*{
margin:0;
padding:0;
box-sizing:border-box;
font-family:Arial,sans-serif;
}

body{
background:#111;
color:#fff;
}

.login-box{
width:350px;
margin:120px auto;
background:#1b1b1b;
padding:30px;
border-radius:12px;
}

.login-box h1{
text-align:center;
margin-bottom:20px;
color:#00e676;
}

.login-box input{
width:100%;
padding:12px;
margin-bottom:10px;
border:none;
border-radius:6px;
}

.login-box button{
width:100%;
padding:12px;
border:none;
background:#00e676;
font-weight:bold;
cursor:pointer;
}

.sidebar{
position:fixed;
width:240px;
height:100vh;
background:#181818;
padding:20px;
}

.sidebar h2{
color:#00e676;
margin-bottom:20px;
}

.sidebar ul{
list-style:none;
}

.sidebar li{
padding:12px 0;
}

.content{
margin-left:260px;
padding:25px;
}

.cards{
display:grid;
grid-template-columns:repeat(4,1fr);
gap:20px;
margin-top:20px;
}

.card{
background:#1d1d1d;
padding:20px;
border-radius:10px;
border-left:4px solid #00e676;
}

.card h3{
margin-bottom:10px;
}

@media(max-width:768px){

.content{
margin-left:0;
}

.sidebar{
display:none;
}

.cards{
grid-template-columns:1fr;
}
.topo{
padding:20px;
}

.cards{
display:grid;
grid-template-columns:repeat(4,1fr);
gap:20px;
margin:20px;
}

.card{
background:#1d1d1d;
padding:20px;
border-radius:12px;
text-align:center;
}

.treino-box{
background:#1d1d1d;
padding:20px;
margin:20px;
border-radius:12px;
}

.timer{
background:#1d1d1d;
padding:20px;
margin:20px;
text-align:center;
border-radius:12px;
}

#contador{
font-size:60px;
font-weight:bold;
color:#00e676;
}

@media(max-width:768px){

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

}

.btn-outline-light{
    border-radius:10px;
    font-weight:600;
}

.btn-success{
    border-radius:10px;
    font-weight:600;
}

}