/* ============================================
   杠精模拟器 - 游戏化样式 (v4.0)
   设计系统：暖色学术风 (哈老师 Design System v1.0)
   ============================================ */

/* ── 字体加载 ── */
@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;600;700;900&family=LXGW+WenKai:wght@300;400;700&display=swap');

:root {
  /* === 主强调色 === */
  --ac:    #c45d3e;   /* 陶土色（主色） */
  --acd:   #a34830;   /* 陶土色-深（hover/active） */
  --acl:   #f0d5cc;   /* 陶土色-浅（浅色背景/标签底色） */

  /* === 次强调色 === */
  --tl:    #2a7a6e;   /* 青绿色（次要强调色） */
  --tll:   #d4ede8;   /* 青绿色-浅 */

  /* === 第三强调色 === */
  --am:    #b8860b;   /* 琥珀金色（第三强调色） */
  --aml:   #fdf3dc;   /* 琥珀金色-浅 */

  /* === 背景色 === */
  --bg:    #faf8f5;   /* 主背景（暖白色） */
  --bgs:   #f5f0ea;   /* 次级背景（暖米色） */
  --bc:    #ffffff;   /* 卡片背景（纯白） */
  --bgh:   #f7f3ee;   /* 卡片悬停背景 */
  --bge:   #f0ebe4;   /* 提升背景（极浅暖色） */

  /* === 文本色 === */
  --tx:    #2c2420;   /* 主文本（深棕黑） */
  --txs:   #6b5e54;   /* 次要文本（中棕色） */
  --txt:   #9e8e80;   /* 第三级文本（浅棕灰） */

  /* === 边框色 === */
  --bd:    #e8e0d6;   /* 主边框（暖浅灰） */
  --bdl:   #f0ebe4;   /* 次级边框（极浅暖色） */

  /* === 语义色 === */
  --error: #d94040;   /* 错误/红色 */
  --ok:    #2a7a6e;   /* 成功/绿色 */
  --info:  #5b7fb5;   /* 信息/蓝色 */

  /* === 字体 === */
  --fd:    'Noto Serif SC', Georgia, 'Songti SC', serif;
  --fb:    'LXGW WenKai', -apple-system, BlinkMacSystemFont, 'PingFang SC', sans-serif;

  /* === 字号阶梯 === */
  --text-xs:    0.72rem;   /* 12px */
  --text-sm:    0.82rem;   /* 13px */
  --text-base:  0.88rem;   /* 14px */
  --text-md:    0.95rem;   /* 15px */
  --text-lg:    1rem;      /* 16px */
  --text-xl:    1.125rem;  /* 18px */
  --text-2xl:   1.25rem;   /* 20px */
  --text-3xl:   1.5rem;    /* 24px */
  --text-4xl:   2rem;      /* 32px */
  --text-hero:  clamp(2.4rem, 5.5vw, 3.6rem);

  /* === 字重 === */
  --fw-light:    300;
  --fw-regular:  400;
  --fw-medium:   500;
  --fw-semibold: 600;
  --fw-bold:     700;
  --fw-black:    900;

  /* === 间距阶梯 === */
  --space-1:  4px;
  --space-2:  8px;
  --space-3:  12px;
  --space-4:  16px;
  --space-5:  20px;
  --space-6:  24px;
  --space-7:  28px;
  --space-8:  32px;
  --space-9:  40px;
  --space-10: 48px;
  --space-11: 64px;
  --space-12: 80px;

  /* === 圆角阶梯 === */
  --radius-sm:   6px;
  --radius-md:   12px;
  --radius-lg:   16px;
  --radius-xl:   20px;
  --radius-pill: 100px;
  --radius-full: 50%;

  /* === 阴影阶梯 === */
  --shadow-xs:  0 1px 3px rgba(44,36,32,0.06);
  --shadow-sm:  0 2px 8px rgba(44,36,32,0.06);
  --shadow-md:  0 4px 16px rgba(44,36,32,0.08);
  --shadow-lg:  0 8px 32px rgba(44,36,32,0.1);
  --shadow-xl:  0 20px 60px rgba(44,36,32,0.12);
  --shadow-accent: 0 4px 16px rgba(196,93,62,0.25);

  /* === 渐变 === */
  --gradient-primary: linear-gradient(135deg, var(--ac), #d4724e);
  --gradient-progress: linear-gradient(90deg, var(--ac), var(--tl));
  --gradient-border: conic-gradient(from 0deg, var(--ac), var(--tl), var(--am), var(--ac));

  /* === 过渡 === */
  --transition-fast:   all 0.2s ease;
  --transition-normal: all 0.3s ease;
  --transition-slow:   all 0.4s ease;
  --transition-slide:  opacity 0.6s cubic-bezier(0.4,0,0.2,1),
                        transform 0.6s cubic-bezier(0.4,0,0.2,1);
}

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

html { font-size: 16px; scroll-behavior: smooth; }

body {
  font-family: var(--fb);
  background: var(--bg);
  color: var(--tx);
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  line-height: 1.8;
}

#app {
  min-height: 100vh;
  transition: opacity 0.3s ease;
}
#app.fade-in {
  animation: fadeIn 0.4s ease-out;
}

a { color: var(--ac); text-decoration: none; }
button { cursor: pointer; font-family: var(--fb); border: none; background: none; color: inherit; }
.hidden { display: none !important; }

/* ================================================
   按钮（对齐设计系统组件库）
   ================================================ */

/* 主按钮 CTA */
.btn-primary {
  display: inline-flex; align-items: center; gap: var(--space-2);
  padding: var(--space-3) var(--space-8);
  background: var(--gradient-primary);
  color: #fff;
  font-weight: var(--fw-bold);
  font-size: var(--text-xl);
  border-radius: var(--radius-lg);
  transition: var(--transition-fast);
  box-shadow: var(--shadow-accent);
  position: relative; overflow: hidden;
}
.btn-primary::after {
  content: ''; position: absolute; inset: 0;
  background: linear-gradient(135deg, transparent 40%, rgba(255,255,255,0.15) 50%, transparent 60%);
  transform: translateX(-100%); transition: transform 0.6s;
}
.btn-primary:hover::after { transform: translateX(100%); }
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(196,93,62,0.35);
}
.btn-primary:active { transform: translateY(0); }

