body, html {
    background-image: url('/image/mantu-background.jpg');
    background-size: 100% 120vh;
    min-height: 100vh;
    margin: 0;
    background-repeat: no-repeat;
    background-position: center top;
}

.register-container {
    text-align: center;
    margin-top: 50px;
}

.register-box {
    display: inline-block;
    padding: 20px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    width: 350px;
}

.mantu-logo {
    width: 300px;
    max-width: 100%;
    display: block;
    margin: 0 auto 20px;
}

.register-box h2 {
    font-family: Arial, sans-serif;
    color: #662179;
}

.error-message {
    color: red;
    font-weight: bold;
}

.form-register {
    margin-bottom: 20px;
}

.form-register input {
    width: 100%;
    padding: 12px;
    border-radius: 6px;
    border: 1px solid #ccc;
    box-sizing: border-box;
    text-align: center;
}

.form-register input:focus {
    border-color: #a64ca6;
    outline: none;
}

.submit-btn {
    width: 100%;
    padding: 12px;
    background-color: #662179;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    cursor: pointer;
    transition: 0.3s;
}

.submit-btn:hover {
    background-color: #4b0c68;
}

.register-header {
    position: static;
    top: 0;
    left: 0;
    z-index: 1000;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    padding: 10px 16px;
    background: #fff;
    border-bottom: 1px solid #eee;
}

.btn-back {
    display: inline-block;
    padding: 8px 16px;
    background-color: #662179;
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 14px;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-back:hover {
    background-color: #50185c;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 33, 121, 0.3);
}

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

/* ===== ENHANCED INTERACTIVITY ===== */
.register-box {
    transition: all 0.3s ease;
}

.register-box:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.15);
}

.form-register input {
    transition: all 0.3s ease;
}

.form-register input:hover {
    border-color: #8b2fa3;
    transform: translateY(-1px);
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 768px) {
    .register-container {
        margin-top: 30px;
        padding: 0 15px;
    }
    
    .register-box {
        width: 90%;
        max-width: 400px;
        padding: 18px;
    }
    
    .mantu-logo {
        width: 250px;
    }
    
    .register-header {
        padding: 8px 12px;
    }
    
    .btn-back {
        padding: 6px 12px;
        font-size: 13px;
    }
}

@media (max-width: 480px) {
    .register-container {
        margin-top: 20px;
        padding: 0 10px;
    }
    
    .register-box {
        width: 95%;
        padding: 15px;
    }
    
    .mantu-logo {
        width: 200px;
    }
    
    .form-register input {
        padding: 10px;
        font-size: 14px;
    }
    
    .submit-btn {
        padding: 10px;
        font-size: 14px;
    }
}