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

.lesson-page-header h1 {
    font-size: 17px;
    margin-bottom: 4px;
}

.lesson-page-header p {
    font-size: 11px;
    color: #85899b;
}


/* Main */

.lesson-page {
    padding: 18px 16px 30px;
}


/* Lesson Info */

.lesson-info-card {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 18px;
    border-radius: 21px;
    background: linear-gradient(
        135deg,
        #5b5bd6,
        #7971e8
    );
    color: #ffffff;
    margin-bottom: 22px;
}

.lesson-big-icon {
    width: 56px;
    height: 56px;
    border-radius: 17px;
    background: rgba(255,255,255,.18);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    flex-shrink: 0;
}

.lesson-label {
    font-size: 10px;
    opacity: .75;
}

.lesson-info-card h2 {
    font-size: 17px;
    margin: 4px 0;
}

.lesson-info-card p {
    font-size: 11px;
    opacity: .85;
}


/* Section */

.content-section {
    margin-bottom: 25px;
}

.section-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.section-title h2 {
    font-size: 17px;
}

.section-title p {
    color: #85899b;
    font-size: 11px;
    margin-top: 4px;
}

.page-count {
    background: #eeeeff;
    color: #5555c9;
    padding: 7px 10px;
    border-radius: 10px;
    font-size: 11px;
}


/* PDF */

.pdf-card {
    background: #ffffff;
    border: 1px solid #eceef5;
    border-radius: 19px;
    padding: 15px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.pdf-icon {
    width: 48px;
    height: 48px;
    border-radius: 14px;
    background: #fff0f0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 23px;
}

.pdf-info {
    flex: 1;
}

.pdf-info h3 {
    font-size: 14px;
    margin-bottom: 5px;
}

.pdf-info p {
    font-size: 11px;
    color: #85899b;
}

.pdf-arrow {
    color: #5b5bd6;
    font-size: 20px;
}


/* Book */

.book-container {
    background: #e9e9f2;
    border-radius: 20px;
    padding: 10px;
    overflow: hidden;
}

.book {
    position: relative;
    width: 100%;
    aspect-ratio: 3 / 4;
    background: #ffffff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,.10);
}

.book-page {
    position: absolute;
    inset: 0;
    display: none;
    background: #ffffff;
}

.book-page.active {
    display: block;
    animation: pageIn .25s ease;
}

.book-page img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    user-select: none;
    -webkit-user-drag: none;
}


@keyframes pageIn {

    from {
        opacity: 0;
        transform: translateX(18px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }

}


/* Controls */

.book-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 4px 2px;
}

.book-controls span {
    font-size: 12px;
    color: #555b70;
}

.book-btn {
    width: 42px;
    height: 38px;
    border: 0;
    border-radius: 12px;
    background: #ffffff;
    color: #5555c9;
    font-size: 20px;
}

.book-btn:disabled {
    opacity: .35;
}

.swipe-help {
    text-align: center;
    color: #85899b;
    font-size: 11px;
    margin-top: 10px;
}


/* Empty */

.no-pages {
    background: #ffffff;
    border: 1px solid #eceef5;
    border-radius: 20px;
    padding: 40px 20px;
    text-align: center;
}

.no-pages div {
    font-size: 45px;
    margin-bottom: 12px;
}

.no-pages h3 {
    font-size: 15px;
    margin-bottom: 7px;
}

.no-pages p {
    color: #85899b;
    font-size: 11px;
    line-height: 1.5;
}