/* =========================================
           CORE SYSTEM VARIABLES
           ========================================= */
        :root {
            --neon-cyan: #00f3ff;
            --neon-green: #00ff41;
            --neon-pink: #bc13fe;
            --neon-yellow: #f1c40f;
            --bg-dark: #050505;
            --bg-panel: rgba(10, 15, 20, 0.85);
            --border-color: rgba(0, 243, 255, 0.3);
            --glass-blur: blur(12px);
            --font-main: 'Rajdhani', sans-serif;
            --font-code: 'Share Tech Mono', monospace;
            --font-head: 'Orbitron', sans-serif;
        }

        /* =========================================
           GLOBAL RESET & SCROLLBAR
           ========================================= */
        * {
            box-sizing: border-box;
            scrollbar-width: thin;
            scrollbar-color: var(--neon-cyan) var(--bg-dark);
            -webkit-tap-highlight-color: transparent; /* Remove blue highlight on mobile tap */
        }

        body {
            background-color: var(--bg-dark);
            color: #e0e0e0;
            font-family: var(--font-main);
            margin: 0;
            height: 100vh;
            /* Trên Desktop thì ẩn scroll body, Mobile sẽ handle riêng */
            overflow: hidden; 
            cursor: none; 
        }

        /* Custom Scrollbar */
        ::-webkit-scrollbar { width: 6px; height: 6px; }
        ::-webkit-scrollbar-track { background: #000; }
        ::-webkit-scrollbar-thumb { background: var(--neon-cyan); border-radius: 3px; }

        /* =========================================
           BACKGROUND LAYERS
           ========================================= */
        #bg-canvas, #matrix-canvas {
            position: fixed;
            top: 0; left: 0;
            width: 100%; height: 100%;
            z-index: -1;
        }
        #matrix-canvas { opacity: 0.15; z-index: -2; }

        .scanlines {
            position: fixed;
            top: 0; left: 0; width: 100%; height: 100%;
            background: linear-gradient(rgba(18, 16, 16, 0) 50%, rgba(0, 0, 0, 0.25) 50%), linear-gradient(90deg, rgba(255, 0, 0, 0.06), rgba(0, 255, 0, 0.02), rgba(0, 0, 255, 0.06));
            background-size: 100% 3px, 3px 100%;
            pointer-events: none;
            z-index: 1000;
        }

        /* =========================================
           CUSTOM CURSOR (Desktop Only)
           ========================================= */
        #cursor, #cursor-dot {
            position: fixed;
            pointer-events: none;
            z-index: 99999;
            transform: translate(-50%, -50%);
            border-radius: 50%;
        }
        #cursor {
            width: 20px; height: 20px;
            border: 2px solid var(--neon-cyan);
            transition: width 0.2s, height 0.2s, background 0.2s;
            mix-blend-mode: difference;
        }
        #cursor-dot {
            width: 4px; height: 4px;
            background: var(--neon-green);
        }
        #cursor.hovered {
            width: 40px; height: 40px;
            background: rgba(0, 243, 255, 0.2);
            border-color: var(--neon-pink);
        }

        /* =========================================
           BOOT SCREEN
           ========================================= */
        #boot-screen {
            position: fixed;
            top: 0; left: 0; width: 100vw; height: 100vh;
            background: #000;
            color: var(--neon-green);
            font-family: var(--font-code);
            padding: 20px;
            z-index: 9999;
            display: flex;
            flex-direction: column;
            justify-content: flex-start;
        }
        .boot-line { margin: 2px 0; opacity: 0; animation: fadeIn 0.1s forwards; font-size: 14px; }
        .boot-progress {
            width: 100%; max-width: 300px; height: 20px;
            border: 2px solid var(--neon-green);
            margin-top: 20px;
            display: none;
        }
        .boot-bar { height: 100%; background: var(--neon-green); width: 0%; }

        /* =========================================
           MAIN LAYOUT (GRID SYSTEM)
           ========================================= */
        #main-interface {
            display: none; /* Hidden until boot finishes */
            height: 100vh;
            width: 100vw;
            padding: 15px;
            display: grid;
            /* Grid Areas Design */
            grid-template-areas: 
                "header header header"
                "left center right"
                "footer footer footer";
            grid-template-columns: 320px 1fr 320px;
            grid-template-rows: 60px 1fr 50px;
            gap: 15px;
            opacity: 0;
            transition: opacity 1s;
        }

        /* Areas Assignment */
        .header-bar { grid-area: header; }
        .sidebar-left { grid-area: left; }
        .center-stage { grid-area: center; }
        .sidebar-right { grid-area: right; }
        .footer-bar { grid-area: footer; }

