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

        body {
            font-family: 'Segoe UI', 'Inter', system-ui, -apple-system, 'Roboto', sans-serif;
            background: linear-gradient(135deg, #0b1120 0%, #111827 100%);
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0;
            padding: 1.5rem;
            position: relative;
        }

        body::before {
            content: "";
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-image: radial-gradient(rgba(255,255,255,0.03) 1px, transparent 1px);
            background-size: 32px 32px;
            pointer-events: none;
            z-index: 0;
        }

        .auth-container {
            width: 100%;
            max-width: 460px;
            background: rgba(18, 25, 45, 0.75);
            backdrop-filter: blur(12px);
            border-radius: 2rem;
            padding: 2rem 2rem 2.2rem;
            box-shadow: 0 25px 45px -12px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(255, 255, 255, 0.05);
            transition: transform 0.2s ease, padding 0.3s ease;
            z-index: 2;
        }

        .auth-container:hover {
            transform: translateY(-2px);
        }

        .brand {
            text-align: center;
            margin-bottom: 2rem;
        }

        .brand h1 {
            font-size: 2.5rem;
            font-weight: 700;
            background: linear-gradient(120deg, #E6F7FF, #A3C7FF);
            background-clip: text;
            -webkit-background-clip: text;
            color: transparent;
            letter-spacing: -0.5px;
            transition: font-size 0.3s ease;
        }

        .brand p {
            color: #8CA3C7;
            font-size: 0.9rem;
            margin-top: 0.5rem;
            transition: font-size 0.3s ease;
        }

        .login-form {
            display: flex;
            flex-direction: column;
            gap: 1.25rem;
        }

        .input-group {
            display: flex;
            flex-direction: column;
            gap: 0.5rem;
        }

        .input-group label {
            font-size: 0.85rem;
            font-weight: 500;
            letter-spacing: 0.3px;
            color: #CBD5E6;
            margin-left: 0.25rem;
            transition: font-size 0.3s ease;
        }

        .input-group input {
            background: #0F172A;
            border: 1px solid #2D3A5E;
            border-radius: 1.25rem;
            padding: 0.9rem 1.25rem;
            font-size: 1rem;
            color: #F1F5F9;
            transition: all 0.2s ease;
            outline: none;
            font-weight: 400;
            width: 100%;
        }

        .input-group input:focus {
            border-color: #5D8BFF;
            box-shadow: 0 0 0 3px rgba(93, 139, 255, 0.2);
            background: #0B1122;
        }

        .input-group input::placeholder {
            color: #4A5B7A;
            font-weight: 400;
            font-size: 0.9rem;
        }

        .submit-btn {
            background: linear-gradient(105deg, #2A5CFF 0%, #3B7CFF 100%);
            border: none;
            border-radius: 2rem;
            padding: 0.9rem;
            font-size: 1rem;
            font-weight: 600;
            color: white;
            cursor: pointer;
            transition: all 0.25s;
            margin-top: 0.5rem;
            box-shadow: 0 4px 12px rgba(42, 92, 255, 0.3);
            letter-spacing: 0.3px;
            width: 100%;
        }

        .submit-btn:hover {
            background: linear-gradient(105deg, #1A4CFF 0%, #2E6CFF 100%);
            transform: scale(1.01);
            box-shadow: 0 8px 20px rgba(42, 92, 255, 0.4);
        }

        .submit-btn:active {
            transform: scale(0.98);
        }

        .register-wrapper {
            text-align: center;
            margin-top: 1.8rem;
            border-top: 1px solid rgba(61, 82, 115, 0.5);
            padding-top: 1.5rem;
        }

        .register-link {
            display: inline-block;
            font-weight: 600;
            font-size: 0.95rem;
            text-decoration: none;
            background: rgba(45, 58, 94, 0.5);
            padding: 0.6rem 1.4rem;
            border-radius: 3rem;
            transition: all 0.2s;
            color: #B9D0FF;
            border: 1px solid rgba(93, 139, 255, 0.3);
        }

        .register-link:hover {
            background: #2D3A5E;
            color: white;
            border-color: #5D8BFF;
            box-shadow: 0 2px 8px rgba(0,0,0,0.2);
        }

        .register-link:active {
            transform: scale(0.98);
        }

        .message-alert {
            background: rgba(0, 0, 0, 0.7);
            backdrop-filter: blur(8px);
            border-left: 4px solid #FFB347;
            border-radius: 1.2rem;
            padding: 0.9rem 1.2rem;
            margin-bottom: 1.5rem;
            color: #FFE6C7;
            font-size: 0.9rem;
            font-weight: 500;
            text-align: center;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            word-break: break-word;
            animation: slideIn 0.3s ease;
        }

        .message-alert.error {
            border-left-color: #FF6B6B;
            background: rgba(180, 60, 50, 0.8);
        }

        .message-alert.success {
            border-left-color: #4ECDC4;
            background: rgba(30, 80, 70, 0.8);
        }

        .message-alert::before {
            content: "ℹ️";
            font-size: 1rem;
        }

        .message-alert.error::before {
            content: "⚠️";
        }

        .message-alert.success::before {
            content: "✓";
        }

        .error-shake {
            animation: shake 0.3s ease-in-out 0s 2;
        }

        @keyframes shake {
            0%, 100% { transform: translateX(0); }
            25% { transform: translateX(-4px); }
            75% { transform: translateX(4px); }
        }

