-transform: uppercase;
}

.concept-theme-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
}

.concept-theme-card {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 18px;
    min-height: 205px;
    padding: 23px;
    border: 1px solid #d4e0da;
    border-radius: 21px;
    background: linear-gradient(145deg, #ffffff, #f7faf8);
    color: #18201d;
    text-align: left;
    cursor: pointer;
    box-shadow: 0 9px 25px rgba(24, 60, 45, 0.055);
    transition: border-color 150ms ease, box-shadow 150ms ease, transform 150ms ease;
}

.concept-theme-card:hover,
.concept-theme-card:focus-visible {
    border-color: #83b49f;
    box-shadow: 0 15px 32px rgba(24, 60, 45, 0.11);
    transform: translateY(-3px);
}

.concept-theme-card:focus-visible,
.concept-board-card:focus-visible,
.concept-letter:focus-visible {
    outline: 3px solid rgba(45, 115, 88, 0.22);
    outline-offset: 3px;
}

.concept-theme-card__icon {
    display: grid;
    place-items: center;
    width: 62px;
    height: 62px;
    border-radius: 19px;
    background: #e6f3ed;
    font-size: 2rem;
}

.concept-theme-card__body {
    display: flex;
    min-width: 0;
    flex-direction: column;
    align-items: flex-start;
}

.concept-theme-card__body small {
    color: #39715c;
    font-size: 0.7rem;
    font-weight: 850;
    letter-spacing: 0.07em;
    text-transform: uppercase;
}

.concept-theme-card__body > strong {
    margin-top: 5px;
    font-size: 1.14rem;
}

.concept-theme-card__body > span:not(.concept-theme-card__progress) {
    margin-top: 8px;
    color: #5d6a65;
    font-size: 0.87rem;
    line-height: 1.5;
}

.concept-theme-card__progress,
.concept-theme-summary__bar,
.concept-board-toolbar__progress {
    display: block;
    width: 100%;
    height: 7px;
    margin-top: 15px;
    overflow: hidden;
    border-radius: 999px;
    background: #dfeae5;
}

.concept-theme-card__progress i,
.concept-theme-summary__bar i,
.concept-board-toolbar__progress i {
    display: block;
    width: var(--concept-progress);
    height: 100%;
    border-radius: inherit;
    background: #4d9a79;
}

.concept-theme-card__body em {
    margin-top: auto;
    padding-top: 16px;
    color: #2d7358;
    font-size: 0.83rem;
    font-style: normal;
    font-weight: 850;
}

.concept-theme-summary {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) minmax(180px, 0.8fr);
    align-items: center;
    gap: 20px;
    padding: 23px 25px;
    border: 1px solid #c9dcd3;
    border-radius: 22px;
    background: #f5faf7;
}

.concept-theme-summary > span {
    display: grid;
    place-items: center;
    width: 62px;
    height: 62px;
    border-radius: 18px;
    background: #ffffff;
    font-size: 2rem;
    box-shadow: 0 6px 18px rgba(24, 60, 45, 0.08);
}

.concept-theme-summary h2 {
    margin: 4px 0 0;
    font-size: 1.2rem;
}

.concept-theme-summary__bar {
    margin: 0;
    height: 10px;
}

.concept-board-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 15px;
}

.concept-board-card {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 17px;
    min-height: 132px;
    padding: 20px;
    border: 1px solid #d4e0da;
    border-radius: 19px;
    background: #ffffff;
    color: #18201d;
    text-align: left;
    cursor: pointer;
    box-shadow: 0 7px 22px rgba(24, 60, 45, 0.05);
    transition: border-color 150ms ease, transform 150ms ease;
}

.concept-board-card:hover,
.concept-board-card:focus-visible {
    border-color: #83b49f;
    transform: translateY(-2px);
}

.concept-board-card__number {
    display: grid;
    place-items: center;
    width: 48px;
    height: 48px;
    border-radius: 15px;
    background: #e8f4ee;
    color: #2d7358;
    font-size: 1.05rem;
    font-weight: 900;
}

