/*
 * sudoku.css — styling for the Sudoku generator UI.
 *
 * IMPORTANT: style1.css line ~3537 defines a global  button { ... }  rule
 * with padding:10px 15px !important and border-radius:5px !important. All
 * Sudoku buttons therefore need an explicit !important override to claim
 * their own visual identity. We scope every override under .sudoku-page so
 * we never affect unrelated buttons elsewhere on the site.
 *
 * Color palette aligns with the existing DotToDot/Sudoku-tab gold theme
 * (#FFF6D9 / #F5DA8A / #80600F) for visual continuity with the active-tab
 * pill already in the page skeleton.
 */

.sudoku-page {
    /* Inset van de naburige sidebar/content-edge. Alles wat onder
       .sudoku-page valt (header, tabs, toolbar, grid, ...) erft deze
       horizontale marge. Op smalle schermen schaalt dat terug via de
       responsive-rule onderaan dit bestand. */
    padding: 0 28px;

    --sk-gold-bg: #FFF6D9;
    --sk-gold-border: #F5DA8A;
    --sk-gold-text: #80600F;
    --sk-cell-bg: #ffffff;
    --sk-cell-bg-given: #f3f3ef;
    --sk-cell-bg-peer: #f7f4e7;
    --sk-cell-bg-same: #ffe9a8;
    --sk-cell-bg-selected: #ffd966;
    --sk-cell-border: #c8c8be;
    --sk-block-border: #2a2a2a;
    --sk-text-given: #1a1a1a;
    --sk-text-user: #1e6f1e;
    --sk-text-error: #c0392b;
    --sk-text-conflict: #c0392b;
    --sk-note-color: #666;
    --sk-btn-bg: #ffffff;
    --sk-btn-border: #d4d4cd;
    --sk-btn-text: #333;
    --sk-btn-active-bg: var(--sk-gold-bg);
    --sk-btn-active-border: var(--sk-gold-border);
    --sk-btn-active-text: var(--sk-gold-text);
    --sk-btn-disabled-opacity: 0.5;
}

/* ---------- header + intro paragraphs ----------
   Hero-card: witte achtergrond met dunne grijze border. Geen gekleurde
   accent-streep — de mintgroene sudoku-identiteit komt uit het icoon-
   tegeltje zelf, niet uit een tweede gekleurd element. Dat voorkomt
   tinten-concurrentie met de gouden active-state van de toolbar-knoppen
   (#FFF6D9 / #80600F) verderop op dezelfde viewport.

   De `:has(.sudoku-page__icon)`-selector schakelt flex-layout aan
   wanneer er een icoon-element in de header zit. Zonder icoon (zoals
   in solver.php en kids.php op dit moment) blijft het een verticale
   stack — geen scope-impact op niet-bijgewerkte templates. */
.sudoku-page__header {
    background: #ffffff;
    border: 1px solid #E2E1DA;
    border-radius: 12px;
    padding: 24px 28px;
    margin-bottom: 28px;
}
.sudoku-page__header:has(.sudoku-page__icon) {
    display: flex;
    align-items: flex-start;
    gap: 18px;
}
.sudoku-page__icon {
    flex-shrink: 0;
    width: 52px;
    height: 52px;
    background: #E5F0E9;
    border-radius: 10px;
    padding: 8px;
    box-sizing: border-box;
    color: #205437;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.sudoku-page__icon svg {
    display: block;
    width: 100%;
    height: 100%;
    stroke: currentColor;
    stroke-width: 1.7;
    fill: none;
    stroke-linecap: round;
    stroke-linejoin: round;
}
.sudoku-page__header-text {
    flex: 1;
    min-width: 0;
}
.sudoku-page__title {
    margin: 0 0 10px;
    font-size: 28px;
    font-weight: 700;
    color: #1a1a1a;
    line-height: 1.2;
}
.sudoku-page__intro {
    margin: 0 0 8px;
    font-size: 16.5px;
    line-height: 1.55;
    color: #2a2a2a;
}
.sudoku-page__detail {
    margin: 0;
    line-height: 1.6;
    color: #555;
    font-size: 14.5px;
}

