body{
margin:0;
font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto;
background:#EEF2F7;
display:flex;
justify-content:center;
}

.app{
width:100%;
max-width:420px;
background:#FFFFFF;
min-height:100vh;
padding:40px 24px;
box-sizing:border-box;
display:flex;
flex-direction:column;
}

/* Desktop refinement */
@media(min-width:768px){
body{
align-items:center;
justify-content:center;
min-height:100vh;
}
.app{
border-radius:20px;
min-height:600px;
box-shadow:0 20px 60px rgba(0,0,0,0.12);
justify-content:center;
}
}

/* Header */
.header{
display:flex;
align-items:center;
justify-content:center;
position:relative;
margin-bottom:30px;
}

.back{
position:absolute;
left:0;
font-size:20px;
cursor:pointer;
}

.logo img{
max-height:32px;
width:auto;
display:block;
}

/* Progress */
.progress{
width:100%;
height:10px;
background:#E5E7EB;
border-radius:10px;
overflow:hidden;
margin-bottom:50px;
}

.bar{
width:30%;
height:100%;
background:linear-gradient(90deg,#2563EB,#3B82F6);
}

/* Content */
.gif{
width:190px;
display:block;
margin:40px auto 30px;
}

h1{
font-size:22px;
text-align:center;
font-weight:700;
margin-bottom:16px;
}

p{
text-align:center;
color:#6B7280;
font-size:15px;
margin-bottom:40px;
}

/* Button */
.btn{
width:100%;
padding:18px;
border-radius:16px;
background:linear-gradient(90deg,#2563EB,#3B82F6);
color:#fff;
text-align:center;
font-weight:600;
text-decoration:none;
display:block;
box-shadow:0 15px 35px rgba(37,99,235,0.35);
transition:0.2s;
box-sizing:border-box;
margin-top:auto;
}

.btn:active{
transform:scale(0.96);
}