* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: #f0e6d0;
    display: flex;
    justify-content: center;
    min-height: 100vh;
    padding: 20px;
}

#app {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

h1 {
    font-size: 24px;
    color: #4a3520;
}

#controls {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
    justify-content: center;
}

#controls button {
    padding: 6px 16px;
    border: 1px solid #8b7355;
    border-radius: 4px;
    background: #d4c4a8;
    color: #4a3520;
    cursor: pointer;
    font-size: 14px;
}

#controls button:hover {
    background: #c4b498;
}

#controls button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

#controls label {
    font-size: 14px;
    color: #4a3520;
}

#controls select {
    padding: 4px 8px;
    border: 1px solid #8b7355;
    border-radius: 4px;
    background: #fff;
    font-size: 14px;
}

#board-container {
    border: 3px solid #8b7355;
    border-radius: 4px;
    background: #e8c97a;
}

canvas {
    display: block;
    cursor: pointer;
}

#status-bar {
    font-size: 16px;
    color: #4a3520;
    min-height: 24px;
}

.thinking #status-text::after {
    content: '';
    display: inline-block;
    width: 12px;
    animation: dots 1.5s steps(4, end) infinite;
}

@keyframes dots {
    0%   { content: ''; }
    25%  { content: '.'; }
    50%  { content: '..'; }
    75%  { content: '...'; }
}

/* Difficulty controls */
#difficulty-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

#preset-bar {
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
    justify-content: center;
}

.preset-btn {
    padding: 5px 12px;
    border: 1px solid #8b7355;
    border-radius: 4px;
    background: #d4c4a8;
    color: #4a3520;
    cursor: pointer;
    font-size: 13px;
    transition: background 0.15s, color 0.15s;
}

.preset-btn:hover {
    background: #c4b498;
}

.preset-btn.active {
    background: #4a3520;
    color: #f0e6d0;
    border-color: #4a3520;
}

.preset-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

#custom-panel {
    background: #e8dcc6;
    border: 1px solid #8b7355;
    border-radius: 4px;
    padding: 10px 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    min-width: 280px;
}

#custom-panel.hidden {
    display: none;
}

.slider-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.slider-row label {
    font-size: 13px;
    color: #4a3520;
    white-space: nowrap;
    min-width: 110px;
}

.slider-row input[type="range"] {
    flex: 1;
    accent-color: #8b7355;
}

.slider-hint {
    font-size: 12px;
    color: #8b7355;
    text-align: center;
}