:root{
  --bg:#f5f6f8; --card:#fff; --line:#e6e8eb; --text:#1f2329;
  --muted:#8a9099; --brand:#3b6ef6; --brand-d:#2f5bd6;
  --ok:#18a058; --err:#d54941; --unread:#fff8e6;
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--text);
  font:14px/1.6 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}

/* 登录页 */
.login-body{display:flex;align-items:center;justify-content:center;min-height:100vh}
.login-card{width:360px;background:var(--card);border:1px solid var(--line);
  border-radius:12px;padding:32px 28px;box-shadow:0 6px 24px rgba(0,0,0,.06)}
.login-card h1{margin:0 0 4px;font-size:20px}
.login-card .sub{margin:0 0 20px;color:var(--muted);font-size:13px}
.login-card label{display:block;margin:12px 0 6px;font-size:13px;color:#5b6169}
.login-card input{width:100%;padding:10px 12px;border:1px solid var(--line);
  border-radius:8px;font-size:14px;outline:none;transition:.15s}
.login-card input:focus{border-color:var(--brand)}
.login-card button{width:100%;margin-top:20px;padding:11px;border:0;border-radius:8px;
  background:var(--brand);color:#fff;font-size:15px;cursor:pointer;transition:.15s}
.login-card button:hover{background:var(--brand-d)}
.login-card .tip{margin:16px 0 0;font-size:12px;color:var(--muted);line-height:1.5}

.alert{padding:10px 12px;border-radius:8px;margin:12px 0;font-size:13px}
.alert-error{background:#fdeceb;color:var(--err);border:1px solid #f8c9c6}
.alert-ok{background:#eaf7ef;color:var(--ok);border:1px solid #bfe5cd}

/* 顶栏 */
.topbar{display:flex;align-items:center;justify-content:space-between;
  height:56px;padding:0 20px;background:var(--card);border-bottom:1px solid var(--line);
  position:sticky;top:0;z-index:10}
.brand{font-size:16px;font-weight:600}
.who{color:var(--muted);font-size:13px;display:flex;align-items:center;gap:10px}
.btn-mini{padding:4px 10px;border:1px solid var(--line);border-radius:6px;
  background:#fff;color:#5b6169;text-decoration:none;font-size:12px;transition:.15s}
.btn-mini:hover{border-color:var(--brand);color:var(--brand)}

.wrap{max-width:900px;margin:16px auto;padding:0 16px}

/* 工具条 */
.toolbar{display:flex;align-items:center;justify-content:space-between;
  padding:12px 14px;background:var(--card);border:1px solid var(--line);border-radius:10px 10px 0 0}
.tabs{display:flex;gap:8px}
.tab{padding:5px 12px;border-radius:6px;color:#5b6169;text-decoration:none;font-size:13px}
.tab:hover{background:#f0f2f5}
.tab.on{background:var(--brand);color:#fff}
.badge{display:inline-block;min-width:18px;padding:0 5px;border-radius:9px;
  background:#fff;color:var(--brand);font-size:11px;line-height:18px;text-align:center}
.meta{color:var(--muted);font-size:12px}

/* 列表 */
.mail-list{list-style:none;margin:0;padding:0;background:var(--card);
  border:1px solid var(--line);border-top:0;border-radius:0 0 10px 10px;overflow:hidden}
.mail-item{border-bottom:1px solid #f0f2f5}
.mail-item:last-child{border-bottom:0}
.mail-item a{display:flex;align-items:center;gap:10px;padding:12px 14px;text-decoration:none;color:inherit}
.mail-item a:hover{background:#f7f9fc}
.mail-item .dot{width:7px;height:7px;border-radius:50%;background:transparent;flex:none}
.mail-item.unread{background:var(--unread)}
.mail-item.unread .dot{background:var(--brand)}
.mail-item.unread .subject{font-weight:600}
.mail-item .from{width:150px;flex:none;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;color:#5b6169}
.mail-item .subject{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.mail-item .size{width:70px;flex:none;text-align:right;color:var(--muted);font-size:12px}
.mail-item .time{width:120px;flex:none;text-align:right;color:var(--muted);font-size:12px;font-variant-numeric:tabular-nums}
.empty{padding:60px 0;text-align:center;color:var(--muted);background:var(--card);
  border:1px solid var(--line);border-top:0;border-radius:0 0 10px 10px}

.pager{display:flex;gap:12px;align-items:center;justify-content:center;padding:14px;color:var(--muted);font-size:13px}
.pager a{color:var(--brand);text-decoration:none}

/* 详情 */
.actions{display:flex;align-items:center;gap:8px;padding:12px 14px;background:var(--card);
  border:1px solid var(--line);border-radius:10px}
.read-state{margin-left:auto;font-size:13px}
.read-state.ok{color:var(--ok)}
.read-state.no{color:#e8912d}

.mail-head{padding:18px 20px;background:var(--card);border:1px solid var(--line);
  border-radius:10px;margin-top:12px}
.mail-head h2{margin:0 0 12px;font-size:18px;line-height:1.5}
.mail-head .line{color:#5b6169;font-size:13px;margin:4px 0;word-break:break-all}
.mail-head .k{display:inline-block;width:56px;color:var(--muted)}

.attach{padding:12px 20px;background:var(--card);border:1px solid var(--line);
  border-top:0;display:flex;flex-wrap:wrap;gap:8px;align-items:center}
.attach-title{width:100%;color:var(--muted);font-size:12px}
.chip{display:inline-block;padding:5px 10px;border:1px solid var(--line);border-radius:6px;
  text-decoration:none;color:#5b6169;font-size:12px}
.chip:hover{border-color:var(--brand);color:var(--brand)}
.chip em{font-style:normal;color:var(--muted);margin-left:4px}

.body-tabs{display:flex;gap:8px;padding:12px 20px 0;background:var(--card);
  border:1px solid var(--line);border-top:0}
.mail-body{background:var(--card);border:1px solid var(--line);border-top:0;
  border-radius:0 0 10px 10px;padding:20px;min-height:200px}
.plain{margin:0;white-space:pre-wrap;word-break:break-word;font:14px/1.75 inherit}
.html-frame{width:100%;height:640px;border:0;display:block}

@media (max-width:640px){
  .mail-item .from{width:96px}
  .mail-item .size{display:none}
  .mail-item .time{width:96px}
}

/* 调试框（?debug=1） */
.debug-box{margin-top:14px;padding:14px 18px;background:#fff;border:1px solid #f5d9a0;
  border-radius:10px;font-size:12px}
.debug-title{color:#a8751a;font-weight:600;margin-bottom:8px}
.debug-box table{width:100%;border-collapse:collapse;border:0;background:transparent}
.debug-box th{width:110px;padding:5px 8px;background:#faf6ec;color:#8a6d3b;font-weight:500;
  border-bottom:1px solid #f0e4c8;text-align:left;vertical-align:top;white-space:nowrap}
.debug-box td{padding:5px 8px;border-bottom:1px solid #f5efe0;word-break:break-all}
.debug-box code{background:#f4f0e6;padding:1px 4px;border-radius:3px}
.debug-box .raw{margin:0;max-height:320px;overflow:auto;background:#fdfbf5;color:#5b5142;
  padding:10px;border-radius:6px;font-size:11px;line-height:1.5;white-space:pre-wrap}