:root {
            
            --background: #f8f9fa;
            --on-background: #1a1d20;
            --surface: #ffffff;
            --on-surface: #2d3135;
            --surface-variant: #eef1f6;
            --on-surface-variant: #43474e;
            --surface-container: #f0f3f8;
            --surface-container-low: #f4f6fa;
            --surface-container-high: #e8ebee;
            --surface-container-highest: #e0e3e7;
            --surface-container-lowest: #ffffff;
            --primary: #3f5f90;
            --on-primary: #ffffff;
            --primary-container: #d6e3ff;
            --on-primary-container: #001b3e;
            --secondary: #b8860b;
            --on-secondary: #ffffff;
            --secondary-container: #ffe0b2;
            --on-secondary-container: #261900;
            --outline: #73777f;
            --outline-variant: #c3c7cf;
            --surface-bright: #fcfcff;
            --surface-dim: #d8dbdf;

            --error: #ba1a1a;
            --on-error: #ffffff;
            --error-container: #ffdad6;
            --on-error-container: #410002;

            --tertiary: #575f71;
            --on-tertiary: #ffffff;
            --tertiary-container: #dbe2f9;
            --on-tertiary-container: #141c2b;

            --glass-card-bg: rgba(255, 255, 255, 0.65);
            --glass-card-border: rgba(0, 0, 0, 0.08);
            --glass-card-shadow: rgba(31, 38, 135, 0.08);
        }

        html.dark {
            
            --background: #0b0d0e;
            --on-background: #e1e3e4;
            --surface: #111415;
            --on-surface: #e1e3e4;
            --surface-variant: #222527;
            --on-surface-variant: #c5c6cd;
            --surface-container: #141718;
            --surface-container-low: #111415;
            --surface-container-high: #1d2021;
            --surface-container-highest: #282b2c;
            --surface-container-lowest: #070809;
            --primary: #b9c7e4;
            --on-primary: #111c2c;
            --primary-container: #0d1c32;
            --on-primary-container: #74829d;
            --secondary: #e9c176;
            --on-secondary: #1d2021;
            --secondary-container: #412d00;
            --on-secondary-container: #e9c176;
            --outline: #8f9097;
            --outline-variant: #2b2e30;
            --surface-bright: #2c2f30;
            --surface-dim: #0b0d0e;

            --error: #ffb4ab;
            --on-error: #690005;
            --error-container: #93000a;
            --on-error-container: #ffdad6;

            --tertiary: #bcc7dd;
            --on-tertiary: #263142;
            --tertiary-container: #0e192a;
            --on-tertiary-container: #778297;

            --glass-card-bg: rgba(29, 32, 33, 0.65);
            --glass-card-border: rgba(255, 255, 255, 0.05);
            --glass-card-shadow: rgba(0, 0, 0, 0.37);
        }

        body,
        a,
        button,
        [role="button"],
        input,
        select,
        textarea,
        .cursor-pointer {
            cursor: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='48' height='48' viewBox='0 0 100 100' fill='none'><path d='M50 8v11M45 13h10' stroke='%231c1f20' stroke-width='4' stroke-linecap='round'/><path d='M37 38 L33 22 L42 29 L50 19 L58 29 L67 22 L63 38 Z' fill='%23dab36a' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><rect x='35' y='38' width='30' height='5' rx='2.5' fill='%23dab36a' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><path d='M37 43 L35 70 h15 V43 Z' fill='%23dab36a' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><path d='M39 46 L37.5 67' stroke='%23ffffff' stroke-width='2' stroke-linecap='round' opacity='0.9'/><path d='M50 43 h15 L63 70 H50 Z' fill='%231c1f20' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><rect x='33' y='70' width='34' height='4' rx='2' fill='%23dab36a' stroke='%231c1f20' stroke-width='2' stroke-linejoin='round'/><path d='M31 74 L29 78 h21 V74 Z' fill='%23dab36a' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><path d='M50 74 h21 L69 78 H50 Z' fill='%231c1f20' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/><rect x='26' y='78' width='48' height='5' rx='1' fill='%23dab36a' stroke='%231c1f20' stroke-width='3' stroke-linejoin='round'/></svg>") 24 24, auto !important;
        }

        .material-symbols-outlined {
            font-variation-settings: 'FILL' 0, 'wght' 300, 'GRAD' 0, 'opsz' 24;
        }

        .glass-card {
            background: var(--glass-card-bg);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid var(--glass-card-border);
            box-shadow: 0 8px 32px 0 var(--glass-card-shadow);
        }

        .glow-accent {
            box-shadow: 0 0 40px rgba(233, 193, 118, 0.08);
        }

