/* ======================================================
   BREADCRUMB
====================================================== */

.lesson-breadcrumb-section {
    padding: 18px 0;

    background:
        var(--color-background);

    border-bottom:
        1px solid
        var(--color-border);
}


.lesson-breadcrumb {
    display: flex;

    align-items: center;

    flex-wrap: wrap;

    gap: 9px;

    color:
        var(--color-text-muted);

    font-size: 0.76rem;
}


.lesson-breadcrumb a {
    transition:
        color var(--transition-fast);
}


.lesson-breadcrumb a:hover {
    color:
        var(--color-primary);
}


.lesson-breadcrumb strong {
    color:
        var(--color-text-secondary);
}



/* ======================================================
   HERO
====================================================== */

.lesson-hero {
    position: relative;

    overflow: hidden;

    background:
        radial-gradient(
            circle at 85% 20%,
            rgba(37, 99, 235, 0.11),
            transparent 32%
        ),
        radial-gradient(
            circle at 15% 90%,
            rgba(16, 185, 129, 0.07),
            transparent 28%
        ),
        linear-gradient(
            180deg,
            #f8fbff,
            #ffffff
        );
}


.lesson-hero-container {
    min-height: 600px;

    display: grid;

    grid-template-columns:
        minmax(0, 1.05fr)
        minmax(390px, 0.95fr);

    align-items: center;

    gap: 80px;

    padding-top: 75px;

    padding-bottom: 85px;
}


.lesson-topic-badge {
    width: fit-content;

    display: inline-flex;

    align-items: center;

    gap: 9px;

    margin-bottom: 22px;

    padding: 7px 13px 7px 7px;

    color:
        var(--color-primary-dark);

    background:
        var(--color-primary-light);

    border-radius:
        999px;

    font-size: 0.77rem;

    font-weight: 750;
}


.lesson-topic-badge span {
    width: 31px;

    height: 31px;

    display: grid;

    place-items: center;

    color: #ffffff;

    background:
        var(--color-primary);

    border-radius: 50%;

    font-size: 0.67rem;

    font-weight: 850;
}


.lesson-hero-content h1 {
    max-width: 760px;

    margin-bottom: 24px;

    font-size:
        clamp(
            3rem,
            5.4vw,
            5.2rem
        );

    letter-spacing:
        -0.055em;
}


.lesson-hero-content > p {
    max-width: 650px;

    margin-bottom: 32px;

    color:
        var(--color-text-muted);

    font-size: 1.06rem;
}


.lesson-hero-actions {
    display: flex;

    flex-wrap: wrap;

    gap: 14px;

    margin-bottom: 38px;
}


.lesson-meta {
    display: flex;

    flex-wrap: wrap;

    gap: 24px;
}


.lesson-meta div {
    padding-right: 24px;

    border-right:
        1px solid
        var(--color-border);
}


.lesson-meta div:last-child {
    border-right: 0;
}


.lesson-meta strong,
.lesson-meta span {
    display: block;
}


.lesson-meta strong {
    margin-bottom: 3px;

    color:
        var(--color-text-secondary);

    font-size: 0.82rem;
}


.lesson-meta span {
    color:
        var(--color-text-muted);

    font-size: 0.69rem;
}



/* ======================================================
   HERO NUMBER CARD
====================================================== */

.number-hero-card {
    min-height: 420px;

    display: flex;

    flex-direction: column;

    align-items: center;

    justify-content: center;

    padding: 40px;

    text-align: center;

    color: #ffffff;

    background:
        linear-gradient(
            135deg,
            #2563eb,
            #4f46e5
        );

    border-radius:
        var(--radius-extra-large);

    box-shadow:
        var(--shadow-large);
}


.number-hero-label {
    margin-bottom: 28px;

    color:
        rgba(255, 255, 255, 0.72);

    font-size: 0.72rem;

    font-weight: 800;

    text-transform: uppercase;

    letter-spacing: 0.09em;
}


.number-hero-objects {
    display: flex;

    justify-content: center;

    flex-wrap: wrap;

    gap: 13px;

    margin-bottom: 32px;
}


.number-hero-objects span {
    width: 35px;

    height: 35px;

    display: grid;