.btn-primary.btn-glow {
  animation: btnGlow 2s ease-in-out infinite;
}

/* 次级按钮 */
.btn-secondary {
  display: inline-flex; align-items: center; gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  background: var(--bc);
  border: 1px solid var(--bdl);
  color: var(--tx);
  font-weight: var(--fw-semibold);
  font-size: var(--text-lg);
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
}
.btn-secondary:hover {
  background: var(--bgh);
  border-color: var(--ac);
}

/* 返回按钮 */
.btn-back {
  display: flex; align-items: center; justify-content: center;
  width: 40px; height: 40px;
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  color: var(--txs);
  font-size: var(--text-md);
  transition: var(--transition-fast);
}
.btn-back:hover { border-color: var(--ac); color: var(--ac); }

/* ── 屏幕通用 ── */
.screen {
  max-width: 860px;
  margin: 0 auto;
  padding: var(--space-6) var(--space-5);
}
.screen-header {
  margin-bottom: var(--space-7);
  display: flex; align-items: center; gap: var(--space-4);
}
.screen-header h2 {
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-bold);
  display: flex; align-items: center; gap: var(--space-3);
}
.screen-header p {
  color: var(--txs);
  font-size: var(--text-md);
  margin-top: var(--space-1);
}

/* ================================================
   头像系统
   ================================================ */
.avatar-img {
  object-fit: cover;
  border-radius: inherit;
  display: block;
  transition: filter 0.4s ease, transform 0.3s ease;
}

.avatar-emoji-fallback {
  display: none;
  align-items: center;
  justify-content: center;
  border-radius: inherit;
}

.avatar-mood-angry {
  filter: saturate(1.3) contrast(1.1);
  transform: rotate(-3deg);
}
.avatar-mood-happy {
  filter: brightness(1.1) saturate(1.1);
}
.avatar-mood-thinking {
  filter: grayscale(0.3) brightness(0.95);
}
.avatar-mood-satisfied {
  filter: brightness(1.05) sepia(0.1);
}

/* ================================================
   欢迎页（Hero 区域）
   ================================================ */
.welcome-screen {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding: var(--space-10) var(--space-5);
  background:
    radial-gradient(ellipse at 50% 60%, rgba(196,93,62,0.06) 0%, transparent 60%),
    repeating-linear-gradient(0deg, transparent, transparent 59px, rgba(196,93,62,0.025) 59px, rgba(196,93,62,0.025) 60px),
    repeating-linear-gradient(90deg, transparent, transparent 59px, rgba(196,93,62,0.025) 59px, rgba(196,93,62,0.025) 60px),
    var(--bg);
}

.welcome-particles {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.particle {
  position: absolute;
  bottom: -10px;
  background: var(--ac);
  border-radius: var(--radius-full);
  animation: particleRise linear infinite;
  width: 3px;
  height: 3px;
}

.particle-book {
  background: none;
  width: 8px !important;
  height: 6px !important;
  border: 1.5px solid rgba(196,93,62,0.4);
  border-radius: 1px;
}
.particle-book::before {
  content: '';
  position: absolute;
  left: 50%;
  top: -1px;
  bottom: -1px;
  width: 1px;
  background: rgba(196,93,62,0.3);
}

.particle-bubble {
  background: none !important;
  width: 10px !important;
  height: 8px !important;
  border: 1.5px solid rgba(196,93,62,0.35);
  border-radius: var(--radius-full);
}
.particle-bubble::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 3px;
  width: 0;
  height: 0;
  border-left: 2px solid transparent;
  border-right: 2px solid transparent;
  border-top: 3px solid rgba(196,93,62,0.35);
}

.welcome-content {
  text-align: center;
  position: relative;
  z-index: 1;
}

.welcome-badge {
  display: inline-block;
  padding: var(--space-1) var(--space-4);
  background: rgba(196,93,62,0.09);
  border: 1px solid rgba(196,93,62,0.5);
  border-radius: var(--radius-pill);
  color: var(--ac);
  font-size: var(--text-md);
  font-weight: var(--fw-semibold);
  margin-bottom: var(--space-5);
  letter-spacing: 2px;
  animation: fadeIn 0.6s ease-out 0.2s backwards;
}

.welcome-title {
  font-family: var(--fd);
  font-size: var(--text-hero);
  font-weight: var(--fw-black);
  margin-bottom: var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
}

.title-char {
  display: inline-block;
  background: linear-gradient(180deg, var(--tx) 30%, var(--ac));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: titleCharIn 0.6s ease-out backwards;
  position: relative;
  text-shadow: none;
}
.title-char::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(196,93,62,0.2), transparent);
  -webkit-background-clip: text;
  background-clip: text;
  animation: charShine 3s ease-in-out infinite;
}
.title-char:nth-child(1) { animation-delay: 0.1s; }
.title-char:nth-child(2) { animation-delay: 0.2s; }
.title-char:nth-child(3) { animation-delay: 0s; }
.title-char:nth-child(4) { animation-delay: 0.3s; }
.title-char:nth-child(5) { animation-delay: 0.4s; }
.title-char:nth-child(6) { animation-delay: 0.5s; }

.title-spacer { width: var(--space-4); }

.welcome-subtitle {
  color: var(--txs);
  font-size: var(--text-xl);
  margin-bottom: var(--space-9);
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
  animation: fadeIn 0.6s ease-out 0.6s backwards;
}

.welcome-features {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-10);
}

.feature-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  color: var(--txs);
  font-size: var(--text-md);
  padding: var(--space-3) var(--space-5);
  background: var(--bc);
  border-radius: var(--radius-md);
  border: 1px solid var(--bd);
  border-left: 3px solid rgba(196,93,62,0.4);
  animation: featureSlideIn 0.5s ease-out backwards;
}
.feature-item:nth-child(1) { animation-delay: 0.7s; }
.feature-item:nth-child(2) { animation-delay: 0.85s; }
.feature-item:nth-child(3) { animation-delay: 1.0s; }
.feature-item i {
  color: var(--ac);
  font-size: var(--text-lg);
  width: var(--space-5);
  text-align: center;
}

.welcome-footer {
  position: absolute;
  bottom: var(--space-5);
  color: var(--txt);
  font-size: var(--text-sm);
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.copyright-line {
  font-size: var(--text-xs);
  opacity: 0.7;
}

/* ================================================
   欢迎页双按钮
   ================================================ */
.welcome-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-4);
}
.welcome-actions .btn-primary {
  min-width: 260px;
  justify-content: center;
}

