:root {
  --bg: #f6f7f8;
  --pane: #ffffff;
  --line: #ececee;
  --line-strong: #e0e2e6;
  --text: #191b1f;
  --muted: #878e99;
  --faint: #b3b8c2;
  --green: #0fa958;
  --green-deep: #0c8f4b;
  --green-soft: #e8f6ee;
  --green-line: #cdebda;
  --danger: #e5484d;
  --radius: 12px;
  --font: -apple-system, "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
  --mono: ui-monospace, "Cascadia Mono", Consolas, monospace;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font-family: var(--font); font-size: 14px; overflow: hidden; }
button, input, select { font: inherit; color: inherit; }
button { cursor: pointer; }
.is-hidden { display: none !important; }
::selection { background: var(--green-soft); }

/* ── 登录 ─────────────────────────────── */
.login-layer { display: grid; place-items: center; min-height: 100vh; padding: 20px; }
.login-card {
  width: min(360px, 100%); padding: 34px 30px 28px; background: var(--pane);
  border: 1px solid var(--line); border-radius: 16px; text-align: center;
  box-shadow: 0 10px 40px rgba(20, 30, 25, .06);
}
.login-logo svg { width: 40px; height: 40px; color: var(--green); }
.login-card h1 { margin: 12px 0 4px; font-size: 22px; }
.login-card > p { margin: 0 0 22px; color: var(--muted); font-size: 13px; }
.login-card input {
  width: 100%; min-height: 44px; margin-bottom: 12px; padding: 10px 13px;
  border: 1px solid var(--line-strong); border-radius: 10px; outline: none; background: #fbfbfc;
  transition: border-color .15s, box-shadow .15s;
}
.login-card input:focus { border-color: var(--green); box-shadow: 0 0 0 3px var(--green-soft); }

/* ── 通用控件 ─────────────────────────── */
.btn {
  min-height: 40px; padding: 0 16px; border: 1px solid var(--line-strong); border-radius: 10px;
  background: var(--pane); font-weight: 600; font-size: 13px; transition: .15s;
}
.btn:hover { border-color: var(--green); color: var(--green-deep); }
.btn-primary { border-color: var(--green); background: var(--green); color: #fff; }
.btn-primary:hover { border-color: var(--green-deep); background: var(--green-deep); color: #fff; }
.btn-block { width: 100%; }
.btn:disabled { opacity: .55; cursor: wait; }
.icon-btn {
  width: 34px; height: 34px; border: 1px solid var(--line); border-radius: 9px;
  background: transparent; color: var(--muted); font-size: 15px; transition: .15s;
}
.icon-btn:hover { color: var(--green-deep); border-color: var(--green-line); background: var(--green-soft); }
.ghost-btn {
  padding: 7px 10px; border: 0; border-radius: 8px; background: transparent;
  color: var(--muted); font-size: 12px;
}
.ghost-btn:hover { background: var(--green-soft); color: var(--green-deep); }
.form-error { margin: 10px 0 0; color: var(--danger); font-size: 12px; }

/* ── 三栏骨架 ─────────────────────────── */
.app-shell { display: grid; grid-template-columns: 252px 400px minmax(0, 1fr); height: calc(100vh - 64px); }
.sidebar, .list-pane, .read-pane { min-height: 0; overflow: hidden; }

/* 侧栏 */
.sidebar { display: flex; flex-direction: column; border-right: 1px solid var(--line); background: var(--pane); padding: 18px 14px 12px; }
.brand { display: flex; align-items: center; gap: 10px; padding: 2px 6px 16px; }
.brand svg { width: 26px; height: 26px; color: var(--green); }
.brand strong { font-size: 19px; letter-spacing: .01em; }
.compose-btn {
  display: flex; align-items: center; justify-content: center; gap: 8px; min-height: 42px;
  border: 1px solid var(--green-line); border-radius: 11px; background: var(--green-soft);
  color: var(--green-deep); font-weight: 600; transition: .15s;
}
.compose-btn:hover { background: #dcefe3; }
.nav-label { display: flex; align-items: center; gap: 8px; padding: 18px 8px 8px; color: var(--muted); font-size: 12px; }
.count-pill { min-width: 20px; padding: 1px 7px; border-radius: 20px; background: var(--bg); color: var(--muted); font: 11px var(--font, sans-serif); text-align: center; }
.address-list { flex: 1; min-height: 0; overflow-y: auto; display: flex; flex-direction: column; gap: 2px; }
.address-item {
  display: flex; align-items: center; gap: 10px; min-height: 40px; padding: 0 10px;
  border: 0; border-radius: 10px; background: transparent; text-align: left; width: 100%;
}
.address-item:hover { background: var(--bg); }
.address-item.active { background: var(--green-soft); }
.address-dot { width: 8px; height: 8px; border-radius: 50%; flex: none; }
.address-item span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 13px; }
.address-item.active span { color: var(--green-deep); font-weight: 600; }
.sidebar-foot { display: flex; gap: 6px; padding-top: 10px; border-top: 1px solid var(--line); }