.concept-board-card--complete .concept-board-card__number {
    background: #2d7358;
    color: #ffffff;
}

.concept-board-card > span:last-child {
    display: grid;
    gap: 5px;
}

.concept-board-card small {
    color: #6a7871;
    font-size: 0.72rem;
    font-weight: 750;
    text-transform: uppercase;
}

.concept-board-card strong {
    font-size: 1rem;
}

.concept-board-card em {
    color: #2d7358;
    font-size: 0.8rem;
    font-style: normal;
    font-weight: 800;
}

.concept-board-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 17px 20px;
    border: 1px solid #d3dfd9;
    border-radius: 18px;
    background: #ffffff;
}

.concept-board-toolbar > div {
    display: grid;
    grid-template-columns: auto minmax(130px, 260px);
    align-items: center;
    gap: 16px;
}

.concept-board-toolbar > div > span:first-child {
    color: #53635b;
    font-size: 0.88rem;
    font-weight: 700;
    white-space: nowrap;
}

.concept-board-toolbar > div > span:first-child strong {
    color: #236148;
    font-size: 1.2rem;
}

.concept-board-toolbar__progress {
    margin: 0;
}

.concept-hint-button {
    min-height: 42px;
    padding: 9px 14px;
}

.concept-instructions {
    margin: -10px 0 -5px;
    color: #64736c;
    font-size: 0.86rem;
    line-height: 1.5;
}

.concept-game-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(280px, 0.75fr);
    align-items: start;
    gap: 22px;
}

.concept-letter-panel,
.concept-word-bank {
    border: 1px solid #d4e0da;
    border-radius: 22px;
    background: #ffffff;
    box-shadow: 0 10px 27px rgba(24, 60, 45, 0.055);
}

.concept-letter-panel {
    display: grid;
    justify-items: center;
    gap: 12px;
    padding: clamp(12px, 2.5vw, 24px);
}

.concept-letter-grid {
    display: grid;
    grid-template-columns: repeat(var(--concept-grid-size), minmax(0, 1fr));
    gap: clamp(2px, 0.55vw, 6px);
    width: min(100%, 630px);
    touch-action: none;
    user-select: none;
    -webkit-user-select: none;
}

.concept-letter {
    display: grid;
    place-items: center;
    min-width: 0;
    aspect-ratio: 1;
    padding: 0;
    border: 1px solid #d3e1da;
    border-radius: clamp(5px, 1vw, 10px);
    background: #f7faf8;
    color: #21342c;
    font-family: inherit;
    font-size: clamp(0.7rem, 2.2vw, 1.12rem);
    font-weight: 850;
    cursor: pointer;
    transition: background-color 100ms ease, border-color 100ms ease, color 100ms ease, transform 100ms ease;
}

.concept-letter:hover {
    border-color: #84b49f;
    background: #edf7f2;
}

.concept-letter--selected {
    border-color: #e4ae2f;
    background: #ffdf82;
    color: #332607;
    transform: scale(1.04);
}

.concept-letter--found {
    border-color: #3e8b6c;
    background: #67ad8f;
    color: #ffffff;
}

.concept-letter--found.concept-letter--selected {
    border-color: #e4ae2f;
    background: #ffdf82;
    color: #332607;
}

.concept-letter--hint {
    animation: concept-hint-pulse 600ms ease-in-out 3;
    border-color: #d89d12;
    background: #ffe9a9;
    color: #332607;
}

@keyframes concept-hint-pulse {
    50% { transform: scale(1.09); box-shadow: 0 0 0 4px rgba(232, 178, 43, 0.2); }
}

.concept-selection-status {
    min-height: 24px;
    margin: 0;
    color: #49675a;
    font-size: 0.82rem;
    font-weight: 700;
    line-height: 1.45;
    text-align: center;
}

.concept-word-bank {
    overflow: hidden;
}

.concept-word-bank__heading {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
    padding: 20px;
    border-bottom: 1px solid #dce5e0;
    background: #f7faf8;
}

