* {
    box-sizing: border-box;
}

#canvasContainer {
    width: 100%;
    max-width: 600px;
    aspect-ratio: 1 / 1;
    margin: 0 auto 20px auto;
    background-image:
        radial-gradient(circle, #ccc 1px, transparent 1px),
        radial-gradient(circle, #ccc 1px, transparent 1px);
    background-size: 18px 18px;
    background-position: 6px 6px;
}

[data-theme="dark"] #canvasContainer {
    background-image:
        radial-gradient(circle, #555 1px, transparent 1px),
        radial-gradient(circle, #555 1px, transparent 1px);
}

#drawingCanvas {
    width: 100%;
    height: 100%;
    display: block;
    cursor: crosshair;
    border: 1px solid var(--border-color);
    background: transparent;
    touch-action: none;
    transition: border-color 0.3s ease;
}

.toggle-caps {
    position: relative;
    width: 80px;
    height: 40px;
    cursor: grab;
    user-select: none;
}

.toggle-caps:active {
    cursor: grabbing;
}

.toggle-caps .track {
    position: absolute;
    top: 50%;
    left: 8px;
    right: 8px;
    height: 2px;
    background: #ccc;
    transform: translateY(-50%);
}

.toggle-caps .cap {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 8px;
    height: 8px;
    background: #ccc;
    border-radius: 50%;
}

.toggle-caps .cap.left {
    left: 4px;
}

.toggle-caps .cap.right {
    right: 4px;
}

.toggle-caps .knob {
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    width: 16px;
    height: 16px;
    background: var(--text-color);
    border-radius: 50%;
    transition: left 0.35s cubic-bezier(0.68, -0.3, 0.32, 1.3), background 0.35s ease;
    z-index: 1;
}

.toggle-caps.on .knob {
    left: 64px;
    background: #788a92;
}

.color-line {
    display: inline-flex;
    align-items: center;
    font-family: inherit;
    font-size: inherit;
    margin: 0;
    padding: 0;
}

.color-line .interactive {
    display: inline-flex;
    align-items: center;
    background: transparent;
    padding: 0;
    cursor: pointer;
}

.color-line .color-input {
    width: 28px;
    height: 18px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    cursor: pointer;
    padding: 0;
}

.color-line .color-input::-webkit-color-swatch-wrapper {
    padding: 0;
}

.color-line .color-input::-webkit-color-swatch {
    border: none;
    border-radius: 2px;
}

.color-line .color-input::-moz-color-swatch {
    border: none;
    border-radius: 2px;
}

.color-line .presets {
    display: inline-flex;
    gap: 6px;
    margin-left: 8px;
}

.color-line .preset {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.15s;
}

.color-line .preset:hover {
    transform: scale(1.15);
}

.color-line .preset.active {
    border-color: var(--text-color);
    box-shadow: 0 0 0 1px var(--bg-color);
}

.color-line .preset.theme-adaptive {
    background: #2b2b2c;
}

[data-theme="dark"] .color-line .preset.theme-adaptive {
    background: #f0f0f5;
}

#colorPicker {
    font-family: 'Roboto Mono', monospace;
    background: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s ease, border-color 0.3s ease;
    outline: none;
}

#colorPicker:focus {
    border-color: var(--h3-color);
}

#brushSize {
    -webkit-appearance: none;
    appearance: none;
    width: 100px;
    height: 4px;
    background: var(--border-color);
    outline: none;
    transition: background 0.3s ease;
    vertical-align: middle;
}

#brushSize::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 12px;
    height: 12px;
    background: var(--text-color);
    cursor: pointer;
    border-radius: 50%;
}

#brushSize::-moz-range-thumb {
    width: 12px;
    height: 12px;
    background: var(--text-color);
    cursor: pointer;
    border-radius: 50%;
    border: none;
}

#brushSize:focus::-webkit-slider-thumb {
    background: var(--h3-color);
}

#brushSize:focus::-moz-range-thumb {
    background: var(--h3-color);
}

#sizeDisplay {
    font-family: inherit;
    font-size: inherit;
    display: inline-block;
    text-align: right;
}

label[for="colorPicker"],
label[for="brushSize"] {
    font-family: inherit;
    font-size: inherit;
    font-weight: inherit;
    line-height: inherit;
}

#outputImage {
    width: 100%;
    height: 100%;
    display: block;
}