:root {
  color-scheme: light;
  --bg: #f5f7f8;
  --surface: #ffffff;
  --surface-subtle: #f0f2f4;
  --surface-hover: #e9eef5;
  --text: #202124;
  --text-soft: #5f6368;
  --text-faint: #767b82;
  --border: #dfe3e7;
  --border-strong: #c9cfd6;
  --primary: #1d62d5;
  --primary-hover: #174fae;
  --primary-soft: #e9f1ff;
  --success: #197446;
  --success-soft: #e7f5ec;
  --warning: #9a5b00;
  --danger: #b42318;
  --focus: #1d62d5;
  --shadow: 0 12px 32px rgba(31, 35, 40, 0.09);
  --radius: 8px;
  --header-height: 64px;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  letter-spacing: 0;
}

* { box-sizing: border-box; }

html, body { min-height: 100%; }

body {
  margin: 0;
  min-width: 320px;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

button, input, textarea { font: inherit; letter-spacing: 0; }

button, a { -webkit-tap-highlight-color: transparent; }

button { cursor: pointer; }

button:disabled { cursor: not-allowed; opacity: 0.55; }

button:focus-visible, input:focus-visible, textarea:focus-visible, a:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--focus) 38%, transparent);
  outline-offset: 2px;
}

[hidden] { display: none !important; }

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

.skip-link {
  position: fixed;
  z-index: 50;
  left: 12px;
  top: 12px;
  padding: 10px 14px;
  background: var(--surface);
  color: var(--primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  transform: translateY(-160%);
}

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

.connect-view { min-height: 100dvh; }

.connect-header, .app-header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--surface) 94%, transparent);
}

.connect-header {
  justify-content: space-between;
  padding: 0 clamp(20px, 5vw, 64px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  color: var(--text);
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  grid-template-columns: repeat(2, 8px);
  grid-template-rows: repeat(2, 8px);
  gap: 2px;
  width: 18px;
  height: 18px;
}

.brand-mark i:nth-child(1) { background: #1d62d5; }
.brand-mark i:nth-child(2) { background: #197446; }
.brand-mark i:nth-child(3) { background: #d08300; }
.brand-mark i:nth-child(4) { background: #b42318; }

.read-only-badge {
  padding: 5px 9px;
  border: 1px solid #b8d9c7;
  border-radius: 999px;
  background: var(--success-soft);
  color: var(--success);
  font-size: 13px;
  font-weight: 650;
}

.connect-main {
  min-height: calc(100dvh - var(--header-height));
  display: grid;
  place-items: center;
  padding: 32px 20px;
}

.connect-tool {
  width: 100%;
  max-width: 620px;
  min-width: 0;
  padding: clamp(24px, 4vw, 40px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.connect-title-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}

.eyebrow {
  margin: 0 0 4px;
  color: var(--text-soft);
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
}

h1, h2, p { overflow-wrap: anywhere; }

.connect-tool h1, .inbox-heading h1 {
  margin: 0;
  font-size: 24px;
  line-height: 1.25;
}

.connection-indicator {
  width: 12px;
  height: 12px;
  margin-top: 8px;
  border: 2px solid var(--border-strong);
  border-radius: 50%;
}

form label {
  display: block;
  margin-bottom: 8px;
  color: var(--text);
  font-size: 14px;
  font-weight: 650;
}

.format-line {
  display: flex;
  max-width: 100%;
  min-width: 0;
  gap: 5px;
  margin-bottom: 8px;
  overflow-x: auto;
  color: var(--text-soft);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px;
  white-space: nowrap;
  scrollbar-width: thin;
}

.format-line span:nth-of-type(2) { text-decoration: line-through; }
.format-line b { color: var(--border-strong); }

textarea, .search-field input {
  width: 100%;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border-strong);
}

textarea {
  min-height: 128px;
  padding: 14px;
  resize: vertical;
  border-radius: 6px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
  line-height: 1.6;
}

textarea::placeholder, input::placeholder { color: var(--text-faint); }

.field-hint, .form-error {
  margin: 8px 0 0;
  font-size: 13px;
}

.field-hint { color: var(--text-soft); }
.form-error { min-height: 20px; color: var(--danger); }

.primary-button, .secondary-button, .quiet-button, .back-button {
  min-height: 44px;
  border-radius: 6px;
  font-weight: 650;
  transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease, opacity 180ms ease;
}

.primary-button {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 16px;
  padding: 0 16px;
  border: 1px solid var(--primary);
  background: var(--primary);
  color: #ffffff;
}

.primary-button:hover:not(:disabled) { background: var(--primary-hover); border-color: var(--primary-hover); }

.secondary-button, .quiet-button, .back-button {
  padding: 0 14px;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  color: var(--text);
}

.secondary-button:hover:not(:disabled), .quiet-button:hover:not(:disabled), .back-button:hover:not(:disabled) {
  background: var(--surface-hover);
}