/* 与 btn-primary 同尺寸，仅色彩不同（青绿色系） */
.btn-secondary-accent {
  background: linear-gradient(135deg, var(--tl), #3a9a8e);
  box-shadow: 0 4px 16px rgba(42,122,110,0.25);
  color: #fff;
}
.btn-secondary-accent::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 40%, rgba(255,255,255,0.15) 50%, transparent 60%);
  transform: translateX(-100%);
  transition: transform 0.6s;
}
.btn-secondary-accent:hover::after {
  transform: translateX(100%);
}
.btn-secondary-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(42,122,110,0.35);
}

/* ================================================
   AI 自定义课题表单
   ================================================ */
.custom-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-label {
  font-weight: var(--fw-semibold);
  font-size: var(--text-lg);
  color: var(--tx);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}
.form-label i {
  color: var(--ac);
  width: var(--space-5);
  text-align: center;
}

.form-select,
.form-input,
.form-textarea {
  padding: var(--space-4);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  font-family: var(--fb);
  font-size: var(--text-lg);
  color: var(--tx);
  transition: var(--transition-fast);
  -webkit-appearance: none;
  appearance: none;
}

.form-textarea {
  resize: vertical;
  line-height: 1.7;
  min-height: 120px;
}
.form-textarea:focus {
  outline: none;
  border-color: var(--ac);
  box-shadow: 0 0 0 3px rgba(196,93,62,0.1);
}
.form-select {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' stroke='%239e8e80' stroke-width='2' fill='none'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--space-4) center;
  padding-right: var(--space-10);
}
.form-select:focus,
.form-input:focus {
  outline: none;
  border-color: var(--ac);
  box-shadow: 0 0 0 3px rgba(196,93,62,0.1);
}

.form-hint {
  font-size: var(--text-sm);
  color: var(--txt);
  line-height: 1.5;
}

.form-error {
  padding: var(--space-3) var(--space-4);
  background: rgba(217,64,64,0.08);
  border: 1px solid rgba(217,64,64,0.25);
  border-radius: var(--radius-md);
  color: var(--error);
  font-size: var(--text-base);
  animation: fadeIn 0.3s ease-out;
}

.custom-notice {
  display: flex;
  align-items: flex-start;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  background: var(--aml);
  border: 1px solid var(--am);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  color: var(--txs);
  line-height: 1.6;
}

.custom-notice i {
  color: var(--am);
  margin-top: 2px;
  flex-shrink: 0;
}

.custom-notice strong {
  color: var(--am);
}

.custom-submit {
  align-self: center;
  margin-top: var(--space-3);
}

/* ================================================
   AI 生成中加载页
   ================================================ */
.generating-screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-10) var(--space-5);
  background:
    radial-gradient(ellipse at 50% 40%, rgba(196,93,62,0.06) 0%, transparent 60%),
    var(--bg);
}

.generating-content {
  text-align: center;
  max-width: 500px;
}

.generating-students {
  display: flex;
  justify-content: center;
  gap: var(--space-5);
  margin-bottom: var(--space-10);
}

.gen-student {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  animation: float 3s ease-in-out infinite;
  animation-delay: var(--delay);
}

.gen-student-avatar {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  border: 2px solid var(--student-color);
  overflow: hidden;
  opacity: 0.7;
  animation: genPulse 2s ease-in-out infinite;
  animation-delay: var(--delay);
}

.gen-thinking-dots {
  display: flex;
  gap: 3px;
}

.dot {
  width: 4px;
  height: 4px;
  border-radius: var(--radius-full);
  background: var(--txt);
  animation: dotBounce 1.4s ease-in-out infinite;
  animation-delay: var(--dot-delay);
}

.gen-status {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
  margin-bottom: var(--space-8);
}

.gen-spinner {
  width: 28px;
  height: 28px;
  border: 3px solid var(--bd);
  border-top-color: var(--ac);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
  flex-shrink: 0;
}

.gen-title {
  font-family: var(--fd);
  font-size: var(--text-xl);
  font-weight: var(--fw-bold);
  color: var(--tx);
}

.gen-subtitle {
  font-size: var(--text-base);
  color: var(--txt);
  margin-top: var(--space-1);
}

.gen-tips {
  position: relative;
  height: 40px;
}

.gen-tip {
  position: absolute;
  width: 100%;
  font-size: var(--text-base);
  color: var(--txs);
  opacity: 0;
  transform: translateY(8px);
  transition: all 0.5s ease;
}
.gen-tip.active {
  opacity: 1;
  transform: translateY(0);
}

/* ── AI 生成进度条 ── */
.gen-progress-section {
  width: 100%;
  max-width: 420px;
  margin: 0 auto;
}

.gen-progress-title {
  font-family: var(--fd);
  font-size: var(--text-xl);
  font-weight: var(--fw-bold);
  color: var(--tx);
  margin-bottom: var(--space-5);
}

.gen-progress-bar {
  width: 100%;
  height: 8px;
  background: var(--bge);
  border-radius: var(--radius-pill);
  overflow: hidden;
}

.gen-progress-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--ac), var(--am));
  border-radius: var(--radius-pill);
  transition: width 5s cubic-bezier(0.4, 0, 0.2, 1);
}

.gen-progress-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--space-3);
}

.gen-progress-text {
  font-size: var(--text-sm);
  color: var(--txs);
  font-family: var(--fb);
  transition: opacity 0.2s ease;
}

.gen-progress-pct {
  font-size: var(--text-sm);
  color: var(--am);
  font-weight: var(--fw-bold);
  font-family: var(--fd);
  min-width: 36px;
  text-align: right;
  transition: color 0.3s ease;
}

/* 学生头像激活状态 */
.gen-student.gen-student-active .gen-student-avatar {
  opacity: 1;
  border-color: var(--am);
  box-shadow: 0 0 0 3px rgba(184, 134, 11, 0.2);
  transform: scale(1.1);
}

.gen-student.gen-student-active {
  opacity: 1;
}

/* 完成状态 */
.gen-progress-fill.complete {
  background: linear-gradient(90deg, var(--ok), #34d399);
}

/* ================================================
   场景选择（card-callout 变体）
   ================================================ */
.scenario-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.scenario-card {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-5);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-lg);
  transition: var(--transition-fast);
}
.scenario-card:hover {
  background: var(--bgh);
  border-color: rgba(196,93,62,0.5);
  transform: translateX(4px);
}

