body {
    margin: 0;
    padding: 0;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #f8fafc;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}
.converter-card {
    background: white;
    padding: 24px 32px;
    border-radius: 16px;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    width: 350px;
    text-align: center;
}
h2 {
    margin-top: 0;
    color: #1e293b;
    margin-bottom: 24px;
}
.input-group {
    display: flex;
    flex-direction: column;
    text-align: left;
}
label {
    font-size: 14px;
    font-weight: 600;
    color: #475569;
    margin-bottom: 8px;
}
input {
    padding: 12px;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    font-size: 16px;
    outline: none;
    transition:
        border-color 0.2s,
        box-shadow 0.2s;
}
input:focus {
    border-color: #3bbef6;
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.1);
}
input[type='number']::-webkit-inner-spin-button,
input[type='number']::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.icon {
    height: 1em;
    width: 1em;
    color: #1e293b;
    border-radius: 50%;
    margin: 1em 0;

    cursor: pointer;
}

.icon:active {
    /* background-color: gray; */
    box-shadow: 0 0 0 10px rgb(148, 163, 184, 0.1);
}