/* ============ CMCM HACKATHON 赛博朋克风格 - 性能优化版 ============ */
:root {
  --bg-dark: #050508;
  --bg-card: #0a0a12;
  --bg-card-hover: #12121f;
  --neon-green: #00ff88;
  --neon-cyan: #00f0ff;
  --neon-pink: #ff00ff;
  --neon-yellow: #ffdd00;
  --neon-orange: #ff6600;
  --neon-purple: #9d00ff;
  --text-primary: #f0f0f0;
  --text-secondary: #8899aa;
  --border-color: #1a1a2e;
  --glow-green: 0 0 10px #00ff88, 0 0 20px #00ff8844;
  --glow-cyan: 0 0 10px #00f0ff, 0 0 20px #00f0ff44;
  --glow-pink: 0 0 10px #ff00ff, 0 0 20px #ff00ff44;
  --font-main: 'Segoe UI', 'Microsoft YaHei', 'PingFang SC', sans-serif;
  --font-mono: 'Consolas', 'Monaco', 'Courier New', monospace;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-main);
  background: var(--bg-dark);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
  line-height: 1.6;
}

/* 静态渐变背景 (性能优化：移除动画) */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    radial-gradient(ellipse at 15% 15%, rgba(0, 255, 136, 0.12) 0%, transparent 50%),
    radial-gradient(ellipse at 85% 85%, rgba(0, 240, 255, 0.10) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 50%, rgba(157, 0, 255, 0.06) 0%, transparent 60%);
  pointer-events: none;
  z-index: -2;
}

/* 网格背景 (静态，性能优化) */
body::after {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background:
    linear-gradient(90deg, rgba(0,255,136,0.03) 1px, transparent 1px),
    linear-gradient(rgba(0,255,136,0.03) 1px, transparent 1px);
  background-size: 80px 80px;
  pointer-events: none;
  z-index: -1;
}

/* 扫描线效果 (GPU加速) */
.scanline {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent 20%, var(--neon-green) 50%, transparent 80%);
  opacity: 0.4;
  z-index: 9999;
  pointer-events: none;
  will-change: transform;
  animation: scanline 5s linear infinite;
}

@keyframes scanline {
  0% { transform: translateY(-10px); }
  100% { transform: translateY(100vh); }
}

/* 粒子动画容器 */
.particles {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: -1;
  overflow: hidden;
  font-family: 'Courier New', monospace;
}

/* 黑客帝国数字雨 */
.matrix-column {
  position: absolute;
  top: -100%;
  display: flex;
  flex-direction: column;
  font-size: 12px;
  line-height: 1.1;
  color: #00ff41;
  text-shadow: 0 0 5px #00ff41;
  will-change: transform;
  animation: matrixFall linear forwards;
  font-weight: bold;
  letter-spacing: 0;
}

.matrix-column span {
  display: block;
  opacity: 0.8;
}

.matrix-column span:first-child {
  color: #ffffff;
  text-shadow: 0 0 15px #00ff41, 0 0 30px #00ff41, 0 0 45px #00ff41;
  opacity: 1;
}

@keyframes matrixFall {
  0% {
    transform: translateY(0);
  }
  100% {
    transform: translateY(calc(200vh + 100%));
  }
}

/* ============ 通用组件 ============ */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px;
  position: relative;
}

.header {
  text-align: center;
  padding: 30px 20px 40px;
  margin-bottom: 20px;
  position: relative;
}

.header::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 500px;
  height: 150px;
  background: radial-gradient(ellipse, rgba(0, 255, 136, 0.2) 0%, transparent 70%);
  pointer-events: none;
  filter: blur(30px);
}

.header h1 {
  font-size: 2.8rem;
  font-weight: 800;
  color: var(--neon-green);
  text-shadow: var(--glow-green);
  letter-spacing: 6px;
  text-transform: uppercase;
  position: relative;
  font-family: var(--font-mono);
}

.header .subtitle {
  color: var(--text-secondary);
  margin-top: 15px;
  font-size: 1.1rem;
  letter-spacing: 2px;
  font-weight: 500;
}

/* 按钮 (简化动画) */
.btn {
  padding: 14px 28px;
  border: 2px solid var(--neon-green);
  background: transparent;
  color: var(--neon-green);
  font-family: var(--font-main);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.25s ease;
  text-transform: uppercase;
  letter-spacing: 2px;
  position: relative;
  overflow: hidden;
}

