body{
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #d946ef 100%);
}
.auth-container {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 20px;
        }

        .auth-container *,
        .auth-container *::before,
        .auth-container *::after {
            box-sizing: border-box;
        }

        .form-wrapper {
            position: relative;
            width: 420px;
            height: auto;
            min-height: 680px;
            perspective: 1000px;
        }

        .form-container {
            position: relative;
            width: 100%;
            height: auto;
            min-height: 680px;
            transform-style: preserve-3d;
            transition: transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .form-container.flipped {
            transform: rotateY(180deg);
        }

        .form-side {
            position: absolute;
            width: 100%;
            height: auto;
            min-height: 480px;
            backface-visibility: hidden;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(20px);
            border: 1px solid rgba(255, 255, 255, 0.2);
            border-radius: 24px;
            padding: 32px;
            box-shadow: 0 25px 50px rgba(0, 0, 0, 0.15);
            display: flex;
            flex-direction: column;
            justify-content: flex-start;
        }

        .signup-form {
            transform: rotateY(0deg);
        }

        .login-form {
            transform: rotateY(180deg);
        }

        .form-header {
            text-align: center;
            margin-bottom: 24px;
        }

        .form-title {
            font-size: 28px;
            font-weight: 700;
            color: #1e293b;
            margin: 0 0 8px 0;
            background: linear-gradient(135deg, #6366f1, #8b5cf6);
            background-clip: text;
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .form-subtitle {
            color: #64748b;
            font-size: 14px;
            margin: 0;
        }

        .form-group {
            margin-bottom: 10px;
        }

        .form-label {
            display: block;
            color: #334155;
            font-size: 14px;
            font-weight: 600;
            margin-bottom: 6px;
        }

        .form-input {
            width: 100%;
            padding: 10px 18px;
            border: 2px solid #e2e8f0;
            border-radius: 12px;
            font-size: 16px;
            background: rgba(255, 255, 255, 0.8);
            transition: all 0.3s ease;
            outline: none;
        }

        .form-input:focus {
            border-color: #6366f1;
            background: rgba(255, 255, 255, 1);
            transform: translateY(-2px);
            box-shadow: 0 8px 25px rgba(99, 102, 241, 0.15);
        }

        .form-input::placeholder {
            color: #a0aec0;
        }

        .password-group {
            position: relative;
        }

        .password-toggle {
            position: absolute;
            right: 10px;
            top: 67%;
            transform: translateY(-50%);
            background: none;
            border: none;
            color: #a0aec0;
            cursor: pointer;
            padding: 4px;
            transition: color 0.2s;
        }

        .password-toggle:hover {
            color: #667eea;
        }

        .password-icon {
            width: 20px;
            height: 20px;
        }

        .form-options {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 24px;
            font-size: 14px;
        }

        .checkbox-group {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .form-checkbox {
            width: 16px;
            height: 16px;
            accent-color: #667eea;
        }

        .forgot-link {
            color: #667eea;
            text-decoration: none;
            font-weight: 500;
            transition: color 0.2s;
        }

        .forgot-link:hover {
            color: #764ba2;
        }

        .submit-btn {
            width: 100%;
            background: linear-gradient(135deg, #667eea, #764ba2);
            color: white;
            border: none;
            padding: 16px;
            border-radius: 12px;
            font-size: 16px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
        }

        .submit-btn::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
            transition: left 0.5s;
        }

        .submit-btn:hover::before {
            left: 100%;
        }

        .submit-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 12px 35px rgba(99, 102, 241, 0.3);
        }

        .submit-btn:active {
            transform: translateY(0);
        }

        .form-divider {
            text-align: center;
            margin: 16px 0;
            position: relative;
            color: #94a3b8;
            font-size: 14px;
        }

        .form-divider::before {
            content: '';
            position: absolute;
            top: 50%;
            left: 0;
            right: 0;
            height: 1px;
            background: #e2e8f0;
            z-index: 1;
        }

        .form-divider span {
            background: rgba(255, 255, 255, 0.95);
            padding: 0 16px;
            position: relative;
            z-index: 2;
        }

        .social-login {
            display: flex;
            gap: 12px;
            margin-bottom: 16px;
        }

        .social-btn {
            flex: 1;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 12px;
            border: 2px solid #e2e8f0;
            border-radius: 12px;
            background: rgba(255, 255, 255, 0.8);
            color: #475569;
            text-decoration: none;
            font-weight: 500;
            transition: all 0.3s ease;
        }

        .social-btn:hover {
            border-color: #6366f1;
            background: rgba(255, 255, 255, 1);
            transform: translateY(-2px);
            box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
        }

        .social-icon {
            width: 20px;
            height: 20px;
        }

        .form-switch {
            text-align: center;
            margin-top: 16px;
        }

        .switch-text {
            color: #64748b;
            font-size: 14px;
            margin: 0;
        }

        .switch-link {
            color: #6366f1;
            font-weight: 600;
            cursor: pointer;
            transition: color 0.2s;
        }

        .switch-link:hover {
            color: #8b5cf6;
        }

        .form-row {
            display: flex;
            gap: 12px;
        }

        .form-row .form-group {
            flex: 1;
        }

        .terms-text {
            color: #64748b;
            font-size: 12px;
            line-height: 1.4;
            margin-top: 8px;
            margin-bottom: 16px;
        }

        .terms-link {
            color: #6366f1;
            text-decoration: none;
        }

        .terms-link:hover {
            text-decoration: underline;
        }

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

        .form-side {
            animation: fadeInUp 0.6s ease-out;
        }