/* 实验四 公共样式：固定观察/投影由 engine.js 提供，此处仅负责页面布局与控件外观。 */
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;
  background: #f3f7fa;
  color: #1f3244;
  line-height: 1.6;
}
header .top {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 24px;
  background: #1f4d6b;
  color: #fff;
}
header .brand { font-weight: 700; font-size: 17px; }
header .tag {
  font-size: 13px;
  background: rgba(255,255,255,.18);
  padding: 2px 10px;
  border-radius: 12px;
}
header .back { margin-left: auto; color: #dceaf3; text-decoration: none; font-size: 14px; }
header .back:hover { text-decoration: underline; }
main { max-width: 1180px; margin: 0 auto; padding: 24px; }
h1 { font-size: 24px; margin: 8px 0; }
h2 { font-size: 16px; margin: 0 0 12px; }
.lead { color: #4a6274; font-size: 15px; margin: 6px 0 18px; }
.value { font-variant-numeric: tabular-nums; color: #1f6f8b; font-weight: 600; }

/* 首页卡片 */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 16px; margin: 18px 0; }
.card {
  display: block;
  text-decoration: none;
  color: inherit;
  background: #fff;
  border: 1px solid #d7e3ec;
  border-radius: 10px;
  padding: 16px;
  transition: transform .15s, box-shadow .15s;
}
.card:hover { transform: translateY(-3px); box-shadow: 0 6px 18px rgba(31,77,107,.12); }
.card strong { display: block; font-size: 16px; margin-bottom: 6px; color: #1f4d6b; }
.card p { margin: 0; font-size: 13px; color: #5b7283; }

/* 任务页两栏布局 */
.layout { display: grid; grid-template-columns: 1fr 320px; gap: 18px; margin-top: 8px; }
.stage { background: #fff; border: 1px solid #d7e3ec; border-radius: 10px; padding: 14px; }
.canvas-wrap { width: 100%; }
#gl-canvas { width: 100%; height: auto; display: block; border-radius: 6px; background: #f6fafd; }
.status {
  margin: 10px 0;
  padding: 8px 12px;
  background: #eef5f9;
  border-left: 3px solid #1f6f8b;
  border-radius: 4px;
  font-size: 13px;
}
.tip { font-size: 13px; color: #5b7283; margin: 8px 0 0; }

.panel { background: #fff; border: 1px solid #d7e3ec; border-radius: 10px; padding: 16px; }
.panel label { display: block; font-size: 14px; margin: 10px 0 4px; }
.panel input[type="range"], .panel input[type="number"] {
  width: 100%;
  padding: 5px 8px;
  border: 1px solid #c6d6e1;
  border-radius: 6px;
  font-size: 14px;
}
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.buttons { margin-top: 16px; display: flex; flex-wrap: wrap; gap: 10px; }
button {
  padding: 8px 14px;
  border: none;
  border-radius: 6px;
  background: #1f6f8b;
  color: #fff;
  font-size: 14px;
  cursor: pointer;
}
button.alt { background: #5b8aa5; }
button:hover { filter: brightness(1.08); }

.info {
  margin-top: 18px;
  background: #fff;
  border: 1px dashed #c6d6e1;
  border-radius: 10px;
  padding: 14px 18px;
  font-size: 14px;
}
.info ul { margin: 8px 0 0 18px; padding: 0; }
.info code { background: #eef5f9; padding: 1px 6px; border-radius: 4px; font-size: 13px; }
.notes { font-size: 13px; color: #5b7283; margin-top: 18px; }

@media (max-width: 880px) {
  .layout { grid-template-columns: 1fr; }
  main { padding: 16px; }
}