.quiet-button { border-color: transparent; color: var(--text-soft); }

.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
}

.trust-grid div { min-width: 0; }
.trust-grid strong, .trust-grid span { display: block; }
.trust-grid strong { font-size: 13px; }
.trust-grid span { margin-top: 2px; color: var(--text-soft); font-size: 12px; }

.mail-view { min-height: 100dvh; }

.app-header {
  position: relative;
  z-index: 10;
  padding: 0 18px;
}

.compact-brand { width: 200px; flex: 0 0 200px; }

.header-status {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-soft);
  font-size: 13px;
}

.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-radius: 50%;
  background: var(--success);
}

.header-actions { display: flex; gap: 8px; margin-left: auto; }
.header-actions button { min-width: 64px; }

.mail-layout {
  height: calc(100dvh - var(--header-height));
  display: grid;
  grid-template-columns: 220px minmax(340px, 410px) minmax(0, 1fr);
  overflow: hidden;
}

.folder-rail, .inbox-pane, .reader-pane { min-width: 0; }

.folder-rail {
  display: flex;
  flex-direction: column;
  padding: 20px 12px 16px;
  border-right: 1px solid var(--border);
  background: var(--surface-subtle);
}

.account-block {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 0 8px 20px;
}

.account-avatar, .sender-avatar {
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: 50%;
  background: #284b63;
  color: #ffffff;
  font-weight: 700;
}

.account-avatar { width: 36px; height: 36px; }
.account-block div { min-width: 0; }
.account-block strong, .account-block span { display: block; }
.account-block strong { font-size: 13px; }
.account-block span { overflow: hidden; color: var(--text-soft); font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }

.folder-button {
  width: 100%;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--text);
  font-size: 14px;
}

.folder-button.active { background: var(--primary-soft); color: var(--primary); font-weight: 700; }
.folder-button b { font-variant-numeric: tabular-nums; }

.rail-foot {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  padding: 12px 8px 0;
  color: var(--text-soft);
  font-size: 12px;
}

.inbox-pane {
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border);
  background: var(--surface);
  overflow: hidden;
}

.inbox-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 18px 14px;
}

.inbox-heading > span { color: var(--text-soft); font-size: 12px; white-space: nowrap; }

.search-field { display: block; padding: 0 18px 12px; }
.search-field input { height: 42px; padding: 0 12px; border-radius: 6px; font-size: 14px; }

.filter-tabs {
  display: flex;
  gap: 4px;
  padding: 0 18px 12px;
  border-bottom: 1px solid var(--border);
}

.filter-tabs button {
  min-height: 36px;
  padding: 0 12px;
  border: 0;
  border-radius: 6px;
  background: transparent;
  color: var(--text-soft);
  font-size: 13px;
  font-weight: 650;
}

.filter-tabs button:hover { background: var(--surface-subtle); }
.filter-tabs button[aria-selected="true"] { background: var(--surface-subtle); color: var(--text); }

.message-list { flex: 1; overflow-y: auto; }

.message-row {
  width: 100%;
  min-height: 106px;
  display: grid;
  grid-template-columns: 36px minmax(0, 1fr);
  gap: 10px;
  padding: 14px 18px;
  text-align: left;
  border: 0;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  transition: background-color 180ms ease;
}

.message-row:hover, .message-row.selected { background: var(--surface-hover); }
.message-row.unread .message-sender, .message-row.unread .message-subject { font-weight: 750; }

.sender-avatar { width: 36px; height: 36px; font-size: 13px; }

.message-summary { min-width: 0; }
.message-topline { display: flex; align-items: center; gap: 8px; min-width: 0; }
.message-sender { overflow: hidden; flex: 1; font-size: 13px; text-overflow: ellipsis; white-space: nowrap; }
.message-date { flex: 0 0 auto; color: var(--text-faint); font-size: 11px; font-variant-numeric: tabular-nums; }
.message-subject { display: block; margin-top: 3px; overflow: hidden; font-size: 14px; text-overflow: ellipsis; white-space: nowrap; }
.message-preview { display: block; margin-top: 3px; overflow: hidden; color: var(--text-soft); font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }
.message-meta { min-height: 20px; margin-top: 7px; }

.code-chip {
  display: inline-flex;
  align-items: center;
  min-height: 20px;
  padding: 0 7px;
  border-radius: 4px;
  background: var(--success-soft);
  color: var(--success);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 11px;
  font-weight: 750;
}

.unread-mark {
  width: 7px;
  height: 7px;
  display: inline-block;
  border-radius: 50%;
  background: var(--primary);
}

.list-empty {
  display: grid;
  place-items: center;
  min-height: 220px;
  padding: 24px;
  color: var(--text-soft);
  font-size: 14px;
  text-align: center;
}

.skeleton-row { pointer-events: none; }
.skeleton-line { height: 10px; margin-bottom: 9px; border-radius: 3px; background: var(--surface-subtle); }
.skeleton-line.short { width: 42%; }
.skeleton-line.medium { width: 70%; }

.reader-pane { overflow-y: auto; background: var(--surface); }

.reader-empty {
  min-height: 100%;
  display: grid;
  place-content: center;
  justify-items: center;
  padding: 32px;
  color: var(--text-soft);
}