/* ---------- layout shells ---------- */

/* Tab-strip (Generator active, Solver/Daily/Kids disabled in fase 1.2).
   Geporteerd uit de oude inline skelet-CSS — kleur-pill matcht de toolbar
   active-state voor visuele consistency. */
.sudoku-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
    align-items: center;
    margin-bottom: 24px;
    border-bottom: 1px solid #e3e3e0;
    padding-bottom: 12px;
}
.sudoku-tab {
    padding: 8px 16px;
    border-radius: 6px;
    font-weight: 500;
    color: #444;
    background: #f1f1ee;
    line-height: 1.2;
    text-align: center;
}
.sudoku-tab--active {
    background: var(--sk-gold-bg);
    color: var(--sk-gold-text);
    border: 1px solid var(--sk-gold-border);
}
/* Kids-tab krijgt extra visuele nadruk: dikkere mintgroene rand, passend bij
   de kleur die we ook gebruiken voor de homepage-card en sidebar-nav-active
   state van sudoku-voor-kinderen. Subtiel maar onderscheidend genoeg om de
   speler te laten zien dat er een aparte kindvriendelijke variant bestaat. */
.sudoku-tab--kids {
    border: 2px solid #3A8159;
    background: #E5F0E9;
    color: #205437;
    font-weight: 600;
    /* Padding -1px compenseren voor de extra border-px zodat de tab dezelfde
       hoogte houdt als de andere tabs in de rij. */
    padding: 7px 15px;
}
.sudoku-tab--kids:hover {
    background: #d6e8dd;
    border-color: #2a6a47;
    color: #123320;
}
.sudoku-tab--disabled {
    opacity: 0.55;
    cursor: not-allowed;
}
.sudoku-tab small {
    display: block;
    font-size: 0.7rem;
    font-weight: 400;
    color: #777;
    margin-top: 2px;
}

.sudoku-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
    justify-content: center;
    align-items: flex-start;
    margin-bottom: 16px;
}

.sudoku-toolbar__group {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.sudoku-toolbar__label {
    font-size: 12px;
    font-weight: 500;
    color: #666;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.sudoku-toolbar__buttons {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
}

.sudoku-status {
    display: flex;
    flex-wrap: wrap;
    gap: 14px 24px;
    justify-content: center;
    margin-bottom: 12px;
    font-size: 14px;
    color: #444;
}
.sudoku-status__item {
    display: inline-flex;
    align-items: baseline;
    gap: 6px;
}
.sudoku-status__label {
    font-weight: 500;
    color: #666;
}
.sudoku-status__value {
    color: #222;
    font-variant-numeric: tabular-nums;
    font-weight: 600;
}

.sudoku-board-wrap {
    max-width: 540px;
    margin: 0 auto 16px;
    padding: 0 4px;
}

/* ---------- grid ---------- */

.sk-grid {
    display: grid;
    width: 100%;
    aspect-ratio: 1 / 1;
    margin: 0 auto;
    background: var(--sk-cell-bg);
    border: 3px solid var(--sk-block-border);
    box-sizing: border-box;
    user-select: none;
    -webkit-user-select: none;
}

/* Per-size: columns, rows, max-width, font-size. CSS Grid distributes
   columns and rows on equal 1fr tracks, so cells are guaranteed square
   inside the aspect-ratio container. */
.sk-grid--4 {
    grid-template-columns: repeat(4, 1fr);
    grid-template-rows: repeat(4, 1fr);
    max-width: 320px;
    font-size: clamp(22px, 7vw, 36px);
}
.sk-grid--6 {
    grid-template-columns: repeat(6, 1fr);
    grid-template-rows: repeat(6, 1fr);
    max-width: 420px;
    font-size: clamp(18px, 5.5vw, 30px);
}
.sk-grid--9 {
    grid-template-columns: repeat(9, 1fr);
    grid-template-rows: repeat(9, 1fr);
    max-width: 540px;
    font-size: clamp(16px, 4.5vw, 26px);
}

