.c4d4u-game-group {
    width: 100%;
    box-sizing: border-box;
    margin: 1.25rem auto;
}

.c4d4u-game-layout-stack .c4d4u-game-item {
    margin: 0 0 2rem;
}

.c4d4u-game-layout-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr));
    gap: 1.5rem;
    align-items: start;
}

.c4d4u-game-layout-grid .c4d4u-puzzle {
    margin-top: 0;
}

.c4d4u-game-reload-wrap {
    display: flex;
    justify-content: center;
    margin: 1.25rem 0 1.75rem;
}

.c4d4u-game-reload-button {
    appearance: none;
    border: 1px solid rgba(0,0,0,.28);
    border-radius: 8px;
    padding: .7rem 1.05rem;
    background: #fff;
    color: #202020;
    font: inherit;
    font-weight: 600;
    cursor: pointer;
}

.c4d4u-game-reload-button:hover {
    background: #f2f2f2;
}

.c4d4u-game-error {
    box-sizing: border-box;
    max-width: 920px;
    margin: 1rem auto;
    padding: .8rem 1rem;
    border-left: 4px solid #b32d2e;
    background: #fff3f3;
}

.c4d4u-pge-admin-form {
    max-width: 1100px;
    padding: 16px;
    background: #fff;
    border: 1px solid #dcdcde;
}

.c4d4u-pge-admin-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(260px, 1fr));
    gap: 14px 18px;
}

.c4d4u-pge-admin-grid label {
    display: flex;
    flex-direction: column;
    gap: 5px;
    font-weight: 600;
}

.c4d4u-pge-admin-grid select,
.c4d4u-pge-admin-grid input {
    width: 100%;
    max-width: none;
}

.c4d4u-pge-admin-preview {
    max-width: 1200px;
    padding: 16px;
    background: #fff;
    border: 1px solid #dcdcde;
}

@media (max-width: 760px) {
    .c4d4u-pge-admin-grid {
        grid-template-columns: 1fr;
    }
}


.c4d4u-game-worksheet-wrap {
    display: flex;
    justify-content: center;
    margin: .75rem 0 1.5rem;
}

.c4d4u-game-worksheet-button {
    display: inline-block;
    border: 1px solid rgba(0,0,0,.28);
    border-radius: 8px;
    padding: .7rem 1.05rem;
    background: #fff;
    color: #202020;
    text-decoration: none;
    font: inherit;
    font-weight: 600;
    cursor: pointer;
}

.c4d4u-game-worksheet-button:hover,
.c4d4u-game-worksheet-button:focus {
    background: #f2f2f2;
    color: #202020;
}

/* Sequential puzzle browser ------------------------------------------------ */
.c4d4u-puzzle-browser {
    width: 100%;
    box-sizing: border-box;
    margin: 1.25rem auto 2rem;
}

.c4d4u-puzzle-browser-controls {
    display: flex;
    flex-wrap: wrap;
    gap: .8rem 1rem;
    align-items: end;
    justify-content: center;
    margin: 0 0 1rem;
}

.c4d4u-puzzle-browser-form {
    display: flex;
    flex-wrap: wrap;
    gap: .65rem;
    align-items: end;
    justify-content: center;
}

.c4d4u-puzzle-browser-form label {
    display: flex;
    flex-direction: column;
    gap: .25rem;
    font-weight: 600;
}

.c4d4u-puzzle-browser-form input {
    width: 9rem;
    max-width: 100%;
    padding: .62rem .7rem;
    font: inherit;
}

.c4d4u-puzzle-browser-form button,
.c4d4u-puzzle-browser-continue,
.c4d4u-puzzle-browser-nav-button {
    box-sizing: border-box;
    border: 1px solid rgba(0,0,0,.28);
    border-radius: 8px;
    padding: .68rem 1rem;
    background: #fff;
    color: #202020;
    text-decoration: none;
    font: inherit;
    font-weight: 600;
}

.c4d4u-puzzle-browser-form button,
.c4d4u-puzzle-browser-nav-button:not(.is-disabled),
.c4d4u-puzzle-browser-continue {
    cursor: pointer;
}

.c4d4u-puzzle-browser-form button:hover,
.c4d4u-puzzle-browser-nav-button:not(.is-disabled):hover,
.c4d4u-puzzle-browser-continue:hover {
    background: #f2f2f2;
    color: #202020;
}

