.lesson-header {
    background: #ffffff;
    padding: 16px;
    display: flex;
    align-items: center;
    gap: 12px;
    border-bottom: 1px solid #eceef5;
}

.back-button {
    width: 42px;
    height: 42px;
    border-radius: 13px;
    background: #f0f1ff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    color: #5555c9;
    flex-shrink: 0;
}

.lesson-header-info {
    display: flex;
    align-items: center;
    gap: 11px;
}

.lesson-subject-icon {
    width: 45px;
    height: 45px;
    border-radius: 14px;
    background: #eeeeff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
}

.lesson-header-info h1 {
    font-size: 18px;
    margin-bottom: 4px;
}

.lesson-header-info p {
    color: #85899b;
    font-size: 12px;
}


/* Content */

.lessons-content {
    padding: 20px 16px 30px;
}


/* Intro */

.lesson-intro {
    background: linear-gradient(
        135deg,
        #5b5bd6,
        #7971e8
    );
    color: #ffffff;
    padding: 20px;
    border-radius: 21px;
    margin-bottom: 18px;
}

.lesson-intro h2 {
    font-size: 17px;
    margin-bottom: 7px;
}

.lesson-intro p {
    font-size: 12px;
    opacity: .85;
}


/* Lesson List */

.lessons-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}


/* Lesson Card */

.lesson-card {
    background: #ffffff;
    border: 1px solid #eceef5;
    border-radius: 19px;
    padding: 14px;
    display: flex;
    align-items: center;
    gap: 13px;
    transition: transform .15s ease;
}

.lesson-card:active {
    transform: scale(.98);
}


/* Number */

.lesson-number {
    width: 48px;
    height: 48px;
    border-radius: 15px;
    background: #eeeeff;
    color: #5757c9;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 17px;
    font-weight: bold;
    flex-shrink: 0;
}


/* Information */

.lesson-info {
    flex: 1;
    min-width: 0;
}

.lesson-info h3 {
    font-size: 15px;
    line-height: 1.35;
    margin-bottom: 5px;
}

.lesson-info p {
    color: #85899b;
    font-size: 11px;
    line-height: 1.4;
}


/* Arrow */

.lesson-arrow {
    width: 34px;
    height: 34px;
    border-radius: 11px;
    background: #f4f4ff;
    color: #5b5bd6;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 17px;
}


/* Empty */

.lesson-empty {
    background: #ffffff;
    border: 1px solid #eceef5;
    border-radius: 20px;
    text-align: center;
    padding: 45px 20px;
}

.empty-icon {
    font-size: 45px;
    margin-bottom: 12px;
}

.lesson-empty h3 {
    font-size: 16px;
    margin-bottom: 7px;
}

.lesson-empty p {
    color: #85899b;
    font-size: 12px;
}