.reader-empty strong { margin-top: 20px; color: var(--text); }
.reader-empty span { margin-top: 4px; font-size: 13px; }

.empty-visual {
  width: 86px;
  height: 64px;
  padding: 14px;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  background: var(--surface-subtle);
}

.empty-visual i { display: block; height: 5px; margin: 0 0 8px; border-radius: 2px; background: var(--border-strong); }
.empty-visual i:nth-child(1) { width: 65%; }
.empty-visual i:nth-child(3) { width: 78%; }

.reader-content { max-width: 880px; margin: 0 auto; padding: 36px clamp(24px, 5vw, 64px) 64px; }
.back-button { display: none; margin-bottom: 20px; }

.reader-header { padding-bottom: 24px; border-bottom: 1px solid var(--border); }
.message-time { margin: 0 0 8px; color: var(--text-soft); font-size: 12px; }
.reader-header h2 { margin: 0; font-size: 28px; line-height: 1.3; }

.sender-line { display: flex; align-items: center; gap: 12px; margin-top: 22px; }
.sender-line .sender-avatar { width: 42px; height: 42px; }
.sender-line div { min-width: 0; }
.sender-line > div strong, .sender-line > div span { display: block; overflow-wrap: anywhere; }
.sender-line strong { font-size: 14px; }
.sender-line span { color: var(--text-soft); font-size: 12px; }

.code-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin: 24px 0;
  padding: 16px 18px;
  border: 1px solid #b8d9c7;
  border-radius: var(--radius);
  background: var(--success-soft);
}

.code-panel span, .code-panel strong { display: block; }
.code-panel span { color: var(--success); font-size: 12px; font-weight: 650; }
.code-panel strong { margin-top: 2px; color: var(--text); font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 26px; font-variant-numeric: tabular-nums; letter-spacing: 0; }

.message-body {
  margin: 28px 0 0;
  min-width: 0;
}

.message-text {
  margin: 0;
  color: var(--text);
  font-family: inherit;
  font-size: 15px;
  line-height: 1.75;
  overflow-wrap: anywhere;
  white-space: pre-wrap;
}

.message-html {
  display: block;
  width: 100%;
  height: 68dvh;
  min-height: 440px;
  max-height: 760px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: #ffffff;
  color-scheme: light;
}

.toast {
  position: fixed;
  z-index: 30;
  right: 20px;
  bottom: 20px;
  max-width: min(360px, calc(100vw - 40px));
  padding: 12px 16px;
  border: 1px solid var(--border-strong);
  border-radius: 6px;
  background: var(--text);
  color: var(--surface);
  box-shadow: var(--shadow);
  font-size: 13px;
}

@media (max-width: 1023px) {
  .compact-brand { width: auto; flex-basis: auto; }
  .mail-layout { grid-template-columns: minmax(320px, 390px) minmax(0, 1fr); }
  .folder-rail { display: none; }
}

@media (max-width: 767px) {
  :root { --header-height: 56px; }
  .connect-header { padding: 0 16px; }
  .connect-main { padding: 20px 12px; align-items: start; }
  .connect-tool { padding: 24px 18px; box-shadow: none; }
  textarea { font-size: 16px; }
  .trust-grid { grid-template-columns: 1fr; gap: 12px; }
  .trust-grid div { display: flex; justify-content: space-between; gap: 16px; }
  .trust-grid span { text-align: right; }
  .app-header { padding: 0 12px; }
  .compact-brand > span:last-child { display: none; }
  .header-status { margin-left: 12px; }
  .header-actions { gap: 2px; }
  .header-actions button { min-width: 54px; padding: 0 8px; }
  .mail-layout { display: block; height: calc(100dvh - var(--header-height)); }
  .inbox-pane, .reader-pane { height: 100%; border: 0; }
  .reader-pane { display: none; }
  .mail-view.mobile-reading .inbox-pane { display: none; }
  .mail-view.mobile-reading .reader-pane { display: block; }
  .message-row { min-height: 112px; padding-inline: 14px; }
  .reader-content { padding: 20px 18px 48px; }
  .reader-header h2 { font-size: 22px; }
  .back-button { display: inline-flex; align-items: center; }
  .code-panel { align-items: flex-end; }
  .message-html { height: 62dvh; min-height: 400px; }
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --bg: #151719;
    --surface: #1d2023;
    --surface-subtle: #23272b;
    --surface-hover: #2a3036;
    --text: #f0f2f4;
    --text-soft: #b7bec6;
    --text-faint: #929aa3;
    --border: #343a40;
    --border-strong: #4a525b;
    --primary: #78aaff;
    --primary-hover: #96bcff;
    --primary-soft: #243b60;
    --success: #70d29b;
    --success-soft: #173a29;
    --warning: #f0b862;
    --danger: #ff8c82;
    --focus: #78aaff;
    --shadow: 0 12px 32px rgba(0, 0, 0, 0.28);
  }
  .read-only-badge, .code-panel { border-color: #2c6b49; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}