    place-items: center;

    color: #ffffff;

    background:
        rgba(255, 255, 255, 0.15);

    border:
        1px solid
        rgba(255, 255, 255, 0.18);

    border-radius: 50%;
}


.number-hero-answer {
    display: flex;

    align-items: center;

    gap: 14px;

    margin-bottom: 18px;
}


.number-hero-answer span {
    color:
        rgba(255, 255, 255, 0.76);
}


.number-hero-answer strong {
    width: 65px;

    height: 65px;

    display: grid;

    place-items: center;

    color:
        var(--color-primary-dark);

    background: #ffffff;

    border-radius: 18px;

    font-size: 2rem;
}


.number-hero-card p {
    max-width: 300px;

    margin-bottom: 0;

    color:
        rgba(255, 255, 255, 0.78);

    font-size: 0.84rem;
}



/* ======================================================
   LESSON PROGRESS
====================================================== */

.lesson-progress-section {
    position: sticky;

    top:
        var(--header-height);

    z-index: 100;

    padding: 12px 0;

    background:
        rgba(255, 255, 255, 0.96);

    border-top:
        1px solid
        var(--color-border);

    border-bottom:
        1px solid
        var(--color-border);

    backdrop-filter:
        blur(14px);
}


.lesson-progress-list {
    display: flex;

    align-items: center;

    justify-content: center;

    flex-wrap: wrap;

    gap: 7px;
}


.lesson-progress-list a {
    display: inline-flex;

    align-items: center;

    gap: 6px;

    padding: 7px 10px;

    color:
        var(--color-text-muted);

    border-radius: 999px;

    font-size: 0.7rem;

    font-weight: 700;

    transition:
        color var(--transition-fast),
        background var(--transition-fast);
}


.lesson-progress-list a:hover {
    color:
        var(--color-primary);

    background:
        var(--color-primary-light);
}


.lesson-progress-list span {
    color:
        var(--color-primary);

    font-size: 0.62rem;
}



/* ======================================================
   SHARED TWO COLUMN
====================================================== */

.lesson-two-column {
    display: grid;

    grid-template-columns:
        minmax(0, 0.78fr)
        minmax(500px, 1.22fr);

    align-items: start;

    gap: 80px;
}


.lesson-heading h2 {
    max-width: 630px;

    margin-bottom: 18px;

    font-size:
        clamp(
            2.2rem,
            4vw,
            3.5rem
        );

    letter-spacing:
        -0.04em;
}


.lesson-heading p {
    max-width: 560px;

    margin-bottom: 0;

    color:
        var(--color-text-muted);
}



/* ======================================================
   OBJECTIVES
====================================================== */

.lesson-objective-section {
    background:
        var(--color-background);
}


.objective-list {
    display: grid;

    grid-template-columns:
        repeat(2, 1fr);

    gap: 14px;
}


.objective-item {
    display: grid;

    grid-template-columns:
        45px 1fr;

    gap: 14px;

    padding: 20px;

    background:
        var(--color-background-soft);

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-medium);
}


.objective-item > span {
    width: 40px;

    height: 40px;

    display: grid;

    place-items: center;

    color:
        var(--color-primary);

    background:
        var(--color-primary-light);

    border-radius: 12px;

    font-size: 0.72rem;

    font-weight: 850;
}


.objective-item p {
    margin:
        auto 0;

    color:
        var(--color-text-secondary);

    font-size: 0.86rem;
}



/* ======================================================
   INTRO
====================================================== */

.lesson-intro-section {
    background:
        var(--color-background-soft);
}


.lesson-intro-card {
    display: grid;

    grid-template-columns:
        minmax(0, 1fr)
        minmax(320px, 0.7fr);

    overflow: hidden;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-extra-large);

    box-shadow:
        var(--shadow-small);
}


.lesson-intro-content {
    padding: 48px;
}


.lesson-mini-label {
    display: block;

    margin-bottom: 12px;

    color:
        var(--color-primary);

    font-size: 0.72rem;

    font-weight: 850;

    text-transform: uppercase;

    letter-spacing: 0.08em;
}


.lesson-intro-content h2 {
    max-width: 600px;

    margin-bottom: 18px;

