body {
    font-family: 'Roboto', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #121212;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    flex-direction: column;
}
h1 {
    color: #007BFF;
    font-size: 30px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 20px;
    position: relative;
    display: inline-block;
    padding: 10px 20px;
    background: linear-gradient(45deg, #a37bf2, #44d0ed);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: gradient 5s infinite;
}
@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}
.card {
    width: 100%;
    height : fit-content;
    max-width: 500px;
    background: #1f1f1f;
    color: #fff;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}
.card h2 {
    margin-bottom: 20px;
    font-size: 24px;
    color: #fff;
}
.card label {
    margin: 0 0 10px;
    font-weight: bold;
    color: #00BFFF;
}
.card input,
.card select,
.card textarea {
    margin-bottom: 20px;
    padding: 10px;
    border: none;
    background: #2c2c2c;
    color: #fff;
    font-size: 16px;
    border-radius: 5px;
    transition: background 0.3s, color 0.3s;
}
.card input:focus,
.card select:focus,
.card textarea:focus {
    background: #444;
    color: #fff;
    outline: none;
}

.card input[readonly] {
    background: #2c2c2c;
    color: #fff;
}

.card input[type="submit"] {
    background: #007BFF;
    color: #fff;
    font-size: 18px;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s, color 0.3s;
}
.card input[type="submit"]:hover {
    background: #0056b3;
    color: #fff;
}
.card a {
    text-decoration: none;
    font-size: 12px;
    line-height: 20px;
    color: darkgrey;
    transition: color 0.3s;
}
.card a:hover {
    color: #00BFFF;
}
.hidden {
    display: none;
}
.input-group-append button {
    background: #007BFF;
    color: white;
    border: none;
    border-radius: 0 5px 5px 0;
    padding: 10px;
    cursor: pointer;
    margin: 0;
}
.input-group button:first-child {
    border-radius: 5px 0 0 5px;
}
.input-group button {
    border-radius: 0;
}
@media (max-width: 600px) {
    .card {
        width: 100%;
        padding: 15px;
    }
    .card h2 {
        font-size: 20px;
    }
    .form-row {
        flex-direction: column;
    }
    .form-row .form-group {
        width: 100%;
    }
}

.radio-group {
    display: flex;
    gap: 10px;
    align-items: center;
}
.radio-group label {
    display: flex;
    align-items: center;
}

.inline-group {
    display: flex;
    justify-content: space-between;
}
.inline-group div {
    width: 45%;
}

.increment-decrement {
    display: flex;
    align-items: center;
}

.increment-decrement button {
    background: #007BFF;
    color: white;
    border: none;
    border-radius: 5px;
    padding: 10px;
    cursor: pointer;
    margin: 0 5px;
}

.increment-decrement input {
    width: 50px;
    text-align: center;
    margin: 0 5px;
}