* { box-sizing: border-box; }
html, body {
    margin: 0; padding: 0;
    font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
    background: #14181f;
    color: #d8dde6;
    height: 100%;
}
body { display: flex; flex-direction: column; min-height: 100vh; }

.topbar {
    background: #1a2030;
    border-bottom: 1px solid #2a3447;
    padding: 8px 14px;
    display: flex; align-items: center; gap: 18px;
    flex-wrap: wrap;
}
.title { font-weight: 600; letter-spacing: 0.5px; color: #b6c2ff; }
.controls { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.controls .stat { font-size: 12px; color: #95a1b7; margin-left: 6px; }
.controls .stat span { color: #e0e7ff; font-variant-numeric: tabular-nums; }
.sim-hz-ctl { display: inline-flex; align-items: center; gap: 6px; }
.sim-hz-ctl input[type=range] { width: 110px; vertical-align: middle; }

button {
    background: #28324a;
    color: #d8dde6;
    border: 1px solid #36436a;
    border-radius: 4px;
    padding: 4px 10px;
    cursor: pointer;
    font-size: 13px;
}
button:hover { background: #344063; }
button.primary { background: #3a5cff; border-color: #4a6cff; color: white; }
button.primary:hover { background: #4a6cff; }
button.motor {
    background: #2e3a55; padding: 8px 14px;
    user-select: none;
}
button.motor:active, button.motor.held { background: #ff8a3a; color: #fff; }

.task-select {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: #9aa6c0;
    font-size: 12px;
}
.task-select select {
    background: #101622;
    color: #e8eefc;
    border: 1px solid #2b3548;
    border-radius: 4px;
    padding: 5px 8px;
}
#manual-motors {
    display: inline-flex;
    flex-wrap: wrap;
    gap: 6px;
}
.manual-row > button.motor {
    display: none;
}
body.gym-task .bug-only {
    display: none !important;
}
.gym-only {
    display: none !important;
}
body.gym-task .gym-only {
    display: flex !important;
}

select, input[type=text], input[type=number], textarea {
    background: #1f2638;
    color: #e6ecff;
    border: 1px solid #36436a;
    border-radius: 4px;
    padding: 3px 6px;
    font-size: 13px;
    font-family: inherit;
}
textarea { resize: vertical; min-height: 60px; width: 100%; }
input[type=range] { vertical-align: middle; }

.tooltip {
    position: absolute;
    background: #1a2030;
    border: 1px solid #4a5a86;
    color: #e0e7ff;
    padding: 6px 10px;
    border-radius: 4px;
    font-size: 12px;
    line-height: 1.4;
    max-width: 280px;
    white-space: pre-wrap;
    pointer-events: none;
    z-index: 1000;
    box-shadow: 0 6px 18px rgba(0,0,0,0.55);
}
.tooltip.hidden { display: none; }

.layout {
    --env-panel-width: 48%;
    display: grid;
    grid-template-columns: minmax(360px, var(--env-panel-width)) 10px minmax(420px, 1fr);
    column-gap: 0;
    padding: 10px;
    flex: 1 1 auto;
    min-height: 0;
}
.panel-resizer {
    align-self: stretch;
    cursor: col-resize;
    position: relative;
    touch-action: none;
}
.panel-resizer::before {
    content: "";
    position: absolute;
    left: 3px;
    top: 0;
    bottom: 0;
    width: 4px;
    border-radius: 999px;
    background: #283149;
}
.panel-resizer:hover::before,
.panel-resizer:focus-visible::before,
body.resizing-panels .panel-resizer::before {
    background: #4a6cff;
}
body.resizing-panels {
    cursor: col-resize;
    user-select: none;
}
.panel {
    background: #1a2030;
    border: 1px solid #283149;
    border-radius: 6px;
    display: flex; flex-direction: column;
    overflow: hidden;
}
.panel-head {
    padding: 8px 12px;
    border-bottom: 1px solid #283149;
    background: #1f2638;
    display: flex; justify-content: space-between; align-items: center;
    flex-wrap: wrap; gap: 8px;
}
.panel-head h2 {
    margin: 0; font-size: 14px; font-weight: 600;
    color: #b6c2ff; letter-spacing: 0.4px; text-transform: uppercase;
}
.panel-title-row {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 0 0 auto;
    min-width: max-content;
}
.toolbar { display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }
.toolbar label { font-size: 12px; color: #95a1b7; }