.scenario-icon {
  font-size: 2.4rem;
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bge);
  border-radius: var(--radius-md);
}

.scenario-info {
  flex: 1;
  min-width: 0;
}
.scenario-info h3 {
  font-family: var(--fd);
  font-size: var(--text-2xl);
  font-weight: var(--fw-bold);
  margin-bottom: var(--space-2);
}
.scenario-meta {
  display: flex; gap: var(--space-2);
  margin-bottom: var(--space-2);
}

/* 药丸标签 */
.tag {
  display: inline-block;
  padding: 2px 10px;
  background: var(--bge);
  border-radius: var(--radius-pill);
  font-size: var(--text-sm);
  color: var(--txs);
}
.scenario-desc {
  color: var(--txs);
  font-size: var(--text-base);
  margin-bottom: var(--space-2);
  line-height: 1.5;
}
.scenario-difficulty {
  color: var(--ac);
  font-size: var(--text-md);
}
.scenario-rounds {
  color: var(--txt);
  font-size: var(--text-sm);
}
.scenario-arrow {
  color: var(--txt);
  font-size: var(--text-md);
  flex-shrink: 0;
}

/* ================================================
   阵容展示
   ================================================ */
.roster-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

.roster-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: var(--space-4) var(--space-5);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-left: 3px solid var(--student-color);
  border-radius: var(--radius-md);
  animation: rosterSlideIn 0.4s ease-out backwards;
}
.roster-avatar {
  width: 48px; height: 48px;
  border-radius: var(--radius-md);
  border: 2px solid;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  overflow: hidden;
}
.avatar-emoji { font-size: 1.5rem; }

.roster-info { flex: 1; min-width: 0; }
.roster-name { font-weight: var(--fw-bold); font-size: var(--text-xl); }
.roster-type { font-size: var(--text-md); font-weight: var(--fw-semibold); }
.roster-tagline { color: var(--txt); font-size: var(--text-sm); margin-top: 2px; }

.roster-skill { text-align: right; flex-shrink: 0; }
.skill-label { font-size: var(--text-xs); color: var(--txt); }
.skill-name { font-size: var(--text-md); color: var(--ac); font-weight: var(--fw-semibold); }

.roster-rounds {
  color: var(--txt);
  font-size: var(--text-sm);
  flex-shrink: 0;
  padding: var(--space-1) var(--space-3);
  background: var(--bge);
  border-radius: var(--radius-pill);
}

.roster-action {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex-wrap: wrap;
}
.teacher-content-preview {
  color: var(--txs);
  font-size: var(--text-md);
  cursor: pointer;
  transition: color 0.2s;
  display: flex; align-items: center; gap: var(--space-2);
}
.teacher-content-preview:hover { color: var(--ac); }

/* ── 老师原文面板 ── */
.teacher-content-panel {
  margin: var(--space-4) 0;
  max-height: 300px;
  overflow-y: auto;
}
.content-panel-inner {
  padding: var(--space-5);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  line-height: 1.8;
  color: var(--txs);
  font-size: var(--text-base);
}

/* ================================================
   战斗界面
   ================================================ */
.battle-screen {
  max-width: 760px;
  padding-top: var(--space-4);
}

.battle-screen.wave-tense {
  animation: waveTensePulse 1.5s ease-in-out;
}

/* ── HUD ── */
.hud {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-4);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-3);
}
.hud-left { flex: 1; min-width: 0; }
.hud-center { flex-shrink: 0; }
.hud-right {
  flex-shrink: 0;
  text-align: right;
  display: flex; flex-direction: column; gap: var(--space-1);
  align-items: flex-end;
}

/* ── 课堂氛围数轴 ── */
.atmosphere-bar-container {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.atmosphere-label {
  font-size: var(--text-xs);
  color: var(--txt);
  white-space: nowrap;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.atmosphere-scale {
  position: relative;
  height: var(--space-6);
  background: linear-gradient(90deg,
    var(--error) 0%,
    var(--am) 35%,
    var(--ac) 50%,
    var(--tl) 70%,
    var(--tl) 100%
  );
  border-radius: var(--radius-pill);
  overflow: hidden;
  border: 1px solid var(--bd);
}

.atmosphere-marker {
  position: absolute;
  top: 2px;
  bottom: 2px;
  width: var(--space-5);
  background: var(--ac);
  border: 2px solid #fff;
  border-radius: var(--radius-full);
  transform: translateX(-50%);
  transition: left 0.5s ease, background 0.3s ease;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
  z-index: 1;
}

.atmosphere-marker.atmosphere-shift-up {
  animation: atmosphereRise 0.5s ease-out;
}

.atmosphere-marker.atmosphere-shift-down {
  animation: atmosphereFall 0.5s ease-out;
}

.atmosphere-labels {
  position: absolute;
  inset: 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 var(--space-2);
  pointer-events: none;
}

.atm-label-left,
.atm-label-center,
.atm-label-right {
  font-size: 0.6rem;
  color: rgba(255,255,255,0.9);
  font-weight: var(--fw-semibold);
  text-shadow: 0 1px 2px rgba(0,0,0,0.3);
}

.atm-label-left { margin-left: -4px; }
.atm-label-center { position: absolute; left: 50%; transform: translateX(-50%); }
.atm-label-right { margin-right: -4px; }

.atmosphere-value {
  font-size: var(--text-sm);
  color: var(--txs);
  font-weight: var(--fw-semibold);
  white-space: nowrap;
  text-align: center;
}

/* ── 氛围变化反馈 ── */
.atmosphere-change {
  font-size: var(--text-sm);
  color: var(--txt);
  font-weight: var(--fw-semibold);
  padding: var(--space-1) var(--space-3);
  background: var(--bge);
  border-radius: var(--radius-pill);
}

.wave-indicator {
  text-align: center;
}
.wave-indicator .wave-label {
  font-size: var(--text-sm);
  font-weight: var(--fw-bold);
  color: var(--ac);
  text-transform: uppercase;
  letter-spacing: 1px;
  padding: 3px 10px;
  background: rgba(196,93,62,0.09);
  border-radius: var(--radius-pill);
  display: inline-block;
}

.round-counter {
  font-family: var(--fd);
  font-size: var(--text-md);
  font-weight: var(--fw-bold);
  color: var(--txt);
  letter-spacing: 2px;
  text-align: center;
  margin-top: 2px;
}

