/* -------------------------------------------------------------------------- */
/* Design tokens — logo palette (chocolate blocks + polished gold)             */
/* -------------------------------------------------------------------------- */
:root {
    /* Extracted from `assets/img/logo.png` (dominant + highlights/shadows) */
    --color-block-deep: #201000;
    --color-block-mid: #402818;
    --color-block-edge: #604830;
    --color-bg-body: #181000;
    --color-board-inner: #302010;
    --color-board-surface: #201000;
    --color-gold-highlight: #fff135;
    --color-gold-face: #f8c840;
    --color-gold-mid: #f0b028;
    --color-gold-shadow: #e09818;
    --color-gold-edge: #271100;
    --color-amber-muted: rgba(248, 200, 64, 0.72);
    --color-text: #ffffff;
    --color-neutral-300: #e7e5e4;
    --font-serif: "Lora", serif;
    --font-display: "Cinzel", serif;
    --font-ui: "Montserrat", system-ui, sans-serif;
    --radius-board: 12px;
    --radius-block: 6px;
    --radius-btn: 0.375rem;
    --shadow-board: 0 22px 52px rgba(0, 0, 0, 0.78);
    --z-board-ui: 10;
    --z-block-main: 20;
    --z-block-drag: 30;
    --z-overlay: 50;
    --transition-overlay: opacity 0.3s ease;
    --transition-card: transform 0.5s ease;
    --block-left: 0px;
    --block-top: 0px;
    --block-w: 0px;
    --block-h: 0px;
    /* Must match CONFIG.GRID_SIZE in assets/js/script.js */
    --grid-size: 6;
    --app-bg-image: url("../img/bg.png");
}

/* -------------------------------------------------------------------------- */
/* Base                                                                       */
/* -------------------------------------------------------------------------- */
*,
*::before,
*::after {
    box-sizing: border-box;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

html,
body {
    margin: 0;
    height: 100%;
}

body.app {
    font-family: var(--font-serif);
    color: var(--color-text);
    background-color: var(--color-bg-body);
    background-image: var(--app-bg-image);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    overscroll-behavior: none;
    touch-action: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    min-height: 100vh;
    width: 100%;
}

/* -------------------------------------------------------------------------- */
/* Topbar                                                                     */
/* -------------------------------------------------------------------------- */
.topbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 0.75rem 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    z-index: var(--z-board-ui);
    pointer-events: none;
}

.topbar > * {
    pointer-events: auto;
}

.topbar__left {
    display: inline-flex;
    align-items: center;
    gap: 0.65rem;
}

.topbar__btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.4rem;
    height: 2.4rem;
    padding: 0;
    background: linear-gradient(145deg, var(--color-block-mid) 0%, var(--color-block-deep) 100%);
    border: 1px solid var(--color-gold-shadow);
    border-radius: 50%;
    color: var(--color-gold-face);
    cursor: pointer;
    box-shadow: inset 2px 2px 4px rgba(74, 55, 40, 0.35), inset -2px -2px 6px rgba(0, 0, 0, 0.45),
        0 6px 14px rgba(0, 0, 0, 0.45);
    transition: color 0.15s ease, background-color 0.15s ease, border-color 0.15s ease,
        transform 0.1s ease, opacity 0.15s ease;
}

.topbar__btn:hover:not(:disabled) {
    color: #fffef0;
    background: linear-gradient(145deg, var(--color-block-edge) 0%, var(--color-block-mid) 100%);
    border-color: var(--color-gold-mid);
}

.topbar__btn:active:not(:disabled) {
    transform: scale(0.94);
}

.topbar__btn:disabled {
    opacity: 0.55;
    cursor: not-allowed;
}

.topbar__btn-icon {
    width: 1.25rem;
    height: 1.25rem;
    flex-shrink: 0;
}

.topbar__btn.is-busy .topbar__btn-icon {
    animation: pulse-opacity 1s ease-in-out infinite;
}

.topbar__level {
    font-family: var(--font-ui);
    font-weight: 700;
    font-size: 0.82rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--color-amber-muted);
    white-space: nowrap;
    text-shadow: 0 1px 3px rgba(0, 0, 0, 0.75);
}

