:root {
            --bg: #ffffff;
            --text: #1a1a1a;
            --primary: #2563eb;
            --card: #f8fafc;
            --border-color: #dddddd;
        }

        [data-theme="dark"] {
            --bg: #0f172a;
            --text: #f8fafc;
            --primary: #3b82f6;
            --card: #1e293b;
            --border-color: #334155;
        }

        * {
            transition: background-color 0.5s cubic-bezier(0.4, 0, 0.2, 1), 
                        color 0.5s cubic-bezier(0.4, 0, 0.2, 1), 
                        border-color 0.5s cubic-bezier(0.4, 0, 0.2, 1);
            box-sizing: border-box;
        }

        body {
            font-family: system-ui, sans-serif;
            background-color: var(--bg);
            color: var(--text);
            margin: 0;
            display: flex;
            flex-direction: column;
            height: 100vh; /* Lock height to viewport yk */
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 1rem 2rem;
            width: 100%;
        }

        .back-link {
            text-decoration: none;
            color: var(--text);
            opacity: 0.7;
            font-weight: 500;
        }

        .back-link:hover { opacity: 1; transform: translateX(-3px); }

        #theme-toggle {
            background: none;
            border: 1px solid var(--text);
            color: var(--text);
            padding: 5px 10px;
            cursor: pointer;
            border-radius: 4px;
        }

        /* Centered area */

        .main-content {
            flex: 1;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            text-align: center;
            padding: 2rem;
        }

        .btn {
            background: var(--primary);
            color: white !important;
            padding: 12px 24px;
            text-decoration: none;
            border-radius: 5px;
            display: inline-block;
            margin-top: 20px;
            font-weight: bold;
        }

        .email-section {
            margin-top: 4rem;
        }

        .copy-zone {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
            min-height: 50px;
        }

        #myEmail {
            font-weight: bold;
            font-size: 1.1rem;
            cursor: pointer;
            color: var(--primary);
            transition: 0.2s;
        }

        #copyFeedback {
            font-size: 0.8rem;
            opacity: 0;
            transition: 0.3s;
            color: var(--primary);
            font-weight: bold;
        }