:root {
  --g-bg: #f6f8fc;
  --g-sidebar: #eaf1fb;
  --g-chip: #d3e3fd;
  --g-compose: #c2e7ff;
  --g-text: #202124;
  --g-muted: #5f6368;
  --g-line: #e0e3e7;
  --g-blue: #0b57d0;
  --g-red: #c5221f;
  --g-white: #fff;
  --g-hover: #e8eaed;
  --g-shadow: 0 1px 2px rgba(60, 64, 67, .15), 0 1px 3px 1px rgba(60, 64, 67, .12);
  --sans: "Google Sans", Roboto, "Noto Sans SC", "Segoe UI", Arial, sans-serif;
}
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: var(--sans);
  background: var(--g-bg);
  color: var(--g-text);
}
a { color: inherit; text-decoration: none; }
button, input, textarea { font: inherit; }
.g-top {
  height: 64px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 12px;
  padding: 0 12px 0 8px;
  background: var(--g-bg);
}
.g-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  color: var(--g-muted);
  padding: 0 8px;
  min-width: 180px;
}
.g-mark {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: var(--g-blue);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
  font-size: 18px;
}
.g-search {
  max-width: 720px;
  background: var(--g-sidebar);
  border-radius: 24px;
  display: flex;
  align-items: center;
  padding: 0 16px;
  height: 46px;
}
.g-search input {
  border: 0;
  background: transparent;
  width: 100%;
  outline: none;
  color: var(--g-text);
}
.g-who {
  color: var(--g-muted);
  font-size: 13px;
  padding: 8px 12px;
  border-radius: 16px;
  background: var(--g-white);
  display: flex;
  align-items: center;
  gap: 8px;
}
.g-body {
  display: grid;
  grid-template-columns: 256px 1fr;
  height: calc(100vh - 64px);
}
.g-nav {
  padding: 8px 12px 24px;
}
.g-compose {
  width: 142px;
  height: 56px;
  border: 0;
  border-radius: 16px;
  background: var(--g-compose);
  color: var(--g-text);
  font-weight: 500;
  box-shadow: var(--g-shadow);
  cursor: pointer;
  margin: 0 0 16px 4px;
}
.g-compose:hover { filter: brightness(.97); }
.g-nav a, .g-nav button.nav {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  border: 0;
  background: transparent;
  text-align: left;
  padding: 0 20px 0 26px;
  height: 32px;
  border-radius: 0 16px 16px 0;
  color: var(--g-text);
  cursor: pointer;
}
.g-nav a.on, .g-nav button.nav.on {
  background: var(--g-chip);
  font-weight: 600;
}
.g-nav a:hover, .g-nav button.nav:hover { background: var(--g-hover); }
.g-main {
  display: grid;
  grid-template-columns: 360px 1fr;
  background: var(--g-white);
  border-radius: 16px 0 0 0;
  overflow: hidden;
  min-width: 0;
}
.g-list {
  border-right: 1px solid var(--g-line);
  overflow: auto;
}
.g-toolbar {
  height: 48px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 12px;
  border-bottom: 1px solid var(--g-line);
  color: var(--g-muted);
  font-size: 13px;
}
.g-thread {
  width: 100%;
  border: 0;
  background: transparent;
  display: grid;
  gap: 2px;
  text-align: left;
  padding: 12px 16px;
  border-bottom: 1px solid var(--g-line);
  cursor: pointer;
  color: var(--g-text);
}
.g-thread:hover { background: #f2f6fc; }
.g-thread.on { background: #d3e3fd; }
.g-thread .from { font-weight: 600; font-size: 14px; }
.g-thread .sub { font-size: 14px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.g-thread .preview { color: var(--g-muted); font-size: 13px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.g-read { overflow: auto; padding: 8px 28px 40px; min-width: 0; }
.g-read h1 { font-size: 22px; font-weight: 400; margin: 16px 0 20px; }
.g-msg { border-bottom: 1px solid var(--g-line); padding: 16px 0; }
.g-msg .meta { color: var(--g-muted); font-size: 12px; margin-bottom: 8px; }
.g-msg pre {
  white-space: pre-wrap;
  margin: 0;
  font-family: var(--sans);
  line-height: 1.55;
}
.g-empty {
  color: var(--g-muted);
  padding: 48px 24px;
  text-align: center;
}
.g-card {
  max-width: 560px;
  margin: 48px auto;
  background: var(--g-white);
  border-radius: 16px;
  padding: 28px;
  box-shadow: var(--g-shadow);
}
.g-card h1 { font-size: 28px; font-weight: 400; margin: 0 0 8px; }
.g-card p { color: var(--g-muted); }
.g-card label { display: grid; gap: 6px; font-size: 13px; color: var(--g-muted); margin: 16px 0; }
.g-card input, .g-card textarea {
  border: 1px solid #747775;
  border-radius: 4px;
  padding: 12px;
  width: 100%;
}
.g-primary {
  background: var(--g-blue);
  color: #fff;
  border: 0;
  border-radius: 20px;
  padding: 10px 24px;
  cursor: pointer;
}
.g-ghost {
  border: 1px solid var(--g-line);
  background: transparent;
  border-radius: 20px;
  padding: 10px 24px;
  cursor: pointer;
}
.g-actions { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 16px; }
.ok { color: #188038; }
.error { color: var(--g-red); }
.meta { color: var(--g-muted); font-size: 13px; }
dialog.g-compose-dlg {
  border: 0;
  border-radius: 8px 8px 0 0;
  width: min(580px, calc(100vw - 24px));
  padding: 0;
  box-shadow: 0 8px 28px rgba(0,0,0,.28);
}
dialog.g-compose-dlg::backdrop { background: transparent; }
.g-compose-hd {
  background: #404040;
  color: #fff;
  padding: 10px 16px;
  font-weight: 500;
}
.g-compose-bd { display: grid; }
.g-compose-bd input, .g-compose-bd textarea {
  border: 0;
  border-bottom: 1px solid var(--g-line);
  padding: 10px 16px;
  outline: none;
}
.g-compose-bd textarea { min-height: 180px; resize: vertical; }
.g-compose-ft { padding: 12px 16px; }
.g-send { background: var(--g-blue); color: #fff; border: 0; border-radius: 20px; padding: 8px 22px; cursor: pointer; }
@media (max-width: 900px) {
  .g-body { grid-template-columns: 1fr; }
  .g-nav { display: none; }
  .g-main { grid-template-columns: 1fr; }
}