.topbar__level-num {
    font-family: var(--font-display);
    font-weight: 800;
    color: var(--color-gold-face);
    margin-left: 0.35rem;
    letter-spacing: 0.04em;
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.35), 0 2px 4px rgba(0, 0, 0, 0.8);
}

.topbar__actions {
    display: flex;
    gap: 0.5rem;
}

/* -------------------------------------------------------------------------- */
/* Game shell — thick frame + thin gold inner rim (logo board)                 */
/* -------------------------------------------------------------------------- */
.game-shell {
    position: relative;
    width: 100%;
    max-width: min(90vw, 28rem);
    aspect-ratio: 1;
    z-index: var(--z-board-ui);
}

.game-shell__wrapper {
    width: 100%;
    height: 100%;
    position: relative;
    padding: 8px;
    border-radius: var(--radius-board);
    background: linear-gradient(160deg, var(--color-block-edge) 0%, var(--color-board-inner) 52%, var(--color-block-deep) 100%);
    border: 1px solid #1f1512;
    box-shadow: var(--shadow-board), inset 0 1px 0 rgba(255, 215, 0, 0.42),
        inset 0 0 0 1px rgba(139, 101, 8, 0.55);
}

.game-shell__wrapper::after {
    content: "";
    position: absolute;
    inset: 8px;
    border-radius: calc(var(--radius-board) - 6px);
    pointer-events: none;
    /* Subtle ambient spotlight so the board doesn't read black */
    background: radial-gradient(120% 110% at 50% 22%, rgba(255, 241, 53, 0.10) 0%, rgba(255, 241, 53, 0.04) 28%, rgba(0, 0, 0, 0) 62%),
        radial-gradient(140% 120% at 50% 60%, rgba(255, 255, 255, 0.05) 0%, rgba(0, 0, 0, 0) 55%);
    mix-blend-mode: screen;
    opacity: 0.9;
}

#game-board {
    width: 100%;
    height: 100%;
    position: relative;
    touch-action: none;
    background-color: var(--color-board-surface);
    background-image:
        radial-gradient(140% 120% at 50% 18%, rgba(255, 241, 53, 0.11) 0%, rgba(255, 241, 53, 0.03) 34%, rgba(0, 0, 0, 0) 62%),
        linear-gradient(160deg, rgba(0, 0, 0, 0.22) 0%, rgba(0, 0, 0, 0) 38%, rgba(0, 0, 0, 0.30) 100%),
        linear-gradient(rgba(0, 0, 0, 0.20) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 0, 0, 0.20) 1px, transparent 1px);
    background-size: calc(100% / var(--grid-size)) calc(100% / var(--grid-size));
    border-radius: calc(var(--radius-board) - 6px);
}

/* Exit slot — dark channel + gold arrow (logo exit notch)                     */
.exit-slot {
    position: absolute;
    right: -14px;
    top: calc(100% / var(--grid-size) * 2);
    height: calc(100% / var(--grid-size));
    width: 20px;
    background: linear-gradient(to right, var(--color-block-deep), #000000);
    box-shadow: inset 4px 0 12px rgba(0, 0, 0, 0.85);
    z-index: var(--z-board-ui);
    border-radius: 0 2px 2px 0;
}

.exit-slot::after {
    content: "►";
    position: absolute;
    right: -22px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-gold-face);
    font-size: 18px;
    text-shadow: 0 0 12px rgba(255, 215, 0, 0.85), 0 2px 4px rgba(0, 0, 0, 0.9);
    animation: pulse-arrow 2s infinite;
}

@keyframes pulse-arrow {
    0%,
    100% {
        opacity: 0.45;
        transform: translate(0, -50%);
    }
    50% {
        opacity: 1;
        transform: translate(4px, -50%);
    }
}

/* Blocks — top-left light (logo lighting)                                    */
.block {
    position: absolute;
    left: var(--block-left);
    top: var(--block-top);
    width: var(--block-w);
    height: var(--block-h);
    border-radius: var(--radius-block);
    transition: transform 0.1s ease-out;
    cursor: grab;
    user-select: none;
    overflow: hidden;
    transform: translateZ(0);
    box-shadow:
        inset 3px 3px 9px rgba(255, 255, 255, 0.14),
        inset -5px -5px 12px rgba(0, 0, 0, 0.58),
        0 8px 14px rgba(0, 0, 0, 0.52);
}

