/* 校园墙：实名 = 白底，匿名 = 黑底。左上角开关切换；切换时只有颜色渐变，不堆别的特效 */
:root{color-scheme:light;--bg:#f3f5f9;--card:#fff;--ink:#0d1b33;--mute:#6b7890;--line:#e4e9f1;--soft:#eef2f8;
  --accent:#1f5fd1;--accent-ink:#fff;--danger:#b42318;--ok:#1d8a4e;--ease:cubic-bezier(.16,1,.3,1);
  font-family:system-ui,-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg)}
html[data-mode=anon]{color-scheme:dark;--bg:#07080c;--card:#12151c;--ink:#e8ecf5;--mute:#8b94a8;--line:#222735;--soft:#1a1e29;
  --accent:#8fa6ff;--accent-ink:#0a0d18;--danger:#ff8a80;--ok:#6fdc9c}
[hidden]{display:none!important}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html{background:var(--bg)}
body{margin:0;min-height:100vh;min-height:100svh;background:var(--bg);color:var(--ink);transition:background-color .35s,color .35s}
a{color:var(--accent)}
button{font:inherit;color:inherit}

/* 顶栏 */
.top{position:sticky;top:0;z-index:5;display:flex;align-items:center;justify-content:space-between;gap:10px;max-width:640px;margin:auto;
  padding:calc(env(safe-area-inset-top,0px) + 12px) 16px 12px;background:var(--bg);transition:background-color .35s}
.title{font-size:17px;font-weight:800;letter-spacing:.04em;color:var(--ink);text-decoration:none}
.right{display:flex;align-items:center;gap:8px}
.icon-btn{width:32px;height:32px;border-radius:50%;border:1.5px solid var(--line);background:none;color:var(--mute);font-weight:700;cursor:pointer}
.chip{border:0;background:var(--soft);padding:7px 12px;border-radius:99px;font-size:13px;font-weight:650;cursor:pointer;max-width:130px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}

/* 身份开关：像深浅色切换，一眼看出当前是哪个身份 */
.mode{position:relative;display:grid;grid-template-columns:1fr 1fr;width:112px;padding:3px;border:0;border-radius:99px;background:var(--soft);cursor:pointer}
.mode b{position:relative;z-index:1;font-size:13px;font-weight:700;padding:6px 0;text-align:center;color:var(--mute);transition:color .25s}
.mode .thumb{position:absolute;top:3px;bottom:3px;left:3px;width:calc(50% - 3px);border-radius:99px;background:var(--card);box-shadow:0 1px 6px rgba(0,0,0,.18);transition:transform .35s var(--ease)}
html[data-mode=real] .mode b:first-of-type,html[data-mode=anon] .mode b:last-of-type{color:var(--ink)}
html[data-mode=anon] .mode .thumb{transform:translateX(100%);box-shadow:0 0 14px rgba(143,166,255,.35)}

.wrap{max-width:640px;margin:0 auto;padding:4px 16px calc(env(safe-area-inset-bottom,0px) + 96px)}
.loading,.empty{text-align:center;color:var(--mute);padding:40px 0}
.banner{max-width:640px;margin:0 auto 6px;padding:0 16px}
.banner div{background:var(--soft);border-radius:14px;padding:11px 14px;font-size:13px;line-height:1.6}

/* 筛选 */
.filters{display:flex;gap:8px;align-items:center;overflow-x:auto;padding:2px 0 12px;scrollbar-width:none}
.filters::-webkit-scrollbar{display:none}
.filters button,.filters select{flex:none;border:0;background:var(--soft);color:var(--mute);padding:7px 14px;border-radius:99px;font-size:13px;font-weight:650;cursor:pointer;transition:background-color .2s,color .2s}
.filters button[aria-pressed=true]{background:var(--accent);color:var(--accent-ink)}
.filters select{appearance:none;-webkit-appearance:none;padding-right:14px}

