/* ===== 全局重置 & 变量 ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0f0f1a;
  --card-bg: #1a1a2e;
  --panel-bg: #16213e;
  --accent: #e94560;
  --accent2: #0f3460;
  --green: #4ecca3;
  --yellow: #f7d716;
  --text: #e0e0e0;
  --text-dim: #888;
  --correct: #4ecca3;
  --wrong: #e94560;
  --current: #f7d716;
  --radius: 12px;
  --shadow: 0 8px 32px rgba(0,0,0,0.5);
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 0 16px 40px;
}

/* ===== 头部 ===== */
header {
  text-align: center;
  padding: 40px 0 20px;
}

header h1 {
  font-size: 2.4rem;
  background: linear-gradient(135deg, var(--accent), var(--green));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: 2px;
  margin-bottom: 8px;
}

.subtitle {
  color: var(--text-dim);
  font-size: 1rem;
}

/* ===== 主区域 ===== */
main {
  width: 100%;
  max-width: 860px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* ===== 难度选择 ===== */
.difficulty-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--card-bg);
  padding: 12px 20px;
  border-radius: var(--radius);
}

.difficulty-bar span {
  color: var(--text-dim);
  font-size: 0.95rem;
}

.diff-btn {
  padding: 6px 18px;
  border: 2px solid transparent;
  border-radius: 20px;
  background: var(--panel-bg);
  color: var(--text-dim);
  cursor: pointer;
  font-size: 0.88rem;
  transition: all 0.2s;
}

.diff-btn:hover {
  border-color: var(--accent);
  color: var(--text);
}

.diff-btn.active {
  border-color: var(--green);
  color: var(--green);
  background: rgba(78, 204, 163, 0.1);
}

/* ===== 统计面板 ===== */
.stats-panel {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}

.stat-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 18px 10px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255,255,255,0.05);
  transition: transform 0.2s;
}

.stat-card:hover {
  transform: translateY(-2px);
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  color: var(--green);
  line-height: 1;
  margin-bottom: 6px;
  transition: color 0.3s;
}

.stat-label {
  font-size: 0.78rem;
  color: var(--text-dim);
  letter-spacing: 1px;
}

/* ===== 进度条 ===== */
.progress-wrap {
  height: 6px;
  background: var(--panel-bg);
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--green), var(--accent));
  border-radius: 3px;
  transition: width 0.3s ease;
}

/* ===== 文字展示区 ===== */
.text-display {
  background: var(--card-bg);
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: var(--radius);
  padding: 28px 32px;
  font-size: 1.25rem;
  line-height: 2;
  letter-spacing: 0.5px;
  min-height: 120px;
  word-break: break-all;
  box-shadow: var(--shadow);
  position: relative;
  user-select: none;
}

/* 字符状态颜色 */
.text-display .char {
  display: inline;
  transition: color 0.1s, background 0.1s;
}

.char.correct {
  color: var(--correct);
}

.char.wrong {
  color: var(--wrong);
  background: rgba(233, 69, 96, 0.15);
  border-radius: 2px;
}

.char.current {
  color: var(--current);
  border-bottom: 2px solid var(--current);
  animation: blink 0.8s infinite;
}

@keyframes blink {
  0%, 100% { border-color: var(--current); }
  50% { border-color: transparent; }
}

/* ===== 输入框 ===== */
.input-wrap {
  position: relative;
}

#inputBox {
  width: 100%;
  min-height: 100px;
  background: var(--card-bg);
  border: 2px solid rgba(255,255,255,0.08);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 1.1rem;
  padding: 18px 20px;
  resize: none;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
  font-family: 'Consolas', 'Courier New', monospace;
  line-height: 1.7;
}

#inputBox:focus {
  border-color: var(--green);
  box-shadow: 0 0 0 3px rgba(78, 204, 163, 0.15);
}

#inputBox:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ===== 按钮组 ===== */
.btn-group {
  display: flex;
  gap: 14px;
  justify-content: center;
}

.btn {
  padding: 12px 36px;
  border: none;
  border-radius: 30px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  letter-spacing: 0.5px;
}

.btn-start {
  background: linear-gradient(135deg, var(--accent), #c0392b);
  color: #fff;
  box-shadow: 0 4px 20px rgba(233, 69, 96, 0.4);
}

.btn-start:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 24px rgba(233, 69, 96, 0.6);
}

.btn-reset {
  background: var(--card-bg);
  color: var(--text-dim);
  border: 2px solid rgba(255,255,255,0.1);
}

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

/* ===== 结果弹窗 ===== */
.result-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 999;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.result-overlay.show {
  opacity: 1;
  pointer-events: all;
}

.result-card {
  background: var(--card-bg);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 20px;
  padding: 40px 50px;
  text-align: center;
  max-width: 500px;
  width: 90%;
  box-shadow: 0 20px 60px rgba(0,0,0,0.6);
  transform: scale(0.8);
  transition: transform 0.3s;
}

.result-overlay.show .result-card {
  transform: scale(1);
}

.result-emoji {
  font-size: 4rem;
  margin-bottom: 12px;
}

.result-card h2 {
  font-size: 1.8rem;
  color: var(--green);
  margin-bottom: 24px;
}

.result-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 24px;
}

.r-item {
  background: var(--panel-bg);
  border-radius: 10px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.r-label {
  font-size: 0.78rem;
  color: var(--text-dim);
}

.r-val {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--accent);
}

.r-unit {
  font-size: 0.8rem;
  color: var(--text-dim);
}

.rank-badge {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 24px;
  padding: 10px 24px;
  border-radius: 30px;
  display: inline-block;
}

/* ===== 历史记录 ===== */
.history-section {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 24px;
  border: 1px solid rgba(255,255,255,0.05);
}

.history-section h3 {
  margin-bottom: 16px;
  color: var(--text);
  font-size: 1rem;
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.no-record {
  color: var(--text-dim);
  text-align: center;
  padding: 16px;
  font-size: 0.9rem;
}

.history-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--panel-bg);
  border-radius: 8px;
  padding: 12px 16px;
  font-size: 0.9rem;
  animation: slideIn 0.3s ease;
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(-10px); }
  to { opacity: 1; transform: translateX(0); }
}

.h-rank {
  font-size: 1.2rem;
}

.h-wpm {
  color: var(--green);
  font-weight: 700;
  font-size: 1.1rem;
}

.h-info {
  color: var(--text-dim);
  font-size: 0.82rem;
}

/* ===== 底部 ===== */
footer {
  margin-top: 30px;
  color: var(--text-dim);
  font-size: 0.85rem;
  text-align: center;
}

/* ===== 响应式 ===== */
@media (max-width: 600px) {
  header h1 { font-size: 1.6rem; }
  .stats-panel { grid-template-columns: repeat(2, 1fr); }
  .text-display { font-size: 1rem; padding: 18px; }
  .result-card { padding: 28px 24px; }
  .result-stats { grid-template-columns: 1fr 1fr; }
  .difficulty-bar { flex-wrap: wrap; }
}

/* ===== 闪烁连击效果 ===== */
.combo-flash {
  animation: comboFlash 0.3s ease;
}

@keyframes comboFlash {
  0% { color: var(--green); transform: scale(1.3); }
  100% { color: var(--green); transform: scale(1); }
}