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

body {
    background: url("books.jpg") no-repeat center center fixed;
    background-size: cover;
    font-family: Arial, sans-serif;
    color: white;
}

.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.4);
    backdrop-filter: blur(4px);
    z-index: -1;
}


header {
    display: flex;
    justify-content: space-between;
    padding: 20px 60px;
    align-items: center;
}

.logo h1 { font-size: 32px; }
.logo h3 { font-size: 16px; opacity: 0.8; }


nav ul {
    display: flex;
    list-style: none;
    gap: 25px;
}

nav a {
    color: white;
    text-decoration: none;
    font-size: 18px;
}

nav a.active,
nav a:hover {
    border-bottom: 2px solid #fff;
}


main {
    margin-top: 30px;
    padding: 40px 60px;
}

.section { display: none; }
.section.visible { display: block; }


.form-card {
    width: 420px;
    padding: 20px;
    background: rgba(255,255,255,0.12);
    border-radius: 10px;
    backdrop-filter: blur(6px);
}

.form-row {
    margin-bottom: 12px;
}

.form-row label {
    font-size: 14px;
    display: block;
    margin-bottom: 3px;
}

.form-row input,
.form-row select {
    width: 100%;
    padding: 7px;
    border-radius: 6px;
    border: none;
}


.btn {
    display: inline-block;
    padding: 10px 18px;
    background: #007bff;
    text-align: center;
    color: white;
    border-radius: 6px;
    text-decoration: none;
}

.btn:hover {
    background: #0059c9;
}


.toast {
    position: fixed;
    bottom: 25px;
    right: 25px;
    background: #28a745;
    padding: 10px 15px;
    border-radius: 6px;
}