.bc-grid{
    display:grid;
    gap:30px;
    grid-template-columns:1fr;
}

.bc-card{
    width:100%;
    max-width:var(--bc-max-width,750px);
    margin:0 auto;
    background:transparent;
}

.bc-content{
    padding:0;
}

.bc-title{
    margin:0 0 14px;
    text-align:center;
    font-size:clamp(20px,3vw,28px);
    line-height:1.25;
}

.bc-description{
    margin:0 auto 16px;
    color:#4b5563;
    text-align:center;
}

.bc-actions{
    display:flex;
    align-items:stretch;
    justify-content:center;
    gap:12px;
    width:100%;
    margin:0 0 16px;
}

.bc-button{
    display:inline-flex;
    flex:1 1 0;
    min-height:50px;
    align-items:center;
    justify-content:center;
    gap:9px;
    padding:12px 18px;
    border:0;
    border-radius:9px;
    color:#fff!important;
    font:inherit;
    font-weight:700;
    line-height:1.2;
    text-align:center;
    text-decoration:none!important;
    cursor:pointer;
    transition:filter .18s ease,transform .18s ease;
}

.bc-open{
    background:#249ca5;
}

.bc-download{
    background:#f08a17;
}

.bc-button:hover,
.bc-button:focus{
    color:#fff!important;
    filter:brightness(.93);
    transform:translateY(-1px);
}

.bc-icon{
    flex:0 0 auto;
    font-size:19px;
    line-height:1;
}

.bc-preview{
    display:flex;
    width:100%;
    align-items:flex-start;
    justify-content:center;
    overflow:hidden;
    border-radius:10px;
    background:transparent;
}

.bc-cover{
    display:block;
    width:100%;
    height:auto!important;
    max-width:100%;
    max-height:none!important;
    object-fit:contain;
    border-radius:10px;
    box-shadow:0 5px 20px rgba(0,0,0,.10);
}

.bc-placeholder{
    display:grid;
    width:100%;
    min-height:420px;
    place-items:center;
    border-radius:10px;
    background:#eef1f4;
    color:#6b7280;
    font-size:40px;
    font-weight:800;
}

.bc-viewer{
    width:100%;
    height:min(var(--bc-height),82vh);
    min-height:500px;
    overflow:hidden;
    border:1px solid rgba(0,0,0,.12);
    border-radius:10px;
    background:#f3f4f6;
    box-shadow:0 5px 20px rgba(0,0,0,.08);
}

.bc-viewer iframe{
    width:100%;
    height:100%;
    border:0;
}

@media(min-width:640px){
    .bc-cols-2{
        grid-template-columns:repeat(2,minmax(0,1fr));
    }

    .bc-cols-3{
        grid-template-columns:repeat(3,minmax(0,1fr));
    }

    .bc-cols-4{
        grid-template-columns:repeat(4,minmax(0,1fr));
    }

    .bc-cols-2 .bc-card,
    .bc-cols-3 .bc-card,
    .bc-cols-4 .bc-card{
        max-width:100%;
    }
}

@media(max-width:767px){
    .bc-card{
        max-width:100%;
    }

    .bc-actions{
        gap:8px;
    }

    .bc-button{
        min-height:48px;
        padding:11px 10px;
        font-size:14px;
    }

    .bc-viewer{
        height:72vh;
        min-height:480px;
    }
}

@media(max-width:480px){
    .bc-actions{
        flex-direction:column;
    }

    .bc-button{
        width:100%;
    }
}

@media(prefers-reduced-motion:reduce){
    .bc-button{
        transition:none;
    }
}