:root {
  --bg: #f5f6f8; --panel: #ffffff; --border: #e3e6ea; --text: #1d2330; --muted: #6a7385;
  --accent: #2a6df4; --accent-ink: #ffffff; --accent-soft: #e8f0fe; --danger: #c9302c;
  --unread: #f0f6ff; --radius: 8px; --shadow: 0 8px 30px rgba(20, 30, 60, .18);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171c; --panel: #1c2027; --border: #2b313b; --text: #e6e9ef; --muted: #8f98a8;
    --accent: #5b8cff; --accent-ink: #0b1220; --accent-soft: #232f4a; --danger: #ff6b66;
    --unread: #212836; --shadow: 0 8px 30px rgba(0, 0, 0, .5);
  }
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body { font: 14px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; color: var(--text); background: var(--bg); }
.hidden { display: none !important; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.error { color: var(--danger); min-height: 1.2em; margin: 4px 0; }
button, input, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }

.btn, .primary {
  border: 1px solid var(--border); background: var(--panel); border-radius: var(--radius);
  padding: 6px 12px; display: inline-flex; align-items: center;
}
.btn:hover { background: var(--accent-soft); }
.btn.danger { color: var(--danger); }
.primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); font-weight: 600; }
.primary:hover { filter: brightness(1.08); }
.primary:disabled { opacity: .6; cursor: default; }
.link-btn { background: none; border: 0; color: var(--accent); padding: 2px 4px; }
.link-btn:hover { text-decoration: underline; }
.danger-text { color: var(--danger); }
.icon-btn { background: none; border: 0; font-size: 20px; padding: 2px 8px; border-radius: 6px; color: var(--muted); }
.icon-btn:hover { background: var(--accent-soft); color: var(--text); }
input[type=text], input[type=email], input[type=password], input[type=search], textarea {
  width: 100%; border: 1px solid var(--border); border-radius: var(--radius); padding: 8px 10px; background: var(--panel);
}
input:focus, textarea:focus, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 1px; }

.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 18px; }
.logo { display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 8px; background: var(--accent); color: var(--accent-ink); font-size: 16px; }

/* login */
.login { min-height: 100%; display: grid; place-items: center; padding: 16px; }
.login-card { width: 100%; max-width: 360px; background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 28px; box-shadow: var(--shadow); display: grid; gap: 12px; }
.login-card h1 { margin: 6px 0 0; font-size: 20px; }
.login-card label { display: grid; gap: 4px; font-weight: 600; font-size: 12px; color: var(--muted); }

/* app shell */
.app { height: 100%; display: flex; flex-direction: column; }
.topbar { display: flex; align-items: center; gap: 14px; padding: 8px 16px; background: var(--panel); border-bottom: 1px solid var(--border); }
.search { flex: 1; max-width: 560px; }
.spacer { flex: 1; }
.user-menu { display: flex; align-items: center; gap: 10px; }
.layout { flex: 1; display: grid; grid-template-columns: 220px minmax(300px, 420px) 1fr; min-height: 0; }

.sidebar { padding: 14px 10px; border-right: 1px solid var(--border); background: var(--panel); display: flex; flex-direction: column; gap: 10px; overflow: auto; }
.compose { width: 100%; justify-content: center; padding: 10px; }
#folder-nav { display: grid; gap: 2px; }
.folder { display: flex; justify-content: space-between; align-items: center; padding: 7px 10px; border-radius: 8px; cursor: pointer; border: 0; background: none; text-align: left; width: 100%; }
.folder:hover { background: var(--accent-soft); }
.folder.active { background: var(--accent-soft); color: var(--accent); font-weight: 700; }
.badge { background: var(--accent); color: var(--accent-ink); border-radius: 10px; font-size: 11px; padding: 1px 7px; font-weight: 700; }
.quota { margin-top: auto; font-size: 12px; }

