/* 揭榜挂帅页面样式 */
*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}

/* 页面容器 */
.challenge-page{
  min-height:100vh;
  background:var(--bg);
  padding-top:56px;
}

/* 头部区域 */
.challenge-hero{
  padding:80px 28px 60px;
  text-align:center;
  position:relative;
  overflow:hidden;
  background:linear-gradient(180deg,rgba(124,92,252,0.08) 0%,transparent 100%);
}

.challenge-hero::before{
  content:'';
  position:absolute;
  top:0;
  left:0;
  right:0;
  bottom:0;
  background:radial-gradient(ellipse 80% 50% at 50% 0%,rgba(124,92,252,0.15),transparent);
  pointer-events:none;
}

.hero-badge{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:8px 20px;
  background:rgba(124,92,252,0.1);
  border:1px solid rgba(124,92,252,0.2);
  border-radius:100px;
  font-size:13px;
  color:var(--a2);
  margin-bottom:24px;
  font-weight:500;
}

.hero-badge .pulse{
  width:8px;
  height:8px;
  border-radius:50%;
  background:var(--g);
  box-shadow:0 0 10px var(--g);
  animation:pulse 2s ease-in-out infinite;
}

@keyframes pulse{
  0%,100%{opacity:1;transform:scale(1)}
  50%{opacity:.5;transform:scale(1.2)}
}

.challenge-hero h1{
  font-size:clamp(36px,5vw,56px);
  font-weight:800;
  letter-spacing:-2px;
  margin-bottom:16px;
  background:linear-gradient(135deg,#fff 0%,var(--a2) 100%);
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
}

.challenge-hero .subtitle{
  font-size:18px;
  color:var(--t2);
  max-width:600px;
  margin:0 auto 40px;
  line-height:1.8;
}

/* 统计卡片 */
.stats-grid{
  display:grid;
  grid-template-columns:repeat(4,1fr);
  gap:16px;
  max-width:800px;
  margin:0 auto;
}

.stat-card{
  background:var(--bg2);
  border:1px solid var(--bdr);
  border-radius:16px;
  padding:24px;
  text-align:center;
  transition:all .3s var(--ease);
}

.stat-card:hover{
  border-color:var(--bdr2);
  transform:translateY(-4px);
  box-shadow:0 12px 40px rgba(0,0,0,0.3);
}

.stat-card .number{
  font-size:32px;
  font-weight:800;
  color:var(--t1);
  margin-bottom:8px;
  font-variant-numeric:tabular-nums;
}

.stat-card .label{
  font-size:12px;
  color:var(--t2);
  text-transform:uppercase;
  letter-spacing:1px;
}

/* 筛选和搜索 */
.filter-section{
  max-width:1120px;
  margin:0 auto;
  padding:0 28px 40px;
}

.filter-bar{
  display:flex;
  align-items:center;
  justify-content:space-between;
  flex-wrap:wrap;
  gap:16px;
  background:var(--bg2);
  border:1px solid var(--bdr);
  border-radius:16px;
  padding:20px 24px;
}

.filter-tabs{
  display:flex;
  gap:8px;
}

.filter-tab{
  padding:10px 20px;
  border-radius:10px;
  background:transparent;
  border:1px solid var(--bdr);
  color:var(--t2);
  font-size:14px;
  font-weight:500;
  cursor:pointer;
  transition:all .25s var(--ease);
}

.filter-tab:hover{
  border-color:var(--bdr2);
  color:var(--t1);
}

.filter-tab.active{
  background:var(--a);
  border-color:var(--a);
  color:#fff;
}

.search-box{
  display:flex;
  align-items:center;
  gap:12px;
  background:var(--bg3);
  border:1px solid var(--bdr);
  border-radius:12px;
  padding:10px 16px;
  min-width:280px;
}

.search-box input{
  flex:1;
  background:transparent;
  border:none;
  outline:none;
  color:var(--t1);
  font-size:14px;
}

.search-box input::placeholder{
  color:var(--t3);
}

.search-box svg{
  width:18px;
  height:18px;
  color:var(--t3);
}

/* 项目列表 */
.projects-section{
  max-width:1120px;
  margin:0 auto;
  padding:0 28px 80px;
}

.projects-grid{
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:20px;
}

/* 项目卡片 */
.project-card{
  background:var(--bg2);
  border:1px solid var(--bdr);
  border-radius:20px;
  overflow:hidden;
  transition:all .4s var(--ease);
  position:relative;
}

.project-card::before{
  content:'';
  position:absolute;
  top:0;
  left:0;
  right:0;
  height:3px;
  background:linear-gradient(90deg,var(--a),var(--c));
  opacity:0;
  transition:opacity .3s;
}

