/* 校园AI大赛 · 社区 —— 与官网 B 版同视觉家族 */
:root {
  --bg: #f6f5fb;
  --ink: #1e1b2e;
  --ink-2: #6b6784;
  --grad-main: linear-gradient(135deg, #6d5ae0 0%, #a855f7 55%, #ec4899 100%);
  --card: #ffffff;
  --line: #e9e6f5;
  --violet: #6d5ae0;
  --violet-soft: #efeaff;
  --creative: #f97316;
  --creative-soft: #fff1e6;
  --practice: #0ea5e9;
  --practice-soft: #e6f6fe;
  --chat: #10b981;
  --chat-soft: #e6faf2;
  --radius: 16px;
  --shadow: 0 8px 28px rgba(80, 60, 160, .10);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  background: var(--bg); color: var(--ink); min-height: 100vh; position: relative;
  overflow-x: hidden;
}
.blob { position: fixed; border-radius: 50%; filter: blur(90px); opacity: .35; z-index: -1; pointer-events: none; }
.blob-1 { width: 480px; height: 480px; background: #c4b5fd; top: -160px; right: -120px; }
.blob-2 { width: 420px; height: 420px; background: #fbcfe8; bottom: -160px; left: -120px; }
a { color: inherit; text-decoration: none; }
button { font-family: inherit; }

/* 导航 */
.nav {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 20px; margin: 12px auto; max-width: 880px;
  border-radius: 18px;
}
.glass { background: rgba(255,255,255,.72); backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px); border: 1px solid rgba(255,255,255,.6); box-shadow: var(--shadow); }
.brand { display: flex; align-items: center; gap: 10px; }
.logo { width: 34px; height: 34px; border-radius: 9px; object-fit: cover; }
.brand-text { font-size: 15px; color: var(--ink-2); }
.brand-text b { color: var(--ink); }
.nav-links { display: flex; align-items: center; gap: 6px; }
.nav-link { padding: 8px 14px; border-radius: 12px; font-size: 14px; color: var(--ink-2); font-weight: 500; }
.nav-link:hover { background: var(--violet-soft); color: var(--violet); }
.nav-user { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--ink-2); }
.nav-user .who { color: var(--violet); font-weight: 600; }
.mini-btn { border: none; background: none; color: var(--ink-2); font-size: 13px; cursor: pointer; padding: 6px 8px; border-radius: 8px; }
.mini-btn:hover { background: var(--violet-soft); color: var(--violet); }

/* 布局 */
.container { max-width: 880px; margin: 0 auto; padding: 8px 16px 60px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); }

/* 分区标签栏 */
.feed-head { display: flex; align-items: center; justify-content: space-between; gap: 10px; margin: 6px 2px 14px; flex-wrap: wrap; }
.tabs { display: flex; gap: 8px; flex-wrap: wrap; }
.tab { padding: 8px 16px; border-radius: 999px; border: 1px solid var(--line); background: #fff; font-size: 14px; color: var(--ink-2); cursor: pointer; font-weight: 500; }
.tab.active { background: var(--grad-main); color: #fff; border-color: transparent; box-shadow: 0 4px 14px rgba(140,90,230,.35); }
.sort-toggle { display: flex; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; background: #fff; }
.sort-toggle button { border: none; background: none; padding: 8px 14px; font-size: 13px; color: var(--ink-2); cursor: pointer; }
.sort-toggle button.active { background: var(--violet-soft); color: var(--violet); font-weight: 600; }