/* 邮件列表栏 */
.list-pane { display: flex; flex-direction: column; border-right: 1px solid var(--line); background: var(--pane); min-width: 0; }
.list-head {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  padding: 16px 18px 12px; border-bottom: 1px solid var(--line);
}
.list-head h2 { margin: 0; font-size: 19px; word-break: break-all; }
.mail-list { flex: 1; min-height: 0; overflow-y: auto; }
.mail-row {
  display: block; width: 100%; padding: 13px 18px; border: 0; border-bottom: 1px solid var(--line);
  background: transparent; text-align: left;
}
.mail-row:hover { background: #fafbfb; }
.mail-row.active { background: var(--green-soft); }
.mail-row-top { display: flex; justify-content: space-between; gap: 12px; }
.mail-from { font-weight: 700; font-size: 14px; }
.mail-time { color: var(--faint); font-size: 12px; flex: none; }
.mail-subject { margin-top: 3px; color: #3d434b; font-size: 13px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.mail-row.active .mail-subject { color: var(--green-deep); }
.list-empty { padding: 46px 20px; color: var(--faint); text-align: center; font-size: 13px; line-height: 1.8; }

/* 阅读栏 */
.read-pane { display: flex; flex-direction: column; min-width: 0; background: var(--bg); }
.read-empty { flex: 1; display: grid; place-content: center; justify-items: center; gap: 10px; color: var(--faint); }
.read-empty-icon { font-size: 34px; }
.read-body { flex: 1; display: flex; flex-direction: column; padding: 26px 30px 20px; min-height: 0; overflow-y: auto; }
.read-body h1 { margin: 0 0 14px; font-size: 22px; line-height: 1.35; word-break: break-word; }
.mail-meta { display: flex; flex-wrap: wrap; align-items: baseline; gap: 8px 16px; padding-bottom: 16px; border-bottom: 1px solid var(--line); }
.mail-meta strong { font-size: 13px; word-break: break-all; }
.mail-meta span { margin-left: auto; color: var(--muted); font-size: 12px; }
.mail-frame-box { flex: 1; min-height: 320px; margin-top: 18px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--pane); overflow: hidden; }
.mail-frame { display: block; width: 100%; height: 100%; min-height: 320px; border: 0; }
.mail-text { margin: 0; padding: 18px; white-space: pre-wrap; word-break: break-word; font-family: var(--font); font-size: 13px; line-height: 1.7; }
.read-actions { display: flex; justify-content: flex-end; padding-top: 14px; }
.read-actions .btn { color: var(--danger); }
.read-actions .btn:hover { border-color: var(--danger); color: var(--danger); }

/* ── 弹层与提示 ───────────────────────── */
.modal-layer { position: fixed; inset: 0; z-index: 20; display: grid; place-items: center; background: rgba(18, 22, 20, .35); }
.modal-card { width: min(380px, calc(100vw - 32px)); padding: 24px; border-radius: 14px; background: var(--pane); box-shadow: 0 18px 50px rgba(0, 0, 0, .18); }
.modal-card h3 { margin: 0 0 18px; }
.field { display: grid; gap: 7px; margin-bottom: 14px; font-size: 13px; color: #3d434b; }
.field small { color: var(--muted); font-weight: 400; }
.field select, .field input {
  min-height: 42px; padding: 9px 12px; border: 1px solid var(--line-strong); border-radius: 10px;
  outline: none; background: #fbfbfc; transition: border-color .15s, box-shadow .15s;
}
.field select:focus, .field input:focus { border-color: var(--green); box-shadow: 0 0 0 3px var(--green-soft); }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 6px; }