.project-card:hover{
  border-color:var(--bdr2);
  transform:translateY(-6px);
  box-shadow:0 20px 60px rgba(0,0,0,0.4),0 0 40px rgba(124,92,252,0.1);
}

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

.card-header{
  padding:24px 24px 0;
  display:flex;
  justify-content:space-between;
  align-items:flex-start;
}

.card-badge{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:6px 12px;
  border-radius:8px;
  font-size:11px;
  font-weight:600;
  text-transform:uppercase;
  letter-spacing:.5px;
}

.badge-active{
  background:rgba(52,211,153,0.1);
  color:var(--g);
  border:1px solid rgba(52,211,153,0.2);
}

.badge-hot{
  background:rgba(244,114,182,0.1);
  color:var(--pk);
  border:1px solid rgba(244,114,182,0.2);
}

.badge-new{
  background:rgba(34,211,238,0.1);
  color:var(--c);
  border:1px solid rgba(34,211,238,0.2);
}

.card-reward{
  font-size:24px;
  font-weight:800;
  color:var(--gd);
}

.card-body{
  padding:20px 24px;
}

.card-title{
  font-size:18px;
  font-weight:700;
  color:var(--t1);
  margin-bottom:12px;
  line-height:1.4;
  display:-webkit-box;
  -webkit-line-clamp:2;
  -webkit-box-orient:vertical;
  overflow:hidden;
}

.card-desc{
  font-size:14px;
  color:var(--t2);
  line-height:1.7;
  margin-bottom:16px;
  display:-webkit-box;
  -webkit-line-clamp:2;
  -webkit-box-orient:vertical;
  overflow:hidden;
}

.card-tags{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  margin-bottom:16px;
}

.tag{
  padding:4px 10px;
  background:var(--bg3);
  border-radius:6px;
  font-size:12px;
  color:var(--t2);
}

.card-meta{
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:12px;
  padding:16px 0;
  border-top:1px solid var(--bdr);
}

.meta-item{
  text-align:center;
}

.meta-item .value{
  font-size:16px;
  font-weight:700;
  color:var(--t1);
  margin-bottom:4px;
}

.meta-item .label{
  font-size:11px;
  color:var(--t3);
  text-transform:uppercase;
  letter-spacing:.5px;
}

.card-footer{
  padding:0 24px 24px;
  display:flex;
  gap:12px;
}

.btn{
  flex:1;
  padding:14px 20px;
  border-radius:12px;
  font-size:14px;
  font-weight:600;
  cursor:pointer;
  transition:all .25s var(--ease);
  border:none;
  display:flex;
  align-items:center;
  justify-content:center;
  gap:8px;
}

.btn-detail{
  background:var(--bg3);
  border:1px solid var(--bdr);
  color:var(--t1);
}

.btn-detail:hover{
  border-color:var(--bdr2);
  background:var(--bg4);
}

.btn-apply{
  background:linear-gradient(135deg,var(--a),#6d4cf7);
  color:#fff;
  box-shadow:0 4px 20px rgba(124,92,252,0.3);
}

.btn-apply:hover{
  transform:translateY(-2px);
  box-shadow:0 8px 30px rgba(124,92,252,0.4);
}

/* 倒计时 */
.countdown{
  display:flex;
  align-items:center;
  gap:6px;
  font-size:12px;
  color:var(--t3);
}

.countdown svg{
  width:14px;
  height:14px;
}

.countdown .urgent{
  color:#ff6b6b;
  font-weight:600;
}

/* 加载动画 */
.loading-overlay{
  position:fixed;
  inset:0;
  background:rgba(6,6,10,0.9);
  display:flex;
  align-items:center;
  justify-content:center;
  z-index:1000;
  opacity:0;
  visibility:hidden;
  transition:all .3s;
}

.loading-overlay.show{
  opacity:1;
  visibility:visible;
}

.loading-spinner{
  width:48px;
  height:48px;
  border:3px solid var(--bdr);
  border-top-color:var(--a);
  border-radius:50%;
  animation:spin 1s linear infinite;
}

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

/* 空状态 */
.empty-state{
  text-align:center;
  padding:80px 20px;
  grid-column:1/-1;
}

.empty-icon{
  font-size:64px;
  margin-bottom:20px;
  opacity:.5;
}

.empty-text{
  font-size:18px;
  color:var(--t2);
  margin-bottom:8px;
}

.empty-desc{
  font-size:14px;
  color:var(--t3);
}

/* 响应式 */
@media(max-width:768px){
  .stats-grid{
    grid-template-columns:repeat(2,1fr);
  }
  .projects-grid{
    grid-template-columns:1fr;
  }
  .filter-bar{
    flex-direction:column;
    align-items:stretch;
  }
  .filter-tabs{
    flex-wrap:wrap;
  }
  .search-box{
    min-width:100%;
  }
}