.c4d4u-puzzle-browser-message {
    max-width: 920px;
    box-sizing: border-box;
    margin: .75rem auto;
    padding: .7rem .9rem;
    border-left: 4px solid #dba617;
    background: #fff9e8;
}

.c4d4u-puzzle-browser-progress {
    margin: .75rem auto 1rem;
    text-align: center;
    font-weight: 600;
}

.c4d4u-puzzle-browser-puzzle {
    width: 100%;
}

.c4d4u-puzzle-browser-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: .8rem;
    margin: 1.25rem 0 0;
}

.c4d4u-puzzle-browser-nav-button.is-disabled {
    opacity: .42;
    cursor: default;
}

@media (max-width: 620px) {
    .c4d4u-puzzle-browser-form,
    .c4d4u-puzzle-browser-controls,
    .c4d4u-puzzle-browser-nav {
        flex-direction: column;
        align-items: stretch;
    }
    .c4d4u-puzzle-browser-form label,
    .c4d4u-puzzle-browser-form input,
    .c4d4u-puzzle-browser-form button,
    .c4d4u-puzzle-browser-continue,
    .c4d4u-puzzle-browser-nav-button {
        width: 100%;
        text-align: center;
    }
}

/* V0.06a: HPG1 interactive duplicate game -------------------------------- */
.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-interactive .c4d4u-piece {
    cursor: pointer;
}

.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-interactive .c4d4u-piece .c4d4u-cell {
    transition: fill .16s ease, stroke .16s ease, filter .14s ease, opacity .14s ease;
}

.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-interactive:not(.c4d4u-answer-complete):not(.c4d4u-answer-revealed) .c4d4u-piece:hover .c4d4u-cell,
.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-interactive:not(.c4d4u-answer-complete):not(.c4d4u-answer-revealed) .c4d4u-piece:focus .c4d4u-cell {
    filter: brightness(.90);
    opacity: .96;
}

.c4d4u-interactive-answer .c4d4u-piece:focus {
    outline: none;
}

.c4d4u-interactive-answer .c4d4u-piece-wrong {
    filter: drop-shadow(0 0 7px rgba(200, 45, 45, .72));
}

.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-complete .c4d4u-solution-border {
    stroke: #2f9e54;
    stroke-width: 5;
    stroke-opacity: 1;
}

.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-complete .c4d4u-piece,
.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-revealed .c4d4u-piece {
    cursor: default;
}

.c4d4u-interactive-instruction {
    box-sizing: border-box;
    max-width: 920px;
    margin: .55rem auto .7rem;
    color: #4a4a4a;
    text-align: center;
    font-size: .98rem;
    font-weight: 600;
    line-height: 1.35;
}

.c4d4u-interactive-answer .c4d4u-puzzle-board {
    position: relative;
}

.c4d4u-interactive-feedback {
    box-sizing: border-box;
    position: absolute;
    z-index: 25;
    top: 50%;
    left: 50%;
    width: min(86%, 520px);
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: .65rem;
    padding: .9rem 2.7rem .9rem 1.05rem;
    border: 1px solid rgba(0,0,0,.14);
    border-radius: 12px;
    background: rgba(247,247,247,.96);
    box-shadow: 0 8px 28px rgba(0,0,0,.20);
    color: #303030;
    text-align: center;
    font-weight: 700;
    line-height: 1.35;
    backdrop-filter: blur(3px);
    -webkit-backdrop-filter: blur(3px);
}

.c4d4u-interactive-feedback[hidden] {
    display: none !important;
}

.c4d4u-interactive-feedback-message {
    display: block;
    min-width: 0;
}

.c4d4u-interactive-feedback-close {
    position: absolute;
    top: .28rem;
    right: .38rem;
    display: inline-flex;
    width: 2rem;
    height: 2rem;
    align-items: center;
    justify-content: center;
    padding: 0;
    border: 0;
    border-radius: 999px;
    background: transparent;
    color: inherit;
    font: inherit;
    font-size: 1.45rem;
    font-weight: 500;
    line-height: 1;
    cursor: pointer;
    opacity: .64;
}

.c4d4u-interactive-feedback-close:hover,
.c4d4u-interactive-feedback-close:focus-visible {
    background: rgba(0,0,0,.07);
    opacity: 1;
    outline: none;
}

.c4d4u-interactive-feedback.is-correct {
    border-color: rgba(46, 125, 67, .36);
    background: rgba(239,249,241,.97);
    color: #236837;
}

