:root {
    --bg: #f5f6fa;
    --card: #ffffff;
    --text: #1f2329;
    --muted: #8a8f99;
    --primary: #2f6bff;
    --border: #e8eaed;
    --shadow: 0 2px 12px rgba(0,0,0,.06);
}
* { box-sizing: border-box; }
body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
}
.topbar {
    background: var(--card);
    box-shadow: var(--shadow); position: sticky; top: 0; z-index: 10;
}
.topbar-inner {
    max-width: 980px; margin: 0 auto; padding: 14px 20px;
    display: flex; align-items: center; justify-content: space-between; gap: 12px;
}
.brand { font-size: 20px; font-weight: 700; color: var(--primary); display: flex; align-items: center; }
.brand-home { color: var(--primary); text-decoration: none; }
.brand-home:hover { opacity: .85; }
.meta { display: flex; align-items: center; gap: 10px; font-size: 13px; color: var(--muted); }
.btn-mini {
    border: 1px solid var(--border); background: #fff; color: var(--text);
    padding: 5px 12px; border-radius: 8px; cursor: pointer; font-size: 13px;
    text-decoration: none; transition: .15s;
}
.btn-mini:hover { border-color: var(--primary); color: var(--primary); }
.container { max-width: 1200px; margin: 0 auto; padding: 20px 20px 40px; }

/* 板块网格：一行三个 */
.board-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
    align-items: stretch;
}
@media (max-width: 980px) { .board-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 640px) { .board-grid { grid-template-columns: 1fr; } }

.board {
    background: var(--card); border-radius: 14px; box-shadow: var(--shadow);
    overflow: hidden; display: flex; flex-direction: column;
    height: 660px;
    animation: fade .2s;
}
.board-head {
    display: flex; align-items: center; justify-content: space-between;
    padding: 14px 18px; border-bottom: 1px solid var(--border); flex: 0 0 auto;
}
.board-head h2 { margin: 0; font-size: 16px; display: flex; align-items: center; }
.p-ico {
    width: 22px; height: 22px; object-fit: cover; display: block;
    border-radius: 6px; background: #f0f2f5; flex: 0 0 auto;
}
.p-name { margin-left: 8px; }
.more-btn {
    font-size: 13px; color: var(--primary); text-decoration: none;
    padding: 4px 8px; border-radius: 8px; transition: .15s; white-space: nowrap;
}
.more-btn:hover { background: rgba(47,107,255,.08); text-decoration: underline; }

@keyframes fade { from { opacity: 0; } to { opacity: 1; } }
.list { list-style: none; margin: 0; padding: 0; }
.board .list { background: var(--card); flex: 1 1 auto; overflow-y: auto; scrollbar-width: none; -ms-overflow-style: none; }
.board .list::-webkit-scrollbar { display: none; }
.board-detail {
    background: var(--card); border-radius: 14px; box-shadow: var(--shadow);
    overflow: hidden; max-width: 760px; margin: 0 auto;
}
.item { display: flex; align-items: center; gap: 12px; padding: 13px 18px; border-bottom: 1px solid var(--border); }
.item:last-child { border-bottom: none; }
.item:hover { background: #fafbff; }
.rank {
    width: 26px; height: 26px; flex: 0 0 26px; border-radius: 8px;
    display: flex; align-items: center; justify-content: center;
    font-weight: 700; font-size: 13px; background: #f0f2f5; color: var(--muted);
}
.rank-1 { background: #ffece8; color: #f5452b; }
.rank-2 { background: #fff3e0; color: #ff8a00; }
.rank-3 { background: #fff8e1; color: #f5b400; }
.title { flex: 1; color: var(--text); text-decoration: none; font-size: 15px; line-height: 1.4; }
.title:hover { color: var(--primary); }
.hot { font-size: 12px; color: var(--muted); flex: 0 0 auto; }
.empty { padding: 30px; text-align: center; color: var(--muted); }
.foot { text-align: center; color: var(--muted); font-size: 12px; padding: 20px; }