.sk-cell {
    display: flex;
    align-items: center;
    justify-content: center;
    box-sizing: border-box;
    border: 1px solid var(--sk-cell-border);
    background: var(--sk-cell-bg);
    font-family: Arial, Helvetica, sans-serif;
    font-weight: 500;
    color: var(--sk-text-user);
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: background-color 0.08s ease;
}
.sk-cell--block-right {
    border-right: 3px solid var(--sk-block-border);
}
.sk-cell--block-bottom {
    border-bottom: 3px solid var(--sk-block-border);
}

/* Cell states */
.sk-cell--given {
    color: var(--sk-text-given);
    background: var(--sk-cell-bg-given);
    font-weight: 700;
    cursor: default;
}
.sk-cell--user {
    color: var(--sk-text-user);
    font-weight: 500;
}
.sk-cell--error {
    color: var(--sk-text-error) !important;
}
.sk-cell--conflict {
    background: #ffe2e0 !important;
}
.sk-cell--peer {
    background: var(--sk-cell-bg-peer);
}
.sk-cell--same-digit {
    background: var(--sk-cell-bg-same);
}
.sk-cell--selected {
    background: var(--sk-cell-bg-selected) !important;
    /* Inset box-shadow i.p.v. outline: een outline tekent OVER de eigen border
       heen, dus op een cel die zelf een dikke blokrand draagt (--block-right/
       --block-bottom) at de gouden outline de zwarte 3px-rand op → lijn lijkt
       onderbroken. Een inset shadow laat de border eronder intact. */
    box-shadow: inset 0 0 0 2px var(--sk-gold-border);
}

/* Hint-cel: oranje accent zolang de hint-modal open is (of vlak erna tot
   de speler een move doet). Iets sterker dan --selected zodat de speler
   snel ziet waar de uitleg over gaat. */
.sk-cell--hint {
    background: #ffd9a8 !important;
    box-shadow: inset 0 0 0 2px #d18a2c;
    animation: sk-hint-pulse 1.2s ease-in-out 1;
}
@keyframes sk-hint-pulse {
    0%   { box-shadow: inset 0 0 0 2px #d18a2c; }
    50%  { box-shadow: inset 0 0 0 3px #d18a2c, 0 0 8px rgba(209,138,44,0.4); }
    100% { box-shadow: inset 0 0 0 2px #d18a2c; }
}

/* Notes (pencil marks) */
.sk-cell--notes {
    color: var(--sk-note-color);
    font-weight: 400;
}
.sk-notes {
    display: grid;
    width: 100%;
    height: 100%;
    padding: 2px;
    box-sizing: border-box;
    gap: 0;
}
.sk-note {
    font-size: 0.32em;
    line-height: 1;
    color: var(--sk-note-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ---------- numpad ---------- */

.sudoku-numpad {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 6px;
    max-width: 540px;
    margin: 0 auto 16px;
    padding: 0 4px;
}

.sudoku-page .sk-numpad__btn {
    /* Override global button{padding:10px 15px !important; border-radius:5px !important} */
    padding: 14px 0 !important;
    border-radius: 6px !important;
    background-color: var(--sk-btn-bg) !important;
    border: 1px solid var(--sk-btn-border);
    color: #222;
    font-size: 18px;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    -webkit-tap-highlight-color: rgba(0,0,0,0.05);
    transition: background-color 0.1s, transform 0.05s;
}
.sudoku-page .sk-numpad__btn:hover {
    border-color: var(--sk-gold-border);
    background-color: var(--sk-gold-bg) !important;
}
.sudoku-page .sk-numpad__btn:active {
    transform: scale(0.96);
}
.sudoku-page .sk-numpad__btn--complete {
    color: #999;
    text-decoration: line-through;
    background-color: #f1f1ee !important;
}
.sudoku-page .sk-numpad__btn--erase {
    background-color: #f5f5f0 !important;
    color: #666;
}

