:root{
  --bg:#131022; --bg2:#1a1530; --panel:#1e1938; --border:#2d2650;
  --text:#ece9f7; --muted:#9a90c4; --accent:#7c6cf0; --accent2:#a78bfa;
  --user:#2b2350; --shadow:0 10px 30px rgba(0,0,0,.35);
}
[data-theme="light"]{
  --bg:#f7f6fc; --bg2:#ffffff; --panel:#ffffff; --border:#e4e0f2;
  --text:#221c3d; --muted:#6f689a; --accent:#6c5ce7; --accent2:#8b5cf6;
  --user:#ece9fd; --shadow:0 10px 30px rgba(60,50,120,.12);
}
*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%}
body{font-family:"Segoe UI",Inter,system-ui,sans-serif;background:var(--bg);color:var(--text)}
.app{display:flex;height:100vh}

/* ---------- Sidebar ---------- */
.sidebar{width:264px;background:var(--bg2);border-right:1px solid var(--border);
  display:flex;flex-direction:column;padding:14px 12px;gap:10px}
.brand{display:flex;align-items:center;gap:10px;font-size:19px;font-weight:700;padding:4px 6px}
.logo{width:30px;height:30px;border-radius:50%;
  background:radial-gradient(circle at 65% 35%, #c4b5fd 0%, #7c6cf0 45%, #1e1538 100%);
  box-shadow:0 0 14px rgba(124,108,240,.6)}
#themeBtn{margin-left:auto;background:none;border:1px solid var(--border);color:var(--text);
  width:32px;height:32px;border-radius:8px;cursor:pointer;font-size:15px}
#themeBtn:hover{background:var(--panel)}
.new-chat{display:block;text-align:center;text-decoration:none;color:#fff;font-weight:600;
  background:linear-gradient(135deg,var(--accent),var(--accent2));padding:11px;border-radius:12px}
.new-chat:hover{filter:brightness(1.1)}
.chat-list{flex:1;overflow-y:auto;display:flex;flex-direction:column;gap:4px}
.chat-row{display:flex;align-items:center;border-radius:10px}
.chat-row:hover,.chat-row.active{background:var(--panel)}
.chat-item{flex:1;padding:9px 10px;color:var(--text);text-decoration:none;font-size:14px;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chat-del{padding:0 9px;color:var(--muted);text-decoration:none;font-size:12px;opacity:0}
.chat-row:hover .chat-del{opacity:1}
.chat-del:hover{color:#ff6b81}
.side-foot{font-size:11px;color:var(--muted);text-align:center;line-height:1.6;border-top:1px solid var(--border);padding-top:10px}

/* ---------- Main ---------- */
.main{flex:1;display:flex;flex-direction:column;background:var(--bg)}
.topbar{display:flex;justify-content:center;padding:12px}
.model-pill{font-size:12px;color:var(--muted);border:1px solid var(--border);
  border-radius:999px;padding:5px 14px;background:var(--bg2)}
.chat{flex:1;overflow-y:auto;padding:10px 0 20px}

.msg{display:flex;gap:14px;max-width:820px;margin:0 auto;padding:16px 24px}
.avatar{width:34px;height:34px;border-radius:50%;flex-shrink:0;display:flex;align-items:center;
  justify-content:center;font-weight:700;font-size:14px}
.msg.ai .avatar{background:radial-gradient(circle at 65% 35%, #c4b5fd, #7c6cf0 60%, #1e1538)}
.msg.user .avatar{background:var(--user);border:1px solid var(--border)}
.bubble{line-height:1.7;font-size:15px;word-break:break-word}
.msg.ai .bubble{padding-top:4px}
.msg.user .bubble{background:var(--user);border:1px solid var(--border);
  padding:10px 16px;border-radius:16px;border-top-left-radius:4px}
.bubble pre{background:#0e0b1c;border:1px solid var(--border);border-radius:10px;
  padding:12px;overflow-x:auto;margin:10px 0}
[data-theme="light"] .bubble pre{background:#f0eefb}
.bubble code{font-family:Consolas,Menlo,monospace;font-size:13px}
.bubble p code{background:var(--panel);border:1px solid var(--border);padding:1px 6px;border-radius:6px}
.bubble pre code{background:none;padding:0}
.cursor{display:inline-block;width:8px;height:16px;background:var(--accent);
  vertical-align:-2px;animation:blink 1s steps(1) infinite;border-radius:2px}
@keyframes blink{50%{opacity:0}}

.empty{margin:auto;text-align:center;color:var(--muted);padding:40px}
.empty .logo{width:64px;height:64px;margin:0 auto 18px}
.empty h1{font-size:26px;color:var(--text);margin-bottom:8px}
.suggest{display:flex;gap:10px;justify-content:center;flex-wrap:wrap;margin-top:22px}
.suggest button{background:var(--bg2);border:1px solid var(--border);color:var(--text);
  padding:9px 16px;border-radius:999px;cursor:pointer;font-size:13px}
.suggest button:hover{border-color:var(--accent)}

/* ---------- Composer ---------- */
.composer{max-width:820px;width:calc(100% - 48px);margin:0 auto 6px;display:flex;gap:10px;
  align-items:flex-end;background:var(--bg2);border:1px solid var(--border);
  border-radius:20px;padding:10px 10px 10px 18px;box-shadow:var(--shadow)}
.composer:focus-within{border-color:var(--accent)}
#input{flex:1;background:none;border:none;outline:none;color:var(--text);
  font-size:15px;resize:none;max-height:160px;font-family:inherit;line-height:1.5}
#send{width:40px;height:40px;border-radius:12px;border:none;cursor:pointer;font-size:16px;color:#fff;
  background:linear-gradient(135deg,var(--accent),var(--accent2))}
#send:disabled{opacity:.5;cursor:default}
.disclaimer{text-align:center;font-size:11px;color:var(--muted);padding:6px 0 12px}

/* ---------- Responsive ---------- */
@media(max-width:760px){
  .sidebar{display:none}
  .msg{padding:14px 16px}
}

/* ---------- Ejecutor Python ---------- */
.bubble pre{position:relative}
.run-btn{position:absolute;top:8px;right:8px;background:var(--accent);color:#fff;border:none;
  padding:4px 11px;border-radius:8px;font-size:12px;cursor:pointer;opacity:.9;font-family:inherit}
.run-btn:hover{opacity:1}
.run-btn:disabled{opacity:.55;cursor:default}
.run-output{background:#0e0b1c;border:1px solid var(--border);border-left:3px solid var(--accent);
  border-radius:8px;padding:10px 12px;margin:8px 0;font-size:13px;white-space:pre-wrap;
  font-family:Consolas,Menlo,monospace}
.run-output.err{border-left-color:#ff6b81;color:#ff9aa8}
[data-theme="light"] .run-output{background:#f0eefb}
[data-theme="light"] .run-output.err{color:#c0392b}