.concept-word-bank__heading h2 {
    margin: 4px 0 0;
    font-size: 1.05rem;
}

.concept-word-bank__heading > span {
    padding: 7px 10px;
    border-radius: 999px;
    background: #e4f1eb;
    color: #2d7358;
    font-size: 0.76rem;
    font-weight: 850;
}

.concept-word-bank ul {
    display: grid;
    margin: 0;
    padding: 0;
    list-style: none;
}

.concept-word-bank li {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    gap: 11px;
    padding: 15px 18px;
    border-bottom: 1px solid #e3e9e6;
}

.concept-word-bank li:last-child {
    border-bottom: 0;
}

.concept-word-bank li > span {
    color: #91a099;
    font-weight: 900;
}

.concept-word-bank li strong {
    color: #34423c;
    font-size: 0.9rem;
    letter-spacing: 0.025em;
    text-transform: uppercase;
}

.concept-word-bank li p {
    margin: 5px 0 0;
    color: #5e6d66;
    font-size: 0.78rem;
    line-height: 1.45;
}

.concept-word-bank li.concept-word--found {
    background: #f1f8f4;
}

.concept-word-bank li.concept-word--found > span,
.concept-word-bank li.concept-word--found strong {
    color: #2d7358;
}

.concept-word-bank li.concept-word--found strong {
    text-decoration: line-through;
    text-decoration-thickness: 2px;
}

.concept-complete {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr) auto;
    align-items: center;
    gap: 20px;
    padding: 23px 25px;
    border: 1px solid #9fcbb8;
    border-radius: 22px;
    background:
        radial-gradient(circle at 88% 18%, rgba(255, 218, 112, 0.26), transparent 32%),
        linear-gradient(145deg, #fafffc, #e9f7f0);
}

.concept-complete > span {
    font-size: 2.4rem;
}

.concept-complete h2 {
    margin: 4px 0 6px;
    font-size: 1.25rem;
}

.concept-complete p:last-child {
    margin: 0;
    color: #5b6c64;
    font-size: 0.88rem;
    line-height: 1.5;
}

@media (max-width: 820px) {
    .concept-game-layout {
        grid-template-columns: 1fr;
    }

    .concept-word-bank ul {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .concept-word-bank li:nth-child(odd):not(:last-child) {
        border-right: 1px solid #e3e9e6;
    }

    .concept-complete {
        grid-template-columns: auto minmax(0, 1fr);
    }

    .concept-complete .primary-button {
        grid-column: 1 / -1;
        width: 100%;
    }
}

@media (max-width: 650px) {
    .concept-hunt-header {
        margin-bottom: 22px;
    }

    .concept-hunt-intro {
        align-items: flex-start;
        padding: 21px;
    }

    .concept-hunt-intro > strong {
        flex-basis: 74px;
        min-height: 72px;
        font-size: 1.2rem;
    }

    .concept-theme-grid,
    .concept-board-list {
        grid-template-columns: 1fr;
    }

    .concept-theme-card {
        min-height: 180px;
        padding: 19px;
    }

    .concept-theme-card__icon {
        width: 52px;
        height: 52px;
        font-size: 1.65rem;
    }

    .concept-theme-summary {
        grid-template-columns: auto minmax(0, 1fr);
        padding: 19px;
    }

    .concept-theme-summary__bar {
        grid-column: 1 / -1;
    }

    .concept-board-toolbar {
        align-items: stretch;
        flex-direction: column;
    }

    .concept-board-toolbar > div {
        grid-template-columns: auto minmax(90px, 1fr);
    }

    .concept-hint-button {
        width: 100%;
    }

    .concept-word-bank ul {
        grid-template-columns: 1fr;
    }

    .concept-word-bank li:nth-child(odd):not(:last-child) {
        border-right: 0;
    }

    .concept-letter-panel {
        margin-inline: -7px;
        border-radius: 18px;
    }