.score-display {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
}
.score-label {
  font-size: var(--text-xs);
  color: var(--txt);
  letter-spacing: 2px;
}
.score-value {
  font-family: var(--fd);
  font-size: var(--text-3xl);
  font-weight: var(--fw-black);
  color: var(--ac);
}
.score-pop {
  animation: scorePop 0.3s ease-out;
}

.combo-display {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
}
.combo-count {
  font-family: var(--fd);
  font-size: var(--text-xl);
  font-weight: var(--fw-black);
  color: var(--error);
}
.combo-count.combo-fire {
  animation: comboFire 0.6s ease-in-out infinite;
}
.combo-label {
  font-size: var(--text-xs);
  color: var(--txt);
  letter-spacing: 2px;
}

/* ── 老师原文折叠 ── */
.battle-content {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  color: var(--txt);
  font-size: var(--text-sm);
  cursor: pointer;
  transition: color 0.2s;
  margin-bottom: var(--space-1);
}
.battle-content:hover { color: var(--ac); }

/* ── 战斗区域 ── */
.battle-arena {
  min-height: 400px;
  position: relative;
}

.battle-arena.fail-shake {
  animation: failShake 0.35s ease-out;
}

/* ── 屏幕闪光效果 ── */
.screen-flash {
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  animation: screenFlash 0.25s ease-out forwards;
}

/* ── 星星爆裂效果 ── */
.star-burst {
  position: absolute;
  color: var(--ac);
  font-size: var(--text-xl);
  pointer-events: none;
  z-index: 10;
  animation: starBurst 0.5s ease-out forwards;
}

/* ── Round Intro (VS screen) ── */
.round-intro {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-8);
  padding: var(--space-10) var(--space-5);
  position: relative;
}

.vs-flash {
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, rgba(196,93,62,0.1) 0%, transparent 70%);
  animation: vsFlash 1.5s ease-out;
}

.intro-student, .intro-teacher {
  text-align: center;
  z-index: 1;
}
.intro-avatar-ring {
  width: 80px; height: 80px;
  margin: 0 auto var(--space-3);
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
}
.intro-avatar-ring::before {
  content: '';
  position: absolute;
  inset: -4px;
  border-radius: var(--radius-full);
  border: 2px solid var(--student-color, var(--ac));
  animation: ringPulse 1.5s ease-in-out infinite;
}
.intro-avatar {
  width: 80px; height: 80px;
  border-radius: var(--radius-full);
  border: 3px solid;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.2rem;
  background: var(--bc);
  overflow: hidden;
}
.teacher-avatar { border-color: var(--ac) !important; }

.intro-name {
  font-family: var(--fd);
  font-size: var(--text-xl);
  font-weight: var(--fw-bold);
  margin-bottom: var(--space-1);
}
.intro-type { font-size: var(--text-md); font-weight: var(--fw-semibold); margin-bottom: var(--space-1); }
.intro-skill {
  font-size: var(--text-sm);
  color: var(--ac);
  padding: 2px var(--space-3);
  background: rgba(196,93,62,0.09);
  border-radius: var(--radius-pill);
  display: inline-block;
}

.intro-vs {
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-black);
  color: var(--ac);
  text-shadow: 0 0 30px rgba(196,93,62,0.4);
  z-index: 1;
  animation: vsScale 0.6s ease-out;
}

/* ── 问题区域 ── */
.question-area {
  padding: 0;
}

.question-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.question-student {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}
.q-avatar {
  width: 40px; height: 40px;
  border-radius: var(--radius-md);
  border: 2px solid;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  background: var(--bc);
  overflow: hidden;
}
.q-name { font-weight: var(--fw-bold); font-size: var(--text-lg); }
.q-type {
  font-size: var(--text-sm);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  font-weight: var(--fw-semibold);
}

.q-wave-badge {
  font-size: var(--text-xs);
  padding: 2px var(--space-2);
  background: rgba(196,93,62,0.09);
  color: var(--ac);
  border-radius: var(--radius-pill);
  font-weight: var(--fw-bold);
  letter-spacing: 1px;
}

.question-meta {
  display: flex;
  gap: var(--space-2);
}
.difficulty-badge, .category-badge {
  font-size: var(--text-sm);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-pill);
  border: 1px solid;
  display: flex;
  align-items: center;
  gap: var(--space-1);
}
.difficulty-badge { border-color: currentColor; }
.category-badge {
  color: var(--txs);
  border-color: var(--bd);
}

/* ── 问题气泡 ── */
.question-bubble {
  position: relative;
  padding: var(--space-5) var(--space-6);
  background: var(--bc);
  border: 1px solid;
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-6);
  margin-left: var(--space-5);
}
.bubble-tail {
  position: absolute;
  left: -8px;
  top: var(--space-5);
  width: 0; height: 0;
  border: 8px solid transparent;
  border-right-color: inherit;
  border-left: 0;
}
.question-text {
  font-size: var(--text-xl);
  line-height: 1.7;
  color: var(--tx);
}

/* ── 选项 ── */
.options-label {
  font-size: var(--text-md);
  color: var(--txt);
  margin-bottom: var(--space-3);
  padding-left: var(--space-1);
}

.options-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.option-card {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: 14px 18px;
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
  cursor: pointer;
}
.option-card:hover {
  background: var(--bgh);
  border-color: rgba(196,93,62,0.6);
  transform: translateX(4px);
}
.option-card:active {
  transform: scale(0.98) translateX(4px);
}

.option-label {
  flex-shrink: 0;
  width: 28px; height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bge);
  border-radius: var(--radius-sm);
  font-family: var(--fd);
  font-weight: var(--fw-bold);
  font-size: var(--text-md);
  color: var(--txt);
}
.option-card:hover .option-label {
  background: rgba(196,93,62,0.09);
  color: var(--ac);
}

.option-text {
  font-size: var(--text-md);
  line-height: 1.6;
  color: var(--tx);
  padding-top: 3px;
}

/* 选项状态 */
.option-card.option-selected {
  border-color: var(--ac);
  background: rgba(196,93,62,0.09);
}
.option-card.option-dimmed {
  opacity: 0.35;
  cursor: default;
}

