:root {
  color-scheme: light dark;
  --page: #f4f6fa;
  --surface: #fbfcfe;
  --surface-raised: #f7f9fc;
  --surface-strong: #e9eef7;
  --text: #182033;
  --text-soft: #5c667a;
  --text-faint: #768197;
  --border: #dce2eb;
  --border-strong: #c8d1df;
  --accent: #2f68d8;
  --accent-strong: #2456b8;
  --accent-soft: #e5edfc;
  --success: #237a57;
  --success-soft: #e1f3eb;
  --warning: #9a6419;
  --warning-soft: #f8edd9;
  --danger: #b4444d;
  --danger-soft: #f8e7e9;
  --shadow: 0 18px 48px rgba(40, 57, 88, 0.1);
  --radius: 8px;
  --topbar-height: 64px;
}

* { box-sizing: border-box; }

html { min-width: 320px; background: var(--page); }

body {
  margin: 0;
  min-height: 100dvh;
  background: var(--page);
  color: var(--text);
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  font-size: 15px;
  line-height: 1.55;
  letter-spacing: 0;
}

button, input, select { font: inherit; letter-spacing: 0; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: inherit; }

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 20;
  transform: translateY(-150%);
  padding: 8px 12px;
  border-radius: 4px;
  background: var(--text);
  color: var(--surface);
}

.skip-link:focus { transform: translateY(0); }

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  height: var(--topbar-height);
  border-bottom: 1px solid var(--border);
  background: var(--page);
}

.topbar__inner {
  width: min(1180px, calc(100% - 40px));
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; white-space: nowrap; }
.brand__mark {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  border-radius: 7px;
  background: var(--accent);
  color: #f8faff;
  font-size: 15px;
  font-weight: 800;
}
.brand__name { font-weight: 750; }
.brand__divider { width: 1px; height: 16px; background: var(--border-strong); }
.brand__product { color: var(--text-soft); font-size: 14px; }

.page-shell { width: min(1180px, calc(100% - 40px)); margin: 0 auto; padding: 42px 0 72px; outline: none; }
.eyebrow { display: block; margin-bottom: 8px; color: var(--accent); font-size: 13px; font-weight: 700; }

h1, h2, p { margin-top: 0; }
h1 { max-width: 760px; margin-bottom: 12px; font-size: clamp(28px, 4vw, 42px); line-height: 1.18; font-weight: 760; }
h2 { margin-bottom: 6px; font-size: 20px; line-height: 1.3; }

.button, .icon-button {
  border: 0;
  cursor: pointer;
  transition: background-color 160ms ease, border-color 160ms ease, color 160ms ease, transform 120ms ease;
}
.button:active, .icon-button:active { transform: translateY(1px); }
.button:disabled, .icon-button:disabled { cursor: not-allowed; opacity: 0.55; }
.button:focus-visible, .icon-button:focus-visible, .segmented button:focus-visible, input:focus-visible, select:focus-visible, summary:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--accent) 30%, transparent);
  outline-offset: 2px;
}
.button {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 16px;
  border-radius: 7px;
  text-decoration: none;
  font-weight: 700;
  white-space: nowrap;
}
.button i { font-size: 18px; }
.button--primary { background: var(--accent); color: #f8faff; }
.button--primary:hover { background: var(--accent-strong); }
.button--quiet { border: 1px solid var(--border); background: var(--surface); color: var(--text); }
.button--quiet:hover { border-color: var(--border-strong); background: var(--surface-raised); }
.button--small { min-height: 36px; padding: 0 12px; font-size: 14px; }

.icon-button {
  width: 38px;
  height: 38px;
  flex: 0 0 38px;
  display: grid;
  place-items: center;
  border-radius: 7px;
  background: transparent;
  color: var(--text-soft);
  font-size: 20px;
}
.icon-button:hover { background: var(--surface-strong); color: var(--text); }
.icon-button--bordered { border: 1px solid var(--border); background: var(--surface); }