/* 登录 */
.login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center; }
.login-box { background: var(--card); padding: 36px; border-radius: 16px; box-shadow: var(--shadow); width: 320px; display: flex; flex-direction: column; gap: 12px; }
.login-box h1 { margin: 0 0 8px; font-size: 20px; text-align: center; color: var(--primary); }
.login-box input { padding: 11px 14px; border: 1px solid var(--border); border-radius: 10px; font-size: 14px; }
.login-box button { padding: 11px; border: none; background: var(--primary); color: #fff; border-radius: 10px; font-size: 15px; cursor: pointer; }
.login-box .back { text-align: center; font-size: 13px; color: var(--muted); text-decoration: none; }

/* 后台 */
.admin .card { background: var(--card); border-radius: 14px; box-shadow: var(--shadow); padding: 20px; margin-bottom: 18px; }
.admin h2 { margin: 0 0 12px; font-size: 17px; }
.hint { color: var(--muted); font-size: 13px; }
.alert { background: #fff0f0; color: #d33; padding: 10px 14px; border-radius: 8px; font-size: 13px; margin: 10px 0; }
.alert-ok { background: #ecf8f0; color: #1a8a4a; }
.ptable { width: 100%; border-collapse: collapse; font-size: 14px; }
.ptable th, .ptable td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--border); }
.ptable th { color: var(--muted); font-weight: 600; }
.on { color: #1a8a4a; } .off { color: var(--muted); }
code { background: #f0f2f5; padding: 2px 6px; border-radius: 6px; font-size: 12px; }
.steps { font-size: 14px; line-height: 1.9; }
.steps b { color: var(--primary); }
.pass-form { display: flex; flex-direction: column; gap: 10px; max-width: 320px; }
.pass-form input { padding: 11px 14px; border: 1px solid var(--border); border-radius: 10px; font-size: 14px; outline: none; }
.pass-form input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(47,107,255,.12); }
.pass-form button { padding: 11px; border: none; background: var(--primary); color: #fff; border-radius: 10px; font-size: 15px; cursor: pointer; }
.pass-form button:hover { opacity: .92; }

/* 搜索框 */
.search-wrap { position: relative; display: inline-flex; align-items: center; }
.search-icon { position: absolute; left: 12px; color: var(--muted); pointer-events: none; }
.search {
    padding: 8px 14px 8px 34px; border: 1px solid var(--border); border-radius: 999px;
    font-size: 13px; width: 190px; outline: none; background: #f5f6fa; color: var(--text);
    transition: .18s; box-shadow: inset 0 1px 2px rgba(0,0,0,.03);
}
.search::placeholder { color: var(--muted); }
.search:focus {
    border-color: var(--primary); background: #fff; width: 240px;
    box-shadow: 0 0 0 3px rgba(47,107,255,.12);
}

/* 板块详情页头部返回 */
.back-link {
    display: inline-flex; align-items: center; justify-content: center;
    width: 30px; height: 30px; margin-right: 8px; border-radius: 8px;
    font-size: 22px; line-height: 1; color: var(--muted); text-decoration: none;
    border: 1px solid var(--border); transition: .15s;
}
.back-link:hover { color: var(--primary); border-color: var(--primary); background: rgba(47,107,255,.06); }

/* 板块详情页 hero 头部 */
.detail-hero {
    display: flex; align-items: center; gap: 14px;
    padding: 20px 22px; border-bottom: 1px solid var(--border);
}
.detail-hero .p-ico { width: 40px; height: 40px; border-radius: 10px; }
.detail-hero-text { display: flex; flex-direction: column; gap: 4px; min-width: 0; }
.detail-hero-text h1 { margin: 0; font-size: 20px; font-weight: 700; }
.detail-sub { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); }
.detail-count { color: var(--primary); font-weight: 600; }
.detail-dot { color: var(--border); }