:root{
  --bg:#0f172a;
  --bg2:#111827;
  --card:#ffffff;
  --primary:#6366f1;
  --primary2:#8b5cf6;
  --text:#0f172a;
  --muted:#64748b;
  --border:#e2e8f0;
  --shadow:0 10px 35px rgba(0,0,0,.12);
  --radius:22px;
}

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

html{
  scroll-behavior:smooth;
}

body{
  font-family:"Inter",sans-serif;
  background:
  radial-gradient(circle at top left,#4f46e5 0%,transparent 28%),
  radial-gradient(circle at bottom right,#9333ea 0%,transparent 28%),
  linear-gradient(135deg,#0f172a,#111827,#1e293b);
  min-height:100vh;
  color:white;
  overflow-x:hidden;
}

/* HEADER */

header{
  width:100%;
  padding:20px 40px;
  position:sticky;
  top:0;
  z-index:999;
  backdrop-filter:blur(14px);
  background:rgba(15,23,42,.65);
  border-bottom:1px solid rgba(255,255,255,.08);

  display:flex;
  align-items:center;
  justify-content:space-between;
}

.brand{
  display:flex;
  align-items:center;
  gap:15px;
}

.logo{
  width:52px;
  height:52px;
  border-radius:18px;
  background:linear-gradient(135deg,#6366f1,#8b5cf6,#ec4899);
  box-shadow:
  0 0 20px rgba(99,102,241,.6),
  0 0 45px rgba(139,92,246,.4);
}

.brand h1{
  font-size:22px;
  font-weight:800;
  letter-spacing:.5px;
}

.brand p{
  color:#cbd5e1;
  font-size:13px;
  margin-top:3px;
}

.top-btn{
  border:none;
  padding:12px 20px;
  border-radius:14px;
  background:linear-gradient(135deg,#6366f1,#8b5cf6);
  color:white;
  font-weight:600;
  cursor:pointer;
  transition:.25s;
  box-shadow:0 10px 25px rgba(99,102,241,.35);
}

.top-btn:hover{
  transform:translateY(-2px) scale(1.03);
}

/* LAYOUT */

.layout{
  width:min(1400px,94%);
  margin:30px auto;
  display:grid;
  grid-template-columns:280px 1fr;
  gap:28px;
}

/* SIDEBAR */

.sidebar{
  background:rgba(255,255,255,.08);
  border:1px solid rgba(255,255,255,.08);
  backdrop-filter:blur(14px);
  padding:25px;
  border-radius:28px;
  position:sticky;
  top:105px;
  height:max-content;
  box-shadow:var(--shadow);
}

.sidebar h3{
  font-size:14px;
  letter-spacing:2px;
  margin-bottom:20px;
  color:#cbd5e1;
}

.sidebar ul{
  list-style:none;
}

.sidebar li{
  padding:14px 16px;
  margin-bottom:10px;
  border-radius:14px;
  cursor:pointer;
  transition:.25s;
  font-size:14px;
  font-weight:600;
  color:#e2e8f0;
  background:rgba(255,255,255,.03);
}

.sidebar li:hover{
  background:linear-gradient(135deg,#6366f1,#8b5cf6);
  transform:translateX(5px);
}

/* CONTENT */

.content-area{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(340px,1fr));
  gap:24px;
}

.activity{
  display:none;
  position:relative;
  overflow:hidden;
  background:rgba(255,255,255,.95);
  color:var(--text);
  border-radius:30px;
  padding:28px;
  box-shadow:var(--shadow);
  animation:show .35s ease;
}

.activity.visible{
  display:block;
}

@keyframes show{
  from{
    opacity:0;
    transform:translateY(20px) scale(.96);
  }
  to{
    opacity:1;
    transform:translateY(0) scale(1);
  }
}

.activity h3{
  font-size:22px;
  margin-bottom:18px;
  font-weight:800;
}

.card{
  padding:18px;
  border-radius:18px;
  background:#f8fafc;
  margin-bottom:16px;
  line-height:1.6;
  color:#334155;
}

/* INPUTS */

input{
  width:100%;
  padding:14px 16px;
  border:none;
  outline:none;
  border-radius:16px;
  margin-top:12px;
  background:#f8fafc;
  border:1px solid #dbeafe;
  font-size:15px;
  transition:.2s;
}

input:focus{
  border-color:#6366f1;
  box-shadow:0 0 0 4px rgba(99,102,241,.15);
}

/* BUTTONS */

button{
  border:none;
  padding:13px 18px;
  margin-top:14px;
  border-radius:16px;
  cursor:pointer;
  font-size:14px;
  font-weight:700;
  color:white;
  background:linear-gradient(135deg,#6366f1,#8b5cf6);
  transition:.25s;
  box-shadow:0 12px 25px rgba(99,102,241,.25);
}

button:hover{
  transform:translateY(-2px);
}

.row{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
}

ul{
  list-style:none;
  margin-top:12px;
}

li{
  margin-bottom:10px;
  padding:12px 14px;
  border-radius:12px;
  background:#f8fafc;
  color:#334155;
}

p{
  margin-top:12px;
  line-height:1.6;
}

#myImage{
  width:100%;
  border-radius:20px;
  margin-top:10px;
}

footer{
  text-align:center;
  padding:30px;
  color:#cbd5e1;
  font-size:14px;
}

/* MOBILE */

@media(max-width:950px){

  header{
    padding:18px;
  }

  .layout{
    grid-template-columns:1fr;
  }

  .sidebar{
    position:relative;
    top:0;
  }

  .content-area{
    grid-template-columns:1fr;
  }

}
.dark{
  background: #0b1020;
  color: #e5e7eb;
}

.dark .activity{
  background: #111827;
  color: white;
}

.dark input{
  background: #1f2937;
  color: white;
  border: 1px solid #374151;
}

.dark button{
  filter: brightness(1.1);
}