/*
 * Structured learning-content presentation
 * Restrained, practical, and accessible.
 */

:root {
    --learning-charcoal: #26332f;
    --learning-text-soft: #56645f;
    --learning-border: #dce5e1;
    --learning-surface: #ffffff;
    --learning-surface-soft: #f7f9f8;

    --learning-emerald: #24745d;
    --learning-emerald-dark: #185744;
    --learning-emerald-soft: #edf7f3;

    --learning-gold: #a97820;
    --learning-gold-soft: #fbf6e9;

    --learning-neutral: #66756f;
    --learning-neutral-soft: #f1f4f3;

    --learning-radius: 0.85rem;
    --learning-shadow: 0 8px 24px rgba(31, 52, 45, 0.06);
}


/* Lesson sections */

.lesson-section-card {
    position: relative;
    margin-bottom: 1.5rem;
    overflow: hidden;
    border: 1px solid var(--learning-border);
    border-left: 4px solid var(--learning-neutral);
    border-radius: var(--learning-radius);
    background: var(--learning-surface);
    box-shadow: var(--learning-shadow);
    scroll-margin-top: 6rem;
}

.lesson-section-card--learn {
    border-left-color: var(--learning-neutral);
}

.lesson-section-card--practice {
    border-left-color: var(--learning-emerald);
}

.lesson-section-card--required {
    border-left-color: var(--learning-gold);
}

.lesson-section-header {
    padding-bottom: 0.9rem;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--learning-border);
}

.lesson-section-header h2 {
    margin-top: 0.35rem;
    margin-bottom: 0;
    color: var(--learning-charcoal);
    line-height: 1.25;
}

.lesson-section-card--learn .eyebrow {
    color: var(--learning-neutral);
}

.lesson-section-card--practice
.lesson-section-header > div > .badge {
    color: var(--learning-emerald-dark);
    background: var(--learning-emerald-soft);
    border: 1px solid #cce6dc;
}

.lesson-section-card--required
.lesson-section-header > div > .badge {
    color: #755014;
    background: var(--learning-gold-soft);
    border: 1px solid #ead9ae;
}

.lesson-body {
    color: var(--learning-charcoal);
    line-height: 1.72;
}

.lesson-body p,
.lesson-body ul,
.lesson-body ol {
    margin-bottom: 1rem;
}

.lesson-body li + li {
    margin-top: 0.4rem;
}


/* Interactive activity container */

.lesson-activity {
    margin-top: 1.35rem;
    padding: 1.15rem;
    border: 1px solid var(--learning-border);
    border-radius: var(--learning-radius);
    background: var(--learning-surface-soft);
}

.lesson-activity--complete {
    border-color: #cce3da;
    background: var(--learning-emerald-soft);
}

.lesson-activity--pending {
    border-color: #e1d4b8;
    background: #fdfbf6;
}

.lesson-activity-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 0.75rem;
}

.lesson-activity-header > div {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.45rem;
}

.lesson-activity-header h3 {
    flex-basis: 100%;
    margin: 0 0 0.25rem;
    color: var(--learning-charcoal);
    line-height: 1.3;
}


/* Learner status */

.activity-state-badge {
    font-weight: 700;
    letter-spacing: 0.01em;
}

.activity-state-badge--complete {
    color: var(--learning-emerald-dark);
    background: #dcefe7;
    border: 1px solid #b9dacd;
}

.activity-state-badge--pending {
    color: #6b5730;
    background: var(--learning-gold-soft);
    border: 1px solid #e5d5b0;
}

.activity-status-summary {
    display: grid;
    gap: 0.35rem;
    margin: 1rem 0;
    padding: 0.9rem 1rem;
    border: 1px solid rgba(36, 116, 93, 0.15);
    border-radius: 0.7rem;
    background: rgba(255, 255, 255, 0.72);
}

.activity-status-summary h4 {
    margin: 0 0 0.2rem;
    color: var(--learning-charcoal);
    font-size: 0.95rem;
}

.activity-status-summary p {
    margin: 0;
    color: var(--learning-text-soft);
}

.activity-feedback {
    margin-top: 0.5rem;
    padding: 0.8rem;
    border-left: 3px solid var(--learning-emerald);
    border-radius: 0.35rem;
    background: var(--learning-surface);
}


/* Collapsed retry and submission panel */

.activity-form-panel {
    margin-top: 1rem;
    padding-top: 0.85rem;
    border-top: 1px solid var(--learning-border);
}

.activity-form-panel > summary {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    padding: 0.6rem 0.85rem;
    border: 1px solid var(--learning-border);
    border-radius: 0.55rem;
    color: var(--learning-charcoal);
    background: var(--learning-surface);
    font-weight: 700;
    cursor: pointer;
    user-select: none;
    transition:
        border-color 160ms ease,
        background-color 160ms ease,
        color 160ms ease;
}

.activity-form-panel > summary:hover {
    border-color: var(--learning-emerald);
    color: var(--learning-emerald-dark);
    background: var(--learning-emerald-soft);
}

.activity-form-panel > summary:focus-visible {
    outline: 3px solid rgba(36, 116, 93, 0.24);
    outline-offset: 3px;
}

.activity-form-panel[open] > summary {
    margin-bottom: 1rem;
    border-color: var(--learning-emerald);
    color: var(--learning-emerald-dark);
}