/* ---------- toggle buttons (size/difficulty) ---------- */

.sudoku-page .sk-toggle {
    padding: 8px 14px !important;
    border-radius: 6px !important;
    background-color: var(--sk-btn-bg) !important;
    border: 1px solid var(--sk-btn-border);
    color: var(--sk-btn-text);
    font-size: 14px;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.1s ease;
}
.sudoku-page .sk-toggle:hover:not(:disabled) {
    border-color: var(--sk-gold-border);
}
.sudoku-page .sk-toggle.sk-toggle--active {
    background-color: var(--sk-btn-active-bg) !important;
    border-color: var(--sk-btn-active-border);
    color: var(--sk-btn-active-text);
}
.sudoku-page .sk-toggle:disabled,
.sudoku-page .sk-toggle.sk-toggle--disabled {
    opacity: var(--sk-btn-disabled-opacity);
    cursor: not-allowed;
}

/* ---------- action buttons (new, hint, undo, …) ---------- */

.sudoku-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
    max-width: 540px;
    margin: 0 auto 16px;
}

.sudoku-page .sk-btn {
    padding: 10px 16px !important;
    border-radius: 6px !important;
    background-color: var(--sk-btn-bg) !important;
    border: 1px solid var(--sk-btn-border);
    color: var(--sk-btn-text);
    font-size: 14px;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: all 0.1s ease;
}
.sudoku-page .sk-btn:hover:not(:disabled) {
    border-color: var(--sk-gold-border);
    background-color: #fcf9ed !important;
}
.sudoku-page .sk-btn:disabled {
    opacity: var(--sk-btn-disabled-opacity);
    cursor: not-allowed;
}
.sudoku-page .sk-btn--primary {
    background-color: var(--sk-gold-bg) !important;
    border-color: var(--sk-gold-border);
    color: var(--sk-gold-text);
    font-weight: 600;
}
.sudoku-page .sk-btn--on {
    background-color: var(--sk-gold-bg) !important;
    border-color: var(--sk-gold-border);
    color: var(--sk-gold-text);
}

/* ---------- download buttons ---------- */

/* Wrapper voor de download-sectie: bevat de title-header + de buttons-rij.
   De border-top zit op de wrapper (was eerder op .sudoku-downloads), zodat de
   visuele separator boven de title staat in plaats van tussen title en buttons. */
.sudoku-downloads-section {
    max-width: 540px;
    margin: 0 auto 24px;
    padding-top: 12px;
    border-top: 1px solid #ececea;
}
.sudoku-downloads-title {
    text-align: center;
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #666;
    margin-bottom: 10px;
}
.sudoku-downloads {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: center;
}
.sudoku-downloads .sk-btn {
    min-width: 100px;
}

/* ---------- flash status ---------- */

.sk-flash {
    max-width: 540px;
    margin: 0 auto 12px;
    padding: 0 16px;
    text-align: center;
    color: var(--sk-gold-text);
    background: var(--sk-gold-bg);
    border: 1px solid var(--sk-gold-border);
    border-radius: 6px;
    font-size: 14px;
    line-height: 1.4;
    opacity: 0;
    max-height: 0;
    overflow: hidden;
    transition: opacity 0.2s ease, max-height 0.2s ease, padding 0.2s ease;
}
.sk-flash.sk-flash--show {
    opacity: 1;
    max-height: 80px;
    padding: 8px 16px;
}

/* ---------- modal ---------- */

.sk-modal {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.45);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    padding: 16px;
}
.sk-modal.sk-modal--open {
    display: flex;
}
.sk-modal__inner {
    background: #fff;
    border-radius: 10px;
    padding: 28px 24px;
    max-width: 380px;
    width: 100%;
    box-shadow: 0 12px 40px rgba(0,0,0,0.25);
    text-align: center;
}
.sk-modal__title {
    font-size: 20px;
    font-weight: 600;
    color: var(--sk-gold-text);
    margin: 0 0 12px;
}
.sk-modal__body {
    font-size: 15px;
    color: #444;
    line-height: 1.5;
    margin: 0 0 20px;
}