.block::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    pointer-events: none;
    /* Bevel highlight (top-left) + edge rim */
    background:
        linear-gradient(145deg, rgba(255, 255, 255, 0.22) 0%, rgba(255, 255, 255, 0.06) 32%, rgba(0, 0, 0, 0.12) 72%, rgba(0, 0, 0, 0.28) 100%),
        radial-gradient(140% 120% at 18% 18%, rgba(255, 255, 255, 0.18) 0%, rgba(255, 255, 255, 0.06) 35%, rgba(0, 0, 0, 0) 60%),
        radial-gradient(140% 120% at 82% 86%, rgba(0, 0, 0, 0) 45%, rgba(0, 0, 0, 0.32) 100%);
    opacity: 1;
    mix-blend-mode: overlay;
}

.block::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    pointer-events: none;
    /* Surface micro-texture + soft vignette */
    background:
        repeating-linear-gradient(
            135deg,
            rgba(255, 255, 255, 0.025) 0px,
            rgba(255, 255, 255, 0.025) 1px,
            rgba(0, 0, 0, 0.03) 2px,
            rgba(0, 0, 0, 0.03) 4px
        ),
        radial-gradient(120% 120% at 50% 45%, rgba(0, 0, 0, 0) 35%, rgba(0, 0, 0, 0.26) 100%);
    opacity: 0.34;
}

.block.is-dragging {
    z-index: var(--z-block-drag);
    transform: translateY(-2px) scale(1.01);
    box-shadow:
        inset 3px 3px 10px rgba(255, 255, 255, 0.18),
        inset -5px -5px 13px rgba(0, 0, 0, 0.6),
        0 18px 28px rgba(0, 0, 0, 0.58);
}

.block:active {
    cursor: grabbing;
}

.block.animating {
    transition: left 0.25s ease-in-out, top 0.25s ease-in-out, width 0.25s ease-in-out, height 0.25s ease-in-out;
}

.block-stone {
    background:
        radial-gradient(120% 120% at 22% 18%, rgba(255, 255, 255, 0.16) 0%, rgba(255, 255, 255, 0.06) 40%, rgba(0, 0, 0, 0) 62%),
        radial-gradient(120% 120% at 44% 34%, rgba(240, 176, 40, 0.22) 0%, rgba(240, 176, 40, 0.08) 46%, rgba(0, 0, 0, 0) 74%),
        linear-gradient(145deg, #8a6436 0%, #705030 34%, #604028 100%);
    border: none;
    box-shadow:
        inset 4px 4px 12px rgba(255, 255, 255, 0.11),
        inset -5px -5px 14px rgba(0, 0, 0, 0.55),
        0 8px 14px rgba(0, 0, 0, 0.50),
        0 0 0 1px rgba(0, 0, 0, 0.18);
}

.block-main {
    background: linear-gradient(
        145deg,
        var(--color-gold-highlight) 0%,
        var(--color-gold-face) 18%,
        var(--color-gold-mid) 45%,
        var(--color-gold-shadow) 100%
    );
    border: 1px solid var(--color-gold-edge);
    box-shadow: inset 3px 3px 10px rgba(255, 255, 255, 0.65), inset -4px -4px 12px rgba(91, 60, 8, 0.75),
        0 0 18px rgba(255, 215, 0, 0.35), 3px 4px 10px rgba(0, 0, 0, 0.55);
    z-index: var(--z-block-main);
    display: flex;
    align-items: center;
    justify-content: center;
}

.block-main .block-main__icon {
    width: 2.5rem;
    height: 2.5rem;
    color: var(--color-block-deep);
    pointer-events: none;
    opacity: 0.92;
    filter: drop-shadow(0 1px 0 rgba(255, 248, 220, 0.25));
}

.slide-out {
    transition: left 0.6s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.25s ease-out !important;
    left: 120% !important;
    opacity: 0;
}

#game-board.solving .block {
    pointer-events: none;
}

/* -------------------------------------------------------------------------- */
/* Buttons                                                                    */
/* -------------------------------------------------------------------------- */
.btn {
    font-family: var(--font-ui);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-btn);
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    cursor: pointer;
    border: 1px solid transparent;
    box-shadow: 0 10px 18px -4px rgba(0, 0, 0, 0.45);
    transition: color 0.15s ease, background-color 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}