/* ── 反馈面板 ── */
.feedback-panel {
  margin-top: var(--space-5);
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  border: 1px solid var(--bd);
  position: relative;
  animation: feedbackSlideUp 0.4s ease-out;
}
.feedback-panel.feedback-perfect {
  background: linear-gradient(135deg, rgba(42,122,110,0.08), rgba(42,122,110,0.02));
  border-color: rgba(42,122,110,0.25);
}
.feedback-panel.feedback-good {
  background: linear-gradient(135deg, rgba(91,127,181,0.08), rgba(91,127,181,0.02));
  border-color: rgba(91,127,181,0.25);
}
.feedback-panel.feedback-miss {
  background: linear-gradient(135deg, rgba(184,134,11,0.08), rgba(184,134,11,0.02));
  border-color: rgba(184,134,11,0.25);
}
.feedback-panel.feedback-fail {
  background: linear-gradient(135deg, rgba(217,64,64,0.08), rgba(217,64,64,0.02));
  border-color: rgba(217,64,64,0.25);
}

.feedback-score-popup {
  position: absolute;
  top: -14px;
  right: var(--space-5);
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-black);
  animation: scoreFloatScale 0.8s ease-out;
}
.feedback-score-perfect { color: var(--ok); text-shadow: 0 0 12px rgba(42,122,110,0.4); }
.feedback-score-good { color: var(--info); }
.feedback-score-miss { color: var(--am); }
.feedback-score-fail { color: var(--error); text-shadow: 0 0 12px rgba(217,64,64,0.4); }

.feedback-perfect .feedback-score-popup { color: var(--ok); }
.feedback-good .feedback-score-popup { color: var(--info); }
.feedback-miss .feedback-score-popup { color: var(--am); }
.feedback-fail .feedback-score-popup { color: var(--error); }

.feedback-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: 14px;
}

.feedback-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-1) 14px;
  border-radius: var(--radius-pill);
  font-size: var(--text-md);
  font-weight: var(--fw-bold);
}
.feedback-badge.feedback-perfect { background: rgba(42,122,110,0.12); color: var(--ok); }
.feedback-badge.feedback-good { background: rgba(91,127,181,0.12); color: var(--info); }
.feedback-badge.feedback-miss { background: rgba(184,134,11,0.12); color: var(--am); }
.feedback-badge.feedback-fail { background: rgba(217,64,64,0.12); color: var(--error); }

.combo-bonus {
  font-size: var(--text-sm);
  color: var(--ac);
  font-weight: var(--fw-bold);
  animation: comboPop 0.4s ease-out;
}
.combo-streak {
  font-size: var(--text-md);
  font-weight: var(--fw-bold);
}

.feedback-body {
  line-height: 1.8;
  color: var(--txs);
  font-size: var(--text-base);
}

.feedback-action {
  margin-top: var(--space-5);
  display: flex;
  justify-content: flex-end;
}

.btn-next {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  background: var(--bge);
  border: 1px solid var(--bdl);
  border-radius: var(--radius-md);
  color: var(--tx);
  font-weight: var(--fw-semibold);
  font-size: var(--text-md);
  transition: var(--transition-fast);
}
.btn-next:hover {
  background: rgba(196,93,62,0.09);
  border-color: var(--ac);
  color: var(--ac);
}

/* ── Wave 过渡动画 ── */
.wave-transition {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px var(--space-5);
  min-height: 300px;
}
.wave-transition-inner {
  text-align: center;
  animation: waveAnnounce 0.6s ease-out;
}
.wave-icon {
  font-size: 3rem;
  margin-bottom: var(--space-3);
  animation: waveSpin 1s ease-out;
}
.wave-label-big {
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-black);
  color: var(--ac);
  margin-bottom: var(--space-2);
}
.wave-subtitle {
  color: var(--txt);
  font-size: var(--text-md);
}

/* ── 学生应对表现 ── */
.perf-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}
.perf-card {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 14px var(--space-4);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
}
.perf-student {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  min-width: 140px;
  flex-shrink: 0;
}
.perf-avatar-wrap {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  flex-shrink: 0;
}
.perf-avatar { font-size: 1.4rem; }
.perf-info { min-width: 0; }
.perf-name { font-weight: var(--fw-bold); font-size: var(--text-base); }
.perf-type { font-size: var(--text-sm); }
.perf-bar-container {
  flex: 1;
  height: var(--space-2);
  background: var(--bg);
  border-radius: var(--radius-pill);
  overflow: hidden;
  min-width: 60px;
}
.perf-bar {
  height: 100%;
  border-radius: var(--radius-pill);
  transition: width 0.6s ease;
}
.perf-stat {
  font-size: var(--text-sm);
  color: var(--txt);
  white-space: nowrap;
  flex-shrink: 0;
  min-width: 90px;
  text-align: right;
}

/* ── 教学建议（card-callout 变体） ── */
.suggestions-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.suggestion-card {
  display: flex;
  gap: 14px;
  padding: var(--space-4);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  border-left: 3px solid;
}
.suggestion-card.suggestion-strength {
  border-left-color: var(--ok);
  background: linear-gradient(90deg, rgba(42,122,110,0.06), var(--bc));
}
.suggestion-card.suggestion-warning {
  border-left-color: var(--error);
  background: linear-gradient(90deg, rgba(217,64,64,0.06), var(--bc));
}
.suggestion-card.suggestion-improvement {
  border-left-color: var(--am);
  background: linear-gradient(90deg, rgba(184,134,11,0.06), var(--bc));
}
.suggestion-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  overflow: hidden;
  flex-shrink: 0;
}
.suggestion-type {
  font-size: var(--text-sm);
  font-weight: var(--fw-bold);
  color: var(--txt);
  margin-bottom: var(--space-1);
}
.suggestion-text p {
  font-size: var(--text-md);
  line-height: 1.6;
  color: var(--txs);
}

/* ================================================
   结果页
   ================================================ */
.result-screen { padding-bottom: 60px; position: relative; overflow: hidden; }

.result-hero {
  text-align: center;
  padding: var(--space-10) var(--space-5);
  margin-bottom: var(--space-7);
  background: linear-gradient(180deg, var(--rank-color)10, transparent);
  border-radius: var(--radius-xl);
  border: 1px solid var(--rank-color)25;
}

.result-rank-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-3) auto;
  width: 140px;
  height: 140px;
  flex-shrink: 0;
}

.rank-badge-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.rank-icon { font-size: 2.4rem; }
.rank-letter {
  font-family: var(--fd);
  font-size: 3.5rem;
  font-weight: var(--fw-black);
  color: var(--rank-color);
  text-shadow: 0 0 30px var(--rank-color)50;
}

