/* --- Layout tweaks --- */
body {
    background: #f5f7fb;
}
.brand-mark {
    width: 28px;
    height: 28px;
    border-radius: 8px;
    background: #0d6efd;
    display: inline-block;
}
.page-hero {
    background: #3f5e9a; /* close to screenshot */
    color: #fff;
}
.page-hero h1 {
    font-size: 1.5rem;
    letter-spacing: 0.05em;
}
.content-card {
    border: 0;
    box-shadow: 0 8px 24px rgba(16, 24, 40, 0.06);
}
.question-card {
    border: 0;
    box-shadow: 0 8px 24px rgba(16, 24, 40, 0.06);
}
/* Highlight unanswered required question */
.question-card.is-invalid {
    border: 1px solid #dc3545;
    box-shadow: 0 0 0 0.15rem rgba(220, 53, 69, 0.25);
}
.question-title {
    font-weight: 600;
    font-size: 0.95rem;
}
.option-item {
    display: flex;
    align-items: center; /* vertical center */
    justify-content: center; /* horizontal center */
    text-align: center;
    cursor: pointer;
    border: 0;
    padding: 0.9rem 1rem;
    background: #f2f4f8;
    margin-bottom: 0.5rem;
    border-radius: 0.5rem;
}
.option-item:last-child {
    margin-bottom: 0;
}
.list-group .option-item.active {
    background: #3f5e9a;
    border-color: transparent;
}
/* Hide native radio but keep it accessible */
.option-item .form-check-input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}
.muted-note {
    color: #6c757d;
}