* {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    background: #0f0f0f;
    color: white;
    font-family: Arial, sans-serif;
}

#app {
    max-width: 600px;
    margin: auto;
    min-height: 100vh;
}

.header {
    height: 55px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 15px;

    background: #151515;

    position: sticky;
    top: 0;
    z-index: 10;
}

.header h1 {
    font-size: 16px;
    margin: 0;
}

.header button {
    background: none;
    border: none;
    color: white;
    font-size: 22px;
}

.cover-section {
    width: 100%;
}

.cover {
    width: 100%;
    max-height: 500px;
    object-fit: cover;
    display: block;
}

.info {
    padding: 20px;
}

.info h2 {
    margin-top: 0;
    font-size: 24px;
}

.rating {
    color: #aaa;
    font-size: 14px;
}

.description {
    color: #bbb;
    line-height: 1.6;
}

.buttons {
    display: flex;
    gap: 10px;
}

.buttons button {
    flex: 1;
    padding: 12px;

    border: 0;
    border-radius: 10px;

    background: #252525;
    color: white;
}

.chapters {
    padding: 0 20px 30px;
}

.chapters h2 {
    font-size: 20px;
}

.chapter {
    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 17px;

    margin-bottom: 8px;

    background: #191919;

    border-radius: 10px;

    cursor: pointer;
}

.chapter:hover {
    background: #252525;
}

.reader-header {
    height: 55px;

    display: flex;
    align-items: center;
    justify-content: space-between;

    padding: 0 15px;

    background: #111;
    color: white;

    box-sizing: border-box;
}

.reader-page {
    background: #000;
    overflow: hidden;
}

.reader-header h1 {
    margin: 0;
    font-size: 16px;
}

.reader-header button {
     width: 40px;
    height: 40px;

    border: none;
    background: transparent;

    color: white;
    font-size: 24px;

    cursor: pointer;
}

.reader {
     width: 100%;
    height: calc(100vh - 50px);

    margin: 0;
    padding: 0;

    background: #000;
}

.pdf-viewer {
    display: block;

    width: 100%;
    height: 100%;

    margin: 0;
    padding: 0;

    border: none;
}