* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --bg: #1a1a2e; --surface: #16213e; --border: #0f3460;
  --text: #e0e0e0; --text-dim: #888; --accent: #0ea5e9;
  --user-bg: #0f3460; --bot-bg: #1e293b; --error: #ef4444; --hover: #1e2d4a;
  --activity-w: 44px; --panel-min: 160px; --panel-default: 220px;
}
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; background: var(--bg); color: var(--text); height: 100vh; overflow: hidden; }

/* Login */
.login-overlay { position: fixed; inset: 0; display: flex; align-items: center; justify-content: center; background: var(--bg); z-index: 100; }
.login-box { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 32px; width: 320px; }
.login-box h2 { font-size: 18px; margin-bottom: 20px; text-align: center; }
.login-box input { width: 100%; padding: 10px 12px; margin-bottom: 12px; background: var(--bg); color: var(--text); border: 1px solid var(--border); border-radius: 6px; font-size: 14px; outline: none; }
.login-box input:focus { border-color: var(--accent); }
.login-box button { width: 100%; padding: 10px; background: var(--accent); color: #fff; border: none; border-radius: 6px; font-size: 14px; cursor: pointer; }
.login-box button:disabled { opacity: 0.5; }
.login-box .error { color: var(--error); font-size: 12px; margin-bottom: 8px; min-height: 18px; }

/* App layout */
.app { display: none; height: 100vh; flex-direction: row; }
.app.active { display: flex; }

/* Activity Bar */
.activity-bar { width: var(--activity-w); background: #111827; border-right: 1px solid var(--border); display: flex; flex-direction: column; flex-shrink: 0; }
.activity-icons { flex: 1; display: flex; flex-direction: column; align-items: center; padding-top: 8px; gap: 4px; }
.activity-bottom { display: flex; flex-direction: column; align-items: center; padding-bottom: 8px; gap: 4px; }
.activity-btn { background: none; border: none; color: var(--text-dim); font-size: 18px; width: 36px; height: 36px; border-radius: 6px; cursor: pointer; display: flex; align-items: center; justify-content: center; }
.activity-btn:hover { background: var(--hover); color: var(--text); }
.activity-btn.active { color: var(--accent); background: rgba(14,165,233,0.1); }
.activity-user { font-size: 16px; width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; cursor: default; }

/* Panels */
.panel { background: var(--surface); display: flex; flex-direction: column; flex-shrink: 0; overflow: hidden; }
.panel.collapsed { display: none; }
.panel-left { width: var(--panel-default); border-right: 1px solid var(--border); }
.panel-right { width: var(--panel-default); border-left: 1px solid var(--border); }
.panel-header { padding: 10px 12px; border-bottom: 1px solid var(--border); display: flex; align-items: center; gap: 6px; }
.panel-title { font-size: 12px; color: var(--text-dim); flex: 1; text-transform: uppercase; letter-spacing: 0.5px; font-weight: 600; }
.panel-btn { background: none; border: 1px solid var(--border); color: var(--text-dim); border-radius: 4px; padding: 2px 8px; cursor: pointer; font-size: 14px; line-height: 1; }
.panel-btn:hover { border-color: var(--accent); color: var(--accent); }
.panel-body { flex: 1; overflow-y: auto; padding: 4px 0; }
.panel-section { display: flex; flex-direction: column; }
.panel-section-grow { flex: 1; display: flex; flex-direction: column; overflow: hidden; }
.panel-section-grow .panel-body { flex: 1; overflow-y: auto; }
.panel-divider { height: 1px; background: var(--border); margin: 0; flex-shrink: 0; }

/* Assistant list */
.assistant-item { padding: 8px 12px; cursor: pointer; font-size: 13px; display: flex; align-items: center; gap: 8px; margin: 2px 4px; border-radius: 6px; }
.assistant-item:hover { background: var(--hover); }
.assistant-item .assistant-icon { font-size: 16px; width: 24px; text-align: center; flex-shrink: 0; }
.assistant-item .assistant-info { flex: 1; overflow: hidden; }
.assistant-item .assistant-name { font-weight: 500; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.assistant-item .assistant-desc { font-size: 11px; color: var(--text-dim); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

