.lesson-title {
    color: var(--primaryColor);
    font-weight: bold;
}

.content .embed {
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 8px;
    box-shadow: 0 0 8px rgba(0, 0, 0, 0.1);
}

.content .embed iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100% !important;
    height: 100% !important;
    border: none;
}

.content p:first-of-type::first-letter {
    font-size: 2rem;
    font-weight: bold;
    float: left;
    margin-right: 0.6rem;
    background-color: var(--secondaryColor);
    color: var(--black);
    padding: 0.3rem 0.6rem;
    border-radius: 5px;
    line-height: 1;
}

.content p strong {
    font-weight: 600;
    display: block;
    margin-top: 2rem;
}

.content p strong::before {
    content: "";
    display: block;
    height: 2px;
    background: var(--lightGray);
    margin-bottom: 1rem;
}

.content p:last-of-type {
    color: #555;
    font-size: 0.95rem;
    margin-top: 0.2rem;
}

.ss-htmleditorfield-file.embed {
    width: 100% !important;
    max-width: 100% !important;
    margin-bottom: 1.5rem;
    border-radius: 8px;
    overflow: hidden;
}

.ss-htmleditorfield-file.embed iframe {
    width: 100% !important;
    height: auto !important;
    max-width: 100%;
    aspect-ratio: 16 / 9;
    display: block;
    border: none !important;
}

.initial-letter-placeholder {
    width: 60px;
    height: 60px;
    background-color: var(--secondaryColor);
    color: var(--black);
    font-size: 2rem;
    font-weight: bold;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    float: left;
    margin-right: 10px;
    border-radius: 5px;
}

.meta-info {
    font-size: 0.9rem;
    color: #777;
}

.definition-label {
    font-weight: bold;
    margin-top: 1rem;
    color: var(--black);
}

.source {
    font-size: 0.9rem;
    color: #555;
    margin-top: 2rem;
    border-top: 1px solid var(--lightGray);
    padding-top: 1rem;
}

.sidebar {
    height: 315px;
    overflow-y: auto;
    border: 1px solid var(--lightGray);
    border-radius: 5px;
    padding: 0;
    display: flex;
    flex-direction: column;
    background-color: #f9f9f9;
    margin-bottom: 1rem;
}

.sidebar-header {
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--lightGray);
    font-weight: bold;
    background-color: #fff;
    position: sticky;
    top: 0;
    z-index: 1;
}

.sidebar-content {
    overflow-y: auto;
    padding: 1rem;
    flex-grow: 1;
}

.sidebar-content a {
    display: block;
    color: var(--darkBlue);
    text-decoration: none;
    margin-bottom: 0.5rem;
}

.sidebar-content a:hover {
    text-decoration: underline;
}

.sidebar-content .no-results {
    color: var(--gray);
    font-style: italic;
}

/* Highlight para búsqueda */
mark {
    background-color: var(--primaryColor);
    color: white;
    padding: 0 2px;
    border-radius: 2px;
}

/* Alfabeto navegación */
.alphabet {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: start;
}

.alphabet button {
    flex: 0 0 calc(100% / 9 - 0.5rem);
    border: none;
    background: var(--secondaryColor);
    padding: 0.6rem 0;
    border-radius: 4px;
    cursor: pointer;
    font-weight: bold;
    font-size: 1.05rem;
    text-align: center;
    color: var(--black);
    transition: background-color 0.2s;
}

.alphabet button.selected,
.alphabet button:hover {
    background: var(--primaryColor);
    color: white;
}

.alphabet button.disabled {
    background: var(--lightGray);
    color: #999;
    cursor: not-allowed;
    opacity: 0.5;
}