.rank-title {
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-bold);
  margin-bottom: var(--space-2);
}
.rank-desc {
  color: var(--txs);
  font-size: var(--text-md);
  max-width: 400px;
  margin: 0 auto;
}

/* ── 数据卡片 ── */
.result-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-3);
  margin-bottom: var(--space-8);
}
.stat-card {
  padding: var(--space-4);
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  text-align: center;
}
.stat-value {
  font-family: var(--fd);
  font-size: var(--text-4xl);
  font-weight: var(--fw-black);
  color: var(--ac);
}
.stat-label {
  font-size: var(--text-sm);
  color: var(--txt);
  margin-top: var(--space-1);
}
.stat-perfect .stat-value { color: var(--ok); }
.stat-fail .stat-value { color: var(--error); }

/* ── 盲点报告 ── */
.result-section {
  margin-bottom: var(--space-7);
}
.result-section h3 {
  font-family: var(--fd);
  font-size: var(--text-2xl);
  font-weight: var(--fw-bold);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.result-perfect-banner {
  text-align: center;
  padding: var(--space-8);
  background: var(--bc);
  border: 1px solid rgba(42,122,110,0.2);
  border-radius: var(--radius-lg);
}
.result-perfect-banner .fa-trophy { font-size: 2rem; color: var(--ac); margin-bottom: var(--space-3); display: block; }
.result-perfect-banner h3 { justify-content: center; color: var(--ok); }
.result-perfect-banner p { color: var(--txs); }

.blindspot-category {
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-3);
  overflow: hidden;
}
.blindspot-cat-header {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  background: var(--bge);
  font-weight: var(--fw-semibold);
  font-size: var(--text-base);
}
.blindspot-cat-header i { color: var(--ac); }
.blindspot-cat-desc {
  color: var(--txt);
  font-size: var(--text-sm);
  font-weight: var(--fw-regular);
  margin-left: auto;
}
.blindspot-items { padding: var(--space-3) var(--space-4); }

.blindspot-item {
  padding: var(--space-3) 0;
  border-bottom: 1px solid var(--bd);
}
.blindspot-item:last-child { border-bottom: none; }
.blindspot-question {
  font-size: var(--text-md);
  margin-bottom: var(--space-2);
  line-height: 1.6;
}
.blindspot-student { font-weight: var(--fw-semibold); }
.blindspot-better {
  font-size: var(--text-base);
  color: var(--ok);
  line-height: 1.6;
}
.better-label { font-weight: var(--fw-bold); }

/* ── 详细回顾 ── */
.result-rounds {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.result-round {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) 14px;
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-md);
  font-size: var(--text-base);
}
.rr-number {
  width: 26px; height: 26px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bge);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--txt);
  flex-shrink: 0;
}
.rr-student { font-weight: var(--fw-semibold); flex-shrink: 0; }
.rr-question {
  flex: 1;
  color: var(--txs);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.rr-quality {
  font-size: var(--text-sm);
  font-weight: var(--fw-bold);
  padding: 2px 10px;
  border-radius: var(--radius-pill);
  flex-shrink: 0;
}
.rr-quality.quality-perfect { background: rgba(42,122,110,0.12); color: var(--ok); }
.rr-quality.quality-good { background: rgba(91,127,181,0.12); color: var(--info); }
.rr-quality.quality-miss { background: rgba(184,134,11,0.12); color: var(--am); }
.rr-quality.quality-fail { background: rgba(217,64,64,0.12); color: var(--error); }
.rr-score {
  font-family: var(--fd);
  font-weight: var(--fw-bold);
  flex-shrink: 0;
  min-width: 36px;
  text-align: right;
}

.result-actions {
  display: flex;
  gap: var(--space-3);
  justify-content: center;
  margin-top: var(--space-9);
}

/* ── 彩纸效果 ── */
.confetti-container {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 100;
  overflow: hidden;
}
.confetti-piece {
  position: absolute;
  top: -10px;
  border-radius: 2px;
  animation: confettiFall linear forwards;
}

/* ================================================
   动画（对齐设计系统动画规范）
   ================================================ */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes titleCharIn {
  from { opacity: 0; transform: translateY(20px) scale(0.8); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

@keyframes charShine {
  0%, 100% { opacity: 0; transform: translateX(-100%); }
  50% { opacity: 1; transform: translateX(100%); }
}

@keyframes featureSlideIn {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes particleRise {
  0% { transform: translateY(0) scale(1); opacity: 0; }
  10% { opacity: var(--o, 0.3); }
  90% { opacity: 0; }
  100% { transform: translateY(-100vh) scale(0.5); opacity: 0; }
}

@keyframes btnGlow {
  0%, 100% { box-shadow: var(--shadow-accent); }
  50% { box-shadow: 0 4px 30px rgba(196,93,62,0.45); }
}

@keyframes vsFlash {
  0% { opacity: 0.8; }
  100% { opacity: 0; }
}

@keyframes vsScale {
  0% { transform: scale(3); opacity: 0; }
  60% { transform: scale(0.9); opacity: 1; }
  100% { transform: scale(1); opacity: 1; }
}

@keyframes ringPulse {
  0%, 100% { transform: scale(1); opacity: 0.5; }
  50% { transform: scale(1.1); opacity: 1; }
}

@keyframes atmosphereRise {
  0% { transform: translateX(-50%) translateY(0); }
  30% { transform: translateX(-50%) translateY(-4px); }
  100% { transform: translateX(-50%) translateY(0); }
}

@keyframes atmosphereFall {
  0% { transform: translateX(-50%) translateY(0); }
  30% { transform: translateX(-50%) translateY(4px); }
  100% { transform: translateX(-50%) translateY(0); }
}

@keyframes scorePop {
  0% { transform: scale(1); }
  50% { transform: scale(1.3); }
  100% { transform: scale(1); }
}

@keyframes scoreFloatScale {
  0% { transform: translateY(10px) scale(0.5); opacity: 0; }
  40% { transform: translateY(-8px) scale(1.15); opacity: 1; }
  100% { transform: translateY(0) scale(1); opacity: 1; }
}

@keyframes comboPop {
  0% { transform: scale(0.5); opacity: 0; }
  60% { transform: scale(1.2); }
  100% { transform: scale(1); opacity: 1; }
}

@keyframes comboFire {
  0%, 100% { color: var(--error); text-shadow: 0 0 4px rgba(217,64,64,0.3); }
  50% { color: var(--am); text-shadow: 0 0 12px rgba(184,134,11,0.5); }
}

