.stack-app {
            --bg: var(--card-background);
            --panel: var(--card-background);
            --panel-strong: var(--card-background);
            --text: var(--card-text-color-main);
            --muted: var(--card-text-color-secondary);
            --accent: var(--accent-color);
            --accent-2: var(--accent-color);
            --danger: #ff7675;
            --border: var(--card-separator-color);
            --shadow: 0 22px 60px rgba(0, 0, 0, 0.38);
        }

        .stack-app * { box-sizing: border-box; }

        .stack-app,
.stack-app {
            background:
                var(--card-background);
            color: inherit;
            font-family: var(--base-font-family);
        }

        .stack-app::before {
            content: "";
            position: fixed;
            inset: 0;
            pointer-events: none;
            opacity: 0.12;
            background-image: none;
            background-size: 44px 44px;
            mask-image: linear-gradient(180deg, rgba(0,0,0,0.85), transparent 92%);
        }

        .stack-app a { color: inherit; text-decoration: none; }

        .stack-app .nav {
            position: sticky;
            top: 0;
            z-index: 10;
            display: flex;
            justify-content: center;
            gap: 14px;
            padding: 12px 16px;
            background: var(--card-background);
            backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--card-separator-color);
        }

        .stack-app .nav a {
            padding: 8px 14px;
            border: 1px solid var(--card-separator-color);
            border-radius: 999px;
            color: inherit;
            font-weight: 600;
            transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
            background: var(--card-background);
        }

        .stack-app .nav a:hover {
            transform: translateY(-1px);
            border-color: var(--card-separator-color);
            background: var(--card-background);
        }

        .stack-app .nav a[aria-current="page"] {
            border-color: var(--card-separator-color);
            color: inherit;
        }

        .stack-app .nav a:focus-visible {
            outline: 3px solid var(--accent-2);
            outline-offset: 3px;
        }

        .stack-app .page {
            width: min(1180px, calc(100vw - 24px));
            margin: 0 auto;
            padding: 22px 0 28px;
        }

        .stack-app .hero {
            display: grid;
            grid-template-columns: 1.2fr 0.8fr;
            gap: 18px;
            align-items: stretch;
        }

        .stack-app .panel {
            background: var(--card-background);
            border: 1px solid var(--card-separator-color);
            box-shadow: var(--shadow-l1);
            border-radius: var(--card-border-radius);
            overflow: hidden;
            position: relative;
        }

        .stack-app .panel::after {
            content: "";
            position: absolute;
            inset: 0;
            background: var(--card-background);
            pointer-events: none;
        }

        .stack-app .intro {
            padding: 26px;
        }

        .stack-app .eyebrow {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 6px 12px;
            border-radius: 999px;
            background: var(--card-background);
            color: inherit;
            border: 1px solid var(--card-separator-color);
            font-size: 1.408rem;
            letter-spacing: 0.04em;
        }

        .stack-app h1 {
            margin: 16px 0 10px;
            font-size: clamp(3.2rem, 4vw, 5.92rem);
            line-height: 1;
        }

        .stack-app .lede {
            margin: 0;
            max-width: 58ch;
            color: inherit;
            line-height: 1.75;
        }

        .stack-app .stats {
            margin-top: 20px;
            display: grid;
            grid-template-columns: repeat(3, minmax(0, 1fr));
            gap: 12px;
        }

        .stack-app .stat {
            padding: 14px 16px;
            border-radius: var(--card-border-radius);
            background: var(--card-background);
            border: 1px solid var(--card-separator-color);
        }

        .stack-app .stat span {
            display: block;
            color: inherit;
            font-size: 1.344rem;
            margin-bottom: 6px;
        }

        .stack-app .stat strong {
            font-size: 2.16rem;
        }

        .stack-app .side {
            display: grid;
            gap: 14px;
            padding: 18px;
        }

        .stack-app .control-row {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
        }

        .stack-app button {
            appearance: none;
            border: 0;
            font-family: var(--base-font-family);
        }

        .stack-app .btn {
            padding: 12px 16px;
            border-radius: var(--card-border-radius);
            color: inherit;
            font-weight: 700;
            cursor: pointer;
            transition: transform 0.15s ease, filter 0.15s ease, opacity 0.15s ease;
            box-shadow: var(--shadow-l1);
        }

