        :root {
            --bg: #1a1b26;
            --fg: #c0caf5;
            --panel: #24283b;
            --border: #414868;
            --accent: #7aa2f7;
            --muted: #565a6e;
            --ok: #9ece6a;
            --warn: #e0af68;
            --err: #f7768e;
            --chip: #414868;
        }

        [data-theme="light"] {
            --bg: #d5d6db;
            --fg: #343b58;
            --panel: #e1e2e7;
            --border: #9699a3;
            --accent: #34548a;
            --muted: #9699a3;
            --ok: #485e30;
            --warn: #8f5e15;
            --err: #8c4351;
            --chip: #d5d6db;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: var(--bg);
            color: var(--fg);
            line-height: 1.6;
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            transition: background-color 0.3s ease, color 0.3s ease;
        }

        .error-container {
            max-width: 600px;
            padding: 2rem;
            text-align: center;
            transition: all 0.3s ease;
        }

        .error-icon {
            font-size: 4rem;
            margin-bottom: 1rem;
            color: var(--err);
        }

        .error-code {
            font-size: 3rem;
            font-weight: bold;
            color: var(--accent);
            margin-bottom: 0.5rem;
        }

        .error-title {
            font-size: 1.5rem;
            font-weight: 600;
            margin-bottom: 1rem;
            color: var(--fg);
        }

        .error-message {
            font-size: 1rem;
            color: var(--muted);
            margin-bottom: 2rem;
            line-height: 1.6;
        }

        .error-details {
            background: var(--panel);
            border: 1px solid var(--border);
            border-radius: 8px;
            padding: 1rem;
            margin-bottom: 2rem;
            text-align: left;
            font-family: 'Monaco', 'Menlo', 'Ubuntu Mono', monospace;
            font-size: 0.9rem;
            color: var(--muted);
        }

        .btn {
            display: inline-block;
            padding: 0.75rem 1.5rem;
            background: var(--accent);
            color: white;
            text-decoration: none;
            border-radius: 6px;
            font-weight: 500;
            transition: all 0.2s ease;
            border: none;
            cursor: pointer;
            font-size: 1rem;
        }

        .btn:hover {
            background: var(--accent);
            opacity: 0.9;
            transform: translateY(-1px);
        }

        .btn-secondary {
            background: var(--chip);
            color: var(--fg);
            border: 1px solid var(--border);
        }

        .btn-secondary:hover {
            background: var(--border);
        }

        .btn-group {
            display: flex;
            gap: 1rem;
            justify-content: center;
            flex-wrap: wrap;
        }

        .theme-toggle {
            position: fixed;
            top: 1rem;
            right: 1rem;
            background: var(--panel);
            border: 1px solid var(--border);
            border-radius: 50%;
            width: 48px;
            height: 48px;
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: all 0.2s ease;
            font-size: 1.2rem;
            color: var(--fg);
            z-index: 1000;
        }

        .theme-toggle:hover {
            background: var(--border);
            transform: scale(1.1);
        }

        .theme-toggle:active {
            transform: scale(0.95);
        }

        .auth-notice {
            background: var(--warn);
            color: var(--bg);
            padding: 1rem;
            border-radius: 6px;
            margin-bottom: 1rem;
            font-weight: 500;
        }

        .footer {
            margin-top: 2rem;
            padding-top: 1rem;
            border-top: 1px solid var(--border);
            color: var(--muted);
            font-size: 0.9rem;
        }

        .footer a {
            color: var(--accent);
            text-decoration: none;
        }

        .footer a:hover {
            text-decoration: underline;
        }

        @media (max-width: 768px) {
            .error-container {
                padding: 1rem;
            }
            
            .error-code {
                font-size: 2rem;
            }
            
            .error-title {
                font-size: 1.25rem;
            }
            
            .btn-group {
                flex-direction: column;
                align-items: center;
            }
            
            .btn {
                width: 100%;
                max-width: 300px;
            }
            
            .theme-toggle {
                top: 0.5rem;
                right: 0.5rem;
                width: 40px;
                height: 40px;
                font-size: 1rem;
            }