    font-size:
        clamp(
            2rem,
            4vw,
            3.4rem
        );

    letter-spacing:
        -0.04em;
}


.lesson-intro-content > p {
    max-width: 650px;

    margin-bottom: 28px;

    color:
        var(--color-text-muted);
}


.intro-question {
    padding: 18px;

    background:
        var(--color-primary-light);

    border-radius:
        var(--radius-medium);
}


.intro-question strong,
.intro-question span {
    display: block;
}


.intro-question strong {
    margin-bottom: 4px;

    color:
        var(--color-primary-dark);

    font-size: 0.8rem;
}


.intro-question span {
    color:
        var(--color-text-secondary);

    font-size: 0.84rem;
}



/* INTRO VISUAL */

.intro-hand-demo {
    min-height: 350px;

    display: flex;

    flex-direction: column;

    align-items: center;

    justify-content: center;

    padding: 35px;

    color: #ffffff;

    background:
        linear-gradient(
            135deg,
            #0f766e,
            #059669
        );
}


.finger-group {
    display: flex;

    align-items: flex-end;

    gap: 7px;

    height: 105px;

    margin-bottom: 25px;
}


.finger-group span {
    width: 25px;

    background:
        rgba(255, 255, 255, 0.9);

    border-radius:
        14px 14px 6px 6px;
}


.finger-group span:nth-child(1) {
    height: 58px;
}


.finger-group span:nth-child(2) {
    height: 82px;
}


.finger-group span:nth-child(3) {
    height: 100px;
}


.finger-group span:nth-child(4) {
    height: 88px;
}


.finger-group span:nth-child(5) {
    height: 67px;
}


.intro-hand-demo > strong {
    font-size: 3rem;
}


.intro-hand-demo > small {
    color:
        rgba(255, 255, 255, 0.75);
}



/* ======================================================
   CONCEPT
====================================================== */

.number-concept-section {
    background:
        var(--color-background);
}


.concept-example {
    max-width: 850px;

    display: grid;

    grid-template-columns:
        1fr auto 180px;

    align-items: center;

    gap: 35px;

    margin:
        0 auto 30px;

    padding: 38px;

    background:
        var(--color-background-soft);

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-extra-large);
}


.concept-objects {
    display: flex;

    justify-content: center;

    gap: 18px;
}


.concept-objects span {
    width: 48px;

    height: 48px;

    display: grid;

    place-items: center;

    color:
        var(--color-primary);

    background:
        var(--color-primary-light);

    border-radius: 50%;
}


.concept-arrow {
    color:
        var(--color-text-muted);

    font-size: 1.6rem;
}


.concept-result {
    text-align: center;
}


.concept-result strong,
.concept-result span {
    display: block;
}


.concept-result strong {
    color:
        var(--color-primary);

    font-size: 4rem;

    line-height: 1;
}


.concept-result span {
    margin-top: 8px;

    color:
        var(--color-text-muted);

    font-size: 0.8rem;
}


.concept-explanation {
    display: grid;

    grid-template-columns:
        repeat(3, 1fr);

    gap: 16px;

    max-width: 850px;

    margin-inline: auto;
}


.concept-explanation > div {
    padding: 22px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-medium);
}


.concept-explanation span {
    display: block;

    margin-bottom: 24px;

    color:
        var(--color-primary);

    font-size: 0.7rem;

    font-weight: 850;
}


.concept-explanation h3 {
    margin-bottom: 8px;

    font-size: 0.95rem;
}


.concept-explanation p {
    margin-bottom: 0;

    color:
        var(--color-text-muted);

    font-size: 0.78rem;
}



/* ======================================================
   NUMBER LIST
====================================================== */

.number-list-section {
    background:
        var(--color-background-soft);
}


.number-learning-grid {
    display: grid;

    grid-template-columns:
        repeat(5, minmax(0, 1fr));

    gap: 15px;
}


.number-learning-card {
    min-height: 200px;

    display: flex;

    flex-direction: column;

    align-items: center;

    justify-content: center;

    padding: 18px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-large);

    box-shadow:
        var(--shadow-small);

    text-align: center;
}


.number-learning-card strong {
    color:
        var(--color-primary);

    font-size: 2.8rem;

    line-height: 1;
}


.number-learning-card > span {
    margin-top: 6px;

    color:
        var(--color-text-secondary);

    font-size: 0.8rem;

    font-weight: 700;
}


.number-dots {
    margin-top: 18px;

    color:
        var(--color-primary);

    font-size: 0.72rem;

    letter-spacing: 2px;
}



/* ======================================================
   NUMBER LINE
====================================================== */

