:root {
    --bg: #0b1220;
    --bg-elev: #0f172a;
    --card: #0e1628;
    --border: #1f2a44;
    --text: #e5e7eb;

    --muted: #94a3b8;

    --primary: #22d3ee;

    --primary-weak: rgba(34, 211, 238, .12);
    --danger: #f87171;
    
    --shadow: 0 6px 18px rgba(0, 0, 0, .25);
}

* {
    box-sizing: border-box;
}

html,
body {
    height: 100%;
}

body {
    margin: 0;
    font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
    background: linear-gradient(180deg, var(--bg), var(--bg-elev));
    color: var(--text);
}

.container {
    width: min(1100px, 92%);
    margin: 0 auto;
    padding: 16px 0 28px;
}

header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(11, 18, 32, .7);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border);
}

header .container {
    padding: 14px 0;
}

header h1 {
    margin: 0 0 8px;
    font-size: 1.6rem;
}

nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

nav a {
    color: var(--text);
    text-decoration: none;
    padding: 6px 10px;
    border-radius: 10px;
    border: 1px solid transparent;
}

nav a:hover {
    border-color: var(--primary);
}


#search-form {
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
    margin: 18px auto 10px;
}

#search-input {
    flex: 1 1 520px;
    padding: 14px 16px;
    background: var(--card);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 14px;
    outline: none;
}

#search-input::placeholder {
    color: var(--muted);
}

button[type="submit"] {
    padding: 12px 18px;
    border-radius: 12px;
    border: 1px solid var(--primary);
    background: transparent;
    color: var(--text);
    cursor: pointer;
    transition: background .2s ease, transform .06s ease;
}

button[type="submit"]:hover {
    background: var(--primary-weak);
}

button[type="submit"]:active {
    transform: translateY(1px);
}

button[type="submit"]:disabled {
    opacity: .6;
    cursor: not-allowed;
}


#status {
    min-height: 22px;
    margin: 6px 0 8px;
    color: var(--primary);
    font-size: .95rem;
}

#status.error {
    color: var(--danger);
}

#results,
#fav-results {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 22px;
    margin-top: 14px;
}


.book-card {
    display: grid;
    grid-template-columns: 110px 1fr;
    gap: 14px;
    background: linear-gradient(180deg, #0c1426, #0e1628);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 14px;
    box-shadow: var(--shadow);
}

.book-card__img img {
    width: 110px;
    height: 155px;
    object-fit: cover;
    border-radius: 12px;
    background: #0a1122;
    display: block;
}

.book-card__info h3 {
    margin: 0 0 6px;
    font-size: 1.05rem;
    line-height: 1.2;
    color: var(--text);
}

.book-card__info p {
    margin: 0 0 10px;
    color: var(--muted);
    line-height: 1.5;
    font-size: .95rem;
}

.fav-btn,
.remove-fav {
    display: inline-block;
    margin-top: 6px;
    padding: 8px 12px;
    border-radius: 12px;
    border: 1px solid var(--primary);
    background: transparent;
    color: var(--text);
    cursor: pointer;
    transition: background .2s ease, transform .06s ease, border-color .2s ease;
}

.fav-btn:hover {
    background: var(--primary-weak);
}

.fav-btn:active {
    transform: translateY(1px);
}

.remove-fav {
    border-color: var(--danger);
}

.remove-fav:hover {
    background: rgba(248, 113, 113, .12);
}

#favorites {
    margin-top: 32px;
    padding: 18px 18px 26px;
    background: rgba(255, 255, 255, .03);
    border: 1px solid var(--border);
    border-radius: 18px;
}

#favorites h2 {
    margin: 0 0 10px;
    color: var(--primary);
    font-size: 1.2rem;
}


footer {
    border-top: 1px solid var(--border);
    color: var(--muted);
    text-align: center;
    padding: 26px 0 40px;
}


@media (max-width: 640px) {
    #search-input {
        flex-basis: 100%;
    }

    .book-card {
        grid-template-columns: 90px 1fr;
    }

    .book-card__img img {
        width: 90px;
        height: 130px;
    }
}


* {
    scrollbar-width: thin;
    scrollbar-color: #334155 #0b1220;
}

*::-webkit-scrollbar {
    height: 10px;
    width: 10px;
}

*::-webkit-scrollbar-thumb {
    background: #334155;
    border-radius: 10px;
}

*::-webkit-scrollbar-track {
    background: #0b1220;
}
header h1 {
    cursor: pointer;
}