.btn:active:not(:disabled) {
    transform: scale(0.95);
}

.btn:disabled {
    opacity: 0.65;
    cursor: not-allowed;
}

.btn--block {
    width: 100%;
}

/* -------------------------------------------------------------------------- */
/* Overlays                                                                   */
/* -------------------------------------------------------------------------- */
.overlay {
    position: fixed;
    inset: 0;
    z-index: var(--z-overlay);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    opacity: 0;
    pointer-events: none;
    transition: var(--transition-overlay);
}

.overlay--dim {
    background: rgba(0, 0, 0, 0.82);
}

.overlay--dim-soft {
    background: rgba(0, 0, 0, 0.72);
}

/* How-to overlay should be lighter than other modals */
#howto-modal {
    background: rgba(0, 0, 0, 0.38);
    backdrop-filter: blur(3px);
    -webkit-backdrop-filter: blur(3px);
}

/* Loader overlay should be lighter (keep theme visible) */
#puzzle-loader {
    background: rgba(0, 0, 0, 0.42);
    backdrop-filter: blur(3px);
    -webkit-backdrop-filter: blur(3px);
}

.overlay.is-open {
    opacity: 1;
    pointer-events: auto;
}

/* Puzzle loader */
.loader__spinner {
    width: 4rem;
    height: 4rem;
    border-radius: 9999px;
    border: 4px solid transparent;
    border-top-color: var(--color-gold-face);
    border-bottom-color: var(--color-gold-mid);
    margin-bottom: 1.5rem;
    box-shadow: 0 0 18px rgba(255, 215, 0, 0.45);
    animation: spin 0.8s linear infinite;
}

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

.loader__title {
    margin: 0;
    font-family: var(--font-display);
    font-size: 1.875rem;
    font-weight: 800;
    color: var(--color-gold-face);
    letter-spacing: 0.08em;
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.3), 0 2px 8px rgba(0, 0, 0, 0.85);
    animation: pulse-opacity 2s ease-in-out infinite;
}

@keyframes pulse-opacity {
    0%,
    100% {
        opacity: 1;
    }
    50% {
        opacity: 0.65;
    }
}

/* Win modal */
#win-modal {
    background: transparent;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
}

.win-card {
    padding: 2rem;
    text-align: center;
    transform: scale(0.9);
    transition: var(--transition-card);
}

.overlay.is-open .win-card {
    transform: scale(1);
}

.win-card__title {
    margin: 0 0 0.5rem;
    font-family: var(--font-display);
    font-size: 2.25rem;
    font-weight: 800;
    letter-spacing: 0.06em;
    color: var(--color-gold-face);
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.45), 0 3px 6px rgba(0, 0, 0, 0.85);
}

.win-card__flavor {
    margin: 0 0 2rem;
    color: var(--color-neutral-300);
    font-style: italic;
}

.btn--primary-lg {
    font-size: 1.05rem;
    padding: 0.85rem 2rem;
    font-weight: 800;
    color: #1a1008;
    background: linear-gradient(
        180deg,
        var(--color-gold-highlight) 0%,
        var(--color-gold-face) 22%,
        var(--color-gold-mid) 55%,
        var(--color-gold-shadow) 100%
    );
    border: 1px solid var(--color-gold-edge);
    text-shadow: 0 1px 0 rgba(255, 250, 220, 0.35);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.45), 0 12px 24px rgba(0, 0, 0, 0.4);
}

.btn--primary-lg:hover:not(:disabled) {
    background: linear-gradient(
        180deg,
        var(--color-gold-highlight) 0%,
        var(--color-gold-face) 22%,
        var(--color-gold-mid) 55%,
        var(--color-gold-shadow) 100%
    );
}

/* -------------------------------------------------------------------------- */
/* Start modal                                                                */
/* -------------------------------------------------------------------------- */
#start-modal {
    background-color: var(--color-bg-body);
    background-image: var(--app-bg-image);
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
}

.start-card__logo {
    display: block;
    width: min(100%, 12.5rem);
    height: auto;
    margin: 0 auto 1.25rem;
    border-radius: var(--radius-board);
    filter: drop-shadow(0 12px 28px rgba(0, 0, 0, 0.65));
}