    .concept-letter {
        font-size: clamp(0.68rem, 3.5vw, 0.92rem);
    }
}

html[data-theme="dark"] .concept-hunt-header p:last-child,
html[data-theme="dark"] .concept-hunt-intro p:last-child,
html[data-theme="dark"] .concept-instructions,
html[data-theme="dark"] .concept-complete p:last-child {
    color: var(--dark-muted);
}

html[data-theme="dark"] :where(
    .concept-hunt-intro,
    .concept-theme-card,
    .concept-theme-summary,
    .concept-board-card,
    .concept-board-toolbar,
    .concept-letter-panel,
    .concept-word-bank,
    .concept-complete
) {
    border-color: var(--dark-border);
    background: var(--dark-surface-raised);
    color: var(--dark-text);
    box-shadow: 0 10px 28px rgba(0, 0, 0, 0.22);
}

html[data-theme="dark"] :where(.concept-theme-card, .concept-board-card):hover,
html[data-theme="dark"] :where(.concept-theme-card, .concept-board-card):focus-visible {
    border-color: var(--dark-border-strong);
}

html[data-theme="dark"] :where(.concept-theme-card__icon, .concept-board-card__number) {
    background: var(--dark-surface-soft);
    color: var(--dark-accent);
}

html[data-theme="dark"] .concept-board-card--complete .concept-board-card__number,
html[data-theme="dark"] .concept-hunt-intro > strong {
    background: #397a61;
    color: #ffffff;
}

html[data-theme="dark"] :where(
    .concept-theme-card__body > span:not(.concept-theme-card__progress),
    .concept-board-card small,
    .concept-board-toolbar > div > span:first-child
) {
    color: var(--dark-muted);
}

html[data-theme="dark"] :where(
    .concept-theme-card__body em,
    .concept-board-card em,
    .concept-board-toolbar > div > span:first-child strong
) {
    color: var(--dark-accent);
}

html[data-theme="dark"] :where(
    .concept-theme-card__progress,
    .concept-theme-summary__bar,
    .concept-board-toolbar__progress
) {
    background: #30453c;
}

html[data-theme="dark"] .concept-theme-summary > span {
    background: var(--dark-surface-soft);
    box-shadow: none;
}

html[data-theme="dark"] .concept-letter {
    border-color: var(--dark-border);
    background: #111a16;
    color: var(--dark-text);
}

html[data-theme="dark"] .concept-letter:hover {
    border-color: #5c8b77;
    background: var(--dark-surface-soft);
}

html[data-theme="dark"] .concept-letter--found {
    border-color: #64b18f;
    background: #397a61;
    color: #ffffff;
}

html[data-theme="dark"] :where(.concept-letter--selected, .concept-letter--hint),
html[data-theme="dark"] .concept-letter--found.concept-letter--selected {
    border-color: #e4ae2f;
    background: #d6a52e;
    color: #211a08;
}

html[data-theme="dark"] .concept-selection-status {
    color: #a8d8c2;
}

html[data-theme="dark"] .concept-word-bank__heading {
    border-color: var(--dark-border);
    background: var(--dark-surface-soft);
}

html[data-theme="dark"] .concept-word-bank__heading > span {
    background: #30483e;
    color: #a6dec6;
}

html[data-theme="dark"] .concept-word-bank li {
    border-color: var(--dark-border);
}

html[data-theme="dark"] .concept-word-bank li strong {
    color: var(--dark-text);
}

html[data-theme="dark"] .concept-word-bank li p {
    color: var(--dark-muted);
}

html[data-theme="dark"] .concept-word-bank li.concept-word--found {
    background: #1e3029;
}

html[data-theme="dark"] .concept-word-bank li.concept-word--found > span,
html[data-theme="dark"] .concept-word-bank li.concept-word--found strong {
    color: var(--dark-accent);
}

@media (prefers-reduced-motion: reduce) {
    .concept-theme-card,
    .concept-board-card,
    .concept-letter {
        transition: none;
    }

    .concept-letter--hint {
        animation: none;
    }
}