.c4d4u-interactive-feedback.is-wrong {
    border-color: rgba(186, 118, 0, .34);
    background: rgba(255,248,232,.97);
    color: #805300;
}

.c4d4u-interactive-feedback.is-revealed {
    border-color: rgba(70, 92, 120, .28);
    background: rgba(241,245,248,.97);
    color: #485d73;
}

@media (max-width: 600px) {
    .c4d4u-interactive-instruction {
        margin-top: .45rem;
        margin-bottom: .55rem;
        padding: 0 .35rem;
        font-size: .93rem;
    }

    .c4d4u-interactive-feedback {
        width: min(91%, 460px);
        padding: .78rem 2.45rem .78rem .85rem;
        border-radius: 10px;
        font-size: .96rem;
    }

    .c4d4u-interactive-feedback-close {
        top: .18rem;
        right: .24rem;
        width: 1.85rem;
        height: 1.85rem;
        font-size: 1.3rem;
    }
}

.c4d4u-interactive-answer .c4d4u-solution-button:disabled {
    opacity: .72;
    cursor: default;
}

/* V0.07: attempts + timer -------------------------------------------------- */
.c4d4u-interactive-hud {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: .5rem .75rem;
    max-width: 920px;
    margin: .4rem auto .55rem;
}

.c4d4u-interactive-stat {
    display: inline-flex;
    align-items: baseline;
    gap: .35rem;
    padding: .42rem .72rem;
    border: 1px solid rgba(0,0,0,.13);
    border-radius: 999px;
    background: rgba(248,248,248,.96);
    color: #454545;
    font-size: .96rem;
    line-height: 1.2;
    white-space: nowrap;
}

.c4d4u-interactive-stat strong {
    color: #222;
    font-variant-numeric: tabular-nums;
    min-width: 4.7em;
    text-align: left;
}

.c4d4u-attempts-stat strong {
    min-width: 1.2em;
}

.c4d4u-timer-stat.is-warning {
    font-weight: 700;
}

.c4d4u-timer-stat.is-urgent {
    font-weight: 800;
    transform: scale(1.02);
}

.c4d4u-timer-stat.is-expired {
    font-weight: 800;
}

.c4d4u-interactive-feedback.is-timeout {
    background: rgba(247,247,247,.97);
}

@media (max-width: 520px) {
    .c4d4u-interactive-hud {
        gap: .4rem;
    }
    .c4d4u-interactive-stat {
        padding: .4rem .62rem;
        font-size: .92rem;
    }
}

/* V0.07a: fair start gate -------------------------------------------------- */
.c4d4u-interactive-answer .c4d4u-puzzle.c4d4u-answer-waiting .c4d4u-piece {
    cursor: default;
    pointer-events: none;
}

.c4d4u-interactive-start-overlay {
    box-sizing: border-box;
    position: absolute;
    z-index: 35;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    padding: 1.25rem;
    border-radius: 10px;
    background: rgba(247,247,247,.992);
    color: #2d2d2d;
    text-align: center;
}

.c4d4u-interactive-start-overlay[hidden] {
    display: none !important;
}

.c4d4u-interactive-start-ready {
    font-size: clamp(1.25rem, 3vw, 2rem);
    font-weight: 750;
    line-height: 1.2;
}

.c4d4u-interactive-start-countdown {
    min-width: 1.7em;
    font-size: clamp(2.8rem, 9vw, 5.5rem);
    font-weight: 850;
    line-height: 1;
    font-variant-numeric: tabular-nums;
}

.c4d4u-interactive-start-countdown.is-go {
    font-size: clamp(2.1rem, 7vw, 4.1rem);
}

.c4d4u-interactive-start-button {
    min-width: 8.5rem;
    padding: .72rem 1.25rem;
    border: 1px solid rgba(0,0,0,.2);
    border-radius: 999px;
    background: #fff;
    color: #252525;
    font: inherit;
    font-size: 1.02rem;
    font-weight: 700;
    line-height: 1.2;
    cursor: pointer;
    box-shadow: 0 3px 12px rgba(0,0,0,.10);
}

.c4d4u-interactive-start-button:hover,
.c4d4u-interactive-start-button:focus-visible {
    background: #f0f0f0;
    outline: none;
}

@media (max-width: 520px) {
    .c4d4u-interactive-start-overlay {
        gap: .8rem;
        padding: .9rem;
    }
    .c4d4u-interactive-start-button {
        min-width: 7.4rem;
        padding: .65rem 1rem;
    }
}