/* Internal tool: readable and fast to scan beats decorative. */
:root {
  --bg: #f0f2f5;
  --panel: #ffffff;
  --line: #e4e6eb;
  --text: #111b21;
  --muted: #667781;
  --accent: #128c7e;
  --accent-dark: #0e6b60;
  --inbound: #ffffff;
  --outbound: #d9fdd3;
  --danger: #c62828;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font: 14px/1.45 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
}

.hidden { display: none !important; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
.error { color: var(--danger); font-size: 12px; margin: 0; }

button {
  font: inherit;
  cursor: pointer;
  border: 0;
  border-radius: 6px;
  padding: 8px 14px;
  background: var(--accent);
  color: #fff;
}
button:hover { background: var(--accent-dark); }
button:disabled { opacity: .55; cursor: default; }
button.ghost { background: transparent; color: var(--accent); padding: 6px 10px; }
button.ghost:hover { background: rgba(18,140,126,.08); }

input, textarea, select {
  font: inherit;
  width: 100%;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: inherit;
}
textarea { resize: vertical; }

/* --- login --------------------------------------------------------------- */
.login { display: grid; place-items: center; height: 100vh; }
.login-card {
  background: var(--panel);
  padding: 28px;
  border-radius: 10px;
  width: min(360px, 92vw);
  box-shadow: 0 2px 12px rgba(0,0,0,.08);
  display: grid;
  gap: 10px;
}
.login-card h1 { margin: 0; font-size: 20px; }
.login-card p { margin: 0; }
.login-card label { font-size: 12px; color: var(--muted); }

/* --- layout -------------------------------------------------------------- */
.app { display: grid; grid-template-columns: 340px 1fr; height: 100vh; }

.sidebar {
  background: var(--panel);
  border-right: 1px solid var(--line);
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-height: 0;
}
.sidebar-head { padding: 12px; border-bottom: 1px solid var(--line); display: grid; gap: 8px; }
.row { display: flex; align-items: center; justify-content: space-between; }
.filters { display: flex; gap: 6px; }
.chip {
  background: #eef0f2; color: var(--muted); padding: 4px 12px;
  border-radius: 999px; font-size: 12px;
}
.chip.active { background: var(--accent); color: #fff; }

.conversations { list-style: none; margin: 0; padding: 0; overflow-y: auto; min-height: 0; }
.conversations li {
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
  cursor: pointer;
  display: grid;
  gap: 2px;
}
.conversations li:hover { background: #f5f6f7; }
.conversations li.active { background: #e9f5f3; }
.conv-top { display: flex; justify-content: space-between; gap: 8px; align-items: baseline; }
.conv-name { font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.conv-time { font-size: 11px; color: var(--muted); flex: none; }
.conv-preview {
  color: var(--muted); font-size: 13px;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.unread {
  background: var(--accent); color: #fff; border-radius: 999px;
  padding: 0 7px; font-size: 11px; font-weight: 600; margin-left: 6px;
}
.sidebar-foot { padding: 8px 12px; border-top: 1px solid var(--line); font-size: 11px; color: var(--muted); }

/* --- thread -------------------------------------------------------------- */
.main { min-width: 0; display: grid; }
.empty { display: grid; place-content: center; text-align: center; gap: 4px; }
.thread { display: grid; grid-template-rows: auto 1fr auto; min-height: 0; }

.thread-head {
  background: var(--panel); border-bottom: 1px solid var(--line);
  padding: 10px 16px; display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.thread-title { font-weight: 600; }
.thread-actions { display: flex; align-items: center; gap: 8px; }
.thread-actions select { width: auto; }
.badge { font-size: 11px; padding: 3px 9px; border-radius: 999px; background: #eef0f2; color: var(--muted); }
.badge.open { background: #e3f5e8; color: #1b7a3d; }
.badge.closed { background: #fdeaea; color: var(--danger); }

.messages {
  overflow-y: auto; min-height: 0; padding: 16px;
  display: flex; flex-direction: column; gap: 6px;
  background: #efeae2;
}
.msg { max-width: min(70%, 620px); padding: 7px 10px; border-radius: 8px; background: var(--inbound); }
.msg.outbound { align-self: flex-end; background: var(--outbound); }
.msg.inbound { align-self: flex-start; }
.msg-body { white-space: pre-wrap; overflow-wrap: anywhere; }
.msg-meta { font-size: 11px; color: var(--muted); text-align: right; margin-top: 2px; display: flex; gap: 6px; justify-content: flex-end; }
.msg.failed { border: 1px solid var(--danger); }
.msg-error { color: var(--danger); font-size: 11px; margin-top: 2px; }
.msg-kind { font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: .04em; }
.msg img { max-width: 100%; border-radius: 6px; display: block; margin-top: 4px; }
.msg a { color: var(--accent-dark); }
.tick.read { color: #1e88e5; }
.day-sep { align-self: center; background: rgba(255,255,255,.85); color: var(--muted); font-size: 11px; padding: 3px 10px; border-radius: 999px; margin: 6px 0; }

/* --- composer ------------------------------------------------------------ */
.composer { background: var(--panel); border-top: 1px solid var(--line); padding: 10px 12px; display: grid; gap: 8px; }
.composer-tabs { display: flex; gap: 6px; }
.tab { background: transparent; color: var(--muted); padding: 4px 10px; font-size: 12px; border-radius: 999px; }
.tab.active { background: #e9f5f3; color: var(--accent-dark); font-weight: 600; }
.pane { display: grid; gap: 6px; }
.composer-foot { display: flex; justify-content: space-between; align-items: center; gap: 12px; }

/* --- dialog -------------------------------------------------------------- */
dialog { border: 0; border-radius: 10px; padding: 20px; width: min(420px, 92vw); }
dialog::backdrop { background: rgba(0,0,0,.35); }
dialog form { display: grid; gap: 8px; }
dialog h2 { margin: 0 0 4px; font-size: 17px; }
dialog label { font-size: 12px; color: var(--muted); }
dialog menu { display: flex; justify-content: flex-end; gap: 8px; margin: 8px 0 0; padding: 0; }

@media (max-width: 760px) {
  .app { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .app.viewing-list .sidebar { display: grid; }
  .app.viewing-list .main { display: none; }
}