.btn:hover {
  background: var(--neon-green);
  color: var(--bg-dark);
  box-shadow: var(--glow-green);
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--neon-green), #00cc66);
  color: var(--bg-dark);
  border: none;
}

.btn-primary:hover {
  background: linear-gradient(135deg, #00ff99, var(--neon-green));
  box-shadow: var(--glow-green);
}

.btn-danger {
  border-color: #ff4455;
  color: #ff4455;
}

.btn-danger:hover {
  background: #ff4455;
  color: var(--bg-dark);
  box-shadow: 0 0 15px #ff445566;
}

.btn-success {
  border-color: var(--neon-green);
  color: var(--neon-green);
}

.btn-success:hover {
  background: var(--neon-green);
  color: var(--bg-dark);
}

/* 输入框 */
.input {
  width: 100%;
  padding: 16px 20px;
  border: 2px solid var(--border-color);
  background: rgba(10, 10, 18, 0.9);
  color: var(--text-primary);
  font-family: var(--font-main);
  font-size: 1rem;
  transition: all 0.25s ease;
  border-radius: 4px;
}

.input:focus {
  outline: none;
  border-color: var(--neon-cyan);
  box-shadow: 0 0 15px rgba(0, 240, 255, 0.3);
}

.input::placeholder {
  color: var(--text-secondary);
}

/* 卡片 */
.card {
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(20, 20, 35, 0.95));
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 25px;
  margin-bottom: 15px;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--neon-cyan), transparent);
  opacity: 0;
  transition: opacity 0.3s;
}

.card:hover::before {
  opacity: 1;
}

.card:hover {
  border-color: rgba(0, 240, 255, 0.5);
  transform: translateY(-3px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
}

/* ============ 登录页 ============ */
.login-container {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 20px;
}

.login-box {
  width: 100%;
  max-width: 420px;
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.98), rgba(15, 15, 30, 0.98));
  border: 2px solid var(--neon-green);
  border-radius: 12px;
  padding: 50px 40px;
  box-shadow: var(--glow-green), 0 20px 60px rgba(0, 0, 0, 0.5);
  position: relative;
}

.login-box h1 {
  text-align: center;
  color: var(--neon-green);
  margin-bottom: 40px;
  font-size: 1.6rem;
  text-shadow: var(--glow-green);
  font-family: var(--font-mono);
  letter-spacing: 3px;
}

.login-box .form-group {
  margin-bottom: 25px;
}

.login-box label {
  display: block;
  margin-bottom: 10px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 2px;
  font-weight: 600;
}

.login-box .btn {
  width: 100%;
  margin-top: 15px;
  padding: 16px;
  font-size: 1.1rem;
}

.login-box .tips {
  margin-top: 30px;
  padding-top: 25px;
  border-top: 1px solid var(--border-color);
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.login-box .tips p {
  margin: 10px 0;
}

.error-msg {
  color: #ff4455;
  font-size: 0.9rem;
  margin-top: 15px;
  text-align: center;
}

/* ============ 统计面板 ============ */
.stats-panel {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 40px;
}

.stats-panel .card {
  text-align: center;
  padding: 30px 20px;
}

.stats-panel .card .value {
  font-size: 2.8rem;
  font-weight: 800;
  margin-bottom: 10px;
  font-family: var(--font-mono);
}

.stats-panel .card .label {
  color: var(--text-secondary);
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 3px;
  font-weight: 600;
}

.stats-panel .card:nth-child(1) .value { color: var(--neon-green); text-shadow: var(--glow-green); }
.stats-panel .card:nth-child(2) .value { color: var(--neon-cyan); text-shadow: var(--glow-cyan); }
.stats-panel .card:nth-child(3) .value { color: var(--neon-pink); text-shadow: var(--glow-pink); }
.stats-panel .card:nth-child(4) .value { color: var(--neon-yellow); text-shadow: 0 0 10px var(--neon-yellow); }

/* ============ 主看板排行榜 ============ */
.leaderboard {
  background: linear-gradient(180deg, rgba(10, 10, 18, 0.95), rgba(5, 5, 10, 0.98));
  border: 1px solid rgba(0, 255, 136, 0.3);
  border-radius: 16px;
  overflow: hidden;
  max-width: 1000px;
  margin: 0 auto;
  box-shadow: 0 0 60px rgba(0, 255, 136, 0.1), 0 0 100px rgba(0, 0, 0, 0.5);
  position: relative;
}

