:root {
    --primary: #ff8a00;
    --secondary: #e52e71;
    --bg: #0f0f1a;
    --glass: rgba(255, 255, 255, 0.05);
    --glass-heavy: rgba(15, 15, 26, 0.85);
}

/* Base Styles & Centering */
body { 
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif; 
    background: radial-gradient(circle at center, #1a1a2e 0%, var(--bg) 100%);
    color: white; 
    display: flex; 
    flex-direction: column; 
    align-items: center; 
    justify-content: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    box-sizing: border-box;
}

/* Main App Container */
.container { 
    background: var(--glass); 
    padding: 30px; 
    border-radius: 24px; 
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(12px);
    box-shadow: 0 20px 50px rgba(0,0,0,0.5);
    text-align: center; 
    max-width: 550px;
    width: 100%;
    margin-bottom: 20px; /* Space for sidebar on mobile */
}

h1 {
    margin: 0 0 20px 0;
    background: linear-gradient(to right, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 2.2rem;
    font-weight: 800;
}

.section-label {
    display: block;
    margin: 20px 0 10px;
    font-size: 0.75rem;
    color: rgba(255,255,255,0.5);
    text-transform: uppercase;
    letter-spacing: 1.5px;
    font-weight: bold;
}

/* Buttons & Grids */
.button-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(85px, 1fr));
    gap: 8px;
    margin-bottom: 15px;
}

#waveSelectors {
    grid-template-columns: repeat(4, 1fr);
}

#waveSelectors .lock-btn {
    grid-column: span 4;
    padding: 8px;
    margin-top: 5px;
}

button { 
    padding: 10px; 
    border-radius: 10px; 
    border: 1px solid rgba(255,255,255,0.1);
    background: rgba(255,255,255,0.07);
    color: white; 
    cursor: pointer; 
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    font-size: 0.9rem;
}

button:hover { 
    background: rgba(255,255,255,0.15); 
    transform: translateY(-1px); 
}

button.active { 
    background: var(--primary); 
    border-color: var(--primary);
    box-shadow: 0 0 15px rgba(255, 138, 0, 0.3);
}

/* Controls Section */
.controls { 
    background: rgba(0,0,0,0.25);
    padding: 20px;
    border-radius: 18px;
    margin-bottom: 25px;
}

.control-group { 
    display: flex; 
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.control-header label {
    font-size: 0.85rem;
    width: 50px;
    text-align: left;
}

input[type=range] { 
    flex: 1; 
    accent-color: var(--primary);
    height: 6px;
    cursor: pointer;
}

/* ADSR Layout */
.adsr-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.adsr-grid .control-group {
    margin-bottom: 0;
}

/* Main Play/Save Actions */
.main-actions {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.btn-play { 
    grid-column: span 2;
    background: linear-gradient(135deg, #00c9ff, #007bff); 
    font-weight: bold;
    font-size: 1.1rem;
    padding: 15px;
}

.btn-download, .btn-save, .btn-load {
    font-weight: 600;
    font-size: 0.85rem;
}

.btn-download { background: linear-gradient(135deg, var(--primary), var(--secondary)); }
.btn-save { background: #333; }
.btn-load { background: #333; }

/* Visualizer */
.visualizer-container {
    width: 100%;
    height: 80px;
    background: #000;
    border-radius: 12px;
    margin-bottom: 15px;
    border: 1px solid rgba(255,255,255,0.05);
}

canvas {
    width: 100%;
    height: 100%;
}

/* Lock Button */
.lock-btn {
    background: none;
    border: none;
    color: rgba(255,255,255,0.3);
    font-size: 1rem;
    padding: 4px;
}

.lock-btn.locked { color: var(--primary); }

/* SIDEBAR: Bottom Right Floating */
.presets-sidebar {
    position: fixed;
    right: 20px;
    bottom: 20px;
    width: 280px;
    max-height: 300px;
    background: var(--glass-heavy);
    border-radius: 20px;
    padding: 18px;
    border: 1px solid rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.6);
    z-index: 1000;
    overflow-y: auto;
}

.presets-sidebar h3 {
    margin-top: 0;
    font-size: 1rem;
    color: var(--primary);
    border-bottom: 1px solid rgba(255,255,255,0.1);
    padding-bottom: 10px;
    margin-bottom: 12px;
}

.preset-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(255,255,255,0.05);
    padding: 8px 10px;
    border-radius: 8px;
    margin-bottom: 8px;
}

.btn-load-preset {
    background: none;
    border: none;
    color: #eee;
    font-size: 0.85rem;
    text-align: left;
    padding: 0;
}

.btn-delete-preset {
    background: rgba(255, 50, 50, 0.2);
    color: #ff8888;
    padding: 4px 8px;
    font-size: 0.7rem;
}

/* Scrollbar Style */
.presets-sidebar::-webkit-scrollbar { width: 5px; }
.presets-sidebar::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.2); border-radius: 10px; }

/* Responsive Adjustments */
@media (max-width: 768px) {
    .container {
        padding: 20px;
        margin-top: 20px;
    }
    
    .presets-sidebar {
        position: relative; /* Moves under content */
        right: 0;
        bottom: 0;
        width: 100%;
        max-width: 550px;
        max-height: none;
        box-sizing: border-box;
    }
}

@media (max-width: 400px) {
    h1 { font-size: 1.6rem; }
    .main-actions { grid-template-columns: 1fr; }
    #waveSelectors { grid-template-columns: repeat(2, 1fr); }
}