.custom-input-container {
    position: relative;
}

.custom-input {
    border: none;
    border-radius: 0;
    border-bottom: 1px solid #ced4da;
    padding: 8px 0;
    transition: border-bottom-color 0.3s, box-shadow 0.3s;
}

.custom-input:focus {
    outline: none;
    border-bottom-color: #007bff;
    box-shadow: none;
}

.custom-input.error {
    border-bottom-color: #dc3545;
    box-shadow: 0 0 5px rgba(220, 53, 69, 0.5);
}

.custom-label {
    position: absolute;
    top: 0;
    left: 0;
    margin-top: 5px;
    color: #495057;
    transition: all 0.3s;
    pointer-events: none;
    font-size: 15px;
}

.custom-input:focus~.custom-label,
.custom-input:not(:placeholder-shown)~.custom-label {
    font-size: 0.75em;
    margin-top: -10px;
    color: #007bff;
}