/* Resize handles */
.resize-handle { width: 4px; cursor: col-resize; background: transparent; flex-shrink: 0; position: relative; z-index: 10; }
.resize-handle:hover, .resize-handle.dragging { background: var(--accent); }
.resize-handle.collapsed { display: none; }

/* Session list */
.session-group { margin-bottom: 4px; }
.session-group-label { font-size: 11px; color: var(--text-dim); padding: 8px 12px 4px; text-transform: uppercase; letter-spacing: 0.5px; }
.session-item { padding: 8px 12px; cursor: pointer; font-size: 13px; display: flex; align-items: center; gap: 6px; margin: 0 4px 1px; border-radius: 6px; }
.session-item:hover { background: var(--hover); }
.session-item.active { background: var(--border); }
.session-item .label { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.session-item .del { visibility: hidden; background: none; border: none; color: var(--text-dim); cursor: pointer; font-size: 12px; padding: 2px 4px; }
.session-item:hover .del { visibility: visible; }
.session-item .del:hover { color: var(--error); }

/* File breadcrumb */
.file-breadcrumb { padding: 6px 12px; font-size: 12px; color: var(--text-dim); border-bottom: 1px solid var(--border); display: flex; align-items: center; gap: 2px; flex-wrap: wrap; min-height: 30px; }
.file-breadcrumb span { cursor: pointer; }
.file-breadcrumb span:hover { color: var(--accent); }
.file-breadcrumb .sep { cursor: default; color: var(--text-dim); }
.file-breadcrumb .sep:hover { color: var(--text-dim); }

/* File list */
.file-item { padding: 6px 12px; cursor: pointer; font-size: 13px; display: flex; align-items: center; gap: 8px; margin: 0 4px 1px; border-radius: 4px; }
.file-item:hover { background: var(--hover); }
.file-item .icon { font-size: 14px; width: 20px; text-align: center; flex-shrink: 0; }
.file-item .name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.file-item .meta { font-size: 11px; color: var(--text-dim); flex-shrink: 0; }
.file-item .actions { visibility: hidden; display: flex; gap: 2px; }
.file-item:hover .actions { visibility: visible; }
.file-item .actions button { background: none; border: none; color: var(--text-dim); cursor: pointer; font-size: 12px; padding: 2px 4px; }
.file-item .actions button:hover { color: var(--accent); }
.file-item .actions button.del-btn:hover { color: var(--error); }
.file-empty { padding: 20px 12px; text-align: center; color: var(--text-dim); font-size: 13px; }

/* Center: Chat */
.center { flex: 1; display: flex; flex-direction: column; min-width: 300px; }
.center-header { padding: 10px 20px; background: var(--surface); border-bottom: 1px solid var(--border); display: flex; align-items: center; gap: 12px; font-size: 13px; }
.center-header .session-title { font-weight: 600; flex: 1; }
.center-header .status { color: var(--text-dim); }
.center-header .status.connected { color: #22c55e; }
.messages { flex: 1; overflow-y: auto; padding: 20px; display: flex; flex-direction: column; gap: 16px; }
.msg { max-width: 80%; padding: 12px 16px; border-radius: 12px; font-size: 14px; line-height: 1.6; word-break: break-word; }
.msg.user { align-self: flex-end; background: var(--user-bg); border-bottom-right-radius: 4px; white-space: pre-wrap; }
.msg.assistant { align-self: flex-start; background: var(--bot-bg); border-bottom-left-radius: 4px; }
.msg.assistant p { margin: 0 0 8px 0; } .msg.assistant p:last-child { margin-bottom: 0; }
.msg.assistant pre { background: #0d1117; padding: 10px; border-radius: 6px; overflow-x: auto; margin: 8px 0; }
.msg.assistant code { font-family: "SF Mono", Consolas, monospace; font-size: 13px; }
.msg.assistant :not(pre) > code { background: #0d1117; padding: 2px 5px; border-radius: 3px; }
.msg.assistant ul, .msg.assistant ol { padding-left: 20px; margin: 4px 0; }
.msg.assistant blockquote { border-left: 3px solid var(--border); padding-left: 12px; color: var(--text-dim); margin: 4px 0; }
.msg.assistant h1,.msg.assistant h2,.msg.assistant h3 { margin: 8px 0 4px 0; }
.msg.assistant table { border-collapse: collapse; margin: 8px 0; }
.msg.assistant th,.msg.assistant td { border: 1px solid var(--border); padding: 4px 8px; font-size: 13px; }
.msg.error { align-self: center; color: var(--error); font-size: 12px; }
.msg.status { align-self: center; color: var(--text-dim); font-size: 12px; font-style: italic; }
.input-area { padding: 16px 20px; background: var(--surface); border-top: 1px solid var(--border); display: flex; gap: 10px; }
.input-area textarea { flex: 1; padding: 10px 14px; background: var(--bg); color: var(--text); border: 1px solid var(--border); border-radius: 8px; font-size: 14px; font-family: inherit; resize: none; outline: none; min-height: 44px; max-height: 120px; }
.input-area textarea:focus { border-color: var(--accent); }
.input-area button { padding: 10px 20px; background: var(--accent); color: #fff; border: none; border-radius: 8px; cursor: pointer; font-size: 14px; white-space: nowrap; }
.input-area button:disabled { opacity: 0.4; cursor: not-allowed; }

