:root {
  --bg: #0d1117;
  --bg-panel: #161b22;
  --bg-hover: #21262d;
  --border: #30363d;
  --text: #c9d1d9;
  --text-dim: #8b949e;
  --accent: #2f81f7;
  --accent-hover: #388bfd;
  --danger: #f85149;
  --term-bg: #000000;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
}

button {
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--bg-hover);
  color: var(--text);
  border-radius: 6px;
  padding: 6px 12px;
  font-size: 13px;
  transition: background .15s, border-color .15s;
}
button:hover { background: #30363d; }
button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
button.primary:hover { background: var(--accent-hover); }
button.danger { color: var(--danger); }
button.danger:hover { border-color: var(--danger); }
button.ghost { background: transparent; }
button.pill { border-radius: 999px; }
button:disabled { opacity: .5; cursor: not-allowed; }

/* ---------- login ---------- */
.login-wrap {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(1200px 600px at 50% -10%, #1c2b44 0%, var(--bg) 55%);
}
.login-card {
  width: 320px;
  background: var(--bg-panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  box-shadow: 0 12px 40px rgba(0,0,0,.5);
}
.login-logo { font-size: 26px; font-weight: 700; letter-spacing: .5px; }
.login-logo .dot { color: var(--accent); }
.login-sub { color: var(--text-dim); margin-top: -10px; font-size: 13px; }
.login-card input {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  padding: 10px 12px;
  font-size: 14px;
  outline: none;
}
.login-card input:focus { border-color: var(--accent); }
.login-error {
  color: var(--danger);
  font-size: 13px;
  text-align: center;
  padding: 4px 0;
}

/* ---------- layout ---------- */
#appView { display: flex; height: 100%; }
#appView[hidden] { display: none; }

#sidebar {
  width: 220px;
  flex: 0 0 220px;
  background: var(--bg-panel);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-height: 0;
}
.brand {
  padding: 14px 14px 10px;
  font-size: 13px;
  font-weight: 700;
  color: var(--text-dim);
  letter-spacing: .4px;
  display: flex;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid var(--border);
}
.brand .dot { color: var(--accent); font-size: 15px; }

.session-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-height: 0;
}
.session-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 6px;
  cursor: pointer;
  border: 1px solid transparent;
  user-select: none;
}
.session-item:hover { background: var(--bg-hover); }
.session-item.active {
  background: rgba(47,129,247,.12);
  border-color: var(--accent);
}
.session-item .name {
  flex: 1;
  font-family: "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 13px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.session-item .meta { color: var(--text-dim); font-size: 11px; flex: 0 0 auto; }
.session-item .meta .wins { margin-right: 6px; }
.session-empty { color: var(--text-dim); text-align: center; padding: 24px 8px; font-size: 13px; }

.sidebar-footer {
  border-top: 1px solid var(--border);
  padding: 10px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ---------- main ---------- */
#main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
#topbar {
  height: 44px;
  flex: 0 0 44px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px 0 16px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
}
#currentSession {
  font-family: "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 13px;
  color: var(--text-dim);
}
#currentSession.on { color: var(--text); }
#currentSession .sess { color: var(--accent); font-weight: 600; }
.topbar-actions { display: flex; gap: 8px; align-items: center; }

#termHost {
  flex: 1;
  min-height: 0;
  position: relative;
  padding: 10px 0 0 12px;
  background: var(--term-bg);
}
#termHost .xterm { height: 100%; }
#termHost .xterm .xterm-viewport { background: var(--term-bg) !important; }

/* ---------- toast ---------- */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg-panel);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 18px;
  border-radius: 8px;
  box-shadow: 0 8px 24px rgba(0,0,0,.4);
  z-index: 50;
  font-size: 13px;
  max-width: 80vw;
}
.toast.error { border-color: var(--danger); color: var(--danger); }
.toast.ok { border-color: #2ea043; }

/* overlay for disconnected state */
#disconnectOverlay {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.75);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  z-index: 20;
}
#disconnectOverlay .msg { color: var(--text); font-size: 15px; }