@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;500;700&family=Hind+Siliguri:wght@400;500;600;700&display=swap');

        :root {
            /* Color Variables */
            --bg-color: #ffffff;
            --card-bg-color: #ffffff;
            --text-color: #0f0f0f;
            --secondary-text-color: #606060;
            --subscribe-main-bg: #0f0f0f;
            --subscribe-main-text: #f1f1f1;
            --telegram-bg: #2AABEE;
            --telegram-text: #ffffff;
            --shadow-color: rgba(0, 0, 0, 0.08);
            --loader-main-color: #2AABEE;
            --loader-secondary-color: rgba(42, 171, 238, 0.3);
            --header-bg: rgba(255, 255, 255, 0.95);
        }

        @media (prefers-color-scheme: dark) {
            :root {
                --bg-color: #0f0f0f;
                --card-bg-color: #0f0f0f;
                --text-color: #f1f1f1;
                --secondary-text-color: #aaaaaa;
                --subscribe-main-bg: #f1f1f1;
                --subscribe-main-text: #0f0f0f;
                --shadow-color: rgba(255, 255, 255, 0.1);
                --header-bg: rgba(15, 15, 15, 0.95);
            }
        }

        /* --- পারফরম্যান্স ও স্মুথনেস অপ্টিমাইজেশন --- */
        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Roboto', 'Hind Siliguri', sans-serif;
            background-color: var(--bg-color);
            color: var(--text-color);
            /* এই প্রপার্টিটি মোবাইল/টাচ ডিভাইসে ওভার-স্ক্রল বাউন্স বন্ধ করবে */
            overscroll-behavior-y: contain;
        }

        * { margin: 0; padding: 0; box-sizing: border-box; }

        /* হেডার */
        .top-header {
            display: flex; align-items: center; gap: 12px;
            padding: 12px 16px;
            position: sticky; top: 0;
            background-color: var(--header-bg);
            backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
            z-index: 100;
            border-bottom: 1px solid var(--shadow-color);
        }
        .top-header .yt-logo svg { width: 28px; height: 20px; fill: #FF0000; }
        .top-header .header-title { font-size: 18px; font-weight: 700; }

        .container { max-width: 680px; width: 100%; margin: 0 auto; padding-bottom: 20px; }
        
        /* প্রোফাইল কার্ড */
        .profile-card { width: 100%; background-color: var(--card-bg-color); }
        .banner {
            width: 100%; aspect-ratio: 1060 / 300;
            background-image: url('https://i.ibb.co/vx6vkgnF/channels4-banner.jpg');
            background-size: cover; background-position: center;
        }
        .profile-details { display: flex; align-items: center; gap: 12px; padding: 16px; }
        .profile-logo { width: 80px; height: 80px; border-radius: 50%; }
        .profile-text-info .channel-name { font-size: 24px; font-weight: 700; }
        .profile-text-info .username { font-size: 14px; color: var(--secondary-text-color); }
        
        /* ডেসক্রিপশন */
        .description-box {
            padding: 0 16px 16px 16px; font-size: 14px;
            line-height: 1.5; color: var(--secondary-text-color);
        }
        .description-box .full-desc { display: none; }
        .description-box .more-btn { font-weight: 700; cursor: pointer; color: var(--text-color); }
        
        /* সাবস্ক্রাইব বাটন */
        .subscribe-section { padding: 0 16px 25px 16px; }
        .main-subscribe-button {
            display: block; width: 100%;
            background-color: var(--subscribe-main-bg); color: var(--subscribe-main-text);
            padding: 12px; border-radius: 50px; text-decoration: none;
            font-weight: 700; font-size: 16px; text-align: center;
            transition: transform 0.2s ease-out;
            will-change: transform; /* GPU acceleration for smoother animation */
        }
        .main-subscribe-button:hover { transform: scale(1.02); }

        /* লিঙ্ক সেকশন */
        .links-section {
            width: 100%; display: flex; flex-direction: column;
            gap: 15px; padding: 0 16px;
        }
        .link-button {
            display: flex; align-items: center; justify-content: center;
            gap: 12px; padding: 15px; border-radius: 12px;
            text-decoration: none; font-size: 16px; font-weight: 500;
            transition: transform 0.2s ease-out;
            will-change: transform; /* GPU acceleration for smoother animation */
        }
        .link-button:hover { transform: translateY(-3px); }
        .telegram-button {
            background-color: var(--telegram-bg); color: var(--telegram-text);
            box-shadow: 0 4px 15px -5px var(--telegram-bg);
        }
        .telegram-button svg { fill: var(--telegram-text); width: 24px; height: 24px; }

        /* ফুটার */
        .footer { margin-top: 30px; padding-bottom: 20px; text-align: center; }
        .footer a {
            color: var(--secondary-text-color); text-decoration: none;
            font-size: 14px; font-weight: 500; transition: color 0.2s ease;
        }
        .footer a:hover { color: var(--telegram-bg); }
        
        /* প্রিলোডার (অপরিবর্তিত) */
        #preloader-overlay {
            position: fixed; top: 0; left: 0; width: 100%; height: 100%;
            background-color: var(--bg-color);
            display: flex; justify-content: center; align-items: center;
            z-index: 9999; opacity: 0; pointer-events: none; transition: opacity 0.3s ease;
        }
        #preloader-overlay.visible { opacity: 1; pointer-events: auto; }
        .preloader-content { position: relative; display: flex; justify-content: center; align-items: center; }
        .loader {
            width: 96px; height: 96px; border-radius: 50%;
            background: linear-gradient(0deg, var(--loader-secondary-color) 33%, var(--loader-main-color) 100%);
            animation: rotation 1s linear infinite;
        }
        .loader::after {
            content: ''; position: absolute; left: 50%; top: 50%;
            transform: translate(-50%, -50%);
            width: 88px; height: 88px; border-radius: 50%;
            background: var(--bg-color);
        }
        .preloader-logo {
            position: absolute; width: 75px; height: 75px;
            border-radius: 50%; top: 50%; left: 50%;
            transform: translate(-50%, -50%);
        }
        @keyframes rotation { 0% { transform: rotate(0deg) } 100% { transform: rotate(360deg) } }