.account { display: flex; align-items: center; gap: 9px; }
.account__avatar { width: 32px; height: 32px; border-radius: 50%; object-fit: cover; background: var(--accent-soft); }
.account__avatar--fallback { display: grid; place-items: center; color: var(--accent); font-weight: 800; }
.account__name { max-width: 180px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 14px; font-weight: 650; }

.login-view {
  min-height: calc(100dvh - var(--topbar-height) - 114px);
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.65fr);
  align-items: center;
  gap: clamp(42px, 8vw, 110px);
}
.login-copy > p { max-width: 610px; color: var(--text-soft); font-size: 17px; }
.login-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 26px; }
.privacy-note { display: flex; align-items: center; gap: 7px; margin: 18px 0 0; font-size: 13px !important; color: var(--text-faint) !important; }
.privacy-note i { color: var(--success); font-size: 17px; }
.reward-preview {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.reward-preview__top { min-height: 54px; display: flex; align-items: center; justify-content: space-between; padding: 0 22px; border-bottom: 1px solid var(--border); font-weight: 700; }
.reward-preview__top i { color: var(--accent); font-size: 23px; }
.reward-preview dl { margin: 0; padding: 8px 22px; }
.reward-preview dl div { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 19px 0; }
.reward-preview dl div + div { border-top: 1px solid var(--border); }
.reward-preview dt { color: var(--text-soft); }
.reward-preview dd { margin: 0; color: var(--accent); font-size: 26px; font-weight: 780; }
.reward-preview dd small { color: var(--text-soft); font-size: 12px; font-weight: 650; }
.reward-preview .reward-preview__benefit { max-width: 190px; color: var(--accent); font-size: 15px; line-height: 1.4; text-align: right; }
.reward-preview > p { margin: 0; padding: 14px 22px; background: var(--surface-raised); color: var(--text-soft); font-size: 13px; }

.dashboard-header { display: flex; justify-content: space-between; align-items: flex-start; gap: 24px; margin-bottom: 30px; }
.dashboard-header h1 { font-size: clamp(26px, 3.2vw, 36px); }
.dashboard-header p { max-width: 660px; margin-bottom: 0; color: var(--text-soft); }
.return-link { margin-top: 4px; }

.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.stat { min-height: 108px; display: flex; align-items: center; gap: 13px; padding: 22px; }
.stat + .stat { border-left: 1px solid var(--border); }
.stat__icon { width: 38px; height: 38px; flex: 0 0 38px; display: grid; place-items: center; border-radius: 7px; background: var(--surface-strong); color: var(--text-soft); font-size: 21px; }
.stat > div { min-width: 0; }
.stat > div span { display: block; color: var(--text-soft); font-size: 13px; }
.stat strong { display: block; overflow: hidden; margin-top: 2px; font-size: clamp(19px, 2.2vw, 25px); text-overflow: ellipsis; white-space: nowrap; }
.stat--accent .stat__icon { background: var(--accent-soft); color: var(--accent); }
.stat--accent strong { color: var(--accent); }

.invite-panel { display: grid; grid-template-columns: minmax(0, 1.55fr) minmax(280px, 0.45fr); margin-top: 20px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.invite-panel__copy { padding: 26px; }
.section-heading p { max-width: 680px; margin-bottom: 0; color: var(--text-soft); }
.invite-panel label { display: block; margin: 24px 0 8px; font-size: 13px; font-weight: 700; }
.copy-field { display: grid; grid-template-columns: minmax(0, 1fr) auto 38px; gap: 8px; }
.copy-field input { width: 100%; min-width: 0; height: 42px; border: 1px solid var(--border-strong); border-radius: 7px; padding: 0 13px; background: var(--surface-raised); color: var(--text); }
.field-help { margin: 9px 0 0; color: var(--text-faint); font-size: 12px; }
.field-help strong { color: var(--text-soft); font-family: "Cascadia Mono", "SFMono-Regular", Consolas, monospace; }
.milestone { display: flex; align-items: flex-start; gap: 14px; padding: 28px 24px; border-left: 1px solid var(--border); background: var(--accent-soft); }
.milestone__icon { width: 40px; height: 40px; flex: 0 0 40px; display: grid; place-items: center; border-radius: 7px; background: var(--surface); color: var(--accent); font-size: 23px; }
.milestone > div > span { display: block; color: var(--accent-strong); font-size: 12px; font-weight: 700; }
.milestone strong { display: block; margin-top: 4px; font-size: 17px; line-height: 1.4; }
.milestone p { margin: 8px 0 0; color: var(--text-soft); font-size: 13px; }

