body {
    margin: 0;
    font-family: "Segoe UI", sans-serif;
    background: #0a1633;
    color: #ffffff;

    /* smoother text rendering */
    -webkit-font-smoothing: antialiased;
}

/* TEXT SELECTION (when user highlights text) */
::selection {
    background: #ffffff;
    color: #0a1633;
}

/* CURSOR STYLE (caret in inputs) */
input, textarea {
    caret-color: #ffffff;  /* white blinking cursor */
}

/* NAVBAR */
.navbar {
    display: flex;
    justify-content: space-between;
    padding: 15px 30px;
    background: #10244b;
    box-shadow: 0 4px 12px rgba(0,0,0,0.6);
}

.navbar a {
    color: #ffffff;
    margin-left: 15px;
    text-decoration: none;
    font-weight: 500;
}

.navbar a:hover {
    color: #e8ebef;
}

/* HERO */
.hero {
    text-align: center;
    padding: 50px;
    background: linear-gradient(135deg, #1e3a8a, #8396bf);
    color: #ffffff;
}

/* GRID */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
    padding: 30px;
}

/* CARDS */
.card, .book-card {
    background: #2e4369;
    padding: 20px;
    border-radius: 15px;
    border: 1px solid #1e3a8a;
    color: #ffffff;
    transition: 0.3s;
}

.card:hover, .book-card:hover {
    transform: translateY(-6px);
    background: #1a2f5c;
    border-color: #60a5fa;
}

/* BUTTONS */
button {
    background: #2563eb;
    border: none;
    padding: 10px 15px;
    color: #ffffff;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: 0.3s;
}

button:hover {
    background: #1d4ed8;
}

/* INPUTS */
input {
    padding: 10px;
    margin: 5px;
    border-radius: 8px;
    border: 1px solid #1e3a8a;
    background: #0a1633;
    color: #ffffff;
    outline: none;
}

/* focus glow (important UX improvement) */
input:focus {
    border-color: #0d233d;
    box-shadow: 0 0 8px rgba(9, 46, 90, 0.5);
}

/* LOGIN BOX */
.auth-box {
    width: 320px;
    margin: 100px auto;
    padding: 25px;
    background: #12264a;
    border-radius: 15px;
    text-align: center;
    border: 1px solid #1e3a8a;
    color: #ffffff;
}