        .stack-app .btn:hover { transform: translateY(-1px); }
        .stack-app .btn:active { transform: translateY(0); }

        .stack-app .btn-primary { background: var(--card-background); color: inherit; }
        .stack-app .btn-secondary { background: var(--card-background); }
        .stack-app .btn-danger { background: var(--card-background); }

        .stack-app .setting-label {
            display: block;
            margin: 12px 0 8px;
            color: inherit;
            font-size: 1.44rem;
            font-weight: 600;
        }

        .stack-app .setting-select {
            width: 100%;
            padding: 11px 12px;
            border-radius: var(--card-border-radius);
            border: 1px solid var(--card-separator-color);
            background: var(--card-background);
            color: inherit;
            font-family: var(--base-font-family);
            outline: none;
        }

        .stack-app .setting-pill {
            min-width: 86px;
            padding: 11px 12px;
            border-radius: var(--card-border-radius);
            border: 1px solid var(--card-separator-color);
            background: var(--card-background);
            color: inherit;
            font-weight: 700;
            text-align: center;
        }

        .stack-app .ai-status-box {
            margin-top: 12px;
            padding: 12px 14px;
            border-radius: var(--card-border-radius);
            border: 1px solid var(--card-separator-color);
            background: var(--card-background);
            color: inherit;
            line-height: 1.6;
        }

        .stack-app .tip {
            padding: 14px 16px;
            border-radius: var(--card-border-radius);
            background: var(--card-background);
            border: 1px solid var(--card-separator-color);
            color: inherit;
            line-height: 1.7;
        }

        .stack-app .game-wrap {
            margin-top: 18px;
            padding: 18px;
        }

        .stack-app .game-shell {
            display: grid;
            grid-template-columns: minmax(0, 1fr) 290px;
            gap: 18px;
            align-items: start;
        }

        .stack-app .canvas-frame {
            background: var(--card-background);
            border-radius: var(--card-border-radius);
            padding: 16px;
            border: 1px solid var(--card-separator-color);
            box-shadow: var(--shadow-l1);
        }

        .stack-app .canvas-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 12px;
            margin-bottom: 12px;
            color: inherit;
            font-size: 1.472rem;
        }

        .stack-app .canvas-status {
            color: inherit;
            font-weight: 700;
        }

        .stack-app canvas {
            width: 100%;
            display: block;
            border-radius: var(--card-border-radius);
            background:
                var(--card-background);
            touch-action: none;
        }

        .stack-app .sidebar-card {
            padding: 16px;
            border-radius: var(--card-border-radius);
            background: var(--card-background);
            border: 1px solid var(--card-separator-color);
        }

        .stack-app .sidebar-card h2,
.stack-app .sidebar-card h3 {
            margin: 0 0 10px;
        }

        .stack-app .fruit-next {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .stack-app .fruit-badge {
            width: 64px;
            height: 64px;
            border-radius: 50%;
            display: grid;
            place-items: center;
            font-size: 1.2rem;
            font-weight: 800;
            color: rgba(8, 16, 27, 0.92);
            box-shadow: inset 0 4px 8px rgba(255,255,255,0.22), 0 12px 20px rgba(0,0,0,0.26);
            border: 2px solid rgba(255,255,255,0.16);
        }

        .stack-app .mini-list {
            margin: 0;
            padding-left: 18px;
            color: inherit;
            line-height: 1.8;
        }

        .stack-app .footer {
            padding: 20px 0 6px;
            text-align: center;
            color: inherit;
        }

        .stack-app .footer small { color: inherit; }

        @media (max-width: 980px) {
            .stack-app .hero,
.stack-app .game-shell { grid-template-columns: 1fr; }
            .stack-app .stats { grid-template-columns: 1fr; }
        }

        @media (max-width: 640px) {
            .stack-app .page { width: min(100vw - 16px, 1180px); padding-top: 14px; }
            .stack-app .nav { gap: 8px; padding-inline: 10px; flex-wrap: wrap; }
            .stack-app .nav a { padding: 7px 12px; }
            .stack-app .intro,
.stack-app .game-wrap { padding: 14px; }
            .stack-app .canvas-frame { padding: 12px; }
        }