/* Hint-modal specifieke onderdelen — links uitgelijnd ipv center voor
   leesbare uitleg-paragrafen */
.sk-modal__inner--hint {
    max-width: 460px;
    text-align: left;
}
.sk-modal__inner--hint .sk-modal__title {
    text-align: center;
}
.sk-modal__concrete {
    font-size: 16px;
    color: #222;
    font-weight: 500;
    margin: 0 0 14px;
    padding: 10px 14px;
    background: #fff8e7;
    border-radius: 6px;
    border-left: 3px solid var(--sk-gold-border, #d4a93c);
}
.sk-modal__reason {
    font-size: 14px;
    color: #555;
    line-height: 1.55;
    margin: 0 0 12px;
}
.sk-modal__link {
    font-size: 13px;
    margin: 0 0 16px;
}
.sk-modal__link a {
    color: var(--sk-gold-text, #80600F);
    text-decoration: underline;
}
.sk-modal__link a:hover {
    text-decoration: none;
}
.sk-modal__actions {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-top: 8px;
}

/* ---------- responsive ---------- */

@media (max-width: 600px) {
    .sudoku-page { padding: 0 12px; }
    .sudoku-page__header {
        padding: 18px 18px;
        border-radius: 10px;
        margin-bottom: 22px;
    }
    .sudoku-page__header:has(.sudoku-page__icon) {
        flex-direction: column;
        gap: 12px;
    }
    .sudoku-page__icon { width: 44px; height: 44px; padding: 6px; }
    .sudoku-page__title { font-size: 23px; margin-bottom: 8px; }
    .sudoku-page__intro { font-size: 15px; }
    .sudoku-page__detail { font-size: 13.5px; }
    .sudoku-toolbar { gap: 12px; }
    .sudoku-toolbar__group { width: 100%; align-items: center; }
    .sudoku-status { font-size: 13px; gap: 10px 18px; }
    .sudoku-actions { gap: 6px; }
    .sudoku-page .sk-btn { padding: 9px 12px !important; font-size: 13px; }
    .sudoku-numpad { gap: 5px; }
    .sudoku-page .sk-numpad__btn { font-size: 17px; padding: 12px 0 !important; }
    .sk-grid--9 { font-size: clamp(14px, 5vw, 22px); }
}

/* On very small screens, drop the same-digit highlight a bit to keep legibility */
@media (max-width: 380px) {
    .sk-cell--same-digit { background: #fff1c4; }
}

/* Print: keep the puzzle readable, drop chrome */
@media print {
    .sudoku-toolbar,
    .sudoku-status,
    .sudoku-numpad,
    .sudoku-actions,
    .sudoku-downloads,
    .sk-flash,
    .sudoku-tabs,
    .sudoku-solver-status,
    .sudoku-explanation,
    .sudoku-howto {
        display: none !important;
    }
    /* Hero-card chrome wegnemen in print — alleen kale tekst over */
    .sudoku-page__header {
        background: transparent !important;
        border: 0 !important;
        padding: 0 !important;
        margin-bottom: 12px !important;
        display: block !important;
    }
    .sudoku-page__icon { display: none !important; }
    .sk-cell--selected,
    .sk-cell--peer,
    .sk-cell--same-digit,
    .sk-cell--last-step {
        background: #fff !important;
        outline: none !important;
    }
    .sk-cell--given { background: #f5f5f0 !important; }
}

/* ==================== SOLVER-SPECIFIC ==================== */

/* Cells placed by the solver (not by the user). Shown in green-tinted
   regular weight; clearly distinct from user-entered bold dark digits. */
.sk-cell--solved {
    color: var(--sk-text-user);
    font-weight: 500;
    background: #f6fbf4;
}

/* Last-placed step gets a pulsing outline so the user can see what just
   happened when they click "Next step". */
.sk-cell--last-step {
    outline: 2px solid #4a7;
    outline-offset: -2px;
    background: #e8f5e3 !important;
    animation: sk-last-step-pulse 0.8s ease-out;
}
@keyframes sk-last-step-pulse {
    0%   { background: #c0e5b8 !important; }
    100% { background: #e8f5e3 !important; }
}

.sudoku-solver-status {
    max-width: 540px;
    margin: 0 auto 14px;
    padding: 10px 16px;
    text-align: center;
    background: #f4f4ef;
    border: 1px solid #e3e3dd;
    border-radius: 6px;
    font-size: 14px;
    color: #444;
    line-height: 1.4;
    font-variant-numeric: tabular-nums;
}
.sudoku-solver-status--ok {
    background: #e8f5e3;
    border-color: #b9d8ad;
    color: #2c5a18;
    font-weight: 500;
}
.sudoku-solver-status--warn {
    background: #fff3d6;
    border-color: #f1d78c;
    color: #7a5a14;
}
.sudoku-solver-status--error {
    background: #ffe2e0;
    border-color: #e8a8a3;
    color: #8a261c;
}

