@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');
        :root {
            --bg-color: #111827; --form-bg-color: #1F2937; --text-color: #F9FAFB;
            --label-color: #9CA3AF; --border-color: #4B5563; --accent-color: #3B82F6;
            --google-bg: #FFFFFF; --google-text: #1F2937; --error-color: #F87171;
            --success-color: #34D399; --strength-weak: #F87171; --strength-medium: #FBBF24;
            --strength-strong: #34D399;
        }
        body {
            font-family: 'Inter', sans-serif; background-color: var(--bg-color); color: var(--text-color);
            display: flex; justify-content: center; align-items: center; min-height: 100vh;
            margin: 0; padding: 20px; box-sizing: border-box;
        }
        .auth-container {
            width: 100%; max-width: 400px; background-color: var(--form-bg-color);
            padding: 40px; border-radius: 12px; box-shadow: 0 10px 25px rgba(0,0,0,0.3);
            border: 1px solid var(--border-color); animation: fadeIn 0.6s ease-out;
        }
        @keyframes fadeIn { from { opacity: 0; transform: scale(0.95); } to { opacity: 1; transform: scale(1); } }
        h1 { text-align: center; font-size: 24px; font-weight: 700; margin-bottom: 8px; }
        .auth-container > p { text-align: center; color: var(--label-color); margin-bottom: 32px; }
        .social-button {
            display: flex; align-items: center; justify-content: center; width: 100%;
            padding: 12px; border-radius: 8px; font-weight: 500; text-decoration: none;
            transition: all 0.2s; border: 1px solid var(--border-color);
        }
        .google { background-color: var(--google-bg); color: var(--google-text); }
        .google:hover { background-color: #f0f0f0; transform: translateY(-2px); box-shadow: 0 4px 10px rgba(0,0,0,0.2); }
        .google img { width: 20px; margin-right: 12px; }
        .separator { display: flex; align-items: center; text-align: center; color: var(--label-color); margin: 32px 0; }
        .separator::before, .separator::after { content: ''; flex: 1; border-bottom: 1px solid var(--border-color); }
        .separator:not(:empty)::before { margin-right: .25em; }
        .separator:not(:empty)::after { margin-left: .25em; }
        .form-group { margin-bottom: 20px; position: relative; }
        .form-group label { display: block; margin-bottom: 8px; font-size: 14px; color: var(--label-color); }
        .form-group input {
            width: 100%; padding: 12px; background-color: var(--bg-color);
            border: 1px solid var(--border-color); color: var(--text-color); border-radius: 8px;
            box-sizing: border-box; font-size: 16px; transition: all 0.2s;
            /* Add padding-right for icon */
            padding-right: 40px; 
        }
        .form-group input:focus { outline: none; border-color: var(--accent-color); box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.4); }
        
        .form-group input.invalid {
            border-color: var(--error-color);
        }
        .form-group input.invalid:focus {
            box-shadow: 0 0 0 3px rgba(248, 113, 113, 0.4);
        }
        .field-error-message {
            font-size: 13px;
            color: var(--error-color);
            margin-top: 6px;
            display: none; /* Hidden by default */
        }

        .password-toggle {
            position: absolute; right: 10px; top: 39px; background: none; border: none;
            color: var(--label-color); cursor: pointer; padding: 4px; display: flex; align-items: center;
        }
        .password-toggle svg { width: 20px; height: 20px; stroke: var(--label-color); }
        .submit-btn {
            width: 100%; padding: 12px; border: none; border-radius: 8px; background-color: var(--accent-color);
            color: var(--text-color); font-weight: 600; font-size: 16px; cursor: pointer; transition: all 0.2s;
            display: flex; justify-content: center; align-items: center;
        }
        .submit-btn:hover { background-color: #2563EB; transform: translateY(-2px); box-shadow: 0 4px 10px rgba(59, 130, 246, 0.3); }
        .submit-btn:disabled { background-color: #4B5563; cursor: not-allowed; transform: none; box-shadow: none;}
        .loading-spinner {
            width: 20px; height: 20px; border: 2px solid rgba(255,255,255,0.3);
            border-top-color: white; border-radius: 50%; animation: spin 1s linear infinite;
        }
        @keyframes spin { to { transform: rotate(360deg); } }
        .toggle-auth { text-align: center; margin-top: 24px; font-size: 14px; }
        .toggle-auth a { color: var(--accent-color); text-decoration: none; font-weight: 500; cursor: pointer; }
        .message-area { text-align: center; padding: 12px; border-radius: 6px; margin-top: 20px; font-size: 14px; display: none; animation: fadeIn 0.3s; }
        .message-area.error { border: 1px solid var(--error-color); background-color: rgba(239, 68, 68, 0.1); color: var(--error-color); display: block; }
        .message-area.success { border: 1px solid var(--success-color); background-color: rgba(34, 197, 94, 0.1); color: var(--success-color); display: block; }
        .password-strength-meter { display: flex; height: 4px; border-radius: 2px; overflow: hidden; margin-top: 8px; }
        .strength-bar { height: 100%; width: 0; transition: width 0.3s ease-in-out, background-color 0.3s ease-in-out; }
        .strength-bar.weak { width: 33.3%; background-color: var(--strength-weak); }
        .strength-bar.medium { width: 66.6%; background-color: var(--strength-medium); }
        .strength-bar.strong { width: 100%; background-color: var(--strength-strong); }
        .resend-otp { margin-top: 15px; text-align: center; }
        .resend-otp a { color: var(--accent-color); cursor: pointer; font-size: 14px; }
        .resend-otp span { color: var(--label-color); font-size: 14px; }
        .password-validation-message {
            font-size: 13px;
            color: var(--label-color);
            margin-top: 8px;
        }