/* Reset básico */
* {
  margin:0;
  padding:0;
  box‑sizing:border-box;
}
body, html {
  height:100%;
  font‑family:Arial, sans-serif;
}
body.dark {
  background‑color:#1e1e1e;
  color:#f0f0f0;
}
body.light {
  background‑color:#f9f9f9;
  color:#333;
}
.sidebar {
  position:fixed;
  top:0;
  left:0;
  width:240px;
  height:100%;
  background:#272727;
  color:#fff;
  display:flex;
  flex-direction:column;
  align-items:center;
  padding-top:20px;
}
.sidebar .logo‑container {
  text-align:center;
  margin-bottom:30px;
}
.sidebar .logo {
  width:80px;
  height:auto;
  margin-bottom:10px;
}
.sidebar nav ul {
  list-style:none;
  width:100%;
}
.sidebar nav ul li {
  width:100%;
}
.sidebar nav ul li button {
  width:100%;
  padding:12px 20px;
  background:transparent;
  border:none;
  color:inherit;
  text-align:left;
  font-size:16px;
  cursor:pointer;
}
.sidebar nav ul li button:hover {
  background:#383838;
}

.main {
  margin-left:240px;
  padding:20px;
  height:100%;
  display:flex;
  flex-direction:column;
}
.main‑header {
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-bottom:20px;
}
.cards {
  display:grid;
  grid-template-columns:repeat(auto‑fit, minmax(180px,1fr));
  gap:15px;
  margin-bottom:20px;
}
.card {
  background:#fff;
  padding:20px;
  border-radius:8px;
  text-align:center;
  font-size:18px;
  cursor:pointer;
  transition:transform .2s, box-shadow .2s;
}
body.dark .card {
  background:#2b2b2b;
}
.card:hover {
  transform:scale(1.03);
  box-shadow:0 4px 12px rgba(0,0,0,0.1);
}
.chat‑input {
  margin-bottom:20px;
  display:flex;
  flex:1;
  flex-direction:column;
}
.chat‑input textarea {
  width:100%;
  height:100px;
  padding:12px;
  font-size:16px;
  border:1px solid #ccc;
  border-radius:8px;
  resize:none;
}
body.dark .chat‑input textarea {
  background:#333;
  border:1px solid #555;
  color:#f0f0f0;
}
.chat‑input button {
  align-self:flex-end;
  margin-top:10px;
  padding:12px 24px;
  font-size:16px;
  border:none;
  border-radius:8px;
  background:#007bff;
  color:#fff;
  cursor:pointer;
}
.footer {
  margin-top:auto;
  padding:12px 0;
  text-align:center;
  border-top:1px solid #ccc;
}
body.dark .footer {
  border-top:1px solid #444;
}
.footer button {
  margin-left:10px;
  padding:6px 12px;
  font-size:14px;
  border:none;
  border-radius:4px;
  background:#28a745;
  color:#fff;
  cursor:pointer;
}