/* Estilos globales */
body {
    font-family: 'Poppins', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f2f5;
    color: #333;
}

/* Header */
header {
    background-color: #34495e;
    color: white;
    padding: 20px;
    text-align: center;
    position: relative;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1);
}

h1 {
    font-size: 2em;
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 2px;
    color: #ecf0f1;
}

.btn-back {
    position: absolute;
    top: 20px;
    left: 20px;
    background-color: #3498db;
    color: white;
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    font-size: 0.9em;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.btn-preview {
    background-color: #467fcf;
    color: white;
    padding: 12px;
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.3s ease;
    
  }
  .btn-preview:hover {
    background-color: #3a6fb0;
  }

.btn-back:hover {
    background-color: #2980b9;
    transform: translateY(-2px);
}

/* Main content */
main {
    padding: 40px 20px;
}

.file-list {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 20px;
}

.file-item {
    background-color: white;
    border-radius: 12px;
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
    padding: 20px;
    text-align: center;
    width: 220px;
    transition: transform 0.3s ease;
    position: relative;
}

.file-item:hover {
    transform: translateY(-5px);
}

.file-item h3 {
    font-size: 1.1em;
    color: #2c3e50;
    margin-bottom: 15px;
}

.file-item a {
    display: block;
    padding: 12px;
    background-color: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.file-item a:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}

.no-archivos {
    text-align: center;
    font-size: 1.2em;
    color: #7f8c8d;
    margin-top: 40px;
}

/* Footer */
footer {
    text-align: center;
    padding: 15px;
    background-color: #34495e;
    color: white;
    margin-top: 40px;
    box-shadow: 0 -4px 10px rgba(0, 0, 0, 0.1);
}

/* Search bar */
.search-bar {
    margin-bottom: 30px;
    text-align: center;
}

.search-bar input[type="text"], 
.search-bar input[type="date"] {
    padding: 12px;
    font-size: 1em;
    margin-right: 10px;
    border-radius: 30px;
    border: 1px solid #ccc;
    outline: none;
    transition: border 0.3s ease;
}

.search-bar input[type="text"]:focus, 
.search-bar input[type="date"]:focus {
    border-color: #3498db;
}

.search-bar button {
    padding: 12px 25px;
    font-size: 1em;
    background-color: #3498db;
    color: white;
    border: none;
    cursor: pointer;
    border-radius: 30px;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.search-bar button:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}

/* Button groups */
.button-group {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.btn-delete {
    background-color: #e74c3c;
    color: white;
    padding: 12px;
    width: 220px;
    border: none;
    border-radius: 30px;
    cursor: pointer;
    margin-top: 5px;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.btn-delete:hover {
    background-color: #c0392b;
    transform: translateY(-3px);
}

/* Download all button */
.btn-download-all {
    padding: 12px 25px;
    font-size: 1em;
    background-color: #3498db;
    color: white;
    border: none;
    cursor: pointer;
    border-radius: 30px;
    margin-left: 10px;
    transition: background-color 0.3s ease, transform 0.3s ease;
}

.btn-download-all:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
}

.search-download {
    display: flex;
    justify-content: center;
    gap: 10px;
}

/* Responsive Web Design */
@media (max-width: 768px) {
    header {
        padding: 15px;
    }

    h1 {
        font-size: 1.5em;
    }

    .file-item {
        width: 180px;
    }

    .btn-back {
        padding: 8px 15px;
        font-size: 0.8em;
    }

    .search-download {
        flex-direction: column;
        gap: 15px;
    }

    .search-bar input[type="text"],
    .search-bar input[type="date"],
    .search-bar button {
        width: 100%;
        margin-bottom: 10px;
    }
}

@media (max-width: 576px) {
    header {
        padding: 10px;
    }

    h1 {
        font-size: 1.2em;
    }

    .file-item {
        width: 100%;
    }

    .btn-back {
        padding: 5px 10px;
        font-size: 0.7em;
    }

    .btn-download-all {
        padding: 10px;
        font-size: 0.9em;
    }
}