.start-card {
    padding: 1.75rem 1.5rem 2rem;
    text-align: center;
    transform: scale(0.92);
    transition: var(--transition-card);
    width: min(92vw, 24rem);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.overlay.is-open .start-card {
    transform: scale(1);
}

.howto-card {
    width: min(92vw, 28rem);
    padding: 1.25rem 1.25rem 1.5rem;
    transform: scale(0.96);
    transition: var(--transition-card);
}

.overlay.is-open .howto-card {
    transform: scale(1);
}

/* -------------------------------------------------------------------------- */
/* Popup cards — match board frame theme                                       */
/* -------------------------------------------------------------------------- */
.win-card,
.start-card,
.howto-card {
    position: relative;
    border-radius: var(--radius-board);
    overflow: hidden;
    background: linear-gradient(
        160deg,
        var(--color-block-edge) 0%,
        var(--color-board-inner) 52%,
        var(--color-block-deep) 100%
    );
    border: 1px solid #1f1512;
    box-shadow: 0 22px 52px rgba(0, 0, 0, 0.72), inset 0 1px 0 rgba(255, 215, 0, 0.34),
        inset 0 0 0 1px rgba(139, 101, 8, 0.5);
}

.win-card::after,
.start-card::after,
.howto-card::after {
    content: "";
    position: absolute;
    inset: 10px;
    border-radius: calc(var(--radius-board) - 6px);
    pointer-events: none;
    box-shadow: inset 0 0 0 1px rgba(255, 241, 53, 0.28), inset 0 0 0 2px rgba(39, 17, 0, 0.45);
    opacity: 0.9;
}

.howto-card__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

.howto-card__title {
    margin: 0;
    font-family: var(--font-display);
    font-size: 1.65rem;
    font-weight: 800;
    letter-spacing: 0.06em;
    color: var(--color-gold-face);
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.35), 0 2px 6px rgba(0, 0, 0, 0.8);
}

.howto-card__close {
    width: 2.2rem;
    height: 2.2rem;
}

.howto-card__body {
    color: var(--color-neutral-300);
    font-family: var(--font-serif);
}

.howto-card__text {
    margin: 0 0 0.75rem;
    font-style: italic;
}

.howto-card__list {
    margin: 0;
    padding-left: 1.1rem;
    line-height: 1.45;
}

.howto-card__list li + li {
    margin-top: 0.4rem;
}

.start-card__title {
    margin: 0 0 0.25rem;
    font-family: var(--font-display);
    font-size: 2.25rem;
    font-weight: 800;
    letter-spacing: 0.1em;
    color: var(--color-gold-mid);
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.35), 0 2px 6px rgba(0, 0, 0, 0.75);
}

.start-card__level-card {
    width: 7rem;
    height: 7rem;
    align-self: center;
    background: linear-gradient(145deg, var(--color-block-edge) 0%, var(--color-block-deep) 100%);
    border: 1px solid var(--color-gold-shadow);
    border-radius: var(--radius-block);
    margin-bottom: 1.75rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.25rem;
    box-shadow: inset 3px 3px 8px rgba(74, 55, 40, 0.35), inset -2px -2px 10px rgba(0, 0, 0, 0.55),
        0 4px 12px rgba(0, 0, 0, 0.4);
}

.start-card__level-label {
    font-family: var(--font-ui);
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.28em;
    text-transform: uppercase;
    color: var(--color-amber-muted);
}

.start-card__level-num {
    font-family: var(--font-display);
    font-weight: 800;
    font-size: 2.75rem;
    line-height: 1;
    color: var(--color-gold-face);
    text-shadow: 0 1px 0 rgba(255, 248, 220, 0.4), 0 0 18px rgba(255, 215, 0, 0.45);
}

/* -------------------------------------------------------------------------- */
/* Responsive layout — comprehensive breakpoints                               */
/* -------------------------------------------------------------------------- */

/* Small Mobile (≤480px) */
@media (max-width: 480px) {
    .topbar {
        padding: 0.55rem 0.65rem;
        gap: 0.5rem;
    }

    .topbar__actions {
        gap: 0.4rem;
    }

    .topbar__btn {
        width: 2.1rem;
        height: 2.1rem;
    }

    .topbar__btn-icon {
        width: 1.1rem;
        height: 1.1rem;
    }

    .topbar__level {
        font-size: 0.72rem;
        letter-spacing: 0.12em;
    }

