/* 引入现代教育学专用字体 */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Outfit:wght@400;600;700;800&display=swap');

:root {
  --bg-main: #0B0F19;
  --bg-sidebar: #111827;
  --bg-panel: rgba(17, 24, 39, 0.7);
  --border-color: rgba(255, 255, 255, 0.08);
  --text-main: #F3F4F6;
  --text-muted: #9CA3AF;
  --accent-color: #0284C7;
  --accent-glow: rgba(2, 132, 199, 0.4);
  --success: #10B981;
  --danger: #EF4444;
  --warning: #F59E0B;
}

[data-theme="light"] {
  --bg-main: #F8FAFC;
  --bg-sidebar: #FFFFFF;
  --bg-panel: rgba(255, 255, 255, 0.85);
  --border-color: rgba(0, 0, 0, 0.08);
  --text-main: #0F172A;
  --text-muted: #475569;
  --accent-color: #0284C7;
  --accent-glow: rgba(2, 132, 199, 0.25);
  --success: #059669;
  --danger: #DC2626;
  --warning: #D97706;
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg-main);
  color: var(--text-main);
  height: 100vh;
  overflow: hidden;
  display: flex;
}

/* 主结构：侧边栏 + 工作区 */
.app-container {
  display: flex;
  width: 100%;
  height: 100%;
}

/* 侧边栏：章节选择 */
.sidebar {
  width: 280px;
  background-color: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  height: 100%;
}

.logo-container {
  padding: 24px 20px;
  border-bottom: 1px solid var(--border-color);
}

.logo-title {
  font-family: 'Outfit', sans-serif;
  font-size: 18px;
  font-weight: 700;
  color: var(--accent-color);
  text-shadow: 0 0 10px var(--accent-glow);
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-sub {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 4px;
}

.chapter-list {
  flex: 1;
  overflow-y: auto;
  padding: 16px 12px;
  list-style: none;
}

.chapter-item {
  margin-bottom: 8px;
}

.chapter-header {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  padding: 8px 12px;
  letter-spacing: 0.05em;
}

.chapter-btn {
  width: 100%;
  display: flex;
  align-items: center;
  padding: 12px;
  background: none;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--text-main);
  font-size: 13.5px;
  text-align: left;
  cursor: pointer;
  transition: all 0.2s ease;
  gap: 10px;
}

.chapter-btn:hover {
  background-color: rgba(2, 132, 199, 0.08);
  color: var(--accent-color);
}

.chapter-btn.active {
  background-color: var(--accent-color);
  color: #FFFFFF;
  font-weight: 600;
  box-shadow: 0 4px 12px var(--accent-glow);
}

.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.theme-toggle-btn {
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 6px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 11px;
  transition: all 0.2s;
}

.theme-toggle-btn:hover {
  background-color: var(--border-color);
}

/* 主显控板 */
.main-workspace {
  flex: 1;
  display: flex;
  flex-direction: column;
  height: 100%;
}

.top-nav {
  height: 64px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  background-color: var(--bg-sidebar);
}

.current-chapter-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-main);
}

.classroom-mode-tag {
  font-size: 11px;
  background-color: var(--success);
  color: #fff;
  padding: 4px 8px;
  border-radius: 4px;
  font-weight: 600;
}

/* 双栏排版：左边交互式仿真实验区，右边教案教辅区 */
.split-workspace {
  flex: 1;
  display: flex;
  overflow: hidden;
}

.simulation-panel {
  flex: 3;
  display: flex;
  flex-direction: column;
  padding: 20px;
  gap: 16px;
  overflow-y: auto;
  border-right: 1px solid var(--border-color);
  background-image: radial-gradient(circle at 50% 50%, rgba(2, 132, 199, 0.03) 0%, transparent 80%);
}

.canvas-card {
  background-color: var(--bg-panel);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 12px;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
  backdrop-filter: blur(10px);
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

canvas.physics-canvas {
  background-color: #151A26; /* 实验暗色背景 */
  border-radius: 8px;
  display: block;
  box-shadow: inset 0 0 20px rgba(0,0,0,0.8);
}

/* 控制按钮与参数调整 */
.controls-card {
  background-color: var(--bg-panel);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 16px;
  backdrop-filter: blur(10px);
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.control-group {
  flex: 1;
  min-width: 180px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.control-group label {
  font-size: 12px;
  font-weight: 600;
  color: var(--text-muted);
}

.control-group select,
.control-group input[type="range"] {
  width: 100%;
}

.range-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
}

.range-val {
  font-family: 'Outfit', sans-serif;
  font-size: 12px;
  font-weight: 700;
  color: var(--accent-color);
  min-width: 40px;
  text-align: right;
}

