/* ============================================================
   AGC 功率控制策略可视化 · 样式表（合并版）
   水电站自动化课程 · 5.1 信号元件
   ============================================================ */

:root {
  --ink:   #0a100e;
  --panel2:#0f1815;
  --line:  rgba(132,172,152,.18);
  --line2: rgba(132,172,152,.08);
  --text:  #dfe9e4;
  --dim:   #86998f;
  --dim2:  #5d7268;
  --amber: #e9a13b;
  --teal:  #48c9bd;
  --mono:  ui-monospace, "SF Mono", Consolas, "Courier New", monospace;
}

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

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", sans-serif;
  background: var(--ink);
  color: var(--text);
  min-height: 100vh;
  padding: 24px 18px 40px;
  display: flex;
  flex-direction: column;
  align-items: center;
  -webkit-font-smoothing: antialiased;
  -webkit-text-size-adjust: 100%;
}

.wrap { width: 100%; max-width: 1200px; }

/* ── 页头 ── */
.head { margin-bottom: 22px; }

.tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--teal);
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.tag::before {
  content: "";
  width: 24px; height: 1px;
  background: var(--teal);
  opacity: .7;
}

h1 {
  font-size: clamp(20px, 3.4vw, 30px);
  line-height: 1.24;
  font-weight: 700;
  letter-spacing: -.01em;
  margin-bottom: 8px;
}

h1 em { font-style: normal; color: var(--amber); }

.sub { font-size: 14px; color: var(--dim); line-height: 1.8; }

/* ── 标签页切换 ── */
.tabs {
  display: flex;
  gap: 1px;
  background: var(--line2);
  border: 1px solid var(--line);
  border-bottom: none;
  margin-bottom: 0;
}

.tab {
  flex: 1;
  background: var(--panel2);
  border: none;
  padding: 12px 16px;
  cursor: pointer;
  font-family: "Microsoft YaHei", sans-serif;
  font-size: 13px;
  color: var(--dim);
  display: flex;
  align-items: center;
  gap: 10px;
  transition: background .15s, color .15s;
  position: relative;
}

.tab:hover {
  background: rgba(132,172,152,.06);
  color: var(--text);
}

.tab.active {
  background: var(--ink);
  color: var(--text);
}

.tab.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--teal);
}

.tab .tn {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--teal);
  letter-spacing: .08em;
  flex-shrink: 0;
}

.tab .tm {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--dim2);
  margin-left: auto;
}

@media (max-width: 600px) {
  .tabs { flex-direction: column; }
  .tab .tm { display: none; }
}

/* ── 面板视图 ── */
.panel-view {
  display: none;
  animation: fadeIn .3s ease;
}

.panel-view.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── 播放器 ── */
.player {
  border: 1px solid var(--line);
  border-top: none;
  background: #080f0d;
  position: relative;
  overflow: hidden;
  margin-bottom: 20px;
}

.player video {
  display: block;
  width: 100%;
  height: auto;
  background: #000;
}

.player::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  box-shadow: inset 0 0 90px rgba(0,0,0,.55);
}

/* ── iframe 演示 ── */
.frame-hint {
  border: 1px solid var(--line);
  border-top: none;
  background: var(--panel2);
  padding: 11px 15px;
  font-size: 13px;
  color: var(--dim);
  line-height: 1.7;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.frame-hint a {
  color: var(--teal);
  text-decoration: none;
  font-family: var(--mono);
  font-size: 12px;
}

.frame-hint a:hover {
  text-decoration: underline;
}

.demo-frame {
  display: block;
  width: 100%;
  height: clamp(600px, 80vh, 900px);
  border: 1px solid var(--line);
  border-top: none;
  background: var(--ink);
  margin-bottom: 20px;
}

/* ── 面板 ── */
.panel {
  border: 1px solid var(--line);
  background: var(--panel2);
  margin-bottom: 18px;
}

.panel > h2 {
  font-size: 14px;
  font-weight: 500;
  padding: 11px 15px;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: center;
  gap: 9px;
}

.panel > h2::before {
  content: "";
  width: 6px; height: 6px;
  background: var(--amber);
  flex: 0 0 auto;
}

.panel.t > h2::before { background: var(--teal); }

/* ── 参数网格 ── */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1px;
  background: var(--line2);
}

.cell { background: var(--panel2); padding: 12px 15px; }

.cell .k {
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--dim2);
  margin-bottom: 5px;
}

.cell .v {
  font-family: var(--mono);
  font-size: 16px;
  color: var(--text);
  font-feature-settings: 'tnum';
}

.cell .v small { font-size: 11px; color: var(--dim2); margin-left: 3px; }

/* ── 分镜列表 ── */
.shots { list-style: none; }

.shots li {
  display: flex;
  gap: 14px;
  padding: 11px 15px;
  border-bottom: 1px solid var(--line2);
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--dim);
}

.shots li:last-child { border-bottom: none; }

.shots .no {
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--amber);
  flex: 0 0 52px;
  padding-top: 2px;
}

.shots li strong { color: var(--text); font-weight: 500; }

.shots .ref { font-family: var(--mono); font-size: 11px; color: var(--dim2); }

/* ── 说明 ── */
.notes { padding: 14px 15px; }

.notes p {
  font-size: 13.5px;
  color: var(--dim);
  line-height: 1.85;
  margin-bottom: 8px;
}

.notes p:last-child { margin-bottom: 0; }
.notes p strong { color: var(--text); font-weight: 500; }

.notes .hl { color: var(--teal); font-family: var(--mono); font-size: 12.5px; }

/* ── 页脚 ── */
.foot {
  border-top: 1px solid var(--line2);
  padding-top: 16px;
  margin-top: 20px;
  font-family: var(--mono);
  font-size: 11px;
  color: var(--dim2);
  line-height: 1.9;
  letter-spacing: .03em;
}

/* ── 移动端 ── */
@media (max-width: 600px) {
  body { padding: 16px 12px 30px; }
  .shots li { flex-direction: column; gap: 3px; }
  .shots .no { flex: none; }
  .grid { grid-template-columns: repeat(2, 1fr); }
  .demo-frame { height: 500px; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: .001ms !important; transition-duration: .001ms !important; }
  .panel-view { animation: none; }
}