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

body{
    font-family:Arial, Helvetica, sans-serif;
    background:#f5f5f5;
    color:#222;
    transition:.3s;
}

header{
    background:#1f2937;
    color:white;
    position:sticky;
    top:0;
}

nav{
    max-width:1100px;
    margin:auto;
    display:flex;
    justify-content:space-between;
    align-items:center;
    padding:15px;
}

nav ul{
    display:flex;
    list-style:none;
    gap:20px;
}

nav a{
    color:white;
    text-decoration:none;
}

#themeBtn{
    padding:8px 12px;
    cursor:pointer;
    border:none;
    border-radius:5px;
}

.hero{
    text-align:center;
    padding:120px 20px;
    background:linear-gradient(135deg,#2563eb,#4f46e5);
    color:white;
}

.hero span{
    color:#ffd166;
}

.btn{
    display:inline-block;
    margin-top:20px;
    padding:12px 25px;
    background:white;
    color:#2563eb;
    text-decoration:none;
    border-radius:6px;
    font-weight:bold;
}

section{
    max-width:1000px;
    margin:auto;
    padding:70px 20px;
}

h2{
    margin-bottom:20px;
}

.cards{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(120px,1fr));
    gap:20px;
}

.card{
    background:white;
    padding:20px;
    text-align:center;
    border-radius:10px;
    box-shadow:0 3px 8px rgba(0,0,0,.1);
}

.project{
    background:white;
    margin:20px 0;
    padding:20px;
    border-radius:10px;
}

.timeline div{
    background:white;
    padding:20px;
    border-left:5px solid royalblue;
    border-radius:5px;
}

footer{
    text-align:center;
    padding:20px;
    background:#1f2937;
    color:white;
}

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

.dark .card,
.dark .project,
.dark .timeline div{
    background:#1f2937;
}

.dark .btn{
    background:#2563eb;
    color:white;
}

@media(max-width:700px){

nav{
    flex-direction:column;
    gap:15px;
}

nav ul{
    flex-wrap:wrap;
    justify-content:center;
}

.hero{
    padding:80px 20px;
}

}