/* Step explanation panel — appears below the action buttons after the
   first "Next step" click. */
.sudoku-explanation {
    max-width: 540px;
    margin: 0 auto 20px;
    padding: 0 16px;
    opacity: 0;
    max-height: 0;
    overflow: hidden;
    transition: opacity 0.2s, max-height 0.2s, padding 0.2s, margin 0.2s;
}
.sudoku-explanation--visible {
    opacity: 1;
    max-height: 300px;
    padding: 14px 18px;
    margin: 4px auto 24px;
    background: #f7f4e7;
    border: 1px solid var(--sk-gold-border);
    border-radius: 8px;
}
.sudoku-explanation__head {
    margin-bottom: 6px;
    font-size: 13px;
}
.sudoku-explanation__step {
    color: #888;
    font-weight: 500;
}
.sudoku-explanation__tech {
    color: var(--sk-gold-text);
    font-weight: 600;
    font-size: 15px;
    margin-left: 4px;
}
.sudoku-explanation__body {
    color: #333;
    line-height: 1.55;
    font-size: 14px;
}

/* HowTo / techniques SEO section under the solver UI. */
.sudoku-howto {
    max-width: 720px;
    margin: 40px auto 24px;
    padding: 24px 8px 0;
    border-top: 1px solid #e3e3dd;
}
.sudoku-howto__title {
    font-size: 1.4rem;
    margin: 0 0 10px;
    color: #222;
}
.sudoku-howto__intro {
    color: #555;
    line-height: 1.5;
    margin: 0 0 18px;
}
.sudoku-howto__list {
    margin: 0;
    padding: 0;
}
.sudoku-howto__item {
    margin: 0 0 14px;
    padding: 12px 14px;
    background: #fafaf7;
    border: 1px solid #ececea;
    border-radius: 6px;
}
.sudoku-howto__term {
    font-weight: 600;
    color: var(--sk-gold-text);
    margin: 0 0 4px;
    font-size: 15px;
}
.sudoku-howto__desc {
    margin: 0;
    color: #444;
    line-height: 1.55;
    font-size: 14px;
}

/* Klikbare tab-variant (anker-element). Wordt gebruikt voor cross-page
   navigatie tussen generator ↔ oplosser. Hogere specificiteit met "a."
   om eventuele globale a:link-resets uit style1.css te overriden.
   Op rust: secondary-button uitstraling (lichtgrijs met border).
   Op hover/focus: gouden styling — identiek aan de actieve tab,
   zodat de user-affordance overeenkomt met het doel-resultaat. */
a.sudoku-tab {
    display: inline-block;
    text-decoration: none;
    color: #444;
    background: #f1f1ee;
    border: 1px solid #d8d8d4;
    padding: 7px 15px;
    cursor: pointer;
    transition: background 0.15s, border-color 0.15s, color 0.15s;
}
a.sudoku-tab:hover,
a.sudoku-tab:focus-visible {
    background: var(--sk-gold-bg);
    color: var(--sk-gold-text);
    border-color: var(--sk-gold-border);
    outline: none;
}

/* ==================== KIDS-SPECIFIC ==================== */

/* Wat verandert voor kids:
   - Grotere cellen + grotere symbool-rendering (emoji's moeten goed
     leesbaar zijn voor jonge ogen, ook op tablet/phone)
   - Geen "peer/same-digit" highlights (te druk voor doelgroep)
   - Set-selector als emoji-pillen
   - Conflict-cellen subtieler: licht-rode achtergrond i.p.v. tekst-rood
     (emoji negeert color: red, dus we tonen het via background) */

.sk-grid--kids.sk-grid--4 { max-width: 380px; }
.sk-grid--kids.sk-grid--6 { max-width: 480px; }

