body {
    font-family: "Helvetica", Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #fff;
    color: #222;
}

.container {
    width: 90%;
    max-width: 1000px;
    margin: 20px auto;
}

.site-header {
    background: none;
    text-align: center;
    padding: 8px 0;
    font-size: 1.3rem;
    font-weight: 500;
    border-bottom: 1px solid #ccc;
    margin-bottom: 20px;
}

h2, h3 {
    margin-top: 20px;
    margin-bottom: 10px;
    font-weight: 500;
}

.intro {
    font-size: 0.95rem;
    line-height: 1.5;
}

.audio-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 10px;
}

.audio-item {
    flex: 1 1 200px;
    display: flex;
    flex-direction: column;
    align-items: center;
    font-size: 0.9rem;
}

.audio-item audio {
    margin-top: 5px;
    width: 100%;
}

.spectro-toggle-container {
    text-align: center;
    margin: 10px 0 15px;
}

.toggle-btn {
    background: none;
    border: 1px solid #555;
    color: #333;
    padding: 4px 10px;
    font-size: 0.9rem;
    font-family: inherit;
    cursor: pointer;
    border-radius: 4px;
    transition: background 0.2s, color 0.2s;
}

.toggle-btn:hover {
    background: #f0f0f0;
    color: #000;
}

.audio-spectrograms {
    display: flex;
    flex-direction: column; /* stack vertically */
    align-items: center;    /* center horizontally */
    gap: 20px;
    margin-top: 15px;
}

.spectro-item {
    display: flex;
    flex-direction: column;
    align-items: center; /* center image and caption */
    text-align: center;  /* fallback for caption */
}

.audio-spectrograms img {
    width: 80%;
    max-width: 700px;
    height: auto;
    display: block;
    border: 1px solid #ccc;
    border-radius: 4px;
}

.spectro-caption {
    font-size: 0.85rem;
    color: #333;
    margin-top: 4px;
    display: block;
}

.hidden {
    display: none;
}

footer {
    font-size: 0.85rem;
    text-align: center;
    margin-top: 30px;
    border-top: 1px solid #ccc;
    padding-top: 10px;
    color: #555;
}