.number-line-section {
    background:
        var(--color-background);
}


.number-line-wrapper {
    display: grid;

    grid-template-columns:
        minmax(0, 0.7fr)
        minmax(500px, 1.3fr);

    align-items: center;

    gap: 70px;
}


.number-line-content h2 {
    margin-bottom: 18px;

    font-size:
        clamp(
            2.2rem,
            4vw,
            3.5rem
        );

    letter-spacing:
        -0.04em;
}


.number-line-content p {
    color:
        var(--color-text-muted);
}


.number-line-card {
    padding: 38px 30px;

    background:
        var(--color-background-soft);

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-large);
}


.number-line {
    position: relative;

    display: grid;

    grid-template-columns:
        repeat(11, 1fr);

    gap: 5px;

    margin-bottom: 30px;
}


.number-line::before {
    content: "";

    position: absolute;

    left: 2%;

    right: 2%;

    top: 50%;

    height: 3px;

    background:
        #cbd5e1;

    transform:
        translateY(-50%);
}


.number-line span {
    position: relative;

    z-index: 2;

    width: 33px;

    height: 33px;

    display: grid;

    place-items: center;

    margin-inline: auto;

    color:
        var(--color-primary);

    background: #ffffff;

    border:
        2px solid
        var(--color-primary-light);

    border-radius: 50%;

    font-size: 0.7rem;

    font-weight: 800;
}


.number-line-card p {
    margin-bottom: 0;

    color:
        var(--color-text-muted);

    text-align: center;

    font-size: 0.82rem;
}



/* ======================================================
   INTERACTIVE COUNTER
====================================================== */

.interactive-section {
    background:
        #0f172a;

    color: #ffffff;
}


.interactive-section
.section-eyebrow {
    color:
        #93c5fd;
}


.interactive-section
.section-header p {
    color:
        #94a3b8;
}


.counter-activity {
    max-width: 760px;

    margin-inline: auto;

    padding: 35px;

    background:
        rgba(255, 255, 255, 0.06);

    border:
        1px solid
        rgba(255, 255, 255, 0.10);

    border-radius:
        var(--radius-extra-large);
}


.counter-display {
    min-height: 300px;

    display: flex;

    flex-direction: column;

    align-items: center;

    justify-content: center;

    margin-bottom: 20px;

    padding: 30px;

    background: #ffffff;

    border-radius:
        var(--radius-large);
}


.counter-label {
    margin-bottom: 22px;

    color:
        var(--color-text-muted);

    font-size: 0.72rem;

    font-weight: 800;

    text-transform: uppercase;

    letter-spacing: 0.08em;
}


.counter-objects {
    min-height: 80px;

    display: flex;

    align-items: center;

    justify-content: center;

    flex-wrap: wrap;

    gap: 10px;

    margin-bottom: 24px;
}


.counter-dot {
    width: 30px;

    height: 30px;

    display: block;

    background:
        var(--color-primary);

    border-radius: 50%;

    box-shadow:
        0 4px 12px
        rgba(37, 99, 235, 0.20);
}


.counter-number {
    color:
        var(--color-primary);

    font-size: 4rem;

    line-height: 1;
}


.counter-word {
    margin-top: 8px;

    color:
        var(--color-text-muted);

    font-size: 0.86rem;

    font-weight: 700;
}


.counter-controls {
    display: flex;

    align-items: center;

    justify-content: center;

    flex-wrap: wrap;

    gap: 10px;
}


.counter-button,
.counter-reset {
    min-height: 46px;

    padding: 0 18px;

    color: #ffffff;

    background:
        rgba(255, 255, 255, 0.08);

    border:
        1px solid
        rgba(255, 255, 255, 0.16);

    border-radius: 10px;

    font-weight: 750;
}


.counter-button-primary {
    background:
        var(--color-primary);

    border-color:
        var(--color-primary);
}


.counter-reset {
    color:
        #cbd5e1;
}


.counter-button:disabled {
    opacity: 0.4;

    cursor: not-allowed;
}


.counter-hint {
    margin:
        18px 0 0;

    color:
        #64748b;

    text-align: center;

    font-size: 0.7rem;
}



/* ======================================================
   WORKED EXAMPLE
====================================================== */