.sk-cell--kids {
    line-height: 1;
}
.sk-grid--kids.sk-grid--4 .sk-cell--kids {
    font-size: clamp(34px, 8vw, 56px);
}
.sk-grid--kids.sk-grid--6 .sk-cell--kids {
    font-size: clamp(26px, 6vw, 42px);
}
.sk-cell--kids.sk-cell--given {
    background: #f3f3ef;
}
.sk-cell--kids.sk-cell--conflict {
    background: #ffd6d2 !important;
}
.sk-cell--kids.sk-cell--user {
    background: #f6fbf4;
}
.sk-cell--kids.sk-cell--selected {
    background: var(--sk-cell-bg-selected);
}

/* Set-selector: 5 pill-buttons, elk met een rij emoji's */
.sudoku-kids-sets {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
    margin: 0 auto 20px;
    max-width: 720px;
}
.sk-set-btn {
    padding: 8px 14px;
    font-size: 22px;
    line-height: 1.1;
    letter-spacing: 2px;
    background: #ffffff;
    border: 2px solid var(--sk-btn-border);
    border-radius: 10px;
    cursor: pointer;
    transition: background 0.12s, border-color 0.12s, transform 0.08s;
}
.sk-set-btn:hover {
    border-color: var(--sk-gold-border);
    background: #fffaee;
}
.sk-set-btn:active {
    transform: scale(0.97);
}
.sk-set-btn--active {
    background: var(--sk-gold-bg);
    border-color: var(--sk-gold-border);
}

/* Numpad buttons groter voor emoji's */
.sudoku-page .sk-numpad__btn--kids {
    font-size: 28px;
    line-height: 1;
    padding: 14px 0 !important;
    min-width: 56px;
}
.sudoku-page .sk-numpad__btn--kids.sk-numpad__btn--erase {
    font-size: 18px;
    padding: 14px 12px !important;
}
/* Kids numpad: a "complete" symbol (all N placed) is shown by DIMMING, not a
   line-through. A strikethrough over a picture/emoji reads as "broken" rather
   than "done" (e.g. a line across the rabbit's face). The generator keeps the
   line-through for digits — there it reads correctly. Higher specificity
   (0,3,0) than the generic .sk-numpad__btn--complete (0,2,0) so it overrides. */
.sudoku-page .sk-numpad__btn--kids.sk-numpad__btn--complete {
    text-decoration: none;
    opacity: 0.4;
}

/* Toolbar group voor kids: emoji-set selector heeft eigen label-position */
.sudoku-kids-toolbar {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 18px;
    margin-bottom: 18px;
}
.sudoku-kids-toolbar__label {
    font-size: 11px;
    font-weight: 600;
    color: #777;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    text-align: center;
    margin: 0 0 6px;
}
.sudoku-kids-toolbar__row {
    display: flex;
    align-items: flex-start;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px 24px;
}

/* Mobile kids — set-buttons kleinere font, hele rij wrap */
@media (max-width: 600px) {
    .sk-set-btn { font-size: 18px; padding: 6px 10px; letter-spacing: 1px; }
    .sudoku-page .sk-numpad__btn--kids { font-size: 24px; padding: 12px 0 !important; min-width: 48px; }
    .sk-grid--kids.sk-grid--4 .sk-cell--kids { font-size: clamp(28px, 9vw, 42px); }
    .sk-grid--kids.sk-grid--6 .sk-cell--kids { font-size: clamp(22px, 7vw, 34px); }
}

/* ==================== KIDS — NUMBERS MODE ==================== */
/* When mode=numbers: render digits 1..N in cells/numpad instead of emoji.
   Cell-size en numpad-size blijven gelijk (overerving van .sk-cell--kids),
   alleen font-family + weight wisselt naar Arial-bold zodat digits visueel
   even prominent zijn als emoji. De symbol-set toolbar wordt verborgen
   (geen relevantie als de speler met cijfers werkt). */
.sk-grid--mode-numbers .sk-cell--kids {
    font-family: Arial, Helvetica, sans-serif;
    font-weight: 700;
}
.sudoku-page .sk-numpad__btn--kids.sk-numpad__btn--numbers {
    font-family: Arial, Helvetica, sans-serif;
    font-weight: 700;
}
.sudoku-kids-toolbar--hidden {
    display: none !important;
}