@keyframes rosterSlideIn {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes optionReveal {
  from { opacity: 0; transform: translateX(16px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes failShake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-4px); }
  40% { transform: translateX(4px); }
  60% { transform: translateX(-3px); }
  80% { transform: translateX(3px); }
}

@keyframes screenFlash {
  0% { opacity: 1; }
  100% { opacity: 0; }
}

@keyframes starBurst {
  0% { transform: translate(0, 0) scale(0); opacity: 1; }
  100% { transform: translate(var(--bx), var(--by)) scale(1.2); opacity: 0; }
}

@keyframes feedbackSlideUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes waveSpin {
  0% { transform: rotate(0deg) scale(0.5); opacity: 0; }
  60% { transform: rotate(360deg) scale(1.1); opacity: 1; }
  100% { transform: rotate(360deg) scale(1); opacity: 1; }
}

@keyframes waveAnnounce {
  0% { transform: scale(0.8); opacity: 0; }
  60% { transform: scale(1.05); }
  100% { transform: scale(1); opacity: 1; }
}

@keyframes waveTensePulse {
  0% { box-shadow: none; }
  50% { box-shadow: inset 0 0 60px rgba(217,64,64,0.06); }
  100% { box-shadow: none; }
}

@keyframes confettiFall {
  0% { transform: translateY(0) rotate(0deg); opacity: 1; }
  100% { transform: translateY(100vh) rotate(720deg); opacity: 0; }
}

/* 设计系统特效动画 */
@keyframes shimmer {
  0% { background-position: 200% center; }
  100% { background-position: -200% center; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

@keyframes glowSpin { to { transform: rotate(360deg); } }

@keyframes pulse {
  0%, 100% { filter: brightness(1); }
  50% { filter: brightness(1.3); }
}

@keyframes spin { to { transform: rotate(360deg); } }

@keyframes dotBounce {
  0%, 80%, 100% { transform: translateY(0); opacity: 0.3; }
  40% { transform: translateY(-6px); opacity: 1; }
}

@keyframes genPulse {
  0%, 100% { opacity: 0.5; transform: scale(1); }
  50% { opacity: 0.9; transform: scale(1.05); }
}

@keyframes handWave {
  0% { transform: rotate(0deg); }
  15% { transform: rotate(14deg); }
  30% { transform: rotate(-8deg); }
  45% { transform: rotate(10deg); }
  60% { transform: rotate(-4deg); }
  75% { transform: rotate(4deg); }
  100% { transform: rotate(0deg); }
}

/* ================================================
   响应式
   ================================================ */
@media (max-width: 640px) {
  .welcome-title { font-size: 2.6rem; }
  .welcome-subtitle { font-size: var(--text-lg); }
  .welcome-actions { width: 100%; }
  .welcome-actions .btn-primary { width: 100%; min-width: 0; justify-content: center; }

  .generating-students { gap: var(--space-3); }
  .gen-student-avatar { width: 36px; height: 36px; }

  .scenario-card { flex-direction: column; align-items: flex-start; }
  .scenario-arrow { display: none; }

  .hud { flex-direction: column; gap: var(--space-2); }
  .hud-left, .hud-right { width: 100%; }
  .hud-right { flex-direction: row; justify-content: space-between; align-items: center; }

  .result-stats { grid-template-columns: repeat(2, 1fr); }

  .result-round { flex-wrap: wrap; }
  .rr-question { min-width: 100%; order: 10; }

  .question-header { flex-direction: column; align-items: flex-start; }
  .question-meta { flex-wrap: wrap; }

  .intro-vs { font-size: 1.8rem; }
  .intro-avatar { width: 60px; height: 60px; font-size: 1.6rem; }
  .intro-avatar-ring { width: 60px; height: 60px; }
  .round-intro { gap: var(--space-4); padding: var(--space-8) 10px; }

  .result-actions { flex-direction: column; }
  .result-actions button { width: 100%; justify-content: center; }

  .perf-card {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-2);
  }
  .perf-bar-container { width: 100%; }
  .perf-stat { text-align: left; min-width: auto; }

  .suggestion-card { flex-direction: column; gap: var(--space-2); }

  .audio-toggle { margin-left: auto; }
  .hud-bottom { flex-direction: column; gap: 0; }
}

/* ================================================
   课堂场景氛围
   ================================================ */
.battle-screen {
  position: relative;
}

.battle-screen::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 35vh;
  background: linear-gradient(180deg, rgba(42,122,110,0.06) 0%, transparent 100%);
  pointer-events: none;
  z-index: 0;
}

.battle-screen > * {
  position: relative;
  z-index: 1;
}

.battle-divider {
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(196,93,62,0.3), transparent);
  margin: var(--space-2) 0 10px;
  border-radius: 2px;
}

.hud-bottom {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-bottom: var(--space-1);
}

.hud-bottom .battle-content {
  margin-bottom: 0;
}

.audio-toggle {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bc);
  border: 1px solid var(--bd);
  border-radius: var(--radius-sm);
  color: var(--txt);
  font-size: var(--text-sm);
  transition: var(--transition-fast);
  cursor: pointer;
  flex-shrink: 0;
}
.audio-toggle:hover {
  border-color: var(--ac);
  color: var(--ac);
}

.bubble-hand {
  position: absolute;
  top: -12px;
  right: var(--space-4);
  font-size: var(--text-xl);
  animation: handWave 1.5s ease-in-out;
  transform-origin: bottom center;
}

/* ================================================
   Loading + 屏幕过渡 + 触摸反馈
   ================================================ */
.loading-screen {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-4);
}

.loading-spinner {
  width: 36px;
  height: 36px;
  border: 3px solid var(--bd);
  border-top-color: var(--ac);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
}

.loading-text {
  color: var(--txt);
  font-size: var(--text-md);
}

.screen-phase-battle {
  background: linear-gradient(180deg, var(--bg), var(--bgs));
  transition: background 0.5s ease;
}

.screen-phase-result {
  background: linear-gradient(180deg, var(--bg), var(--bge));
  transition: background 0.5s ease;
}

/* 触摸反馈 */
.option-card:active {
  transform: scale(0.98) translateX(4px);
  transition: transform 0.1s ease;
}

.btn-primary:active {
  transform: scale(0.97);
  transition: transform 0.1s ease;
}

.btn-next:active {
  transform: scale(0.97);
  transition: transform 0.1s ease;
}