/* 帖子卡 */
.post-card { display: flex; gap: 14px; padding: 16px; margin-bottom: 14px; cursor: pointer; transition: transform .15s ease, box-shadow .15s ease; }
.post-card:hover { transform: translateY(-2px); box-shadow: 0 12px 32px rgba(80,60,160,.16); }
.post-main { flex: 1; min-width: 0; }
.post-top { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; flex-wrap: wrap; }
.badge { font-size: 12px; padding: 3px 10px; border-radius: 999px; font-weight: 600; }
.badge.creative { color: var(--creative); background: var(--creative-soft); }
.badge.practice { color: var(--practice); background: var(--practice-soft); }
.badge.chat { color: var(--chat); background: var(--chat-soft); }
.badge.pinned { color: var(--violet); background: var(--violet-soft); }
.post-title { font-size: 17px; font-weight: 700; margin-bottom: 6px; }
.post-excerpt { font-size: 14px; color: var(--ink-2); line-height: 1.6; overflow: hidden; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; }
.post-meta { margin-top: 10px; font-size: 12.5px; color: #9a96b3; display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.post-meta .team { color: var(--violet); font-weight: 600; }
.post-thumb { width: 116px; height: 96px; border-radius: 12px; object-fit: cover; flex-shrink: 0; border: 1px solid var(--line); }

/* 详情 */
.detail { padding: 24px; margin-bottom: 16px; }
.detail h1 { font-size: 22px; line-height: 1.4; margin: 8px 0 12px; }
.detail .content { font-size: 15px; line-height: 1.9; color: #3c3854; white-space: pre-wrap; word-break: break-word; }
.img-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 10px; margin-top: 16px; }
.img-grid img { width: 100%; border-radius: 12px; border: 1px solid var(--line); cursor: zoom-in; }
.back { color: var(--ink-2); font-size: 14px; }
.back:hover { color: var(--violet); }

/* 评论 */
.comments { padding: 20px 24px; }
.comments h3 { font-size: 15px; margin-bottom: 14px; color: var(--ink-2); }
.comment { padding: 12px 0; border-bottom: 1px dashed var(--line); font-size: 14px; }
.comment:last-child { border-bottom: none; }
.comment .who { font-weight: 600; color: var(--violet); margin-right: 8px; }
.comment .when { color: #9a96b3; font-size: 12px; margin-left: 8px; }
.comment .text { margin-top: 5px; line-height: 1.7; color: #3c3854; white-space: pre-wrap; word-break: break-word; }
.comment-box { display: flex; gap: 10px; margin-top: 16px; }
.comment-box textarea { flex: 1; resize: vertical; min-height: 44px; max-height: 140px; border: 1px solid var(--line); border-radius: 12px; padding: 10px 14px; font-size: 14px; font-family: inherit; outline: none; }
.comment-box textarea:focus { border-color: var(--violet); }

/* 表单 */
.panel { padding: 28px; max-width: 560px; margin: 20px auto; }
.panel h2 { font-size: 20px; margin-bottom: 4px; }
.panel .sub { font-size: 13.5px; color: var(--ink-2); margin-bottom: 20px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 13.5px; font-weight: 600; margin-bottom: 7px; color: #494565; }
.field input[type=text], .field input[type=password], .field textarea {
  width: 100%; border: 1px solid var(--line); border-radius: 12px; padding: 11px 14px;
  font-size: 14px; font-family: inherit; outline: none; background: #fbfaff; transition: border-color .15s;
}
.field input:focus, .field textarea:focus { border-color: var(--violet); background: #fff; }
.field textarea { resize: vertical; min-height: 130px; line-height: 1.7; }
.field .hint { font-size: 12px; color: #9a96b3; margin-top: 5px; }
.track-pick { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.track-pick label { display: block; text-align: center; padding: 10px 4px; border: 1.5px solid var(--line); border-radius: 12px; font-size: 13.5px; cursor: pointer; font-weight: 500; color: var(--ink-2); }
.track-pick input { display: none; }
.track-pick label.on-creative { color: var(--creative); border-color: var(--creative); background: var(--creative-soft); font-weight: 700; }
.track-pick label.on-practice { color: var(--practice); border-color: var(--practice); background: var(--practice-soft); font-weight: 700; }
.track-pick label.on-chat { color: var(--chat); border-color: var(--chat); background: var(--chat-soft); font-weight: 700; }