.worked-example-section {
    background:
        var(--color-background-soft);
}


.worked-example-card {
    padding: 30px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-large);

    box-shadow:
        var(--shadow-small);
}


.worked-objects {
    display: flex;

    justify-content: center;

    gap: 15px;

    margin-bottom: 30px;

    padding: 35px;

    color:
        var(--color-accent);

    background:
        #fffbeb;

    border-radius:
        var(--radius-medium);

    font-size: 2.2rem;
}


.worked-steps {
    display: grid;

    gap: 10px;
}


.worked-steps > div {
    display: grid;

    grid-template-columns:
        38px 1fr;

    align-items: center;

    gap: 13px;

    padding: 13px;

    background:
        var(--color-background-soft);

    border-radius: 10px;
}


.worked-steps span {
    width: 34px;

    height: 34px;

    display: grid;

    place-items: center;

    color:
        var(--color-primary);

    background:
        var(--color-primary-light);

    border-radius: 50%;

    font-size: 0.7rem;

    font-weight: 800;
}


.worked-steps p {
    margin-bottom: 0;

    color:
        var(--color-text-secondary);

    font-size: 0.83rem;
}



/* ======================================================
   PRACTICE
====================================================== */

.practice-section {
    background:
        var(--color-background);
}


.practice-grid {
    display: grid;

    grid-template-columns:
        repeat(3, minmax(0, 1fr));

    gap: 20px;
}


.practice-card {
    padding: 26px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-large);

    box-shadow:
        var(--shadow-small);
}


.practice-number {
    display: block;

    margin-bottom: 16px;

    color:
        var(--color-primary);

    font-size: 0.68rem;

    font-weight: 850;

    text-transform: uppercase;

    letter-spacing: 0.08em;
}


.practice-card h3 {
    margin-bottom: 22px;

    font-size: 1rem;
}


.practice-objects,
.practice-equation {
    min-height: 100px;

    display: flex;

    align-items: center;

    justify-content: center;

    margin-bottom: 22px;

    color:
        var(--color-primary);

    background:
        var(--color-background-soft);

    border-radius:
        var(--radius-medium);

    font-size: 1.2rem;

    font-weight: 800;

    letter-spacing: 4px;
}


.practice-card details {
    border-top:
        1px solid
        var(--color-border);

    padding-top: 16px;
}


.practice-card summary {
    color:
        var(--color-primary);

    cursor: pointer;

    font-size: 0.8rem;

    font-weight: 750;
}


.practice-card details p {
    margin:
        14px 0 0;

    color:
        var(--color-text-muted);

    font-size: 0.82rem;
}



/* ======================================================
   QUIZ
====================================================== */

.quiz-section {
    background:
        var(--color-background-soft);
}


.quiz-wrapper {
    display: grid;

    grid-template-columns:
        minmax(0, 0.7fr)
        minmax(520px, 1.3fr);

    align-items: start;

    gap: 70px;
}


.quiz-heading h2 {
    margin-bottom: 18px;

    font-size:
        clamp(
            2.2rem,
            4vw,
            3.5rem
        );

    letter-spacing:
        -0.04em;
}


.quiz-heading p {
    color:
        var(--color-text-muted);
}


.quiz-card {
    padding: 28px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-extra-large);

    box-shadow:
        var(--shadow-small);
}


.quiz-question {
    padding:
        20px 0 28px;

    border-bottom:
        1px solid
        var(--color-border);
}


.quiz-question:first-child {
    padding-top: 0;
}


.quiz-question-number {
    display: block;

    margin-bottom: 10px;

    color:
        var(--color-primary);

    font-size: 0.68rem;

    font-weight: 850;
}


.quiz-question h3 {
    margin-bottom: 18px;