.list-pane { display: flex; flex-direction: column; min-height: 0; border-right: 1px solid var(--border); background: var(--panel); }
.list-head { display: flex; justify-content: space-between; align-items: center; padding: 10px 14px; border-bottom: 1px solid var(--border); }
.list-head h2 { margin: 0; font-size: 16px; }
.pager { display: flex; align-items: center; gap: 2px; }
.message-list { list-style: none; margin: 0; padding: 0; overflow: auto; flex: 1; }
.msg { padding: 10px 14px; border-bottom: 1px solid var(--border); cursor: pointer; display: grid; gap: 2px; }
.msg:hover { background: var(--accent-soft); }
.msg.selected { background: var(--accent-soft); box-shadow: inset 3px 0 0 var(--accent); }
.msg.unread { background: var(--unread); }
.msg.unread .m-from, .msg.unread .m-subject { font-weight: 700; }
.msg-top { display: flex; justify-content: space-between; gap: 8px; }
.m-from { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.m-date { color: var(--muted); font-size: 12px; white-space: nowrap; }
.m-subject { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.m-snippet { color: var(--muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 13px; }
.star { color: var(--muted); margin-right: 4px; }
.star.on { color: #e9a400; }
.empty { color: var(--muted); text-align: center; padding: 48px 16px; }

.reader { padding: 18px 24px; overflow: auto; min-width: 0; }
.reader-toolbar { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 14px; }
#r-subject { margin: 0 0 10px; font-size: 20px; overflow-wrap: anywhere; }
.r-meta { padding-bottom: 12px; border-bottom: 1px solid var(--border); margin-bottom: 12px; }
.attachments { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0; }
.chip { display: inline-flex; gap: 6px; align-items: center; border: 1px solid var(--border); border-radius: 16px; padding: 4px 10px; background: var(--panel); font-size: 13px; }
.chip button { background: none; border: 0; padding: 0; color: var(--muted); font-size: 16px; line-height: 1; }
.images-bar { background: var(--accent-soft); border-radius: var(--radius); padding: 8px 12px; margin: 8px 0; font-size: 13px; }
.r-body iframe { width: 100%; border: 0; background: #fff; border-radius: 6px; min-height: 200px; }
.r-body pre { white-space: pre-wrap; word-wrap: break-word; font: inherit; margin: 0; }

/* compose */
.compose-dialog { border: 0; border-radius: 12px; padding: 0; width: min(680px, 96vw); background: var(--panel); color: var(--text); box-shadow: var(--shadow); }
.compose-dialog::backdrop { background: rgba(10, 15, 30, .45); }
#compose-form { display: grid; gap: 8px; padding: 14px 16px 16px; }
.compose-head { display: flex; justify-content: space-between; align-items: center; }
.row { display: grid; grid-template-columns: 64px 1fr; align-items: center; gap: 8px; }
.row span { color: var(--muted); font-size: 12px; font-weight: 600; }
#c-body { min-height: 260px; resize: vertical; }
.compose-foot { display: flex; gap: 8px; align-items: center; }
.compose-foot .danger-text { margin-left: auto; }
.attach-label { cursor: pointer; }

.toast { position: fixed; bottom: 20px; left: 50%; transform: translateX(-50%); background: var(--text); color: var(--bg); padding: 10px 16px; border-radius: 8px; box-shadow: var(--shadow); z-index: 50; max-width: 90vw; }

.only-mobile { display: none; }
@media (max-width: 900px) {
  .only-mobile { display: inline-flex; }
  .user-menu .muted { display: none; }
  .layout { grid-template-columns: 1fr; position: relative; }
  .sidebar { position: absolute; z-index: 10; inset: 0 25% 0 0; transform: translateX(-100%); transition: transform .2s; box-shadow: var(--shadow); }
  .sidebar.open { transform: none; }
  .reader { position: absolute; inset: 0; background: var(--bg); z-index: 5; display: none; padding: 12px 14px; }
  .layout.reading .reader { display: block; }
}