/* SimpleAIHub — Lesson 3 only.
   Shared header, course navbar, sidebar, right rail, code controls and footer
   remain in global.css / shared includes. */

.lesson3-page {
    /* Keeps Lesson 3 additions isolated from other lesson pages. */
}

.lesson3-content .callout--plain {
    background: #fff;
    border-color: #e4ddea;
}

.lesson3-content .dl-hierarchy {
    margin: 22px 0;
    padding: 22px;
    border: 1px solid #e3ddec;
    border-radius: 9px;
    background: #fff;
}

.lesson3-content .dl-hierarchy__level {
    border: 1px solid #ded5e9;
    border-radius: 9px;
    padding: 15px 17px;
    margin: 0 auto;
    text-align: center;
}

.lesson3-content .dl-hierarchy__level strong {
    display: block;
    font-size: 18px;
    color: #20263a;
}

.lesson3-content .dl-hierarchy__level span {
    display: block;
    margin-top: 4px;
    color: #59647a;
    font-size: 14px;
}

.lesson3-content .dl-hierarchy__ai {
    max-width: 680px;
    background: #faf9fd;
}

.lesson3-content .dl-hierarchy__ml {
    max-width: 570px;
    margin-top: 12px;
    background: #fcf7ff;
}

.lesson3-content .dl-hierarchy__dl {
    max-width: 460px;
    margin-top: 12px;
    border-color: #d7b7ff;
    background: #f5eaff;
}

.lesson3-content .mini-flow {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 17px;
}

.lesson3-content .mini-flow span,
.lesson3-content .mini-flow strong {
    border: 1px solid #ddd5e8;
    border-radius: 7px;
    padding: 7px 10px;
    background: #faf9fd;
    font-size: 14px;
}

.lesson3-content .mini-flow strong {
    color: #6500cf;
    background: #f5eaff;
    border-color: #d9baff;
}

.lesson3-content .mini-flow b {
    color: #6c00d9;
    font-size: 18px;
}

.lesson3-content .neural-network {
    display: grid;
    grid-template-columns: 1fr 48px 1.25fr 48px 1fr;
    gap: 10px;
    align-items: center;
    margin: 22px 0;
    padding: 20px;
    border: 1px solid #e4deeb;
    border-radius: 9px;
    background: #fff;
    overflow-x: auto;
}

.lesson3-content .neural-network__layer {
    min-height: 160px;
    border: 1px solid #ddd6e7;
    border-radius: 9px;
    background: #faf9fd;
    padding: 14px 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.lesson3-content .neural-network__layer--hidden {
    background: #fcf7ff;
    border-color: #d9baff;
}

.lesson3-content .neural-network__title {
    font-size: 15px;
    font-weight: 800;
    margin-bottom: 3px;
}

.lesson3-content .neural-node {
    min-width: 52px;
    min-height: 31px;
    border: 1px solid #cfc5dc;
    border-radius: 18px;
    background: #fff;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    color: #39435a;
    padding: 4px 9px;
}

.lesson3-content .neural-network__arrow {
    text-align: center;
    color: #7200e8;
    font-size: 25px;
    font-weight: 800;
}

.lesson3-content .training-loop {
    display: grid;
    grid-template-columns: 1fr 34px 1fr 34px 1fr 34px 1fr;
    align-items: center;
    gap: 8px;
    margin: 22px 0;
    padding: 18px;
    border: 1px solid #e3ddec;
    border-radius: 9px;
    background: #fff;
    overflow-x: auto;
}

.lesson3-content .training-loop > div:not(.training-loop__arrow) {
    min-width: 145px;
    border: 1px solid #ddd6e7;
    border-radius: 8px;
    background: #faf9fd;
    padding: 13px 11px;
    text-align: center;
}

.lesson3-content .training-loop strong {
    display: block;
    font-size: 15px;
}

.lesson3-content .training-loop span {
    display: block;
    margin-top: 4px;
    font-size: 13px;
    color: #59647a;
}

.lesson3-content .training-loop__arrow {
    color: #7200e8;
    text-align: center;
    font-size: 20px;
    font-weight: 800;
}

.lesson3-content .comparison-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin: 20px 0;
}

.lesson3-content .comparison-grid > div {
    border: 1px solid #e3ddec;
    border-radius: 9px;
    padding: 17px;
    background: #fff;
}

.lesson3-content .comparison-grid__label {
    color: #6b00d9;
    font-size: 11px;
    font-weight: 800;
    letter-spacing: .6px;
}

.lesson3-content .comparison-grid h3 {
    margin: 7px 0 7px;
}

.lesson3-content .comparison-grid p {
    margin-bottom: 0;
}

.lesson3-content .use-cases {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
    margin: 20px 0;
}

.lesson3-content .use-cases > div {
    border: 1px solid #e4deeb;
    border-radius: 8px;
    padding: 15px;
    background: #fff;
}

.lesson3-content .use-cases strong {
    display: block;
    font-size: 16px;
}

.lesson3-content .use-cases span {
    display: block;
    margin-top: 4px;
    font-size: 14px;
    color: #59647a;
}

.lesson3-content .practice-card--challenge {
    border-color: #d8c8e8;
    background: #fcf9ff;
}

@media (max-width: 760px) {
    .lesson3-content .dl-hierarchy {
        padding: 14px;
    }

    .lesson3-content .dl-hierarchy__level {
        padding: 13px;
    }

    .lesson3-content .dl-hierarchy__level strong {
        font-size: 16px;
    }

    .lesson3-content .mini-flow {
        justify-content: flex-start;
    }

    .lesson3-content .neural-network {
        min-width: 650px;
    }

    .lesson3-content .training-loop {
        min-width: 720px;
    }

    .lesson3-content .comparison-grid,
    .lesson3-content .use-cases {
        grid-template-columns: 1fr;
    }
}