:root{--bg: #1e1e1e;--surface: #252526;--border: #3c3c3c;--text: #cccccc;--accent: #0078d4;--accent-hover: #1a8fff;--tab-active: #1e1e1e;--tab-inactive: #2d2d2d;--sidebar-width: 220px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;background:var(--bg);color:var(--text);height:100vh;overflow:hidden}#app{display:flex;flex-direction:column;height:100vh}header{padding:12px 20px;border-bottom:1px solid var(--border);display:flex;align-items:baseline;gap:16px}header h1{font-size:18px;font-weight:600;color:#fff}header .subtitle{font-size:13px;color:#888}#language-tabs{display:flex;background:var(--tab-inactive);border-bottom:1px solid var(--border);padding:0 8px;gap:2px}.tab{padding:8px 20px;border:none;background:transparent;color:#999;cursor:pointer;font-size:13px;font-family:inherit;border-bottom:2px solid transparent;transition:all .15s}.tab:hover{color:#ddd;background:#ffffff0a}.tab.active{color:#fff;background:var(--tab-active);border-bottom-color:var(--accent)}#workspace{flex:1;display:flex;overflow:hidden}#editor-container{flex:1;overflow:hidden}#sidebar{width:var(--sidebar-width);min-width:var(--sidebar-width);background:var(--surface);border-right:1px solid var(--border);display:flex;flex-direction:column;overflow:hidden}.sidebar-tabs{display:flex;border-bottom:1px solid var(--border)}.sidebar-tab{flex:1;padding:6px 8px;border:none;background:transparent;color:#888;cursor:pointer;font-size:11px;font-family:inherit;text-transform:uppercase;letter-spacing:.5px;border-bottom:2px solid transparent;transition:all .15s}.sidebar-tab:hover{color:#ccc}.sidebar-tab.active{color:#fff;border-bottom-color:var(--accent)}.sidebar-panel{display:none;flex:1;overflow-y:auto}.sidebar-panel.active{display:block}.badge{display:inline-block;min-width:16px;height:16px;padding:0 4px;border-radius:8px;background:#f14c4c;color:#fff;font-size:10px;font-weight:600;line-height:16px;text-align:center}.badge.hidden{display:none}.file-item{padding:4px 12px;cursor:pointer;font-size:13px;display:flex;align-items:center;gap:6px;color:var(--text);transition:background .1s}.file-item:hover{background:#ffffff0f}.file-item.active{background:#0078d433;color:#fff}.file-item .file-icon{font-size:14px;opacity:.7}.diag-group-header{padding:4px 12px;font-size:11px;font-weight:600;color:#888;text-transform:uppercase;letter-spacing:.4px;border-bottom:1px solid var(--border);background:#00000026}.diag-item{padding:4px 12px;cursor:pointer;font-size:12px;line-height:1.4;transition:background .1s;border-bottom:1px solid rgba(255,255,255,.03)}.diag-item:hover{background:#ffffff0f}.diag-item .diag-message{color:var(--text)}.diag-item .diag-location{color:#666;font-size:11px;margin-top:1px}.diag-item.sev-error .diag-message{color:#f14c4c}.diag-item.sev-warning .diag-message{color:#cca700}.diag-item.sev-info .diag-message{color:#3794ff}.diag-item.sev-hint .diag-message{color:#888}.diag-empty{padding:16px 12px;font-size:12px;color:#666;text-align:center}footer{padding:4px 16px;border-top:1px solid var(--border);background:var(--surface);font-size:12px;display:flex;align-items:center;gap:12px}#status{color:#888}#status.connected{color:#4ec9b0}#status.error{color:#f44747}#status-diagnostics{margin-left:auto;font-size:12px;color:#888}#status-diagnostics.error{color:#f14c4c}#status-diagnostics.warning{color:#cca700}#toast-container{position:fixed;top:12px;right:12px;z-index:10000;display:flex;flex-direction:column;gap:8px;pointer-events:none}.toast{display:flex;align-items:flex-start;gap:8px;min-width:280px;max-width:420px;padding:10px 14px;border-radius:4px;background:#252526;border:1px solid var(--border);box-shadow:0 4px 16px #00000080;font-size:13px;color:var(--text);opacity:0;transform:translate(100%);transition:opacity .2s,transform .3s ease-out;pointer-events:auto}.toast-visible{opacity:1;transform:translate(0)}.toast-info{border-left:3px solid #3794ff}.toast-warning{border-left:3px solid #cca700}.toast-error{border-left:3px solid #f14c4c}.toast-icon{flex-shrink:0;width:16px;height:16px;margin-top:1px}.toast-body{flex:1;min-width:0}.toast-message{word-break:break-word}.toast-actions{display:flex;gap:8px;margin-top:6px}.toast-action{padding:2px 8px;border:1px solid var(--accent);border-radius:2px;background:transparent;color:var(--accent);font-size:12px;cursor:pointer;font-family:inherit}.toast-action:hover{background:#0078d426}.toast-close{flex-shrink:0;width:20px;height:20px;border:none;background:transparent;color:#888;cursor:pointer;font-size:16px;line-height:20px;text-align:center;border-radius:2px}.toast-close:hover{color:#fff;background:#ffffff1a}