/* Questions and choices */

.lesson-activity-form {
    margin-top: 0.5rem;
}

.activity-question {
    min-width: 0;
    margin: 0 0 1rem;
    padding: 1rem;
    border: 1px solid var(--learning-border);
    border-radius: 0.7rem;
    background: var(--learning-surface);
}

.activity-question legend {
    width: auto;
    max-width: 100%;
    padding: 0 0.25rem;
    color: var(--learning-charcoal);
    font-weight: 700;
    line-height: 1.45;
}

.activity-choices {
    display: grid;
    gap: 0.65rem;
    margin-top: 0.75rem;
}

.activity-choice {
    display: flex;
    align-items: flex-start;
    gap: 0.7rem;
    min-height: 44px;
    padding: 0.75rem 0.85rem;
    border: 1px solid var(--learning-border);
    border-radius: 0.6rem;
    background: var(--learning-surface-soft);
    color: var(--learning-charcoal);
    cursor: pointer;
    transition:
        border-color 150ms ease,
        background-color 150ms ease,
        transform 150ms ease;
}

.activity-choice:hover {
    border-color: #9fc9ba;
    background: var(--learning-emerald-soft);
}

.activity-choice:focus-within {
    border-color: var(--learning-emerald);
    outline: 3px solid rgba(36, 116, 93, 0.16);
    outline-offset: 1px;
}

.activity-choice:has(input:checked) {
    border-color: var(--learning-emerald);
    background: var(--learning-emerald-soft);
}

.activity-choice input[type="radio"] {
    flex: 0 0 auto;
    margin-top: 0.2rem;
    accent-color: var(--learning-emerald);
}

.activity-choice span {
    line-height: 1.45;
}


/* Communication form */

.lesson-activity-form .form-field {
    margin-bottom: 1rem;
}

.lesson-activity-form .form-field > label {
    display: block;
    margin-bottom: 0.4rem;
    color: var(--learning-charcoal);
    font-weight: 700;
}

.lesson-activity-form textarea,
.lesson-activity-form input[type="file"] {
    width: 100%;
}

.lesson-activity-form textarea {
    min-height: 7rem;
    resize: vertical;
}

.lesson-activity-form .muted {
    margin-top: 0.4rem;
    color: var(--learning-text-soft);
    font-size: 0.9rem;
}


/* Motion and responsive behavior */

@media (prefers-reduced-motion: reduce) {
    .activity-choice,
    .activity-form-panel > summary {
        transition: none;
    }
}

@media (max-width: 640px) {
    .lesson-section-card {
        border-left-width: 3px;
    }

    .lesson-activity {
        padding: 0.9rem;
    }

    .activity-question {
        padding: 0.85rem;
    }

    .activity-choice {
        padding: 0.7rem;
    }

    .activity-form-panel > summary {
        width: 100%;
        justify-content: center;
    }
}

/* Audio player and transcript */

.lesson-audio-player {
    margin: 1rem 0 1.25rem;
    padding: 1rem;
    border: 1px solid var(--learning-border);
    border-radius: var(--learning-radius);
    background: var(--learning-surface-soft);
}

.lesson-audio-player__header {
    display: flex;
    align-items: center;
    gap: 0.55rem;
    margin-bottom: 0.75rem;
    color: var(--learning-charcoal);
}

.lesson-audio-player__icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex: 0 0 auto;
}

.lesson-audio-player__controls {
    display: block;
    width: 100%;
}

.lesson-audio-transcript {
    margin-top: 0.9rem;
    padding-top: 0.85rem;
    border-top: 1px solid var(--learning-border);
}

.lesson-audio-transcript > summary {
    display: inline-flex;
    align-items: center;
    min-height: 42px;
    padding: 0.55rem 0.8rem;
    border: 1px solid var(--learning-border);
    border-radius: 0.55rem;
    color: var(--learning-emerald-dark);
    background: var(--learning-surface);
    font-weight: 700;
    cursor: pointer;
    user-select: none;
    transition:
        border-color 160ms ease,
        background-color 160ms ease;
}

.lesson-audio-transcript > summary:hover {
    border-color: var(--learning-emerald);
    background: var(--learning-emerald-soft);
}

.lesson-audio-transcript > summary:focus-visible {
    outline: 3px solid rgba(36, 116, 93, 0.22);
    outline-offset: 3px;
}

.lesson-audio-transcript[open] > summary {
    margin-bottom: 0.8rem;
    border-color: var(--learning-emerald);
    background: var(--learning-emerald-soft);
}

.lesson-audio-transcript__panel {
    padding: 1rem 1.1rem;
    border: 1px solid #cfe1da;
    border-left: 4px solid var(--learning-emerald);
    border-radius: 0.7rem;
    background: var(--learning-surface);
    box-shadow: 0 5px 16px rgba(31, 52, 45, 0.05);
}

.lesson-audio-transcript__heading {
    margin: 0 0 0.75rem;
    color: var(--learning-emerald-dark);
    font-size: 0.82rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.lesson-audio-transcript__text {
    color: var(--learning-charcoal);
    line-height: 1.7;
}

.lesson-audio-transcript__text p {
    margin: 0;
}

.lesson-audio-transcript__text p + p {
    margin-top: 0.7rem;
}

@media (max-width: 640px) {
    .lesson-audio-player {
        padding: 0.85rem;
    }

    .lesson-audio-transcript > summary {
        width: 100%;
        justify-content: center;
    }

    .lesson-audio-transcript__panel {
        padding: 0.9rem;
        border-left-width: 3px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .lesson-audio-transcript > summary {
        transition: none;
    }
}