@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700&family=Roboto:wght@400;700&display=swap');

:root {
    --background-color: #121212;
    --primary-color: #00ffff; /* Cyan */
    --secondary-color: #ff00ff; /* Purple */
    --text-color: #e0e0e0;
    --text-color-light: #b0b0b0;
    --control-bg-color: #1e1e1e;
    --border-color: #333;
    --footer-bg-color: #0a0a0a;
}

/* --- General & Typography --- */
body {
    background-color: var(--background-color);
    color: var(--text-color);
    font-family: 'Roboto', sans-serif;
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

*, *:before, *:after {
    box-sizing: inherit;
}

header {
    text-align: center;
    padding: 2rem 1rem;
    border-bottom: 1px solid var(--primary-color);
    text-shadow: 0 0 10px var(--primary-color);
}

h1, h2 {
    font-family: 'Orbitron', sans-serif;
}

h1 {
    font-size: 2.5rem;
    margin: 0;
}

h2 {
    color: var(--primary-color);
    text-shadow: 0 0 8px var(--primary-color);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

main {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 1rem;
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
}

/* --- Tone Generator Main Container --- */
.tone-generator {
    background-color: var(--control-bg-color);
    border-radius: 15px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: 0 0 20px rgba(0, 255, 255, 0.15);
    border: 1px solid var(--border-color);
    width: 100%;
}

/* --- Breadcrumbs --- */
.breadcrumbs {
    font-family: 'Orbitron', monospace;
    font-size: 0.85rem;
    text-transform: uppercase;
    color: #888;
    margin-bottom: 1rem;
    text-align: left;
}

.breadcrumbs a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s ease-in-out;
}

.breadcrumbs a:hover {
    color: var(--primary-color); /* #00ffff */
}

.breadcrumbs .separator {
    margin: 0 0.5rem;
}

/* --- Visualizer --- */
#visualizer {
    width: 100%;
    height: 150px; /* Adjusted height for mobile */
    background-color: #000;
    border: 1px solid var(--primary-color);
    border-radius: 10px;
    margin-bottom: 1.5rem;
}

.controls {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

/* --- Buttons & Inputs --- */
#play-stop-button {
    background-color: var(--primary-color);
    color: #000;
    border: none;
    padding: 1rem;
    font-size: 1.5rem;
    font-family: 'Orbitron', sans-serif;
    cursor: pointer;
    border-radius: 10px;
    text-transform: uppercase;
    box-shadow: 0 0 15px var(--primary-color);
    transition: all 0.2s ease-in-out;
}

#play-stop-button:hover {
    background-color: #fff;
    color: var(--primary-color);
}

.fine-tune-buttons, .radio-group {
    display: flex;
    flex-wrap: wrap; /* CRITICAL: Allows buttons to wrap on small screens */
    justify-content: center;
    gap: 0.5rem;
}

.fine-tune-buttons button {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    padding: 0.5rem 1rem;
    font-family: 'Orbitron', sans-serif;
    cursor: pointer;
    border-radius: 5px;
    flex-grow: 1; /* Allows buttons to take up space */
}

.radio-group input[type="radio"] {
    display: none;
}

.radio-group label {
    cursor: pointer;
    padding: 0.5rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    transition: all 0.2s;
    text-align: center;
    flex-grow: 1;
}

.radio-group input[type="radio"]:checked + label {
    background-color: var(--primary-color);
    color: #000;
    border-color: var(--primary-color);
    text-shadow: none;
}

/* --- Sliders --- */
.slider {
    -webkit-appearance: none;
    width: 100%; /* CRITICAL: Ensures slider fits screen */
    height: 15px; /* Larger touch target */
    background: #333;
    outline: none;
    transition: opacity .2s;
    border-radius: 5px;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 30px; /* Larger touch target */
    height: 30px; /* Larger touch target */
    background: var(--primary-color);
    cursor: pointer;
    border-radius: 50%;
    box-shadow: 0 0 10px var(--primary-color);
}

.slider::-moz-range-thumb {
    width: 30px;
    height: 30px;
    background: var(--primary-color);
    cursor: pointer;
    border-radius: 50%;
    box-shadow: 0 0 10px var(--primary-color);
}


/* --- Content & Article --- */
.content-article {
    width: 100%;
    background-color: var(--control-bg-color);
    padding: 1.5rem;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    margin-bottom: 2rem;
}

.content-article p, .content-article li {
    font-family: 'Roboto', sans-serif;
    color: var(--text-color-light);
    line-height: 1.8;
    font-size: 1.1rem;
}

.content-article ul {
    list-style: none;
    padding-left: 0;
}

.content-article li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.5rem;
}

.content-article li::before {
    content: '»';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}


/* --- Quick Access Grid --- */
.quick-access-grid {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    padding: 1rem;
}

.quick-access-grid .grid-container {
    display: grid;
    grid-template-columns: repeat(4, 1fr); /* 4 columns on desktop */
    gap: 1rem;
}

.quick-access-grid .grid-item {
    background-color: var(--control-bg-color);
    color: var(--text-color);
    text-decoration: none;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    border: 1px solid var(--border-color);
    transition: all 0.2s ease-in-out;
}

.quick-access-grid .grid-item:hover {
    transform: translateY(-5px);
    border-color: var(--secondary-color);
    box-shadow: 0 5px 15px rgba(255, 0, 255, 0.1);
}

.quick-access-grid .grid-item span {
    display: block;
    font-size: 0.8rem;
    color: var(--text-color-light);
    margin-top: 0.25rem;
}

/* --- Footer --- */
footer {
    background-color: var(--footer-bg-color);
    color: var(--text-color-light);
    text-align: center;
    padding: 2rem 1rem;
    margin-top: 3rem; /* Spacing from quick access grid */
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
}

footer p {
    margin-top: 0;
    margin-bottom: 1rem;
}

.footer-links a {
    color: var(--text-color-light);
    text-decoration: none;
    margin: 0 0.5rem;
    transition: color 0.2s ease-in-out;
}

.footer-links a:hover {
    color: var(--primary-color);
}

.footer-links span {
    color: var(--text-color-light);
}


/* --- Media Queries for Responsiveness --- */
@media (max-width: 768px) {
    h1 {
        font-size: 2rem;
    }

    .quick-access-grid .grid-container {
        grid-template-columns: repeat(2, 1fr); /* 2 columns on mobile */
    }
}

@media (max-width: 480px) {
    body {
        padding: 0.5rem;
    }

    main, .quick-access-grid {
        padding: 0;
    }
    
    .tone-generator {
        padding: 1rem;
    }
    
    .fine-tune-buttons {
        grid-template-columns: 1fr 1fr; /* Stack fine-tune buttons */
    }
    
    .footer-links a {
        display: block;
        margin: 0.5rem 0;
    }
    .footer-links span {
        display: none; /* Hide pipe separator on small screens */
    }
}