*{margin:0;padding:0;box-sizing:border-box}
body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.6}
.container{max-width:1140px;margin:0 auto;padding:0 20px}

.header{padding:16px 0;box-shadow:0 2px 10px rgba(0,0,0,0.06)}
.header .container{display:flex;justify-content:space-between;align-items:center}
.logo{font-size:24px;font-weight:700;text-decoration:none}
.nav a{margin-left:22px;text-decoration:none;font-size:15px}

.theme-circle{display:flex;gap:10px}
.circle{width:28px;height:28px;border-radius:50%;display:block}

.hero{padding:70px 0;text-align:center;border-radius:16px;margin:30px 0}
.hero h1{font-size:42px;margin-bottom:12px}
.hero p{font-size:17px;opacity:.9;margin-bottom:30px}
.btns{display:flex;gap:16px;justify-content:center;flex-wrap:wrap}
.btn{padding:13px 28px;border-radius:10px;text-decoration:none;font-weight:600}

.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin:40px 0}
.card{padding:28px;border-radius:16px;box-shadow:0 4px 14px rgba(0,0,0,0.05)}
.card h3{margin-bottom:10px}

@media(max-width:768px){
    .grid{grid-template-columns:1fr}
    .hero h1{font-size:28px}
    .nav a{margin-left:12px}
}

.box{max-width:440px;margin:60px auto;padding:36px;border-radius:18px;box-shadow:0 5px 18px rgba(0,0,0,0.06)}
.box h2{text-align:center;margin-bottom:24px}
input{width:100%;padding:14px;margin:10px 0;border:1px solid #e5e7eb;border-radius:10px}
button{width:100%;padding:14px;border:none;border-radius:10px;font-weight:600;cursor:pointer}

.item{padding:16px;border-bottom:1px solid #f3f4f6;margin-bottom:8px}