:root { font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif; color: #1d2939; background: #f5f7fa; }
* { box-sizing: border-box; }
body { margin: 0; }
button, input { font: inherit; }
a { color: inherit; }
.topbar { display: flex; min-height: 64px; padding: 0 32px; align-items: center; justify-content: space-between; color: white; background: #12233f; }
.topbar-subtitle { margin-left: 12px; color: #aebbd0; font-size: 13px; }
.back-link { color: #d8e2f2; text-decoration: none; }
.admin-main { width: min(1180px, calc(100% - 40px)); margin: 34px auto; }
.admin-main.narrow { width: min(780px, calc(100% - 32px)); }
.page-heading { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 22px; }
h1 { margin: 0; font-size: 28px; }
.muted { margin: 7px 0 0; color: #667085; }
.primary-button, .secondary-button, .text-button { border: 0; cursor: pointer; }
.primary-button { padding: 11px 20px; color: white; font-weight: 700; background: #1769e0; border-radius: 9px; }
.secondary-button { padding: 9px 14px; color: #344054; background: white; border: 1px solid #d0d5dd; border-radius: 8px; }
.text-button { color: #d8e2f2; background: transparent; }
.link-button { display: inline-block; text-decoration: none; }
.notice, .panel, .config-card { background: white; border: 1px solid #e4e7ec; border-radius: 14px; box-shadow: 0 4px 16px rgb(16 24 40 / 4%); }
.notice { padding: 18px; color: #667085; }
.config-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 18px; }
.config-card { padding: 20px; }
.config-card h2 { margin: 0 0 8px; font-size: 19px; }
.meta-list { display: grid; gap: 9px; margin: 18px 0; color: #475467; font-size: 14px; }
.short-url { display: block; padding: 10px; overflow: hidden; color: #175cd3; background: #eff8ff; border-radius: 8px; text-overflow: ellipsis; white-space: nowrap; }
.card-actions { display: flex; gap: 9px; margin-top: 16px; }
.status { display: inline-flex; padding: 4px 9px; font-size: 12px; font-weight: 700; border-radius: 999px; }
.status.active { color: #067647; background: #ecfdf3; }
.status.expired, .status.disabled { color: #b42318; background: #fef3f2; }
.panel { padding: 28px; }
.stack-form { display: grid; gap: 20px; }
.stack-form label { display: grid; gap: 7px; color: #344054; font-weight: 650; }
input { width: 100%; padding: 11px 12px; color: #101828; background: white; border: 1px solid #d0d5dd; border-radius: 8px; outline: none; }
input:focus { border-color: #2e90fa; box-shadow: 0 0 0 3px #d1e9ff; }
.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
fieldset { display: grid; gap: 13px; margin: 0; padding: 18px; border: 1px solid #e4e7ec; border-radius: 10px; }
legend { padding: 0 6px; font-weight: 750; }
.expiry-options { display: flex; flex-wrap: wrap; gap: 8px; }
.field-hint { color: #667085; font-size: 13px; font-weight: 400; }
.switch-line { display: flex !important; grid-template-columns: auto 1fr; align-items: center; }
.switch-line input { width: auto; }
.admin-preview { width: min(240px, 100%); padding: 8px; border: 1px solid #e4e7ec; border-radius: 10px; }
.short-link-box { display: grid; grid-template-columns: auto 1fr auto; gap: 12px; align-items: center; padding: 14px; background: #f8fafc; border-radius: 10px; }
.short-link-box code { overflow: hidden; color: #175cd3; text-overflow: ellipsis; }
.form-actions { display: flex; justify-content: flex-end; gap: 10px; }
.form-error { margin: 0; padding: 10px 12px; color: #b42318; background: #fef3f2; border-radius: 8px; }
.form-success { margin: 0; padding: 10px 12px; color: #067647; background: #ecfdf3; border-radius: 8px; }
.copy-tip { position: fixed; top: 18px; right: 18px; z-index: 9999; padding: 10px 14px; color: white; font-weight: 700; background: #067647; border-radius: 8px; box-shadow: 0 12px 28px rgb(16 24 40 / 18%); opacity: 0; transform: translateY(-8px); pointer-events: none; transition: opacity .18s ease, transform .18s ease; }
.copy-tip.error { background: #b42318; }
.copy-tip.visible { opacity: 1; transform: translateY(0); }
.login-body { display: grid; min-height: 100vh; padding: 24px; place-items: center; background: linear-gradient(145deg, #edf4ff, #f8fafc); }
.login-card { width: min(100%, 410px); padding: 38px; background: white; border-radius: 18px; box-shadow: 0 20px 55px rgb(23 50 91 / 12%); }
.login-card h1 { text-align: center; }
.login-card .muted { margin-bottom: 26px; text-align: center; }
.brand-mark { display: grid; width: 54px; height: 54px; margin: 0 auto 18px; place-items: center; color: white; font-size: 24px; font-weight: 900; background: #1769e0; border-radius: 15px; }
@media (max-width: 640px) {
  .topbar { padding: 0 16px; }
  .admin-main { width: min(100% - 24px, 1180px); margin: 22px auto; }
  .page-heading { align-items: flex-start; }
  .field-grid { grid-template-columns: 1fr; }
  .panel { padding: 18px; }
  .short-link-box { grid-template-columns: 1fr; }
}