.leaderboard::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--neon-green), transparent);
}

.leaderboard-header {
  display: grid;
  grid-template-columns: 120px 160px 1fr 160px;
  padding: 25px 50px;
  background: linear-gradient(180deg, rgba(0, 255, 136, 0.12), rgba(0, 255, 136, 0.03));
  border-bottom: 2px solid rgba(0, 255, 136, 0.25);
  font-size: 1.1rem;
  color: var(--neon-green);
  text-transform: uppercase;
  letter-spacing: 4px;
  font-weight: 700;
  text-align: center;
  font-family: var(--font-mono);
  text-shadow: 0 0 10px rgba(0, 255, 136, 0.5);
}

.leaderboard-row {
  display: grid;
  grid-template-columns: 120px 160px 1fr 160px;
  padding: 22px 50px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
  transition: all 0.3s ease;
  align-items: center;
  text-align: center;
  position: relative;
}

.leaderboard-row::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 100%;
  background: transparent;
  transition: background 0.3s;
}

.leaderboard-row:hover {
  background: linear-gradient(90deg, rgba(0, 255, 136, 0.1), rgba(0, 255, 136, 0.02));
}

.leaderboard-row:hover::before {
  background: var(--neon-green);
  box-shadow: 0 0 20px var(--neon-green);
}

.leaderboard-row:last-child {
  border-bottom: none;
}

.rank {
  font-size: 2rem;
  font-weight: 900;
  font-style: italic;
  text-align: center;
  font-family: var(--font-mono);
}

.rank-1 {
  color: #ffd700;
  text-shadow: 0 0 20px #ffd700, 0 0 40px #ffd70066;
  font-size: 2.3rem;
}

.rank-2 {
  color: #c0c0c0;
  text-shadow: 0 0 15px #c0c0c0, 0 0 30px #c0c0c066;
  font-size: 2.1rem;
}

.rank-3 {
  color: #cd7f32;
  text-shadow: 0 0 15px #cd7f32, 0 0 30px #cd7f3266;
  font-size: 2rem;
}

.player-number {
  color: var(--neon-cyan);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.3rem;
  text-align: center;
  text-shadow: 0 0 10px rgba(0, 240, 255, 0.5);
}

.player-name {
  color: var(--text-primary);
  font-size: 1.4rem;
  letter-spacing: 2px;
  text-align: center;
  font-weight: 600;
}

.player-score {
  font-size: 2.4rem;
  color: var(--neon-green);
  text-shadow: var(--glow-green);
  font-weight: 800;
  text-align: center;
  font-family: var(--font-mono);
}

/* ============ 弹幕 ============ */
.danmaku-container {
  position: fixed;
  top: 100px;
  left: 0;
  width: 100%;
  height: 200px;
  pointer-events: none;
  overflow: hidden;
  z-index: 1000;
}

.danmaku {
  position: absolute;
  white-space: nowrap;
  font-size: 1.2rem;
  font-weight: 700;
  padding: 10px 24px;
  background: rgba(0, 0, 0, 0.7);
  border-radius: 30px;
  border: 1px solid;
  will-change: transform;
  animation: danmaku-move 8s linear forwards;
}

@keyframes danmaku-move {
  from { transform: translateX(100vw); }
  to { transform: translateX(-100%); }
}

/* ============ 选手页面 ============ */
.player-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 30px 40px;
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(0, 240, 255, 0.08));
  border: 2px solid var(--neon-cyan);
  border-radius: 12px;
  margin-bottom: 30px;
  box-shadow: var(--glow-cyan);
}

.player-info .number {
  font-size: 2.5rem;
  color: var(--neon-cyan);
  text-shadow: var(--glow-cyan);
  font-weight: 800;
  font-family: var(--font-mono);
}

.player-info .score {
  font-size: 3rem;
  color: var(--neon-green);
  text-shadow: var(--glow-green);
  font-weight: 800;
  font-family: var(--font-mono);
}

.problems-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}

.problem-card {
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(15, 15, 30, 0.95));
  border: 2px solid var(--border-color);
  border-radius: 10px;
  padding: 25px;
  transition: all 0.3s ease;
  cursor: pointer;
  position: relative;
}

.problem-card:hover {
  border-color: var(--neon-cyan);
  transform: translateY(-4px);
  box-shadow: 0 10px 35px rgba(0, 240, 255, 0.15);
}

