body {
    margin: 0;
    overflow-x: hidden;
    background-color: black;
    display: flex;
    flex-direction: column;
    align-items: center;
}

canvas {
    width: 100vw;
    height: 100vh;
    display: block;
    position: fixed;
    top: 0;
    left: 0;
    z-index: -1;
}

/* ── Top-left controls ────────────────────────────────────────────────────── */
.input-container {
    position: fixed;
    top: 20px;
    left: 20px;
    z-index: 10;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
}

.input-container button {
    padding: 10px 20px;
    background-color: #333;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-family: 'Heebo', sans-serif;
    transition: background-color 0.2s ease-in-out;
}

.input-container button:hover {
    background-color: #444;
}

.input-container button.recording {
    background-color: #c0392b;
}

.input-container button.recording:hover {
    background-color: #e74c3c;
}

/* ── Top-right: character set + font selectors ────────────────────────────── */
.char-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 10;
    background: rgba(20, 20, 20, 0.8);
    padding: 10px 14px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.char-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.char-row label {
    color: white;
    font-family: 'Heebo', sans-serif;
    font-size: 12px;
    white-space: nowrap;
    min-width: 70px;
}

.char-row select {
    padding: 4px 8px;
    border: none;
    border-radius: 4px;
    background: #444;
    color: white;
    font-family: 'Heebo', sans-serif;
    font-size: 12px;
    cursor: pointer;
    transition: background-color 0.2s ease-in-out;
}

.char-row select:hover {
    background: #555;
}

/* ── Sliders panel (scrolled below viewport) ──────────────────────────────── */
.slider-container {
    position: relative;
    background: rgba(20, 20, 20, 0.8);
    color: white;
    padding: 15px;
    border-radius: 10px;
    width: 80%;
    max-width: 600px;
    margin-top: 100vh;
}

.slider-container h2 {
    text-align: center;
    font-family: 'Heebo', sans-serif;
    margin-bottom: 10px;
}

.slider-group {
    margin-bottom: 15px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.slider-group div {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.slider-group label {
    font-size: 12px;
    margin-right: 10px;
    font-family: 'Heebo', sans-serif;
}

.slider-group input[type="range"] {
    width: 70%;
}

/* ── Overlay source row ───────────────────────────────────────────────────── */
.overlay-source-row {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 4px;
}

/* ── Blend mode select ────────────────────────────────────────────────────── */
#blend-mode-select {
    padding: 4px 8px;
    border: none;
    border-radius: 4px;
    background: #444;
    color: white;
    font-family: 'Heebo', sans-serif;
    font-size: 12px;
    cursor: pointer;
}

/* ── Mode buttons (Mirror / Invert / Help) ────────────────────────────────── */
.mode-btn {
    padding: 4px 12px;
    background-color: #333;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-family: 'Heebo', sans-serif;
    font-size: 12px;
    transition: background-color 0.2s ease-in-out;
}

.mode-btn:hover { background-color: #444; }
.mode-btn.active { background-color: #2980b9; }
.mode-btn.active:hover { background-color: #3498db; }

/* ── Color theme select ───────────────────────────────────────────────────── */
#color-theme-select {
    padding: 4px 8px;
    border: none;
    border-radius: 4px;
    background: #444;
    color: white;
    font-family: 'Heebo', sans-serif;
    font-size: 12px;
    cursor: pointer;
}

/* ── Keyboard shortcuts help overlay ─────────────────────────────────────── */
#help-overlay {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 20;
}

#help-overlay.hidden {
    display: none;
}

#help-box {
    background: rgba(20, 20, 20, 0.92);
    color: white;
    padding: 14px 20px;
    border-radius: 10px;
    font-family: 'Heebo', sans-serif;
    font-size: 13px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 6px 24px;
}

.help-title {
    grid-column: 1 / -1;
    font-weight: 700;
    font-size: 14px;
    margin-bottom: 4px;
    text-align: center;
    letter-spacing: 0.05em;
}

.help-row {
    display: flex;
    align-items: center;
    gap: 8px;
}

.help-key {
    display: inline-block;
    background: #555;
    border-radius: 4px;
    padding: 2px 7px;
    font-size: 11px;
    font-weight: 700;
    white-space: nowrap;
}

@media (max-width: 600px) {
    .slider-container {
        width: 95%;
    }
    .slider-group {
        grid-template-columns: 1fr;
    }
    .input-container button {
        padding: 8px 12px;
        font-size: 13px;
    }
    .char-container {
        top: auto;
        bottom: 20px;
        right: 10px;
    }
}