        @keyframes slideIn {
            from {
                opacity: 0;
                transform: translateY(-10px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .security-note {
            text-align: center;
            font-size: 0.7rem;
            color: #5D6F8F;
            margin-top: 1.5rem;
            letter-spacing: 0.2px;
        }

        @media (max-width: 480px) {
            body {
                padding: 1rem;
                align-items: flex-start;
                padding-top: 2rem;
            }

            .auth-container {
                padding: 1.5rem;
                border-radius: 1.5rem;
                max-width: 100%;
            }

            .brand {
                margin-bottom: 1.5rem;
            }

            .brand h1 {
                font-size: 1.8rem;
            }

            .brand p {
                font-size: 0.8rem;
            }

            .input-group label {
                font-size: 0.75rem;
            }

            .input-group input {
                padding: 0.75rem 1rem;
                font-size: 16px !important; 
                border-radius: 1rem;
            }

            .input-group input::placeholder {
                font-size: 0.85rem;
            }

            .submit-btn {
                padding: 0.75rem;
                font-size: 0.95rem;
                min-height: 48px; 
            }

            .register-link {
                padding: 0.5rem 1.2rem;
                font-size: 0.85rem;
                min-height: 44px;
                display: inline-flex;
                align-items: center;
                justify-content: center;
            }

            .register-wrapper {
                margin-top: 1.5rem;
                padding-top: 1.2rem;
            }

            .message-alert {
                padding: 0.75rem 1rem;
                font-size: 0.85rem;
                margin-bottom: 1.2rem;
            }

            .security-note {
                font-size: 0.65rem;
                margin-top: 1.2rem;
            }
        }

        @media (min-width: 481px) and (max-width: 768px) {
            body {
                padding: 1.5rem;
            }

            .auth-container {
                max-width: 420px;
                padding: 1.8rem;
            }

            .brand h1 {
                font-size: 2.2rem;
            }

            .brand p {
                font-size: 0.85rem;
            }

            .input-group input {
                padding: 0.85rem 1.2rem;
            }

            .submit-btn {
                padding: 0.85rem;
            }
        }

        @media (min-width: 769px) and (max-width: 1024px) {
            .auth-container {
                max-width: 440px;
                padding: 2rem;
            }
        }

        @media (min-width: 1025px) and (max-width: 1280px) {
            .auth-container {
                max-width: 460px;
            }
        }

        @media (min-width: 1281px) {
            .auth-container {
                max-width: 500px;
                padding: 2.5rem;
            }

            .brand h1 {
                font-size: 2.8rem;
            }

            .brand p {
                font-size: 1rem;
            }

            .input-group input {
                padding: 1rem 1.5rem;
                font-size: 1.05rem;
            }

            .submit-btn {
                padding: 1rem;
                font-size: 1.05rem;
            }
        }

        @media (max-width: 768px) and (orientation: landscape) {
            body {
                padding: 1rem;
                align-items: center;
            }

            .auth-container {
                padding: 1.2rem;
                max-width: 500px;
            }

            .brand {
                margin-bottom: 1rem;
            }

            .brand h1 {
                font-size: 1.5rem;
            }

            .brand p {
                font-size: 0.7rem;
                margin-top: 0.3rem;
            }

            .login-form {
                gap: 0.8rem;
            }

            .input-group {
                gap: 0.3rem;
            }

            .input-group input {
                padding: 0.6rem 1rem;
            }

            .submit-btn {
                padding: 0.6rem;
                margin-top: 0.2rem;
            }

            .register-wrapper {
                margin-top: 1rem;
                padding-top: 0.8rem;
            }

            .security-note {
                margin-top: 0.8rem;
            }
        }

        @media (max-width: 768px) {
            button,
            .register-link,
            .submit-btn {
                cursor: pointer;
                -webkit-tap-highlight-color: transparent;
            }

            button:active,
            .register-link:active,
            .submit-btn:active {
                transform: scale(0.97);
            }

            .register-link {
                padding: 0.6rem 1.4rem;
            }
        }

        @media (prefers-color-scheme: dark) {
            body {
                background: linear-gradient(135deg, #0a0f1a 0%, #0f172a 100%);
            }

            .auth-container {
                background: rgba(15, 23, 42, 0.85);
            }
        }

        @keyframes fadeIn {
            from {
                opacity: 0;
                transform: translateY(20px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .auth-container {
            animation: fadeIn 0.5s ease-out;
        }

        @media (prefers-reduced-motion: reduce) {
            * {
                animation-duration: 0.01ms !important;
                animation-iteration-count: 1 !important;
                transition-duration: 0.01ms !important;
            }
        }

        @media (max-width: 320px) {
            .auth-container {
                padding: 1.2rem;
            }

            .brand h1 {
                font-size: 1.5rem;
            }

            .brand p {
                font-size: 0.7rem;
            }

            .input-group input {
                padding: 0.65rem 0.9rem;
                font-size: 14px !important;
            }

            .submit-btn {
                padding: 0.65rem;
                font-size: 0.85rem;
            }

            .register-link {
                padding: 0.45rem 1rem;
                font-size: 0.8rem;
            }

            .message-alert {
                padding: 0.6rem 0.8rem;
                font-size: 0.75rem;
            }
        }

        .input-group input:focus-visible,
        .submit-btn:focus-visible,
        .register-link:focus-visible {
            outline: 2px solid #5D8BFF;
            outline-offset: 2px;
        }

        @media (forced-colors: active) {
            .submit-btn,
            .register-link {
                border: 1px solid currentColor;
            }
        }