.problem-card.completed {
  border-color: var(--neon-orange);
  background: linear-gradient(135deg, rgba(255, 102, 0, 0.12), rgba(10, 10, 18, 0.95));
}

.problem-card.scored {
  border-color: var(--neon-green);
  background: linear-gradient(135deg, rgba(0, 255, 136, 0.12), rgba(10, 10, 18, 0.95));
}

.problem-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 15px;
}

.problem-number {
  font-size: 1.3rem;
  color: var(--neon-cyan);
  font-weight: 700;
  font-family: var(--font-mono);
}

.problem-score {
  font-size: 1.2rem;
  color: var(--neon-yellow);
  font-weight: 700;
  font-family: var(--font-mono);
}

.problem-title {
  color: var(--text-secondary);
  font-size: 1rem;
}

.problem-status {
  margin-top: 20px;
  padding-top: 18px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.status-tag {
  padding: 6px 16px;
  font-size: 0.8rem;
  text-transform: uppercase;
  border: 2px solid;
  border-radius: 4px;
  font-weight: 700;
  letter-spacing: 1px;
}

.status-pending {
  border-color: var(--text-secondary);
  color: var(--text-secondary);
}

.status-completed {
  border-color: var(--neon-orange);
  color: var(--neon-orange);
}

.status-scored {
  border-color: var(--neon-green);
  color: var(--neon-green);
  background: rgba(0, 255, 136, 0.1);
}

.status-rejected {
  border-color: #ff4444;
  color: #ff4444;
  background: rgba(255, 68, 68, 0.15);
  animation: rejectPulse 1s ease-in-out infinite;
}

@keyframes rejectPulse {
  0%, 100% { box-shadow: 0 0 5px rgba(255, 68, 68, 0.5); }
  50% { box-shadow: 0 0 15px rgba(255, 68, 68, 0.8); }
}

.problem-card.rejected {
  border-color: #ff4444;
  background: linear-gradient(135deg, rgba(255, 68, 68, 0.15), rgba(10, 10, 18, 0.95));
  animation: rejectCardPulse 2s ease-in-out infinite;
}

@keyframes rejectCardPulse {
  0%, 100% { box-shadow: 0 0 10px rgba(255, 68, 68, 0.3); }
  50% { box-shadow: 0 0 25px rgba(255, 68, 68, 0.6); }
}

/* ============ 导师后台 ============ */
.mentor-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 30px 40px;
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(255, 0, 255, 0.08));
  border: 2px solid var(--neon-pink);
  border-radius: 12px;
  margin-bottom: 30px;
  box-shadow: var(--glow-pink);
}

.mentor-info .name {
  font-size: 2rem;
  color: var(--neon-pink);
  text-shadow: var(--glow-pink);
  font-weight: 700;
}

.mentor-info .range {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

/* 超管面板 */
.admin-panel {
  background: linear-gradient(135deg, rgba(255, 68, 68, 0.1), rgba(10, 10, 18, 0.95));
  border: 2px solid #ff4444;
  border-radius: 12px;
  padding: 20px 30px;
  margin-bottom: 30px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: 0 0 20px rgba(255, 68, 68, 0.2);
}

.admin-panel-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: #ff6666;
}

.admin-reset-btn {
  padding: 12px 24px;
  font-size: 1rem;
  background: rgba(255, 68, 68, 0.2);
  border: 2px solid #ff4444;
  color: #ff6666;
}

.admin-reset-btn:hover {
  background: #ff4444;
  color: #fff;
  box-shadow: 0 0 30px rgba(255, 68, 68, 0.5);
}

.admin-panel-container {
  display: flex;
  gap: 20px;
  margin-bottom: 30px;
  flex-wrap: wrap;
}

.admin-panel-container .admin-panel {
  flex: 1;
  min-width: 300px;
  margin-bottom: 0;
}

.timer-panel {
  background: linear-gradient(135deg, rgba(0, 255, 136, 0.1), rgba(10, 10, 18, 0.95)) !important;
  border-color: var(--neon-green) !important;
  box-shadow: 0 0 20px rgba(0, 255, 136, 0.2) !important;
}

.timer-panel .admin-panel-title {
  color: var(--neon-green) !important;
}

.timer-form {
  display: flex;
  gap: 15px;
  align-items: center;
  flex-wrap: wrap;
}