/* ==================== LIVE DUPLICATE CHECKBOX ==================== */
/* Persistente preference: toon duplicaten direct rood. Default AAN, speler kan
   uitzetten voor pure ervaring. Custom-styled checkbox met witte achtergrond
   en donker vinkje (in plaats van de browser-default accent-color), zodat
   het neutraal in het ontwerp valt. Twee positie-varianten:
   - default (.sudoku-options): rechts uitgelijnd onder een toolbar
   - .sudoku-options--centered: gecentreerd (kids: onder knoppen, gen: boven downloads) */
.sudoku-options {
    margin: 8px 4px 12px;
    text-align: right;
    font-size: 13px;
    color: #555;
}
.sudoku-options--centered {
    text-align: center;
    margin: 14px 0 10px;
}
.sk-checkbox {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    user-select: none;
    padding: 4px 8px;
    border-radius: 4px;
    transition: background-color 0.15s ease;
}
.sk-checkbox:hover {
    background-color: rgba(0, 0, 0, 0.04);
}
/* Witte custom checkbox — geen browser accent-color (anders krijgt hij een
   gele/groene tint). Eigen rendering: witte vierkant met donker vinkje als
   aangevinkt. */
.sk-checkbox input[type="checkbox"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    background: #ffffff;
    border: 1.5px solid #888;
    border-radius: 3px;
    cursor: pointer;
    margin: 0;
    position: relative;
    flex-shrink: 0;
    transition: border-color 0.15s ease;
}
.sk-checkbox input[type="checkbox"]:hover {
    border-color: #555;
}
.sk-checkbox input[type="checkbox"]:checked {
    background: #ffffff;
    border-color: #444;
}
.sk-checkbox input[type="checkbox"]:checked::after {
    content: '';
    position: absolute;
    left: 4px;
    top: 0px;
    width: 5px;
    height: 10px;
    border: solid #333;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}
.sk-checkbox input[type="checkbox"]:focus-visible {
    outline: 2px solid #888;
    outline-offset: 1px;
}
.sk-checkbox span {
    user-select: none;
}

@media (max-width: 600px) {
    .sudoku-options { font-size: 12px; margin: 6px 2px 10px; }
    .sudoku-options--centered { margin: 12px 0 8px; }
}

/* ==================== EXPLAIN SECTION (generator-pagina onderaan) ==================== */
/* "Hoe werkt sudoku?" — beknopte uitleg + tips voor nieuwe bezoekers.
   2-koloms grid op desktop (regels | tips), 1-koloms op mobile. Modern,
   rustig, met dezelfde gold-accent als de solver-howto sectie. */

.sudoku-explain {
    max-width: 720px;
    margin: 40px auto 24px;
    padding: 24px 8px 0;
    border-top: 1px solid #e3e3dd;
}
.sudoku-explain__title {
    font-size: 1.4rem;
    margin: 0 0 12px;
    color: #222;
}
.sudoku-explain__intro {
    color: #555;
    line-height: 1.55;
    margin: 0 0 22px;
}
.sudoku-explain__grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}
.sudoku-explain__card {
    padding: 18px 22px 14px;
    background: #fafaf7;
    border: 1px solid #ececea;
    border-radius: 8px;
}
.sudoku-explain__card-title {
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--sk-gold-text);
    margin: 0 0 12px;
    text-transform: uppercase;
    letter-spacing: 0.4px;
}
.sudoku-explain__list {
    margin: 0;
    padding-left: 22px;
    color: #444;
    line-height: 1.55;
    font-size: 14px;
}
.sudoku-explain__list li {
    margin: 0 0 8px;
}
.sudoku-explain__list li:last-child {
    margin-bottom: 0;
}
.sudoku-explain__list li::marker {
    color: var(--sk-gold-text);
    font-weight: 600;
}

@media (max-width: 600px) {
    .sudoku-explain__grid { grid-template-columns: 1fr; }
    .sudoku-explain { padding: 20px 4px 0; margin: 30px auto 16px; }
}