/* ============ 九（9）班 · 暗色极简风格 ============ */
:root{
  --bg:#e9ebef; --card:#f4f5f7; --ink:#1d2129; --sub:#6b7280;
  --line:#dcdfe4; --brand:#2f6bff; --brand-d:#1c4fd6;
  --fun:#c2410c; --event:#2f6bff; --study:#0d9488;
  --danger:#dc2626; --shadow:0 1px 3px rgba(29,33,41,.10);
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%}
body{
  font-family:"PingFang SC","Microsoft YaHei","WenQuanYi Micro Hei",system-ui,-apple-system,sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.7;font-size:15px;
}
a{color:var(--brand);text-decoration:none}
.wrap{max-width:1080px;margin:0 auto;padding:0 18px}

/* 顶部导航 */
.nav{
  position:sticky;top:0;z-index:50;background:#f0f1f4;border-bottom:1px solid var(--line);
}
.nav-in{display:flex;align-items:center;gap:22px;height:52px}
.logo{font-size:18px;font-weight:800;letter-spacing:.5px;color:var(--ink)}
.logo span{color:var(--sub)}
.nav-links{display:flex;gap:18px;flex:1}
.nav-links a{font-size:14px;color:var(--sub);font-weight:600;transition:.2s}
.nav-links a:hover{color:var(--ink)}
.nav-act{margin-left:auto;display:flex;align-items:center;gap:10px}
#who{font-size:13px;color:var(--sub)}
.btn{
  border:1px solid var(--line);border-radius:6px;padding:7px 14px;font-size:13.5px;font-weight:600;
  cursor:pointer;transition:.2s;font-family:inherit;background:#eceef1;color:var(--ink)
}
.btn:hover{border-color:#b9bfc8;background:#e2e5ea}
.btn-brand{background:var(--ink);color:#fff;border-color:var(--ink)}
.btn-brand:hover{background:#000;border-color:#000}
.btn-ghost{background:#f4f5f7}
.btn-danger{background:#fff;color:var(--danger);border-color:#f0c4c4}
.btn-danger:hover{background:var(--danger);color:#fff;border-color:var(--danger)}
.btn-sm{padding:4px 10px;font-size:12.5px;border-radius:5px}

/* 头部横幅 */
.hero{
  background:#25282e;color:#e8eaed;padding:44px 0 38px;
}
.hero h1{font-size:28px;letter-spacing:1px;margin-bottom:8px;font-weight:800}
.hero p{font-size:14px;color:#a8adb5}
.hero .stat{margin-top:22px;display:flex;justify-content:center;gap:40px;flex-wrap:wrap;border-top:1px solid #3a3e45;padding-top:18px}
.hero .stat div{font-size:12.5px;color:#8d929a}
.hero .stat b{display:block;font-size:22px;font-weight:800;color:#fff;margin-top:2px}

/* 板块 */
.section{padding:30px 0}
.sec-head{display:flex;align-items:baseline;gap:10px;margin-bottom:16px;flex-wrap:wrap;border-bottom:1px solid var(--line);padding-bottom:10px}
.sec-head h2{font-size:18px;font-weight:800}
.sec-head .tag{font-size:11.5px;font-weight:700;padding:2px 8px;border-radius:4px;color:#fff;letter-spacing:.5px}
.tag-fun{background:var(--fun)} .tag-event{background:var(--event)} .tag-study{background:var(--study)}
.sec-head .more{margin-left:auto;font-size:13px;color:var(--sub)}
.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:14px}
.card{
  background:var(--card);border:1px solid var(--line);border-radius:8px;padding:16px;
  box-shadow:var(--shadow);transition:.18s;position:relative;
}
.card:hover{border-color:#b9bfc8}
.card h3{font-size:15.5px;margin-bottom:8px;line-height:1.5;font-weight:700}
.card p{font-size:13.5px;color:var(--sub);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.card .meta{margin-top:12px;font-size:12px;color:#8d929a;display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.card .meta .act{margin-left:auto;display:none;gap:8px}
.card:hover .meta .act{display:inline}
.meta a{color:var(--sub);font-size:12px;cursor:pointer}
.meta a:hover{color:var(--danger)}
.empty{padding:26px;text-align:center;color:var(--sub);background:var(--card);border:1px dashed var(--line);border-radius:8px}
.err{padding:14px;background:#fdf0f0;color:var(--danger);border:1px solid #f0c4c4;border-radius:6px;font-size:13.5px}
.spinner{width:20px;height:20px;border:2px solid var(--line);border-top-color:var(--brand);border-radius:50%;animation:spin 1s linear infinite;margin:0 auto}
@keyframes spin{to{transform:rotate(360deg)}}