        /* HEADER */
        .header-bar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            border-bottom: 1px solid var(--border-color);
            background: linear-gradient(90deg, rgba(0,0,0,0.9) 0%, rgba(0,243,255,0.1) 50%, rgba(0,0,0,0.9) 100%);
            padding: 0 20px;
            clip-path: polygon(0 0, 100% 0, 100% 80%, 98% 100%, 2% 100%, 0 80%);
        }
        .logo-text {
            font-family: var(--font-head);
            font-size: clamp(18px, 4vw, 24px); /* Responsive Font Size */
            color: var(--neon-cyan);
            text-shadow: 0 0 10px var(--neon-cyan);
            letter-spacing: 2px;
        }
        .system-status { font-family: var(--font-code); font-size: 12px; color: var(--neon-green); text-align: right; }
        .blink { animation: blinker 1s linear infinite; }
        @keyframes blinker { 50% { opacity: 0; } }

        /* COMMON PANEL STYLE */
        .sidebar-left, .sidebar-right, .holo-card, .panel {
            background: var(--bg-panel);
            backdrop-filter: var(--glass-blur);
            border: 1px solid var(--border-color);
        }
        .panel-title {
            background: var(--neon-cyan); color: #000;
            font-family: var(--font-head); font-size: 11px;
            padding: 2px 6px; display: inline-block;
            margin-bottom: 10px; font-weight: bold;
        }

        /* SIDEBAR LEFT (PROFILE) */
        .sidebar-left {
            border-left: 4px solid var(--neon-cyan);
            padding: 20px;
            display: flex; flex-direction: column; align-items: center;
            overflow-y: auto;
        }
        .hex-avatar-container {
            width: 160px; height: 160px;
            margin-bottom: 15px; position: relative;
            flex-shrink: 0;
        }
        .hex-avatar {
            width: 100%; height: 100%;
            background-image: url('https://i.imgur.com/79NuEzl.png');
            background-size: cover; background-position: center;
            clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
            filter: grayscale(80%) sepia(20%) hue-rotate(130deg);
            transition: all 0.5s;
        }
        .hex-border {
            position: absolute; top: -5px; left: -5px; right: -5px; bottom: -5px;
            background: linear-gradient(45deg, var(--neon-cyan), transparent, var(--neon-pink));
            z-index: -1;
            clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
            animation: spinHex 4s linear infinite;
        }
        @keyframes spinHex { 0% { filter: hue-rotate(0deg); } 100% { filter: hue-rotate(360deg); } }
        .sidebar-left:hover .hex-avatar { filter: grayscale(0%); transform: scale(1.05); }

        .profile-name { font-family: var(--font-head); font-size: 24px; color: #fff; margin-top: 5px; text-align: center; }
        .profile-role { color: var(--neon-pink); font-family: var(--font-code); font-size: 14px; margin-bottom: 15px; border: 1px solid var(--neon-pink); padding: 2px 10px; border-radius: 4px; }
        
        .stats-box { width: 100%; margin-top: 10px; border-top: 1px dashed rgba(255,255,255,0.2); padding-top: 15px; }
        .stat-row { display: flex; justify-content: space-between; margin-bottom: 5px; font-size: 12px; font-family: var(--font-code); }
        .progress-bar-custom { width: 100%; height: 4px; background: #333; margin-bottom: 10px; }
        .progress-fill { height: 100%; background: var(--neon-green); width: 0%; transition: width 1s; }

        /* CENTER STAGE (APPS) */
        .center-stage {
            overflow-y: auto;
            padding-right: 5px;
            /* Hide scrollbar for cleaner look but allow scroll */
        }
        .holo-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
            gap: 15px;
            padding-bottom: 20px;
        }
        .holo-card {
            height: 120px;
            display: flex; flex-direction: column; justify-content: center; align-items: center;
            position: relative; overflow: hidden;
            transition: all 0.3s;
            text-decoration: none;
            cursor: pointer;
        }
        .holo-card:hover {
            transform: translateY(-5px);
            border-color: var(--neon-pink);
            box-shadow: 0 0 15px rgba(188, 19, 254, 0.4);
        }
        .card-icon { font-size: 28px; color: var(--neon-cyan); margin-bottom: 10px; transition: 0.3s; }
        .holo-card:hover .card-icon { color: var(--neon-pink); transform: rotateY(180deg); }
        .card-title { color: #fff; font-family: var(--font-head); font-size: 12px; letter-spacing: 1px; text-align: center; }
        .div-logo { width: 35px; height: 35px; background-size: cover; margin-bottom: 5px; filter: drop-shadow(0 0 5px var(--neon-cyan)); }
        .new-badge { position: absolute; top: 0; right: 0; background: var(--neon-yellow); color: #000; font-size: 9px; font-weight: bold; padding: 2px 6px; clip-path: polygon(0 0, 100% 0, 100% 100%, 20% 100%); }

