body {
    /*background: linear-gradient(135deg, #1a2a6c, #b21f1f, #fdbb2d);*/
    /*background-attachment: fixed;*/

    /*background: #2c3e50; !* fallback for old browsers *!*/
    /*background: -webkit-linear-gradient(to right, #2c3e50, #4ca1af); !* Chrome 10-25, Safari 5.1-6 *!*/
    /*background: linear-gradient(to right, #2c3e50, #4ca1af); !* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ *!*/

    background: #2c3e50; /* fallback for old browsers */
    background: -webkit-linear-gradient(to right, #19547b, #ffd89b); /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(to right, #19547b, #ffd89b); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */

    /* A bit more sublte: */
    background: #2c3e50; /* fallback for old browsers */
    background: -webkit-linear-gradient(to right, #2c3e50, #4a6b8a); /* Chrome 10-25, Safari 5.1-6 */
    background: linear-gradient(to right, #2c3e50, #4a6b8a); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */

    color: #fff;
    min-height: 100vh;
}

.container {
    max-width: 1200px;
}

h1, h2 {
    color: #fff;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.btn-primary {
    background-color: rgba(255, 255, 255, 0.2);
    border-color: transparent;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.btn-primary:hover {
    background-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.form-control {
    background-color: rgba(255, 255, 255, 0.1);
    border: none;
    color: #fff;
    backdrop-filter: blur(10px);
}

.form-control::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.form-control:focus {
    background-color: rgba(255, 255, 255, 0.2);
    box-shadow: 0 0 0 0.2rem rgba(255, 255, 255, 0.25);
}

.card {
    background-color: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-5px) scale(1.02);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.2);
}

.card-title {
    color: #fff;
    font-weight: bold;
}

.card-text {
    color: rgba(255, 255, 255, 0.8);
}

.text-muted {
    color: rgba(255, 255, 255, 0.6) !important;
}

.list-group-item {
    background-color: rgba(255, 255, 255, 0.05);
    border: none;
    color: #fff;
    transition: all 0.3s ease;
}

.list-group-item:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

.preview-toggle {
    cursor: pointer;
    transition: all 0.3s ease;
}

.preview-toggle:hover {
    color: #fdbb2d;
}

.preview-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.5s ease-out;
}

.preview-content.show {
    max-height: 500px;
}


.card-1 .card-title {
    color: #64ffda;
}

.card-2 .card-title {
    color: #ff9e64;
}

.card-3 .card-title {
    color: #bd93f9;
}

.card-4 .card-title {
    color: #50fa7b;
}

.card-1, .card-2, .card-3, .card-4 {
    border-left: 3px solid rgba(255, 255, 255, 0.2);
}

.card-1:hover {
    border-left-color: #64ffda;
}

.card-2:hover {
    border-left-color: #ff9e64;
}

.card-3:hover {
    border-left-color: #bd93f9;
}

.card-4:hover {
    border-left-color: #50fa7b;
}

.preview-toggle {
    background: rgba(255, 255, 255, 0.1);
    padding: 5px 10px;
    border-radius: 4px;
    display: inline-block;
}