:root {
  --bg: #0f1115;
  --panel: #171a21;
  --panel-2: #1e222b;
  --border: #2a2f3a;
  --text: #e6e9ef;
  --muted: #8b93a3;
  --accent: #3b82f6;
  --accent-2: #22c55e;
  --warn: #f59e0b;
  --danger: #ef4444;
  --radius: 12px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

/* ===== 顶栏 ===== */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 22px;
  background: linear-gradient(180deg, #1a1e27, #14171e);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.brand h1 { margin: 0; font-size: 18px; letter-spacing: 0.5px; }
.subtitle { color: var(--muted); font-size: 12px; }

.conn { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.status { display: flex; align-items: center; gap: 8px; font-size: 14px; }
.port-info { color: var(--muted); font-size: 12px; }

.dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--danger);
  box-shadow: 0 0 6px currentColor;
}
.dot.on { background: var(--accent-2); color: var(--accent-2); }
.dot.off { background: var(--danger); color: var(--danger); }
.dot.connecting { background: var(--warn); color: var(--warn); animation: pulse 1s infinite; }
@keyframes pulse { 50% { opacity: 0.35; } }

.baud-label { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--muted); }
select, .btn {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 12px;
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
  transition: 0.15s;
}
select:focus, .btn:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.btn:hover { border-color: var(--accent); background: #232834; }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 600; }
.btn.primary:hover { background: #2f6fe0; }
.btn.small { padding: 4px 10px; font-size: 12px; }

/* ===== 主体 ===== */
main { padding: 18px 22px 40px; max-width: 1100px; margin: 0 auto; }

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 18px;
  margin-bottom: 16px;
}
.card-head {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 12px; margin-bottom: 14px; flex-wrap: wrap;
}
.card-head h2 { margin: 0; font-size: 15px; }
.hint { color: var(--muted); font-size: 12px; }

/* 伺服电机 */
.motor-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
  margin-bottom: 14px;
}
.motor-card {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
}
.motor-card h3 { margin: 0 0 8px; font-size: 15px; }
.motor-card small { color: var(--muted); font-weight: 400; }
.pos {
  font-size: 22px; font-weight: 700; color: var(--accent);
  margin-bottom: 12px; font-variant-numeric: tabular-nums;
}
.pos small { font-size: 12px; color: var(--muted); font-weight: 400; }
.btn-row { display: flex; gap: 8px; }
.btn-row .btn { flex: 1; }
.btn.fwd { background: #1c3a2a; border-color: #2f6e4a; color: #7ee0a8; }
.btn.fwd:hover { background: #234632; }
.btn.back { background: #3a2828; border-color: #6e3f3f; color: #e0a8a8; }
.btn.back:hover { background: #46302f; }
.btn.home {
  width: 100%; padding: 12px; font-size: 15px; font-weight: 600;
  background: #2a2a4a; border-color: #4a4a8e; color: #b3b3f0;
}
.btn.home:hover { background: #323266; }

/* 日志 */
.log-actions { display: flex; gap: 8px; }
.log {
  background: #0c0e12;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
  height: 180px;
  overflow-y: auto;
  font-family: "Cascadia Code", Consolas, monospace;
  font-size: 12.5px;
}
.log-line { padding: 2px 0; color: var(--text); }
.log-line.sys { color: var(--muted); }
.log-line.fail { color: var(--danger); }

/* 提示条 */
.warn {
  margin: 12px 22px;
  padding: 10px 14px;
  background: rgba(245,158,11,0.12);
  border: 1px solid var(--warn);
  border-radius: 8px;
  color: var(--warn);
  font-size: 13px;
}
.hidden { display: none !important; }

/* Toast */
.toast {
  position: fixed; left: 50%; bottom: 28px;
  transform: translateX(-50%);
  background: #232834; border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 18px; border-radius: 8px;
  font-size: 13px; box-shadow: 0 6px 20px rgba(0,0,0,0.4);
  z-index: 99;
}
.toast.error { border-color: var(--danger); color: #ffb4b4; }