.timer-input {
  padding: 10px 15px;
  font-size: 1rem;
  background: rgba(0, 0, 0, 0.5);
  border: 2px solid var(--neon-green);
  border-radius: 6px;
  color: var(--text-primary);
  font-family: var(--font-mono);
}

.timer-input:focus {
  outline: none;
  box-shadow: 0 0 15px rgba(0, 255, 136, 0.4);
}

.current-endtime {
  margin-top: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.players-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 25px;
}

.player-card {
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(15, 15, 30, 0.95));
  border: 2px solid var(--border-color);
  border-radius: 10px;
  padding: 25px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.player-card:hover {
  border-color: var(--neon-cyan);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 240, 255, 0.12);
}

.player-card.active {
  border-color: var(--neon-green);
  box-shadow: var(--glow-green);
}

.player-card.has-pending {
  border-color: var(--neon-orange);
  background: linear-gradient(135deg, rgba(255, 102, 0, 0.15), rgba(10, 10, 18, 0.95));
  animation: pendingPulse 2s ease-in-out infinite;
}

@keyframes pendingPulse {
  0%, 100% { box-shadow: 0 0 10px rgba(255, 102, 0, 0.3); }
  50% { box-shadow: 0 0 25px rgba(255, 102, 0, 0.6); }
}

.player-card-header {
  display: flex;
  justify-content: space-between;
  margin-bottom: 15px;
}

.player-card-number {
  font-size: 1.4rem;
  color: var(--neon-cyan);
  font-weight: 700;
  font-family: var(--font-mono);
}

.player-card-score {
  font-size: 1.4rem;
  color: var(--neon-green);
  font-weight: 700;
  font-family: var(--font-mono);
}

.player-card-progress {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-top: 15px;
}

.progress-bar {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 3px;
  overflow: hidden;
  margin-top: 10px;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--neon-green), var(--neon-cyan));
  transition: width 0.6s ease;
  border-radius: 3px;
}

/* 模态框 */
.modal-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.9);
  z-index: 2000;
  justify-content: center;
  align-items: center;
  backdrop-filter: blur(8px);
}

.modal-overlay.active {
  display: flex;
}

.modal {
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.99), rgba(15, 15, 30, 0.99));
  border: 2px solid var(--neon-cyan);
  border-radius: 12px;
  padding: 40px;
  max-width: 850px;
  width: 95%;
  max-height: 85vh;
  overflow-y: auto;
  box-shadow: var(--glow-cyan), 0 30px 80px rgba(0, 0, 0, 0.7);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-color);
}

.modal-title {
  font-size: 1.4rem;
  color: var(--neon-cyan);
  font-weight: 700;
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 2rem;
  cursor: pointer;
  transition: all 0.3s;
  line-height: 1;
}

.modal-close:hover {
  color: #ff4455;
  transform: rotate(90deg);
}

.submission-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  margin-bottom: 15px;
  transition: all 0.3s ease;
  background: rgba(0, 0, 0, 0.2);
}

.submission-item:hover {
  background: rgba(0, 240, 255, 0.05);
  border-color: rgba(0, 240, 255, 0.3);
}

.submission-item.pending {
  opacity: 0.4;
}

.submission-info {
  flex: 1;
}

.submission-actions {
  display: flex;
  gap: 15px;
}

.submission-actions .btn {
  padding: 10px 20px;
  font-size: 0.9rem;
}

/* ============ 响应式 ============ */
@media (max-width: 768px) {
  .header h1 {
    font-size: 1.6rem;
    letter-spacing: 3px;
  }

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

  .stats-panel .card .value {
    font-size: 2rem;
  }

  .leaderboard-header,
  .leaderboard-row {
    grid-template-columns: 60px 80px 1fr 80px;
    font-size: 0.85rem;
    padding: 14px 20px;
  }

  .rank { font-size: 1.3rem; }
  .player-score { font-size: 1.4rem; }

  .problems-grid,
  .players-list {
    grid-template-columns: 1fr;
  }

  .player-info,
  .mentor-info {
    flex-direction: column;
    gap: 20px;
    text-align: center;
  }

  .top-login-btn {
    font-size: 0.9rem;
    padding: 8px 16px;
  }
}

/* ============ 动画效果 ============ */
.score-animate {
  animation: scoreUp 0.5s ease;
}

@keyframes scoreUp {
  0% { transform: scale(1); }
  50% { transform: scale(1.2); color: var(--neon-yellow); }
  100% { transform: scale(1); }
}