    .game-shell {
        max-width: min(94vw, 22.5rem);
    }

    .game-shell__wrapper {
        padding: 6px;
    }

    .game-shell__wrapper::after {
        inset: 6px;
    }

    .exit-slot {
        right: -12px;
        width: 18px;
    }

    .exit-slot::after {
        right: -20px;
        font-size: 16px;
    }

    .win-card {
        padding: 1.4rem 1.25rem 1.6rem;
        width: min(92vw, 24rem);
    }

    .win-card__title {
        font-size: 1.75rem;
    }

    .win-card__flavor {
        margin-bottom: 1.4rem;
        font-size: 0.98rem;
    }

    .start-card {
        padding: 1.35rem 1.15rem 1.5rem;
        width: min(92vw, 22.5rem);
    }

    .start-card__logo {
        width: min(100%, 10.5rem);
        margin-bottom: 1rem;
    }

    .start-card__level-card {
        width: 6.25rem;
        height: 6.25rem;
        margin-bottom: 1.2rem;
    }

    .start-card__level-num {
        font-size: 2.4rem;
    }

    .howto-card {
        width: min(94vw, 26rem);
        padding: 1.05rem 1.05rem 1.25rem;
    }

    .howto-card__title {
        font-size: 1.35rem;
    }

    .howto-card__body {
        font-size: 0.98rem;
    }

    .howto-card__body,
    .win-card,
    .start-card {
        max-height: 86vh;
        overflow: auto;
    }

    .btn--primary-lg {
        font-size: 1rem;
        padding: 0.78rem 1.6rem;
    }

    .loader__spinner {
        width: 3.2rem;
        height: 3.2rem;
        margin-bottom: 1.15rem;
    }

    .loader__title {
        font-size: 1.45rem;
        letter-spacing: 0.06em;
        text-align: center;
        padding: 0 1rem;
    }
}

/* Mobile (≤640px) */
@media (min-width: 481px) and (max-width: 640px) {
    .topbar {
        padding: 0.65rem 0.85rem;
    }

    .topbar__btn {
        width: 2.25rem;
        height: 2.25rem;
    }

    .game-shell {
        max-width: min(92vw, 26rem);
    }

    .win-card,
    .start-card,
    .howto-card {
        max-height: 88vh;
        overflow: auto;
    }

    .win-card__title {
        font-size: 2rem;
    }

    .howto-card__title {
        font-size: 1.5rem;
    }
}

/* Tablet Portrait (641px-768px) */
@media (min-width: 641px) and (max-width: 768px) {
    .topbar {
        padding: 0.85rem 1rem;
    }

    .topbar__btn {
        width: 2.55rem;
        height: 2.55rem;
    }

    .topbar__btn-icon {
        width: 1.3rem;
        height: 1.3rem;
    }

    .game-shell {
        max-width: min(86vw, 30rem);
    }

    .start-card {
        width: min(86vw, 26rem);
    }

    .howto-card {
        width: min(86vw, 30rem);
    }
}

/* Tablet Landscape (769px-1024px) */
@media (min-width: 769px) and (max-width: 1024px) {
    .topbar {
        padding: 1rem 1.25rem;
    }

    .topbar__btn {
        width: 2.7rem;
        height: 2.7rem;
    }

    .game-shell {
        max-width: min(78vw, 32rem);
    }

    .howto-card {
        width: min(72vw, 32rem);
    }
}

/* Desktop (≥1025px) */
@media (min-width: 1025px) {
    .game-shell {
        max-width: 36rem;
    }

    .howto-card {
        width: 34rem;
    }
}

/* Landscape Mobile (orientation: landscape) */
@media (max-height: 480px) and (orientation: landscape) {
    body.app {
        justify-content: flex-start;
    }

    .topbar {
        padding: 0.45rem 0.7rem;
    }

    .topbar__btn {
        width: 2.05rem;
        height: 2.05rem;
    }

    .game-shell {
        max-width: min(72vh, 24rem);
        margin-top: 3.2rem;
    }

    .game-shell__wrapper {
        padding: 6px;
    }

    .win-card,
    .start-card,
    .howto-card {
        max-height: 82vh;
        overflow: auto;
    }
}