.toast {
  position: fixed; left: 50%; bottom: 26px; z-index: 30; transform: translate(-50%, 12px);
  max-width: min(420px, calc(100vw - 32px)); padding: 11px 16px; border-radius: 10px;
  background: #23272b; color: #fff; font-size: 13px; opacity: 0; pointer-events: none; transition: .18s;
}
.toast.visible { opacity: 1; transform: translate(-50%, 0); }
.toast.error { background: var(--danger); }

/* ── 服务端地址簿与搜索 ───────────────── */
.domain-group-label {
  padding: 14px 10px 6px; color: var(--muted); font-size: 11px; letter-spacing: .04em;
}
.domain-group-label.broken { color: var(--danger); }
.group-note { margin: 0; padding: 2px 10px 8px; color: var(--faint); font-size: 11px; }
.side-filter, .mail-filter {
  width: 100%; min-height: 36px; padding: 8px 11px; border: 1px solid var(--line);
  border-radius: 9px; outline: none; background: var(--bg); font-size: 13px;
  transition: border-color .15s, box-shadow .15s;
}
.side-filter:focus, .mail-filter:focus { border-color: var(--green); background: #fff; box-shadow: 0 0 0 3px var(--green-soft); }
.side-filter { margin: 0 4px 8px; width: calc(100% - 8px); }
.list-tools { padding: 10px 18px; border-bottom: 1px solid var(--line); }
.mail-count-badge {
  margin-left: auto; flex: none; padding: 1px 7px; border-radius: 10px;
  background: var(--bg); color: var(--muted); font-size: 11px;
}
.address-item.active .mail-count-badge { background: #fff; color: var(--green-deep); }
.list-tools + .mail-list .mail-row:first-child { border-top: 0; }

/* ── 写邮件 / 附件 / 设置弹层 ─────────── */
.head-actions { display: flex; gap: 8px; }
.compose-body { flex: 1; display: flex; flex-direction: column; padding: 26px 30px 20px; min-height: 0; overflow-y: auto; }
.compose-body h1 { margin: 0 0 14px; font-size: 22px; }
.compose-meta { display: flex; gap: 10px; align-items: baseline; margin-bottom: 14px; color: var(--muted); font-size: 12px; }
.compose-meta code { color: var(--text); font-family: var(--mono); }
.check-line { display: flex; align-items: center; gap: 8px; margin-bottom: 10px; color: var(--muted); font-size: 12px; }
.check-line input { width: 14px; min-height: 14px; margin: 0; accent-color: var(--green); }
.compose-content {
  width: 100%; padding: 12px; border: 1px solid var(--line-strong); border-radius: 10px;
  background: #fbfbfc; outline: none; font-family: var(--font); font-size: 13px; line-height: 1.6; resize: vertical;
}
.compose-content:focus { border-color: var(--green); box-shadow: 0 0 0 3px var(--green-soft); }
.compose-note { margin: 10px 0 0; color: var(--faint); font-size: 11px; line-height: 1.6; }
.mail-attachments { margin-top: 14px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--pane); padding: 12px 14px; }
.attach-title { color: var(--muted); font-size: 12px; margin-bottom: 8px; }
.attach-item {
  display: inline-block; margin: 0 8px 8px 0; padding: 7px 12px; border: 1px solid var(--line-strong);
  border-radius: 9px; background: var(--pane); color: var(--green-deep); font-size: 12px;
}
.attach-item:hover { border-color: var(--green); background: var(--green-soft); }
.settings-sheet {
  width: min(720px, calc(100vw - 32px)); max-height: calc(100vh - 40px); overflow-y: auto;
  padding: 20px 22px; border-radius: 14px; background: var(--pane); box-shadow: 0 18px 50px rgba(0, 0, 0, .18);
}
.settings-head { display: flex; align-items: center; gap: 12px; margin-bottom: 16px; }
.settings-head h3 { margin: 0; font-size: 17px; flex: 1; }
.settings-backend {
  min-height: 38px; padding: 6px 10px; border: 1px solid var(--line-strong);
  border-radius: 9px; background: #fbfbfc; outline: none; font-size: 13px;
}
.settings-body { display: grid; gap: 16px; }
.settings-block h4 { margin: 0 0 8px; font-size: 13px; }
.settings-block h4 small { color: var(--faint); font-weight: 400; }
.settings-block textarea {
  width: 100%; padding: 10px; border: 1px solid var(--line-strong); border-radius: 10px;
  background: #fbfbfc; outline: none; font: 11px/1.6 var(--mono); color: var(--text);
}
.settings-block textarea:focus { border-color: var(--green); box-shadow: 0 0 0 3px var(--green-soft); }
.settings-actions { margin-top: 8px; }
.settings-note { margin: 8px 0 0; color: var(--muted); font-size: 12px; line-height: 1.6; overflow-wrap: anywhere; }
.settings-note.ok-note { color: var(--green-deep); }
.stat-row { display: flex; justify-content: space-between; padding: 7px 2px; border-bottom: 1px solid var(--line); }
.stat-row:last-child { border-bottom: 0; }
.stat-row span { color: var(--muted); font-size: 12px; }
.stat-row code { font-family: var(--mono); font-size: 13px; }