.rank-up {
  animation: rankUp 0.5s ease;
}

@keyframes rankUp {
  0% { transform: translateY(20px); opacity: 0; }
  100% { transform: translateY(0); opacity: 1; }
}

/* 加载动画 */
.loading {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 50px;
}

.loading::after {
  content: '';
  width: 40px;
  height: 40px;
  border: 3px solid var(--border-color);
  border-top-color: var(--neon-green);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* 右上角登录/退出按钮 */
.logout-btn,
.top-login-btn {
  position: fixed;
  top: 25px;
  right: 25px;
  z-index: 100;
  padding: 14px 28px;
  font-size: 1.1rem;
  font-weight: 700;
  color: #000000;
  text-decoration: none;
  border: none;
  border-radius: 6px;
  background: #00ff41;
  box-shadow: 0 0 20px rgba(0, 255, 65, 0.4), 0 0 40px rgba(0, 255, 65, 0.2);
  transition: all 0.3s ease;
  letter-spacing: 2px;
}

.top-login-btn:hover,
.logout-btn:hover {
  background: #00cc33;
  color: #000000;
  box-shadow: 0 0 30px rgba(0, 255, 65, 0.6), 0 0 60px rgba(0, 255, 65, 0.3);
  transform: translateY(-2px);
}

/* 角落装饰 */
.corner-decoration {
  position: fixed;
  width: 80px;
  height: 80px;
  border: 2px solid var(--neon-green);
  opacity: 0.25;
  pointer-events: none;
}

.corner-decoration.top-left {
  top: 15px;
  left: 15px;
  border-right: none;
  border-bottom: none;
}

.corner-decoration.top-right {
  top: 15px;
  right: 15px;
  border-left: none;
  border-bottom: none;
}

.corner-decoration.bottom-left {
  bottom: 15px;
  left: 15px;
  border-right: none;
  border-top: none;
}

.corner-decoration.bottom-right {
  bottom: 15px;
  right: 15px;
  border-left: none;
  border-top: none;
}

/* 倒计时面板 */
.countdown-panel {
  position: fixed;
  top: 80px;
  left: 30px;
  background: linear-gradient(135deg, rgba(10, 10, 18, 0.95), rgba(0, 255, 136, 0.1));
  border: 2px solid var(--neon-green);
  border-radius: 12px;
  padding: 20px 30px;
  text-align: center;
  z-index: 100;
  box-shadow: var(--glow-green);
  min-width: 180px;
}

.countdown-title {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 10px;
  letter-spacing: 2px;
}

.countdown-timer {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--neon-green);
  text-shadow: 0 0 20px rgba(0, 255, 136, 0.5);
  letter-spacing: 3px;
}

.countdown-timer.warning {
  color: var(--neon-orange);
  text-shadow: 0 0 20px rgba(255, 102, 0, 0.5);
  animation: timerPulse 1s ease-in-out infinite;
}

.countdown-timer.ended {
  color: #ff4444;
  text-shadow: 0 0 20px rgba(255, 68, 68, 0.5);
}

@keyframes timerPulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

.countdown-status {
  font-size: 0.85rem;
  margin-top: 8px;
  color: var(--text-secondary);
}

/* 退回通知弹窗 */
.reject-notification {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: linear-gradient(135deg, rgba(20, 10, 10, 0.98), rgba(80, 20, 20, 0.95));
  border: 3px solid #ff4444;
  border-radius: 16px;
  padding: 40px 50px;
  text-align: center;
  z-index: 10000;
  box-shadow: 0 0 50px rgba(255, 68, 68, 0.5), 0 0 100px rgba(255, 68, 68, 0.3);
  animation: rejectNotifyIn 0.3s ease-out;
}

@keyframes rejectNotifyIn {
  from {
    opacity: 0;
    transform: translate(-50%, -50%) scale(0.8);
  }
  to {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
  }
}

.reject-notification .reject-icon {
  font-size: 4rem;
  margin-bottom: 20px;
  animation: shake 0.5s ease-in-out;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-10px); }
  40%, 80% { transform: translateX(10px); }
}

.reject-notification .reject-message {
  font-size: 1.5rem;
  color: #ff6666;
  margin-bottom: 30px;
  font-weight: 700;
}

.reject-notification button {
  padding: 12px 40px;
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
  background: #ff4444;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.3s ease;
}

.reject-notification button:hover {
  background: #ff6666;
  box-shadow: 0 0 20px rgba(255, 68, 68, 0.6);
}