    font-size: 1rem;
}


.quiz-objects {
    margin-bottom: 18px;

    color:
        var(--color-primary);

    font-size: 1.15rem;

    letter-spacing: 5px;
}


.quiz-options {
    display: grid;

    grid-template-columns:
        repeat(3, 1fr);

    gap: 9px;
}


.quiz-options button {
    min-height: 45px;

    color:
        var(--color-text-secondary);

    background:
        var(--color-background-soft);

    border:
        1px solid
        var(--color-border);

    border-radius: 10px;

    font-weight: 750;

    transition:
        border-color var(--transition-fast),
        background var(--transition-fast),
        color var(--transition-fast);
}


.quiz-options button:hover {
    border-color:
        var(--color-primary);
}


.quiz-options button.selected {
    color:
        var(--color-primary-dark);

    background:
        var(--color-primary-light);

    border-color:
        var(--color-primary);
}


.quiz-options button.correct {
    color: #047857;

    background: #ecfdf5;

    border-color: #10b981;
}


.quiz-options button.incorrect {
    color: #b91c1c;

    background: #fef2f2;

    border-color: #ef4444;
}


.quiz-footer {
    display: flex;

    align-items: center;

    flex-wrap: wrap;

    gap: 10px;

    padding-top: 25px;
}


.quiz-result {
    width: 100%;

    min-height: 22px;

    margin-top: 8px;

    color:
        var(--color-text-secondary);

    font-size: 0.85rem;

    font-weight: 700;
}



/* ======================================================
   SUMMARY
====================================================== */

.lesson-summary-section {
    background:
        #0f172a;

    color: #ffffff;
}


.lesson-summary-card {
    display: grid;

    grid-template-columns:
        minmax(0, 0.8fr)
        minmax(500px, 1.2fr);

    gap: 70px;

    align-items: center;
}


.lesson-summary-label {
    display: block;

    margin-bottom: 10px;

    color:
        #93c5fd;

    font-size: 0.72rem;

    font-weight: 850;

    text-transform: uppercase;

    letter-spacing: 0.08em;
}


.lesson-summary-heading h2 {
    font-size:
        clamp(
            2.2rem,
            4vw,
            3.6rem
        );

    letter-spacing:
        -0.04em;
}


.lesson-summary-list {
    display: grid;

    grid-template-columns:
        repeat(2, 1fr);

    gap: 12px;
}


.lesson-summary-list > div {
    display: grid;

    grid-template-columns:
        34px 1fr;

    gap: 11px;

    align-items: center;

    padding: 17px;

    background:
        rgba(255, 255, 255, 0.05);

    border:
        1px solid
        rgba(255, 255, 255, 0.10);

    border-radius:
        var(--radius-medium);
}


.lesson-summary-list span {
    width: 30px;

    height: 30px;

    display: grid;

    place-items: center;

    color:
        #6ee7b7;

    background:
        rgba(16, 185, 129, 0.12);

    border-radius: 50%;

    font-size: 0.72rem;
}


.lesson-summary-list p {
    margin-bottom: 0;

    color:
        #cbd5e1;

    font-size: 0.8rem;
}



/* ======================================================
   NEXT LESSON
====================================================== */

.next-lesson-section {
    padding:
        35px 0 70px;

    background:
        var(--color-background);
}


.next-lesson-wrapper {
    display: flex;

    justify-content: space-between;

    gap: 20px;
}


.next-lesson-card {
    min-width: 270px;

    display: flex;

    align-items: center;

    gap: 15px;

    padding: 18px 20px;

    background: #ffffff;

    border:
        1px solid
        var(--color-border);

    border-radius:
        var(--radius-medium);

    transition:
        transform var(--transition-fast),
        border-color var(--transition-fast),
        box-shadow var(--transition-fast);
}