.activity-section { margin-top: 38px; }
.activity-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 12px; }
.segmented { display: inline-grid; grid-template-columns: repeat(3, 1fr); padding: 3px; border: 1px solid var(--border); border-radius: 7px; background: var(--surface-strong); }
.segmented button { min-width: 100px; min-height: 34px; border: 0; border-radius: 5px; background: transparent; color: var(--text-soft); cursor: pointer; font-weight: 650; }
.segmented button[aria-selected="true"] { background: var(--surface); color: var(--text); box-shadow: 0 1px 4px rgba(34, 51, 84, 0.1); }
.filter select { height: 38px; min-width: 126px; border: 1px solid var(--border); border-radius: 7px; padding: 0 32px 0 11px; background: var(--surface); color: var(--text); }
.filter--hidden { display: none; }
.record-list { border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.record-row { min-height: 78px; display: grid; grid-template-columns: minmax(220px, 1.5fr) minmax(150px, 0.65fr) minmax(110px, 0.35fr); align-items: center; gap: 20px; padding: 14px 20px; }
.record-row + .record-row { border-top: 1px solid var(--border); }
.record-person, .reward-type { min-width: 0; display: flex; align-items: center; gap: 12px; }
.record-person > div, .reward-type > div { min-width: 0; }
.record-person strong, .reward-type strong { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.record-person span, .reward-type span, .record-time span { display: block; overflow: hidden; color: var(--text-faint); font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }
.record-avatar { width: 38px; height: 38px; flex: 0 0 38px; display: grid !important; place-items: center; border-radius: 50%; background: var(--surface-strong); color: var(--text-soft) !important; font-size: 14px !important; font-weight: 750; }
.record-time time { display: block; color: var(--text-soft); font-size: 13px; }
.record-status { justify-self: end; }
.status { min-height: 28px; display: inline-flex; align-items: center; gap: 5px; border-radius: 6px; padding: 0 9px; background: var(--surface-strong); color: var(--text-soft); font-size: 12px; font-weight: 700; white-space: nowrap; }
.status i { font-size: 15px; }
.status--qualified { background: var(--success-soft); color: var(--success); }
.status--review, .status--pending { background: var(--warning-soft); color: var(--warning); }
.status--rejected, .status--reversed { background: var(--danger-soft); color: var(--danger); }
.reward-row { grid-template-columns: minmax(240px, 1.5fr) minmax(150px, 0.65fr) minmax(160px, 0.5fr); }
.reward-row > time { color: var(--text-soft); font-size: 13px; }
.reward-icon { width: 38px; height: 38px; flex: 0 0 38px; display: grid !important; place-items: center; border-radius: 7px; background: var(--success-soft); color: var(--success) !important; font-size: 20px !important; }
.reward-icon--negative { background: var(--danger-soft); color: var(--danger) !important; }
.reward-amount { justify-self: end; color: var(--success); font-size: 16px; white-space: nowrap; }
.reward-amount--negative { color: var(--danger); }
.benefit-row { min-height: 92px; display: grid; grid-template-columns: minmax(220px, 1fr) auto minmax(330px, 0.9fr); align-items: center; gap: 18px; padding: 16px 20px; }
.benefit-row + .benefit-row { border-top: 1px solid var(--border); }
.benefit-main { min-width: 0; display: flex; align-items: center; gap: 12px; }
.benefit-main > div { min-width: 0; }
.benefit-main strong { display: block; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.benefit-main span { display: block; color: var(--text-faint); font-size: 12px; }
.benefit-icon { width: 42px; height: 42px; flex: 0 0 42px; display: grid !important; place-items: center; border-radius: 7px; background: var(--accent-soft); color: var(--accent) !important; font-size: 21px !important; }
.benefit-state { justify-self: end; }
.benefit-code { min-width: 0; display: grid; grid-template-columns: minmax(0, 1fr) 38px auto; align-items: center; gap: 8px; }
.benefit-code code { min-width: 0; overflow-x: auto; border: 1px solid var(--border); border-radius: 7px; padding: 8px 10px; background: var(--surface-raised); color: var(--text); font-family: "Cascadia Mono", "SFMono-Regular", Consolas, monospace; font-size: 12px; line-height: 20px; white-space: nowrap; scrollbar-width: thin; user-select: all; }
.benefit-code--empty { display: block; color: var(--text-soft); font-size: 13px; text-align: right; }
.empty-state { min-height: 240px; display: grid; place-items: center; align-content: center; padding: 36px 20px; border: 1px dashed var(--border-strong); border-radius: var(--radius); color: var(--text-soft); text-align: center; }
.empty-state > i { margin-bottom: 12px; color: var(--text-faint); font-size: 34px; }
.empty-state strong { color: var(--text); font-size: 16px; }
.empty-state p { max-width: 420px; margin: 5px 0 0; font-size: 13px; }