        .chess-grid-bg {
            background-image:
                linear-gradient(to right, rgba(233, 193, 118, 0.03) 1px, transparent 1px),
                linear-gradient(to bottom, rgba(233, 193, 118, 0.03) 1px, transparent 1px);
            background-size: 60px 60px;
        }

        .scan-ring-animation {
            animation: pulse-ring 3s cubic-bezier(0.4, 0, 0.6, 1) infinite;
        }

        @keyframes pulse-ring {

            0%,
            100% {
                opacity: 0.25;
                transform: scale(1);
            }

            50% {
                opacity: 0.7;
                transform: scale(1.04);
            }
        }

        .fade-in {
            animation: fadeIn 0.4s ease-out forwards;
        }

        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: translateY(8px);
            }

            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        
        ::-webkit-scrollbar {
            width: 8px;
            height: 8px;
        }

        ::-webkit-scrollbar-track {
            background: #111415;
        }

        ::-webkit-scrollbar-thumb {
            background: #2a2e30;
            border-radius: 4px;
        }

        ::-webkit-scrollbar-thumb:hover {
            background: #e9c176;
        }

        
        .glass-card {
            position: relative;
        }

        .glass-card::before {
            content: '';
            position: absolute;
            inset: -1px;
            border-radius: inherit;
            padding: 1px;
            background: radial-gradient(350px circle at var(--mouse-x, 0px) var(--mouse-y, 0px),
                    rgba(233, 193, 118, 0.25),
                    transparent 80%);
            -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
            mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
            -webkit-mask-composite: xor;
            mask-composite: exclude;
            pointer-events: none;
            z-index: 10;
            transition: opacity 0.5s ease;
            opacity: 0;
        }

        .glass-card:hover::before {
            opacity: 1;
        }

        
        header {
            transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1) !important;
        }

        
        #chess-loader-overlay {
            position: fixed !important;
            top: 0 !important;
            left: 0 !important;
            width: 100vw !important;
            height: 100vh !important;
            margin: 0 !important;
            padding: 0 !important;
            box-sizing: border-box !important;
            z-index: 9999;
            background: rgba(8, 9, 12, 0.45); 
            backdrop-filter: blur(6px); 
            -webkit-backdrop-filter: blur(6px);
            display: flex !important;
            justify-content: center !important;
            align-items: center !important;
            opacity: 0;
            pointer-events: none;
            transition: opacity 300ms ease;
        }
        #chess-loader-overlay.visible {
            opacity: 1;
            pointer-events: all;
        }
        .loader-card {
            background: rgba(20, 22, 28, 0.85); 
            border: 1px solid rgba(255, 255, 255, 0.09);
            border-radius: 20px;
            width: 210px;
            height: 230px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            box-shadow: 0 12px 35px rgba(0, 0, 0, 0.45);
            backdrop-filter: blur(25px);
            -webkit-backdrop-filter: blur(25px);
            padding: 10px;
            gap: 4px;
        }
        #chess-3d-loader-canvas {
            width: 130px !important;
            height: 130px !important;
            pointer-events: none;
        }
        .loader-hud {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
            width: 100%;
        }
        #chess-loader-label {
            font-family: 'Manrope', system-ui, sans-serif;
            font-size: 10px;
            font-weight: 800;
            letter-spacing: 0.16em;
            color: #e9c176;
            animation: loader-text-pulse 2.0s ease-in-out infinite;
        }
        .loader-progress-container {
            width: 110px;
            height: 2px;
            background: rgba(255, 255, 255, 0.06);
            border-radius: 9px;
            overflow: hidden;
        }
        .loader-progress-bar {
            width: 0%;
            height: 100%;
            background: linear-gradient(90deg, #b8860b, #e9c176);
            box-shadow: 0 0 6px #e9c176;
            animation: loader-progress-run 3.8s cubic-bezier(0.1, 0.8, 0.2, 1) infinite;
        }
        @keyframes loader-progress-run {
            0% { width: 0%; }
            50% { width: 72%; }
            80% { width: 92%; }
            100% { width: 100%; }
        }
        @keyframes loader-text-pulse {
            0%, 100% { opacity: 0.5; }
            50% { opacity: 1; }
        }

        
        #openings-list-container::-webkit-scrollbar {
            width: 5px;
        }
        #openings-list-container::-webkit-scrollbar-track {
            background: transparent;
        }
        #openings-list-container::-webkit-scrollbar-thumb {
            background: var(--secondary, #b8860b);
            border-radius: 99px;
            opacity: 0.6;
        }
        #openings-list-container::-webkit-scrollbar-thumb:hover {
            background: var(--primary, #3f5f90);
        }