.next-lesson-card:hover {
    transform:
        translateY(-3px);

    border-color:
        rgba(37, 99, 235, 0.28);

    box-shadow:
        var(--shadow-small);
}


.next-lesson-card > span {
    color:
        var(--color-primary);

    font-size: 1.2rem;
}


.next-lesson-card small,
.next-lesson-card strong {
    display: block;
}


.next-lesson-card small {
    margin-bottom: 3px;

    color:
        var(--color-text-muted);

    font-size: 0.67rem;
}


.next-lesson-card strong {
    color:
        var(--color-text-secondary);

    font-size: 0.86rem;
}


.next-lesson-forward {
    justify-content:
        flex-end;

    margin-left:
        auto;

    text-align: right;
}



/* ======================================================
   RESPONSIVE - 1024
====================================================== */

@media (max-width: 1024px) {

    .lesson-hero-container {
        grid-template-columns:
            1fr 390px;

        gap: 45px;
    }


    .lesson-two-column,
    .number-line-wrapper,
    .quiz-wrapper,
    .lesson-summary-card {
        grid-template-columns:
            1fr;

        gap: 45px;
    }


    .number-learning-grid {
        grid-template-columns:
            repeat(3, minmax(0, 1fr));
    }

}



/* ======================================================
   RESPONSIVE - 860
====================================================== */

@media (max-width: 860px) {

    .lesson-hero-container {
        min-height: auto;

        grid-template-columns:
            1fr;

        gap: 50px;

        padding-top: 65px;

        padding-bottom: 70px;
    }


    .lesson-hero-visual {
        width: 100%;

        max-width: 620px;
    }


    .lesson-intro-card {
        grid-template-columns:
            1fr;
    }


    .intro-hand-demo {
        min-height: 280px;
    }


    .practice-grid {
        grid-template-columns:
            1fr;
    }

}



/* ======================================================
   MOBILE
====================================================== */

@media (max-width: 600px) {

    .lesson-breadcrumb-section {
        padding:
            14px 0;
    }


    .lesson-progress-section {
        position: static;
    }


    .lesson-progress-list {
        justify-content:
            flex-start;

        overflow-x: auto;

        flex-wrap: nowrap;

        padding-bottom: 4px;
    }


    .lesson-progress-list a {
        flex-shrink: 0;
    }


    .lesson-hero-container {
        padding-top:
            50px;

        padding-bottom:
            58px;
    }


    .lesson-hero-content h1 {
        font-size:
            clamp(
                2.6rem,
                13vw,
                3.8rem
            );
    }


    .lesson-hero-actions {
        flex-direction:
            column;
    }


    .lesson-hero-actions .button {
        width: 100%;
    }


    .lesson-meta {
        flex-direction:
            column;

        gap: 10px;
    }


    .lesson-meta div {
        padding-right: 0;

        padding-bottom: 10px;

        border-right: 0;

        border-bottom:
            1px solid
            var(--color-border);
    }


    .number-hero-card {
        min-height: 350px;

        padding: 25px;
    }


    .objective-list {
        grid-template-columns:
            1fr;
    }


    .lesson-intro-content {
        padding:
            32px 24px;
    }


    .concept-example {
        grid-template-columns:
            1fr;

        gap: 22px;

        padding: 25px;
    }


    .concept-arrow {
        transform:
            rotate(90deg);

        text-align: center;
    }


    .concept-explanation {
        grid-template-columns:
            1fr;
    }


    .number-learning-grid {
        grid-template-columns:
            repeat(2, minmax(0, 1fr));
    }


    .number-learning-card {
        min-height: 180px;
    }


    .number-line-card {
        overflow-x: auto;

        padding:
            30px 15px;
    }


    .number-line {
        min-width: 560px;
    }


    .counter-activity {
        padding:
            20px;
    }


    .counter-display {
        min-height: 270px;

        padding:
            22px;
    }


    .counter-controls {
        flex-direction:
            column;
    }


    .counter-button,
    .counter-reset {
        width: 100%;
    }


    .quiz-card {
        padding:
            20px;
    }


    .quiz-options {
        grid-template-columns:
            1fr;
    }


    .quiz-footer {
        flex-direction:
            column;

        align-items:
            stretch;
    }


    .quiz-footer .button {
        width: 100%;
    }


    .lesson-summary-list {
        grid-template-columns:
            1fr;
    }


    .next-lesson-wrapper {
        flex-direction:
            column;
    }


    .next-lesson-card {
        width: 100%;

        min-width: auto;
    }


    .next-lesson-forward {
        margin-left: 0;
    }

}