.rules-section { margin-top: 46px; padding-top: 28px; border-top: 1px solid var(--border); }
.rules-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 28px; margin-top: 18px; }
.rules-grid details { border-bottom: 1px solid var(--border); }
.rules-grid summary { min-height: 52px; display: flex; align-items: center; justify-content: space-between; gap: 16px; cursor: pointer; list-style: none; font-weight: 700; }
.rules-grid summary::-webkit-details-marker { display: none; }
.rules-grid summary i { color: var(--text-faint); transition: transform 160ms ease; }
.rules-grid details[open] summary i { transform: rotate(180deg); }
.rules-grid details p { margin: -2px 0 16px; color: var(--text-soft); font-size: 13px; }

.toast { position: fixed; left: 50%; bottom: max(24px, env(safe-area-inset-bottom)); z-index: 30; transform: translateX(-50%); min-width: 180px; max-width: calc(100vw - 32px); border: 1px solid color-mix(in srgb, var(--text) 20%, transparent); border-radius: 7px; padding: 10px 16px; background: var(--text); color: var(--surface); box-shadow: var(--shadow); text-align: center; font-size: 13px; font-weight: 650; }
.error-view { min-height: calc(100dvh - var(--topbar-height) - 150px); display: grid; place-items: center; align-content: center; text-align: center; }
.error-view__icon { width: 54px; height: 54px; display: grid; place-items: center; border-radius: 50%; background: var(--danger-soft); color: var(--danger); font-size: 28px; }
.error-view h1 { margin: 18px 0 8px; font-size: 24px; }
.error-view p { max-width: 460px; color: var(--text-soft); }
.error-view .button { margin-top: 8px; }

.skeleton__line, .skeleton__stats div, .skeleton__panel { background: var(--surface-strong); }
.skeleton__line { height: 14px; margin-bottom: 12px; border-radius: 4px; }
.skeleton__line--short { width: 90px; }
.skeleton__line--title { width: min(520px, 80%); height: 38px; }
.skeleton__stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; margin-top: 34px; border-radius: var(--radius); overflow: hidden; }
.skeleton__stats div { height: 108px; background: var(--surface-strong); }
.skeleton__panel { height: 230px; margin-top: 20px; border-radius: var(--radius); }

.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

@media (prefers-reduced-motion: no-preference) {
  .skeleton__line, .skeleton__stats div, .skeleton__panel { animation: pulse 1.4s ease-in-out infinite alternate; }
  @keyframes pulse { from { opacity: 0.55; } to { opacity: 1; } }
}