.btn-main {
  display: inline-block; width: 100%; border: none; cursor: pointer;
  background: var(--grad-main); color: #fff; font-size: 15px; font-weight: 700;
  padding: 13px; border-radius: 13px; box-shadow: 0 6px 18px rgba(140,90,230,.35);
  transition: transform .12s;
}
.btn-main:hover { transform: translateY(-1px); }
.btn-main:disabled { opacity: .55; cursor: not-allowed; }
.btn-ghost { display: inline-block; border: 1px solid var(--line); background: #fff; color: var(--ink-2); font-size: 14px; font-weight: 500; padding: 11px 18px; border-radius: 12px; cursor: pointer; }
.btn-ghost:hover { color: var(--violet); border-color: var(--violet); }
.form-err { color: #e11d48; font-size: 13.5px; margin: 8px 0; min-height: 18px; }

/* 图片上传 */
.img-pick { display: flex; gap: 10px; flex-wrap: wrap; }
.img-pick .add {
  width: 84px; height: 84px; border: 1.5px dashed #c9c3e6; border-radius: 12px; display: flex;
  align-items: center; justify-content: center; font-size: 26px; color: #a49ecf; cursor: pointer; background: #fbfaff;
}
.img-pick .add:hover { border-color: var(--violet); color: var(--violet); }
.img-pick .thumb { position: relative; width: 84px; height: 84px; }
.img-pick .thumb img { width: 100%; height: 100%; object-fit: cover; border-radius: 12px; border: 1px solid var(--line); }
.img-pick .thumb .rm { position: absolute; top: -7px; right: -7px; width: 22px; height: 22px; border-radius: 50%; background: #1e1b2e; color: #fff; border: none; font-size: 13px; cursor: pointer; line-height: 1; }

/* 登录切换 */
.login-tabs { display: flex; gap: 8px; margin-bottom: 20px; }
.login-tabs button { flex: 1; padding: 10px; border-radius: 11px; border: 1px solid var(--line); background: #fff; font-size: 14px; color: var(--ink-2); cursor: pointer; font-weight: 500; }
.login-tabs button.active { background: var(--violet-soft); color: var(--violet); border-color: transparent; font-weight: 700; }

/* 管理操作条 */
.admin-bar { display: flex; gap: 8px; margin-top: 10px; flex-wrap: wrap; }
.admin-bar button { border: 1px solid var(--line); background: #fff; border-radius: 9px; padding: 6px 12px; font-size: 12.5px; color: var(--ink-2); cursor: pointer; }
.admin-bar button:hover { color: var(--violet); border-color: var(--violet); }
.admin-bar button.danger:hover { color: #e11d48; border-color: #e11d48; }
.admin-tools { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 16px; }

.empty { text-align: center; padding: 60px 20px; color: #9a96b3; font-size: 14.5px; }
.empty .big { font-size: 40px; margin-bottom: 10px; }
.load-more { display: block; margin: 6px auto 0; }

.toast { position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%) translateY(80px); background: #1e1b2e; color: #fff; font-size: 14px; padding: 11px 20px; border-radius: 12px; opacity: 0; transition: all .25s ease; z-index: 99; max-width: 86vw; }
.toast.show { transform: translateX(-50%) translateY(0); opacity: 1; }

.footer { text-align: center; padding: 26px 16px 34px; font-size: 12.5px; color: #a8a4bf; }
.footer a { color: var(--violet); }

.img-mask { position: fixed; inset: 0; background: rgba(15,12,30,.86); z-index: 90; display: flex; align-items: center; justify-content: center; cursor: zoom-out; }
.img-mask img { max-width: 94vw; max-height: 92vh; border-radius: 10px; }

@media (max-width: 560px) {
  .nav { margin: 8px 10px; padding: 9px 12px; }
  .brand-text { font-size: 13.5px; }
  .nav-link { padding: 7px 10px; font-size: 13px; }
  .post-thumb { display: none; }
  .detail { padding: 18px; }
  .track-pick { grid-template-columns: 1fr 1fr 1fr; }
  .track-pick label { font-size: 12px; padding: 9px 2px; }
}