.series-index-page {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
    font-family: sans-serif;
}

.series-letters-nav {
    margin-bottom: 30px;
    text-align: center;
}

.series-letters-nav a {
    display: inline-block;
    margin: 0 5px 10px;
    padding: 6px 12px;
    border: 1px solid #ccc;
    border-radius: 6px;
    text-decoration: none;
    color: #333;
    background-color: #f9f9f9;
    transition: background 0.2s ease;
}

.series-letters-nav a:hover {
    background-color: #e3e3e3;
}

.series-letter-block {
    margin-bottom: 15px;
    scroll-margin-top: 10vh;
}

.series-letter-title {
    font-size: 24px;
    border-bottom: 2px solid #ccc;
    padding-bottom: 5px;
    margin-bottom: 10px;
}

.series-list {
    list-style: none;
    padding: 0;
    columns: 3;
    column-gap: 40px;
}

.series-list li {
    margin: 5px 0;
}

.series-list a {
    text-decoration: none;
    color: #0073aa;
}

.series-list a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
  .block_main_left_menu__container.mo-main {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 80%;
    height: 100%;
    background: #fff;
    overflow-y: auto;
    z-index: 1000;
    box-shadow: 2px 0 5px rgba(0,0,0,0.2);
  }

  .menu-toggle {
    display: inline-block;
    background: #eee;
    padding: 10px 15px;
    font-size: 16px;
    border-radius: 4px;
    cursor: pointer;
  }

  .menu-open .block_main_left_menu__container.mo-main {
    display: block;
  }
    .block_main_left_menu__container.mo-main {
        display: none !important;
    }
}