html, body {
    margin: 0;
    height: 100%;
    background: #1b2030;
    overflow: hidden;
    font-family: "Segoe UI", system-ui, sans-serif;
    color: #e8edf6;
}

.layout {
    position: fixed;
    inset: 0;
}

#board-canvas {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
    touch-action: none;
}

.panel {
    position: fixed;
    top: 12px;
    left: 12px;
    z-index: 10;
    min-width: 220px;
    max-height: calc(100vh - 24px);
    overflow-y: auto;
    padding: 12px 14px;
    background: rgba(20, 26, 40, 0.86);
    border: 1px solid #33405c;
    border-radius: 10px;
    backdrop-filter: blur(6px);
    box-shadow: 0 6px 24px rgba(0, 0, 0, 0.4);
}

.panel h1 {
    font-size: 13px;
    margin: 0 0 8px;
    font-weight: 600;
    letter-spacing: 0.3px;
    color: #9fb4d8;
}

.panel select {
    width: 100%;
    padding: 6px;
    margin-bottom: 8px;
    background: #26314a;
    color: #e8edf6;
    border: 1px solid #3b4a69;
    border-radius: 6px;
}

.status {
    font-size: 11px;
    color: #6b7da0;
    margin: 4px 0 6px;
}

.sec {
    margin-top: 8px;
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.6px;
    color: #6b7da0;
}

.row {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 2px 0;
    font-size: 13px;
    cursor: pointer;
    user-select: none;
}

.row input {
    accent-color: #5b8def;
    width: 14px;
    height: 14px;
}

.hint {
    position: fixed;
    bottom: 10px;
    left: 0;
    width: 100%;
    text-align: center;
    font-size: 12px;
    color: #6b7da0;
    pointer-events: none;
}