/* 评论区 */
.comments{margin-top:12px;border-top:1px dashed var(--line);padding-top:12px;display:none}
.comments.show{display:block}
.comments .ct{font-size:12px;color:var(--sub);margin-bottom:10px;font-weight:700}
.comments .item{font-size:13px;padding:8px 0;border-bottom:1px solid #e6e8ec}
.comments .item:last-child{border-bottom:0}
.comments .item .who{color:var(--ink);font-weight:700;margin-right:6px}
.comments .item .when{color:#a8adb5;font-size:11.5px;margin-left:6px}
.comments .none{font-size:12.5px;color:#a8adb5;padding:6px 0}
.comments .cform{display:flex;gap:8px;margin-top:10px}
.comments .cform input{flex:1;padding:7px 10px;border:1px solid var(--line);border-radius:6px;font-size:13px;font-family:inherit}
.comments .cform input:focus{outline:none;border-color:var(--ink)}
.comments .cform button{padding:7px 14px;border-radius:6px;font-size:13px;font-weight:700;cursor:pointer;border:1px solid var(--ink);background:var(--ink);color:#fff;font-family:inherit}
.comments .cform button:hover{background:#000}
/* 点赞 / 举报 */
.react{display:flex;gap:14px;margin-top:10px;font-size:12px;color:var(--sub);align-items:center}
.react button{background:none;border:0;cursor:pointer;font-size:12px;color:var(--sub);font-family:inherit;padding:0;display:flex;align-items:center;gap:4px}
.react button:hover{color:var(--ink)}
.react button.on{color:var(--brand);font-weight:700}
.react .rep{margin-left:auto}
.react .rep:hover{color:var(--danger)}

/* 弹窗 */
.mask{
  position:fixed;inset:0;background:rgba(20,22,26,.55);z-index:100;
  display:none;place-items:center;padding:16px;
}
.mask.on{display:grid}
.modal{background:#f4f5f7;border:1px solid var(--line);border-radius:8px;width:100%;max-width:500px;padding:22px;box-shadow:0 16px 48px rgba(0,0,0,.35);max-height:92vh;overflow:auto}
.modal h3{font-size:17px;margin-bottom:16px;font-weight:800}
.field{margin-bottom:13px}
.field label{display:block;font-size:13px;font-weight:700;margin-bottom:6px;color:var(--sub)}
.field input,.field textarea,.field select{
  width:100%;padding:9px 11px;border:1px solid var(--line);border-radius:6px;font-size:14px;
  font-family:inherit;transition:.2s;background:#fff;color:var(--ink)
}
.field input:focus,.field textarea:focus,.field select:focus{outline:none;border-color:var(--ink)}
.field textarea{min-height:110px;resize:vertical;line-height:1.6}
.modal-act{display:flex;gap:10px;justify-content:flex-end;margin-top:6px}
.modal-act .btn{flex:1}
.toast{
  position:fixed;left:50%;bottom:28px;transform:translateX(-50%) translateY(20px);
  background:#25282e;color:#e8eaed;padding:10px 20px;border-radius:6px;font-size:13.5px;
  opacity:0;pointer-events:none;transition:.25s;z-index:200;box-shadow:0 6px 20px rgba(0,0,0,.3)
}
.toast.on{opacity:1;transform:translateX(-50%) translateY(0)}
.toast.err{background:#8c1d1d;color:#fff}

/* 页脚 */
.foot{text-align:center;padding:24px 0;color:#8d929a;font-size:12.5px;border-top:1px solid var(--line);margin-top:20px}

@media (max-width:640px){
  .hero h1{font-size:23px}
  .nav-links{display:none}
  .sec-head .more{margin-left:0;width:100%}
}