* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background .3s ease, color .3s ease;
}
a { color: var(--brand); text-decoration: none; }

/* 顶部栏 */
.topbar {
  position: sticky; top: 0; z-index: 30;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px clamp(16px, 4vw, 40px);
  background: color-mix(in srgb, var(--bg-soft) 86%, transparent);
  backdrop-filter: saturate(1.2) blur(10px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 18px; }
.brand .logo { width: 34px; height: 34px; border-radius: 50%; background: var(--grad-brand); display: grid; place-items: center; box-shadow: var(--shadow-sm); }
.brand .logo svg { width: 22px; height: 22px; }
.brand small { color: var(--text-mute); font-weight: 500; font-size: 12px; margin-left: 4px; }
.theme-toggle {
  border: 1px solid var(--line-strong); background: var(--bg-soft); color: var(--text-soft);
  width: 38px; height: 38px; border-radius: 50%; cursor: pointer; font-size: 16px; display: grid; place-items: center;
  transition: transform .2s ease, border-color .2s;
}
.theme-toggle:hover { transform: rotate(-15deg); border-color: var(--brand); }

/* 布局 */
.wrap { max-width: 1080px; margin: 0 auto; padding: clamp(20px, 4vw, 40px) clamp(16px, 4vw, 40px) 60px; }
.hero { text-align: center; margin-bottom: 28px; }
.hero h1 { font-size: clamp(24px, 4vw, 34px); margin: 8px 0 6px; }
.hero p { color: var(--text-soft); margin: 0 auto; max-width: 560px; }
.grid { display: grid; grid-template-columns: 1fr; gap: 24px; }
@media (min-width: 880px) { .grid { grid-template-columns: 1.05fr 0.95fr; align-items: start; } }

/* 卡片 */
.card {
  background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow-sm); padding: clamp(18px, 3vw, 26px);
}
.card h2 { margin: 0 0 4px; font-size: 19px; display: flex; align-items: center; gap: 8px; }
.card .sub { color: var(--text-mute); font-size: 13px; margin: 0 0 18px; }

/* 表单 */
.field { margin-bottom: 16px; }
.field > label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 7px; color: var(--text-soft); }
.field .opt { color: var(--text-mute); font-weight: 400; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  border: 1px solid var(--line-strong); background: var(--bg-elev); color: var(--text-soft);
  padding: 8px 14px; border-radius: 999px; cursor: pointer; font-size: 13px; transition: all .18s;
  user-select: none;
}
.chip:hover { border-color: var(--brand); }
.chip.active { background: var(--grad-brand); color: var(--brand-ink); border-color: transparent; box-shadow: var(--shadow-sm); }
input[type="text"], textarea {
  width: 100%; padding: 12px 14px; border: 1px solid var(--line-strong); border-radius: var(--radius-sm);
  background: var(--bg); color: var(--text); font-size: 14px; font-family: inherit; transition: border-color .2s, box-shadow .2s;
}
input[type="text"]:focus, textarea:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 4px var(--ring); }
textarea { resize: vertical; min-height: 120px; }
.counter { text-align: right; font-size: 12px; color: var(--text-mute); margin-top: 6px; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  border: none; cursor: pointer; font-size: 15px; font-weight: 700; font-family: inherit;
  padding: 13px 22px; border-radius: var(--radius-sm); background: var(--grad-brand); color: var(--brand-ink);
  box-shadow: var(--shadow-sm); transition: transform .15s, filter .2s; width: 100%;
}
.btn:hover { filter: brightness(1.05); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: .6; cursor: not-allowed; }

/* 反馈墙 */
.wall-list { display: flex; flex-direction: column; gap: 12px; max-height: 620px; overflow-y: auto; padding-right: 4px; }
.fb { background: var(--bg-elev); border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px 16px; animation: fade .35s ease; }
.fb .meta { display: flex; align-items: center; gap: 8px; margin-bottom: 6px; }
.tag { font-size: 11px; font-weight: 700; padding: 3px 9px; border-radius: 999px; background: var(--tag-bg); color: var(--brand); }
.tag.Bug反馈 { color: var(--bad); background: color-mix(in srgb, var(--bad) 14%, transparent); }
.tag.投诉 { color: var(--warn); background: color-mix(in srgb, var(--warn) 16%, transparent); }
.tag.其他 { color: var(--text-soft); }
.fb .time { font-size: 12px; color: var(--text-mute); margin-left: auto; }
.fb .content { font-size: 14px; color: var(--text); white-space: pre-wrap; word-break: break-word; }
.wall-empty { text-align: center; color: var(--text-mute); padding: 30px 0; }
.wall-more { margin-top: 14px; text-align: center; }
.wall-more button { width: auto; padding: 9px 18px; font-size: 13px; background: var(--bg-elev); color: var(--text-soft); box-shadow: none; border: 1px solid var(--line-strong); }

/* 骨架屏 */
.skel { background: linear-gradient(90deg, var(--skeleton) 25%, color-mix(in srgb, var(--skeleton) 60%, #fff) 37%, var(--skeleton) 63%); background-size: 400% 100%; animation: shimmer 1.4s infinite; border-radius: 8px; }
@keyframes shimmer { 0% { background-position: 100% 0; } 100% { background-position: -100% 0; } }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

/* Toast */
.toast {
  position: fixed; left: 50%; bottom: 32px; transform: translateX(-50%) translateY(20px);
  background: var(--text); color: var(--bg-soft); padding: 12px 20px; border-radius: 999px;
  font-size: 14px; box-shadow: var(--shadow); opacity: 0; pointer-events: none; transition: all .3s ease; z-index: 60;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.toast.ok { background: var(--ok); }
.toast.err { background: var(--bad); }

footer { text-align: center; color: var(--text-mute); font-size: 12px; padding: 24px 16px 40px; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}