@media (max-width: 900px) {
  .login-view { grid-template-columns: 1fr; align-content: center; padding: 46px 0; }
  .reward-preview { width: min(100%, 560px); }
  .stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat:nth-child(3) { border-left: 0; border-top: 1px solid var(--border); }
  .stat:nth-child(4) { border-top: 1px solid var(--border); }
  .invite-panel { grid-template-columns: 1fr; }
  .milestone { border-top: 1px solid var(--border); border-left: 0; }
  .benefit-row { grid-template-columns: minmax(220px, 1fr) auto; }
  .benefit-code { grid-column: 1 / -1; }
  .benefit-code--empty { text-align: left; }
}

@media (max-width: 680px) {
  .topbar__inner, .page-shell { width: min(100% - 28px, 1180px); }
  .page-shell { padding-top: 28px; }
  .brand__name { display: none; }
  .account__name { max-width: 110px; }
  .dashboard-header { display: block; }
  .return-link { margin-top: 16px; }
  .stats { grid-template-columns: 1fr 1fr; }
  .stat { min-height: 94px; padding: 16px; }
  .stat__icon { display: none; }
  .copy-field { grid-template-columns: 1fr 42px; }
  .copy-field input { grid-column: 1 / -1; }
  .copy-field .button { grid-column: 1; }
  .copy-field .icon-button { grid-column: 2; }
  .activity-toolbar { align-items: stretch; flex-direction: column; }
  .segmented { display: grid; }
  .segmented button { min-height: 44px; min-width: 0; }
  .filter select { width: 100%; }
  .filter--hidden { display: none; }
  .record-row, .reward-row { grid-template-columns: minmax(0, 1fr) auto; gap: 10px 14px; padding: 14px; }
  .record-time { grid-column: 1; padding-left: 50px; }
  .record-status { grid-column: 2; grid-row: 1 / span 2; }
  .reward-row > time { grid-column: 1; padding-left: 50px; }
  .reward-amount { grid-column: 2; grid-row: 1 / span 2; }
  .benefit-row { grid-template-columns: minmax(0, 1fr) auto; gap: 12px; padding: 14px; }
  .benefit-code { grid-template-columns: minmax(0, 1fr) 44px auto; }
  .benefit-code .icon-button { width: 44px; height: 44px; }
  .benefit-code .button { min-height: 44px; }
  .rules-grid { grid-template-columns: 1fr; gap: 0; }
  .skeleton__stats { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 420px) {
  .brand__product { display: none; }
  .brand__divider { display: none; }
  .login-actions .button { width: 100%; }
  .invite-panel__copy { padding: 20px 16px; }
  .milestone { padding: 22px 16px; }
  .record-row, .reward-row { grid-template-columns: 1fr; }
  .record-time, .reward-row > time { padding-left: 50px; }
  .record-status, .reward-amount { grid-column: 1; grid-row: auto; justify-self: start; margin-left: 50px; }
  .benefit-row { grid-template-columns: 1fr; }
  .benefit-state { justify-self: start; margin-left: 54px; }
  .benefit-code { grid-template-columns: minmax(0, 1fr) 44px; }
  .benefit-code code { grid-column: 1 / -1; }
  .benefit-code .button { grid-column: 1 / -1; }
  .benefit-code--empty { margin-left: 54px; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --page: #111723;
    --surface: #182131;
    --surface-raised: #1c2637;
    --surface-strong: #242f42;
    --text: #edf1f8;
    --text-soft: #b3bfd1;
    --text-faint: #8c9ab0;
    --border: #2e3a4e;
    --border-strong: #3a485e;
    --accent: #6f9ef4;
    --accent-strong: #8aaff5;
    --accent-soft: #1f3356;
    --success: #7fd0a8;
    --success-soft: #193a31;
    --warning: #e5b66c;
    --warning-soft: #3c3021;
    --danger: #ef9299;
    --danger-soft: #42282d;
    --shadow: 0 18px 48px rgba(3, 8, 16, 0.3);
  }
  .brand__mark, .button--primary { color: #101725; }
  .segmented button[aria-selected="true"] { box-shadow: 0 1px 4px rgba(3, 8, 16, 0.3); }
}