/* ── 分组展开收起 ─────────────────────── */
.domain-group-label {
  display: flex; align-items: center; gap: 6px; width: 100%; min-height: 30px;
  padding: 4px 10px 2px; border: 0; border-radius: 8px; background: transparent;
  text-align: left; color: var(--muted); font-size: 11px; letter-spacing: .04em;
  cursor: pointer; font-family: inherit;
}
.domain-group-label:hover { color: var(--text); background: var(--bg); }
.domain-group-label.broken { color: var(--danger); cursor: default; }
.group-chevron { flex: none; font-size: 9px; color: var(--faint); }
.group-count { margin-left: auto; flex: none; color: var(--faint); font: 10px var(--mono); }
.groups-toggle-btn { margin-left: auto; padding: 2px 8px; font-size: 11px; }

/* ── 未读 / 加载更多 / 验证码 ─────────── */
.mail-row.unread .mail-from,
.mail-row.unread .mail-subject { font-weight: 800; color: var(--text); }
.mail-row.unread .mail-subject { color: var(--green-deep); }
.load-more {
  display: block; width: 100%; padding: 12px; border: 0; border-top: 1px solid var(--line);
  background: transparent; color: var(--green-deep); font-size: 12px;
}
.load-more:hover { background: var(--green-soft); }
.mail-codes {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-top: 14px;
  padding: 10px 14px; border: 1px dashed var(--green); border-radius: var(--radius); background: var(--green-soft);
}
.code-label { color: var(--green-deep); font-size: 12px; }
.code-chip {
  padding: 5px 12px; border: 1px solid var(--green-line); border-radius: 9px;
  background: #fff; color: var(--green-deep); font: 700 14px var(--mono);
}
.code-chip:hover { background: var(--green-soft); }

/* ── 收藏 ─────────────────────────────── */
.star-mark { flex: none; cursor: pointer; color: var(--faint); font-size: 13px; padding: 2px; }
.star-mark:hover { color: #f0a848; }
.star-mark.on { color: #f0a848; }
.star-toggle.active { color: #f0a848; background: rgba(240, 168, 72, .12); }
.address-item.active .star-mark.on { color: #b8860b; }
.address-delete { flex: none; cursor: pointer; color: var(--faint); font-size: 11px; padding: 2px 3px; border-radius: 5px; }
.address-delete:hover { color: #fff; background: var(--danger); }

/* ── 窄屏 ─────────────────────────────── */
@media (max-width: 980px) {
  .app-shell { grid-template-columns: 220px minmax(0, 1fr); }
  .read-pane { display: none; }
  .read-pane.open { display: flex; position: fixed; inset: 0; z-index: 15; }
}
@media (max-width: 640px) {
  .app-shell { grid-template-columns: minmax(0, 1fr); }
  .sidebar { display: none; }
  .app-shell.show-sidebar .sidebar { display: flex; position: fixed; inset: 0 auto 0 0; width: 260px; z-index: 15; }
}