/* CSS Reset & Base */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-dark: #0a0a0a;
    --bg-sidebar: #111115;
    --bg-control: #1a1a20;
    --text-primary: #ffffff;
    --text-secondary: #888899;
    --accent-purple: #bf5af2;
    --accent-cyan: #64ffda;
    --sidebar-width: 280px;
    --transition-speed: 0.3s;
}

html, body {
    height: 100%;
    overflow: hidden;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
}

/* Sidebar */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: var(--bg-sidebar);
    border-right: 1px solid rgba(255, 255, 255, 0.08);
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: transform var(--transition-speed) ease;
}

.sidebar-header {
    padding: 24px 20px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.sidebar-header h1 {
    font-size: 1.4rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* Controls */
.controls {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
}

.control-group {
    margin-bottom: 24px;
}

.control-group label {
    display: block;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 8px;
    font-weight: 500;
}

/* Select Dropdowns */
select {
    width: 100%;
    padding: 12px 14px;
    background: var(--bg-control);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.95rem;
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23888899' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

select:hover, select:focus {
    border-color: var(--accent-purple);
    outline: none;
    box-shadow: 0 0 0 3px rgba(191, 90, 242, 0.15);
}

/* Range Sliders */
input[type="range"] {
    width: 100%;
    height: 6px;
    background: var(--bg-control);
    border-radius: 3px;
    appearance: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    appearance: none;
    width: 18px;
    height: 18px;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-cyan));
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(191, 90, 242, 0.4);
    transition: transform 0.15s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
}

input[type="range"]::-moz-range-thumb {
    width: 18px;
    height: 18px;
    background: linear-gradient(135deg, var(--accent-purple), var(--accent-cyan));
    border-radius: 50%;
    border: none;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(191, 90, 242, 0.4);
}

/* Buttons */
.button-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 32px;
}

.btn {
    width: 100%;
    padding: 14px 20px;
    border: none;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all var(--transition-speed) ease;
}

.btn-icon {
    font-size: 1.1rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-purple), #9b4dca);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(191, 90, 242, 0.4);
}

.btn-secondary {
    background: var(--bg-control);
    color: var(--text-primary);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.btn-secondary:hover {
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
}

.btn:active {
    transform: translateY(0);
}

/* Sidebar Footer */
.sidebar-footer {
    padding: 16px 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    text-align: center;
}

.sidebar-footer p {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

/* Canvas Container */
#canvas-container {
    position: fixed;
    top: 0;
    left: var(--sidebar-width);
    right: 0;
    bottom: 0;
    background: var(--bg-dark);
    touch-action: none;
}

#canvas-container canvas {
    display: block;
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: none;
    position: fixed;
    top: 16px;
    left: 16px;
    width: 48px;
    height: 48px;
    background: var(--bg-sidebar);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    cursor: pointer;
    z-index: 200;
    align-items: center;
    justify-content: center;
}

.hamburger {
    width: 22px;
    height: 2px;
    background: var(--text-primary);
    position: relative;
    transition: background var(--transition-speed);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 22px;
    height: 2px;
    background: var(--text-primary);
    transition: transform var(--transition-speed);
}

.hamburger::before {
    top: -7px;
}

.hamburger::after {
    top: 7px;
}

/* Menu open state */
.menu-toggle.active .hamburger {
    background: transparent;
}

.menu-toggle.active .hamburger::before {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active .hamburger::after {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Overlay */
.overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 50;
    opacity: 0;
    transition: opacity var(--transition-speed);
}

.overlay.active {
    display: block;
    opacity: 1;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    :root {
        --sidebar-width: 280px;
    }

    .menu-toggle {
        display: flex;
    }

    .sidebar {
        transform: translateX(-100%);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    #canvas-container {
        left: 0;
    }

    .controls {
        padding: 16px;
    }

    .control-group {
        margin-bottom: 20px;
    }
}

/* Touch-friendly on mobile */
@media (hover: none) and (pointer: coarse) {
    select,
    .btn {
        padding: 16px;
        font-size: 1rem;
    }

    input[type="range"]::-webkit-slider-thumb {
        width: 24px;
        height: 24px;
    }

    input[type="range"]::-moz-range-thumb {
        width: 24px;
        height: 24px;
    }
}

/* Smooth scrollbar for controls */
.controls::-webkit-scrollbar {
    width: 6px;
}

.controls::-webkit-scrollbar-track {
    background: transparent;
}

.controls::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 3px;
}

.controls::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.2);
}