/* 帖子卡片 */
.post{background:var(--card);border-radius:20px;padding:16px;margin-bottom:12px;box-shadow:0 0 0 1px var(--line);transition:background-color .35s,box-shadow .35s}
html[data-mode=anon] .post{box-shadow:0 0 0 1px var(--line),0 8px 30px -18px rgba(143,166,255,.25)}
.meta{display:flex;align-items:center;gap:10px;margin-bottom:10px}
.avatar{width:36px;height:36px;border-radius:12px;display:grid;place-items:center;font-weight:800;font-size:15px;flex:none;background:linear-gradient(135deg,#1f5fd1,#5aa0ef);color:#fff}
.avatar.anon{background:linear-gradient(135deg,#2b3350,#566296);color:#dfe6ff}
.who{min-width:0;flex:1}
.who b{display:block;font-size:14px;word-break:break-all}
.who small{color:var(--mute);font-size:12px}
.tag{display:inline-block;font-size:11px;font-weight:700;padding:1px 7px;border-radius:99px;background:var(--soft);color:var(--mute);margin-left:6px;vertical-align:1px}
.tag.op{background:var(--accent);color:var(--accent-ink)}
.content{white-space:pre-wrap;word-break:break-word;line-height:1.7;font-size:15px;margin:0 0 10px}
.content.click{cursor:pointer}
.folded{width:100%;border:1.5px dashed var(--line);background:none;border-radius:14px;color:var(--mute);padding:14px;cursor:pointer;font-size:13px}
.imgs{display:grid;gap:6px;margin:0 0 10px;grid-template-columns:repeat(2,1fr)}
.imgs.one{grid-template-columns:1fr}
.imgs img{width:100%;aspect-ratio:1/1;object-fit:cover;border-radius:12px;background:var(--soft);cursor:zoom-in}
.imgs.one img{aspect-ratio:auto;max-height:420px}
.acts{display:flex;align-items:center;gap:4px;margin:0 -8px -6px}
.acts button{border:0;background:none;color:var(--mute);padding:8px 10px;border-radius:10px;font-size:13px;font-weight:650;cursor:pointer}
.acts button.on{color:var(--accent)}
.acts .sp{flex:1}

/* 投票 */
.poll{border-radius:14px;background:var(--soft);padding:12px;margin:0 0 10px}
.poll h4{margin:0 0 8px;font-size:12px;color:var(--mute);font-weight:700}
.opt{position:relative;display:flex;align-items:center;gap:8px;width:100%;border:1.5px solid var(--line);background:var(--card);border-radius:12px;padding:10px 12px;margin-bottom:8px;font-size:14px;text-align:left;cursor:pointer;overflow:hidden}
.opt[aria-pressed=true]{border-color:var(--accent)}
.opt .bar{position:absolute;inset:0 auto 0 0;width:var(--w,0%);background:var(--accent);opacity:.16;transition:width .5s var(--ease)}
.opt span{position:relative;flex:1;word-break:break-all}
.opt em{position:relative;font-style:normal;font-size:12px;color:var(--mute);font-weight:700}
.opt.mine{border-color:var(--accent)}
.voters{font-size:12px;color:var(--mute);margin:-4px 0 8px;line-height:1.6}

/* 按钮 */
.btn{display:block;width:100%;border:0;font-size:16px;font-weight:700;padding:13px;border-radius:14px;cursor:pointer;color:var(--accent-ink);background:var(--accent);transition:transform .15s var(--ease),opacity .15s}
.btn:active{transform:scale(.97)}.btn:disabled{opacity:.5;cursor:default}
.btn.ghost{background:var(--soft);color:var(--ink)}.btn.danger{background:none;color:var(--danger);border:1.5px solid var(--danger)}
.btn.sm{display:inline-block;width:auto;font-size:13px;padding:7px 14px;border-radius:99px}
.more{margin:8px 0}
.fab{position:fixed;right:max(20px,calc(50% - 300px));bottom:calc(env(safe-area-inset-bottom,0px) + 22px);width:56px;height:56px;border:0;border-radius:50%;background:var(--accent);color:var(--accent-ink);font-size:28px;line-height:1;cursor:pointer;box-shadow:0 10px 26px -8px rgba(0,0,0,.5);transition:transform .2s var(--ease)}
.fab:active{transform:scale(.92)}
html[data-mode=anon] .fab{box-shadow:0 0 26px rgba(143,166,255,.4)}

