/* Base Reset & Variables scoped to wrapper */
#billy-notes-wrapper {
    --billy-orange: #F5A623; 
    --billy-dark: #333; 
    --billy-blue: #008080; 
    --bg-light: #f9f9f9; 
    --slate-200: #e2e8f0;
    --slate-400: #94a3b8;
    --slate-500: #64748b;
    --slate-800: #1e293b;
    
    line-height: 1.6; 
    color: #333; 
    width: 100%; 
    max-width: 800px;
    margin: 0 auto; 
    background: #fff;
    font-family: 'Segoe UI', 'Microsoft JhengHei', sans-serif;
    -webkit-font-smoothing: antialiased;
    box-sizing: border-box;
}

#billy-notes-wrapper * { 
    box-sizing: border-box; 
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

#billy-notes-wrapper .zh-text { color: #666; font-size: 0.9em; display: block; margin-top: 4px; font-weight: normal; }

/* Cards & Layout */
#billy-notes-wrapper .note-card { 
    background: var(--bg-light); 
    border-radius: 12px; 
    padding: 0; 
    margin: 20px 0; 
    box-shadow: 0 4px 15px rgba(0,0,0,0.05); 
    border-top: 4px solid var(--billy-blue); 
    overflow: hidden;
}

#billy-notes-wrapper .card-header {
    padding: 20px 25px;
    border-bottom: 1px solid var(--slate-200);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: #fff;
    gap: 15px;
}

/* Status Badge */
#billy-notes-wrapper .status-badge {
    padding: 6px 24px;
    border-radius: 9999px;
    font-size: 0.85rem;
    font-weight: 700;
    text-align: center;
    border: 1px solid transparent;
    transition: all 0.3s ease;
}
#billy-notes-wrapper .status-running { background: #fee2e2; color: #b91c1c; border-color: #fecaca; animation: pulse 2s infinite; }
#billy-notes-wrapper .status-paused { background: #f1f5f9; color: var(--slate-500); border-color: var(--slate-200); }

/* Pressure Display */
#billy-notes-wrapper .pressure-display {
    text-align: center;
    width: 100%;
    padding: 15px;
    background: var(--bg-light);
    border-radius: 8px;
    border: 1px solid var(--slate-200);
    position: relative;
    overflow: hidden;
}
#billy-notes-wrapper .pressure-display::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; height: 4px;
    background: linear-gradient(90deg, var(--billy-blue), var(--billy-orange));
}
#billy-notes-wrapper .pressure-val {
    font-size: 3.5rem;
    font-family: monospace;
    font-weight: bold;
    color: var(--slate-800);
    line-height: 1.1;
}
#billy-notes-wrapper .pressure-unit { font-size: 1.2rem; color: var(--slate-500); font-weight: bold; }

/* Diagram Area */
#billy-notes-wrapper .diagram-container {
    position: relative;
    width: 100%;
    background: #0f172a;
    border-bottom: 1px solid var(--slate-200);
    padding: 0;
    margin: 0;
    line-height: 0;
    aspect-ratio: 16/7;
    overflow: hidden;
}
#billy-notes-wrapper canvas#simCanvas {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: contain;
    image-rendering: pixelated;
}
#billy-notes-wrapper .overlay-info {
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(0,0,0,0.6);
    color: white;
    padding: 5px 10px;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85rem;
    pointer-events: none;
    margin: 0;
}

/* Sliders */
#billy-notes-wrapper .sliders-wrapper {
    padding: 25px;
    background: #fff;
    border-bottom: 1px solid var(--slate-200);
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 20px;
}
#billy-notes-wrapper .slider-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
#billy-notes-wrapper .slider-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: bold;
    font-size: 0.9rem;
    color: var(--slate-800);
}
#billy-notes-wrapper .val-badge {
    background: var(--bg-light);
    border: 1px solid var(--slate-200);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85rem;
}
#billy-notes-wrapper .val-badge.temp { color: #ef4444; border-color: #fecaca; background: #fef2f2; }
#billy-notes-wrapper .val-badge.vol { color: #3b82f6; border-color: #bfdbfe; background: #eff6ff; }
#billy-notes-wrapper .val-badge.mol { color: #8b5cf6; border-color: #ddd6fe; background: #f5f3ff; }

#billy-notes-wrapper input[type=range] {
    -webkit-appearance: none; 
    width: 100%; 
    background: transparent; 
}
#billy-notes-wrapper input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 18px;
    width: 18px;
    border-radius: 50%;
    background: var(--billy-blue);
    cursor: pointer;
    margin-top: -6px; 
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    border: 2px solid white;
}
#billy-notes-wrapper .slider-temp::-webkit-slider-thumb { background: #ef4444 !important; }
#billy-notes-wrapper .slider-vol::-webkit-slider-thumb { background: #3b82f6 !important; }
#billy-notes-wrapper .slider-mol::-webkit-slider-thumb { background: #8b5cf6 !important; }

#billy-notes-wrapper input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 6px;
    cursor: pointer;
    background: var(--slate-200);
    border-radius: 3px;
}

/* Controls */
#billy-notes-wrapper .controls {
    padding: 25px;
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 20px;
    background: #fff;
}

#billy-notes-wrapper button {
    padding: 15px;
    border-radius: 12px;
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
}

#billy-notes-wrapper .btn-start {
    background: linear-gradient(135deg, #F5A623 0%, #F76B1C 100%);
    color: white;
    box-shadow: 0 4px 10px rgba(245, 166, 35, 0.3);
}
#billy-notes-wrapper .btn-start.paused {
    background: linear-gradient(135deg, #22c55e 0%, #16a34a 100%);
    box-shadow: 0 4px 10px rgba(34, 197, 94, 0.3);
}
#billy-notes-wrapper .btn-start:hover { transform: translateY(-2px); box-shadow: 0 6px 15px rgba(0, 0, 0, 0.15); }
#billy-notes-wrapper .btn-start:active { transform: scale(0.98); }
#billy-notes-wrapper .btn-start .zh-text { color: rgba(255,255,255,0.9); margin-top: 0; }

#billy-notes-wrapper .btn-reset {
    background: white;
    border: 2px solid var(--billy-blue);
    color: var(--billy-blue);
}
#billy-notes-wrapper .btn-reset:hover { background: #f0f8f8; transform: translateY(-2px); }
#billy-notes-wrapper .btn-reset:active { transform: scale(0.98); }
#billy-notes-wrapper .btn-reset .zh-text { color: var(--billy-blue); margin-top: 0; }

/* Animations */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

/* Mobile Optimization */
@media (max-width: 600px) {
    #billy-notes-wrapper .card-header { padding: 15px; }
    #billy-notes-wrapper .sliders-wrapper { grid-template-columns: 1fr; gap: 15px; padding: 20px; }
    #billy-notes-wrapper .controls { grid-template-columns: 1fr; gap: 15px; padding: 20px; }
    #billy-notes-wrapper .pressure-val { font-size: 2.5rem; }
    #billy-notes-wrapper .diagram-container { aspect-ratio: 4/3; }
}