/* 滑杆高质感设计 */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  background: rgba(255, 255, 255, 0.1);
  height: 6px;
  border-radius: 3px;
  outline: none;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent-color);
  cursor: pointer;
  box-shadow: 0 0 8px var(--accent-glow);
  transition: transform 0.1s;
}

input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.25);
}

/* 按钮组 */
.btn-group {
  display: flex;
  gap: 8px;
}

.btn {
  padding: 8px 16px;
  font-size: 13px;
  font-weight: 600;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: all 0.2s;
  background-color: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
  display: flex;
  align-items: center;
  gap: 6px;
}

.btn:hover {
  background-color: var(--border-color);
}

.btn-primary {
  background-color: var(--accent-color);
  color: #fff;
  border-color: var(--accent-color);
}

.btn-primary:hover {
  background-color: #0369A1;
  box-shadow: 0 0 10px var(--accent-glow);
}

.btn-success {
  background-color: var(--success);
  color: #fff;
  border-color: var(--success);
}

/* 右侧教辅面板 */
.teaching-panel {
  flex: 2;
  min-width: 380px;
  background-color: var(--bg-sidebar);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.teaching-tabs {
  display: flex;
  border-bottom: 1px solid var(--border-color);
}

.tab-btn {
  flex: 1;
  background: none;
  border: none;
  padding: 16px 0;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
  position: relative;
  text-align: center;
}

.tab-btn:hover {
  color: var(--text-main);
}

.tab-btn.active {
  color: var(--accent-color);
}

.tab-btn.active::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 15%;
  width: 70%;
  height: 3px;
  background-color: var(--accent-color);
  border-radius: 2px 2px 0 0;
}

.tab-content-container {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
}

.tab-pane {
  display: none;
}

.tab-pane.active {
  display: block;
}

/* 教学要点样式 */
.lesson-section {
  margin-bottom: 20px;
  line-height: 1.6;
}

.lesson-section h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent-color);
  margin-bottom: 8px;
}

.lesson-section p {
  font-size: 13px;
  color: var(--text-muted);
  white-space: pre-wrap;
}

/* 实验步骤样式 */
.step-item {
  font-size: 13px;
  line-height: 1.6;
  margin-bottom: 12px;
  padding: 10px;
  background-color: rgba(255, 255, 255, 0.02);
  border-left: 3px solid var(--accent-color);
  border-radius: 0 4px 4px 0;
}

/* 问答 & 测验组件 */
.interactive-card {
  background-color: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 16px;
}

.question-text {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 12px;
}

.option-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.option-btn {
  width: 100%;
  padding: 10px 12px;
  text-align: left;
  background-color: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-main);
  cursor: pointer;
  font-size: 13px;
  transition: all 0.2s;
}

.option-btn:hover {
  background-color: rgba(2, 132, 199, 0.06);
  border-color: var(--accent-color);
}

.option-btn.selected {
  border-color: var(--accent-color);
  background-color: rgba(2, 132, 199, 0.1);
}

.option-btn.correct {
  background-color: rgba(16, 185, 129, 0.15);
  border-color: var(--success);
  color: var(--success);
}

.option-btn.wrong {
  background-color: rgba(239, 68, 68, 0.15);
  border-color: var(--danger);
  color: var(--danger);
}

.feedback-area {
  margin-top: 12px;
  padding: 10px;
  border-radius: 6px;
  font-size: 12.5px;
  display: none;
}

.feedback-area.correct {
  background-color: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.feedback-area.wrong {
  background-color: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.feedback-title {
  font-weight: 600;
  margin-bottom: 4px;
}

/* 砝码盒专用 UI */
.weights-box-container {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.weights-grid {
  display: flex;
  gap: 8px;
  margin-top: 6px;
}

.weight-selector-btn {
  background: radial-gradient(circle, #FBBF24 0%, #D97706 100%);
  border: 1.5px solid #78350F;
  color: #fff;
  border-radius: 50%;
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-size: 10px;
  cursor: pointer;
  box-shadow: 0 3px 6px rgba(0,0,0,0.3);
  transition: transform 0.1s;
}

.weight-selector-btn:active {
  transform: scale(0.9);
}

/* 平面镜天平辅助指示板 */
.live-readout-strip {
  display: flex;
  justify-content: space-between;
  background-color: rgba(2, 132, 199, 0.05);
  border: 1px solid var(--accent-glow);
  border-radius: 6px;
  padding: 10px 14px;
  margin-bottom: 12px;
  font-size: 12px;
}

.readout-item {
  display: flex;
  gap: 6px;
}

.readout-label {
  color: var(--text-muted);
}

.readout-val {
  font-family: 'Outfit', sans-serif;
  font-weight: 700;
  color: var(--accent-color);
}

/* 自定义对话框模态 */
.custom-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(0, 0, 0, 0.5);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  backdrop-filter: blur(4px);
}

.modal-content {
  background-color: var(--bg-sidebar);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  width: 400px;
  padding: 24px;
  box-shadow: 0 20px 40px rgba(0,0,0,0.5);
  text-align: center;
}

.modal-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--accent-color);
}

.modal-text {
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 20px;
}