        /* RIGHT SIDEBAR (LOGS & TERMINAL) */
        .sidebar-right {
            display: flex; flex-direction: column; gap: 15px;
            background: transparent; border: none; backdrop-filter: none;
            overflow: hidden;
        }
        .panel { padding: 10px; width: 100%; }
        
        #system-log {
            height: 150px; overflow: hidden;
            font-family: var(--font-code); font-size: 10px; color: var(--neon-green); opacity: 0.8;
            mask-image: linear-gradient(to bottom, transparent 0%, black 20%, black 100%);
        }
        .log-entry { margin-bottom: 2px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

        #terminal-window {
            flex-grow: 1; min-height: 200px;
            background: rgba(0,0,0,0.8); border: 1px solid #333;
            padding: 10px; font-family: var(--font-code); font-size: 12px;
            display: flex; flex-direction: column;
        }
        #terminal-output { flex-grow: 1; overflow-y: auto; color: #ccc; margin-bottom: 10px; word-break: break-all; }
        .cmd-line { display: flex; align-items: center; color: var(--neon-yellow); }
        .prompt { margin-right: 5px; flex-shrink: 0; }
        #cmd-input { background: transparent; border: none; color: #fff; font-family: var(--font-code); width: 100%; outline: none; }

        /* FOOTER */
        .footer-bar {
            display: flex; justify-content: space-between; align-items: center;
            border-top: 1px solid var(--border-color);
            background: rgba(0,0,0,0.95);
            padding: 0 15px;
            z-index: 100;
        }
        .music-player { display: flex; align-items: center; gap: 10px; width: 50%; }
        .visualizer-mini { display: flex; gap: 2px; height: 15px; align-items: flex-end; }
        .v-bar { width: 3px; background: var(--neon-pink); animation: bounce 0.5s infinite; }
        .v-bar:nth-child(even) { background: var(--neon-cyan); animation-duration: 0.4s; }
        @keyframes bounce { 0%,100% {height: 3px} 50% {height: 15px} }
        .song-info-scroller { overflow: hidden; white-space: nowrap; width: 100%; color: var(--neon-cyan); font-size: 11px; font-family: var(--font-code); }
        .system-metrics { display: flex; gap: 15px; font-family: var(--font-code); font-size: 11px; color: #888; white-space: nowrap; }
        .metric-val { color: #fff; font-weight: bold; }

        /* =========================================
           RESPONSIVE MEDIA QUERIES (CRITICAL)
           ========================================= */
        
        /* TABLET & SMALL LAPTOPS (Max 1024px) */
        @media (max-width: 1024px) {
            #main-interface {
                grid-template-columns: 250px 1fr;
                grid-template-areas:
                    "header header"
                    "left center"
                    "right right"
                    "footer footer";
                grid-template-rows: 60px 1fr auto 50px;
            }
            .sidebar-right {
                flex-direction: row; /* Logs and Terminal side by side */
                height: 250px;
            }
        }

        /* MOBILE & TABLET PORTRAIT (Max 768px) */
        @media (max-width: 768px) {
            body {
                overflow-y: auto; /* Enable scroll on mobile */
                cursor: auto; /* Restore default cursor */
            }
            #cursor, #cursor-dot { display: none; } /* Hide custom cursor */
            
            #main-interface {
                display: flex !important; /* Switch from Grid to Flex Column */
                flex-direction: column;
                height: auto;
                min-height: 100vh;
                padding: 10px;
                overflow: visible;
                gap: 20px;
            }

            .header-bar {
                position: sticky; top: 0; z-index: 999;
                padding: 10px;
            }

            .sidebar-left { width: 100%; order: 1; }
            .hex-avatar-container { width: 120px; height: 120px; }

            .center-stage { 
                width: 100%; order: 2; 
                overflow: visible; 
            }
            .holo-grid {
                grid-template-columns: repeat(2, 1fr); /* 2 columns on mobile */
            }

            .sidebar-right { 
                width: 100%; order: 3; 
                flex-direction: column; 
                height: auto;
                display: flex !important; /* Force show */
            }
            #terminal-window { min-height: 250px; }

            .footer-bar {
                position: fixed; bottom: 0; left: 0; width: 100%;
                padding: 5px 10px;
            }
            .system-metrics { display: none; /* Hide FPS on tiny screens */ }
            .music-player { width: 100%; }
            
            /* Add padding bottom so footer doesn't cover content */
            #main-interface { padding-bottom: 60px; }
        }