/* Modal (mkdir prompt) */
.modal-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.5); display: flex; align-items: center; justify-content: center; z-index: 200; }
.modal-box { background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: 20px; width: 280px; }
.modal-box h3 { font-size: 14px; margin-bottom: 12px; }
.modal-box input { width: 100%; padding: 8px 10px; background: var(--bg); color: var(--text); border: 1px solid var(--border); border-radius: 6px; font-size: 13px; outline: none; margin-bottom: 12px; }
.modal-box input:focus { border-color: var(--accent); }
.modal-box .modal-actions { display: flex; gap: 8px; justify-content: flex-end; }
.modal-box .modal-actions button { padding: 6px 14px; border-radius: 6px; font-size: 13px; cursor: pointer; border: none; }
.modal-box .modal-actions .btn-ok { background: var(--accent); color: #fff; }
.modal-box .modal-actions .btn-cancel { background: var(--border); color: var(--text); }

/* ── Task tab ── */
.panel-tabs { display: flex; border-bottom: 1px solid var(--border); }
.panel-tab { flex: 1; padding: 8px 0; background: none; border: none; color: var(--text-dim); font-size: 13px; cursor: pointer; border-bottom: 2px solid transparent; }
.panel-tab.active { color: var(--text); border-bottom-color: var(--accent); }
.panel-tab-content { display: flex; flex-direction: column; flex: 1; overflow: hidden; }

/* ── Task items ── */
.task-item { padding: 8px 12px; font-size: 13px; cursor: pointer; border-bottom: 1px solid var(--border); }
.task-item:hover { background: var(--hover); }
.task-item.success { opacity: 0.7; }
.task-short-id { color: var(--text-dim); font-size: 11px; }

/* ── Task card in chat ── */
.msg.task-card { background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: 10px 14px; margin: 6px 0; font-size: 13px; }
.msg.task-card.success { border-color: #22c55e44; }
.msg.task-card.failed { border-color: #ef444444; }
.task-card-icon { font-size: 16px; }
.task-card-error { color: var(--error); font-size: 12px; margin-top: 4px; }
.task-card-summary { color: var(--text-dim); font-size: 12px; margin-top: 4px; }

/* ── Session task icon ── */
.session-task-icon { margin-left: auto; font-size: 12px; flex-shrink: 0; }

/* ── Notification bar ── */
.notify-container { position: fixed; top: 8px; left: 50%; transform: translateX(-50%); z-index: 200; display: flex; flex-direction: column; gap: 6px; pointer-events: none; }
.task-notify-bar { pointer-events: auto; background: var(--surface); border: 1px solid var(--border); border-radius: 8px; padding: 8px 14px; font-size: 13px; display: flex; align-items: center; gap: 10px; opacity: 0; transition: opacity 0.3s; box-shadow: 0 4px 12px rgba(0,0,0,0.4); }
.task-notify-bar.show { opacity: 1; }
.task-notify-btn { background: var(--accent); color: #fff; border: none; border-radius: 4px; padding: 4px 10px; font-size: 12px; cursor: pointer; }