.stage4 {
    position: relative;
    width: 100%;
    overflow: hidden;
    background: #fbfbfd;
    scroll-margin-top: 7rem;
}

.stage4__inner {
    display: grid;
    width: min(var(--container-width), calc(100% - (var(--page-gutter) * 2)));
    grid-template-columns: minmax(28rem, 0.7fr) minmax(0, 1.3fr);
    gap: 10rem;
    align-items: start;
    margin-inline: auto;
    padding: 12rem 0;
}

.stage4__intro {
    position: sticky;
    top: 11rem;
}

.stage4__eyebrow {
    margin: 0 0 1.6rem;
    color: var(--brand-purple);
    font-size: 1.1rem;
    font-weight: 800;
    letter-spacing: 0.13em;
    text-transform: uppercase;
}

.stage4__intro h2 {
    margin: 0;
    font-size: 5.6rem;
    font-weight: 770;
    letter-spacing: -0.06em;
    line-height: 1.02;
}

.stage4__intro h2 span {
    color: transparent;
    background: var(--brand-gradient);
    background-clip: text;
    -webkit-background-clip: text;
}

.stage4__intro > p:not(.stage4__eyebrow) {
    max-width: 36rem;
    margin: 2.3rem 0 0;
    color: var(--color-text-muted);
    font-size: 1.4rem;
    line-height: 1.75;
}

.stage4__intro-mark {
    display: grid;
    width: 10rem;
    height: 10rem;
    margin-top: 4rem;
    place-items: center;
    color: #ffffff;
    background: var(--color-text);
    border-radius: 50%;
    box-shadow:
        0 0 0 0.7rem #fbfbfd,
        0 0 0 0.8rem rgba(17, 17, 22, 0.25),
        1.2rem 1.2rem 0 rgba(0, 205, 255, 0.28);
    font-size: 4.6rem;
    font-weight: 300;
    transform: rotate(-7deg);
}

.stage4__list {
    border-top: 0.1rem solid var(--color-border);
}

.stage4__item {
    border-bottom: 0.1rem solid var(--color-border);
}

.stage4__item h3 {
    margin: 0;
}

.stage4__item button {
    display: flex;
    width: 100%;
    min-height: 8.8rem;
    align-items: center;
    justify-content: space-between;
    gap: 3rem;
    padding: 2rem 0;
    text-align: left;
    background: transparent;
    border: 0;
}

.stage4__item button > span {
    display: flex;
    align-items: center;
    gap: 2rem;
    font-size: 1.8rem;
    font-weight: 680;
    letter-spacing: -0.02em;
}

.stage4__item button i {
    color: var(--color-text-muted);
    font-size: 1rem;
    font-style: normal;
    font-weight: 700;
    letter-spacing: 0.1em;
}

.stage4__item button > svg {
    width: 2.2rem;
    height: 2.2rem;
    flex: 0 0 auto;
    fill: none;
    stroke: currentColor;
    stroke-width: 1.7;
    stroke-linecap: round;
    transition: color var(--transition-fast), transform 220ms ease;
}

.stage4__item button:hover {
    color: var(--brand-purple);
}

.stage4__item.is-open button > svg {
    color: var(--brand-purple);
    transform: rotate(45deg);
}

.stage4__answer {
    padding: 0 5.5rem 2.8rem 4.1rem;
}

.stage4__answer[hidden] {
    display: none;
}

.stage4__answer p {
    max-width: 66rem;
    margin: 0;
    color: var(--color-text-muted);
    font-size: 1.4rem;
    line-height: 1.8;
}

@media screen and (max-width: 900px) {
    .stage4__inner {
        grid-template-columns: 1fr;
        gap: 6rem;
        padding: 9rem 0;
    }

    .stage4__intro {
        position: static;
    }

    .stage4__intro > p:not(.stage4__eyebrow) {
        max-width: 56rem;
    }

    .stage4__intro-mark {
        display: none;
    }
}

@media screen and (max-width: 640px) {
    .stage4__inner {
        gap: 4.5rem;
        padding: 7.5rem 0;
    }

    .stage4__intro h2 {
        font-size: 4.4rem;
    }

    .stage4__item button {
        min-height: 8rem;
        gap: 1.5rem;
    }

    .stage4__item button > span {
        align-items: flex-start;
        gap: 1.2rem;
        font-size: 1.5rem;
    }

    .stage4__answer {
        padding: 0 3.2rem 2.5rem 2.7rem;
    }

    .stage4__answer p {
        font-size: 1.3rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    .stage4__item button > svg {
        transition: none;
    }
}