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

html,
body{
    width:100%;
    min-height:100%;
}

body{
    font-family:
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Arial,
    sans-serif;

    background:
    radial-gradient(
        circle at center,
        #353535 0%,
        #181818 65%,
        #0c0c0c 100%
    );

    color:white;

    overflow-x:hidden;
}


/* ==========================
   HEADER
========================== */

.reader-header{

    height:74px;

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

    padding:0 28px;

    background:
    rgba(20,20,20,.88);

    backdrop-filter:blur(15px);
    -webkit-backdrop-filter:blur(15px);

    border-bottom:
    1px solid rgba(255,255,255,.1);

    position:relative;
    z-index:100;
}


.reader-brand{

    display:flex;
    align-items:center;

    gap:16px;
}


.reader-brand img{

    height:48px;

    max-width:150px;

    object-fit:contain;
}


.reader-brand div{

    display:flex;
    flex-direction:column;

    gap:3px;
}


.reader-brand strong{

    font-size:15px;

    letter-spacing:.5px;
}


.reader-brand span{

    color:#aaa;

    font-size:12px;
}


.voltar{

    width:42px;
    height:42px;

    border-radius:50%;

    display:flex;
    align-items:center;
    justify-content:center;

    color:white;

    text-decoration:none;

    background:
    rgba(255,255,255,.08);

    transition:.25s;
}


.voltar:hover{

    background:
    rgba(255,255,255,.18);

    transform:translateX(-3px);
}


/* ==========================
   AÇÕES
========================== */

.reader-actions{

    display:flex;

    gap:10px;
}


.reader-actions button,
.reader-actions a{

    width:42px;
    height:42px;

    border:0;

    border-radius:50%;

    display:flex;
    align-items:center;
    justify-content:center;

    background:
    rgba(255,255,255,.08);

    color:white;

    font-size:16px;

    cursor:pointer;

    text-decoration:none;

    transition:.25s;
}


.reader-actions button:hover,
.reader-actions a:hover{

    background:
    rgba(255,255,255,.2);

    transform:translateY(-2px);
}


/* ==========================
   ÁREA PRINCIPAL
========================== */

.reader-area{

    min-height:
    calc(100vh - 140px);

    display:flex;

    align-items:center;
    justify-content:center;

    position:relative;

    padding:30px 80px;

    overflow:hidden;
}


/* ==========================
   LIVRO
========================== */

#book{

    margin:auto;

    filter:
    drop-shadow(
        0 25px 35px
        rgba(0,0,0,.65)
    );
}


.page{

    background:white;

    overflow:hidden;

    box-shadow:
    inset 0 0 20px
    rgba(0,0,0,.06);
}


.page canvas{

    display:block;

    width:100%;
    height:100%;

    object-fit:contain;
}


/* ==========================
   SOMBRA CENTRAL
========================== */

.stf__parent{

    margin:auto;
}


/* ==========================
   BOTÕES LATERAIS
========================== */

.nav-button{

    position:absolute;

    top:50%;

    transform:
    translateY(-50%);

    width:55px;
    height:55px;

    border:0;

    border-radius:50%;

    background:
    rgba(255,255,255,.1);

    backdrop-filter:blur(10px);

    color:white;

    font-size:20px;

    cursor:pointer;

    z-index:50;

    transition:.25s;
}


.nav-button:hover{

    background:
    rgba(255,255,255,.25);

    transform:
    translateY(-50%)
    scale(1.08);
}


.previous{

    left:20px;
}


.next{

    right:20px;
}


/* ==========================
   CONTROLES INFERIORES
========================== */

.reader-controls{

    height:66px;

    display:flex;

    align-items:center;
    justify-content:center;

    gap:25px;

    background:
    rgba(15,15,15,.9);

    border-top:
    1px solid
    rgba(255,255,255,.08);

    position:relative;

    z-index:100;
}


.reader-controls button{

    width:40px;
    height:40px;

    border:0;

    border-radius:50%;

    background:
    rgba(255,255,255,.1);

    color:white;

    cursor:pointer;

    transition:.25s;
}


.reader-controls button:hover{

    background:
    rgba(255,255,255,.22);
}


.page-indicator{

    font-size:13px;

    color:#aaa;

    min-width:130px;

    text-align:center;
}


.page-indicator span{

    color:white;

    font-weight:600;
}


/* ==========================
   LOADING
========================== */

#loading{

    position:absolute;

    top:50%;
    left:50%;

    transform:
    translate(-50%,-50%);

    text-align:center;

    z-index:200;
}


#loading p{

    margin-top:18px;

    color:#bbb;

    font-size:14px;
}


.spinner{

    width:45px;
    height:45px;

    border-radius:50%;

    border:
    4px solid
    rgba(255,255,255,.15);

    border-top-color:white;

    margin:auto;

    animation:
    spin .8s linear infinite;
}


@keyframes spin{

    to{
        transform:rotate(360deg);
    }

}


/* ==========================
   MOBILE
========================== */

@media(max-width:768px){

    .reader-header{

        height:65px;

        padding:0 12px;
    }


    .reader-brand img{

        height:38px;

        max-width:105px;
    }


    .reader-brand strong{

        display:none;
    }


    .reader-brand span{

        font-size:11px;
    }


    .reader-area{

        min-height:
        calc(100vh - 125px);

        padding:
        15px 5px;
    }


    .nav-button{

        display:none;
    }


    .reader-actions button,
    .reader-actions a{

        width:38px;
        height:38px;
    }


    .reader-controls{

        height:60px;
    }

}

/* =====================================================
   EFEITO REALISTA DA REVISTA
===================================================== */

#book {
    position: relative;

    margin: auto;

    filter:
        drop-shadow(
            0 30px 40px
            rgba(0,0,0,.55)
        );
}


/* PÁGINA */

#book .page {

    background: #fff;

    overflow: hidden;

    position: relative;

    border:
        1px solid
        rgba(0,0,0,.08);

}


/* CANVAS DO PDF */

#book .page canvas {

    display: block;

    width: 100%;

    height: 100%;

    object-fit: fill;

}


/* SOMBRA INTERNA DA FOLHA */

#book .page::after {

    content: "";

    position: absolute;

    inset: 0;

    pointer-events: none;

    box-shadow:
        inset 0 0 18px
        rgba(0,0,0,.08);

}


/* DEIXA A VIRADA MAIS NATURAL */

.stf__item {

    overflow: hidden;

}


/* SOMBRA DA REVISTA */

.stf__parent {

    perspective: 2000px;

}


/* MOBILE */

@media(max-width:768px){

    #book {

        width: 100%;

        max-width: 100%;

    }

}