/* 弹层 */
.modal{position:fixed;inset:0;z-index:20;display:flex;align-items:flex-end;justify-content:center;background:rgba(5,8,16,.55);animation:fade .2s}
.sheet{width:100%;max-width:640px;max-height:92svh;overflow:auto;background:var(--card);color:var(--ink);border-radius:24px 24px 0 0;padding:20px 18px calc(env(safe-area-inset-bottom,0px) + 20px);animation:up .35s var(--ease)}
.sheet h3{margin:0 0 4px;font-size:18px}.sheet .sub{margin:0 0 14px;color:var(--mute);font-size:13px;line-height:1.6}
@keyframes up{from{transform:translateY(30px);opacity:0}}@keyframes fade{from{opacity:0}}
textarea,input[type=text],input[type=number],select.field{width:100%;font:inherit;font-size:16px;color:var(--ink);background:var(--soft);border:1.5px solid transparent;border-radius:12px;padding:12px 14px;outline:none;transition:border-color .15s}
textarea{min-height:120px;resize:vertical;line-height:1.6}
textarea:focus,input:focus{border-color:var(--accent)}
.row{display:flex;gap:10px;align-items:center;margin:10px 0}
.row label{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--mute)}
.count{margin-left:auto;font-size:12px;color:var(--mute)}
.thumbs{display:flex;gap:8px;flex-wrap:wrap;margin:10px 0}
.thumbs div{position:relative;width:72px;height:72px}
.thumbs img{width:100%;height:100%;object-fit:cover;border-radius:12px}
.thumbs button{position:absolute;top:-6px;right:-6px;width:22px;height:22px;border-radius:50%;border:0;background:#000a;color:#fff;cursor:pointer;line-height:1}
.pick{border:1.5px dashed var(--line);background:none;border-radius:12px;width:72px;height:72px;font-size:24px;color:var(--mute);cursor:pointer}
.as{font-size:13px;color:var(--mute);margin:0 0 10px}.as b{color:var(--accent)}
.err{color:var(--danger);font-size:13px;margin:8px 0 0;min-height:1em}
.dots{display:flex;gap:6px;justify-content:center;margin:12px 0}
.dots i{width:7px;height:7px;border-radius:50%;background:var(--line)}.dots i.on{background:var(--accent)}
.tut{text-align:center;padding:10px 0}.tut .big{font-size:44px;line-height:1.2;margin-bottom:8px}.tut h3{font-size:20px}.tut p{color:var(--mute);line-height:1.7;margin:8px 0 0;font-size:14px}
.menu button,.menu a{display:block;width:100%;text-align:left;border:0;background:none;padding:14px 4px;border-bottom:1px solid var(--line);font-size:15px;cursor:pointer;color:var(--ink);text-decoration:none}

/* 详情页与评论 */
.back{border:0;background:none;color:var(--mute);font-size:14px;font-weight:650;cursor:pointer;padding:6px 0 10px}
.comments{margin-top:6px}
.cm{padding:12px 0;border-top:1px solid var(--line)}
.cm.reply{margin-left:22px}
.cm p{margin:4px 0 6px;white-space:pre-wrap;word-break:break-word;line-height:1.6;font-size:14px}
.cm small{color:var(--mute);font-size:12px}
.cm .link{border:0;background:none;color:var(--mute);font-size:12px;font-weight:650;cursor:pointer;padding:2px 8px 2px 0}
.cbar{position:sticky;bottom:0;background:var(--bg);padding:10px 0 calc(env(safe-area-inset-bottom,0px) + 10px);transition:background-color .35s}
.cbar .replying{font-size:12px;color:var(--mute);margin:0 0 6px}
.cbar .line{display:flex;gap:8px}
.cbar input{flex:1}
.cbar .btn{width:auto;padding:0 18px}

/* 后台 */
.q{background:var(--card);border-radius:16px;padding:14px;margin-bottom:10px;box-shadow:0 0 0 1px var(--line)}
.q .t{font-size:12px;color:var(--mute);margin:0 0 6px}
.q p{margin:0 0 10px;white-space:pre-wrap;word-break:break-word;font-size:14px;line-height:1.6}
.q .btns{display:flex;gap:8px;flex-wrap:wrap}

.toast{position:fixed;left:50%;bottom:calc(env(safe-area-inset-bottom,0px) + 90px);transform:translateX(-50%);z-index:40;background:#111c;color:#fff;backdrop-filter:blur(8px);padding:10px 16px;border-radius:99px;font-size:14px;max-width:86vw;text-align:center}
.lightbox{position:fixed;inset:0;z-index:30;background:#000e;display:grid;place-items:center;padding:16px}
.lightbox img{max-width:100%;max-height:100%;border-radius:8px}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}