.tool-group {
    display: inline-flex;
    border-radius: 4px;
    overflow: hidden;
    border: 1px solid #36436a;
}
.tool-group .tool-btn {
    background: #1f2638;
    color: #b6c2d0;
    border: none;
    border-right: 1px solid #2a3756;
    border-radius: 0;
    padding: 5px 11px;
    font-size: 12px;
    cursor: pointer;
    transition: background 0.1s, color 0.1s;
}
.tool-group .tool-btn:last-child { border-right: none; }
.tool-group .tool-btn:hover:not(.active) { background: #2a334a; color: #e0e7ff; }
.tool-group .tool-btn.active {
    background: #3a5cff;
    color: #ffffff;
    box-shadow: inset 0 -2px 0 rgba(0,0,0,0.25);
}

/* Env panel: panel may shrink/grow, but the working ARENA is fixed-size and
   centered inside, scrollable if container is smaller. */
.env-wrap {
    background: #0d1018;
    flex: 1 1 auto;
    min-height: 0;
    overflow: auto;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6px;
}
.env-wrap canvas {
    background: #0a0d14;
    cursor: crosshair;
    display: block;
    flex: 0 0 auto;       /* preserve intrinsic pixel size */
    touch-action: none;
    border: 1px solid #2a3447;
}
.env-tools {
    padding: 8px 12px;
    border-top: 1px solid #283149;
    background: #181e2c;
    display: flex; flex-direction: column; gap: 8px;
}
.slider-row { display: flex; gap: 14px; flex-wrap: wrap; row-gap: 6px; }
.slider-row label { font-size: 12px; color: #95a1b7; display: flex; align-items: center; gap: 6px; white-space: nowrap; }
.slider-row input[type=range] { width: 110px; }
.slider-row span { color: #e0e7ff; font-variant-numeric: tabular-nums; min-width: 32px; }

.manual-row { display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }
.manual-row .hint { color: #95a1b7; font-size: 12px; margin-right: 8px; }

.net-wrap {
    display: grid;
    grid-template-columns: 1fr 230px;
    flex: 1 1 auto;
    min-height: 0;
    position: relative;   /* anchor for absolutely-positioned tooltip */
}
.net-wrap canvas {
    background: #0a0d14;
    cursor: default;
    width: 100%;
    height: 100%;
    display: block;
    touch-action: none;
}
.props {
    background: #181e2c;
    border-left: 1px solid #283149;
    padding: 10px;
    overflow-y: auto;
    font-size: 12px;
}
.props h3 {
    margin: 0 0 8px 0; font-size: 13px; color: #b6c2ff;
    text-transform: uppercase; letter-spacing: 0.5px;
}
.props-empty { color: #5b6680; font-style: italic; }
.props-form .row {
    display: flex; justify-content: space-between; align-items: center;
    gap: 6px; margin-bottom: 6px;
}
.props-form .row label { color: #95a1b7; flex: 0 0 90px; }
.props-form .row input { flex: 1 1 auto; min-width: 0; }
.props-form .row span { color: #d8dde6; font-variant-numeric: tabular-nums; }
.props-form .row.col { flex-direction: column; align-items: stretch; }
.props-form .row.col label { flex: 0 0 auto; margin-bottom: 4px; }
.props-form button { width: 100%; margin-top: 4px; }
.hidden { display: none !important; }

.legend {
    padding: 6px 12px;
    border-top: 1px solid #283149;
    background: #181e2c;
    font-size: 11px; color: #95a1b7;
    display: flex; gap: 12px; align-items: center; flex-wrap: wrap;
}
.legend .dot {
    display: inline-block;
    width: 10px; height: 10px;
    border-radius: 50%;
    margin-right: 4px;
    vertical-align: middle;
}
.legend .dot.sensor { background: #34d2ff; }
.legend .dot.motor  { background: #ff8a3a; }
.legend .dot.inter  { background: #9be37c; }
.legend .hint { color: #5b6680; margin-left: auto; font-style: italic; }

dialog {
    background: #1a2030; color: #d8dde6;
    border: 1px solid #36436a; border-radius: 6px;
    padding: 16px 20px;
}
dialog::backdrop { background: rgba(10, 14, 22, 0.75); }
dialog h3 { margin: 0 0 10px 0; color: #b6c2ff; font-size: 14px; }
dialog menu { display: flex; justify-content: flex-end; gap: 8px; padding: 0; margin: 12px 0 0 0; }
#load-list { list-style: none; padding: 0; margin: 0; max-height: 240px; overflow-y: auto; }
#load-list li {
    padding: 6px 10px; cursor: pointer; border-radius: 4px;
}
#load-list li:hover { background: #2a3550; }
#load-list .load-section {
    color: #7aa0ff;
    cursor: default;
    font-weight: 700;
    margin-top: 8px;
}
#load-list .load-section:hover { background: transparent; }