@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;700&family=Playfair+Display:wght@400;700&display=swap');

:root {
    --primary-color: #333;
    --secondary-color: #f5f5f5;
    --text-color: #333;
    --background-color: #f5f5f5;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --hover-color: #666;
    --transition-speed: 0.3s;
}

.dark-theme {
    --primary-color: #f5f5f5;
    --secondary-color: #333;
    --text-color: #f5f5f5;
    --background-color: #222;
    --shadow-color: rgba(255, 255, 255, 0.1);
    --hover-color: #ddd;
}

html {
    scroll-behavior: smooth;
    font-family: 'Montserrat', sans-serif;
    margin: 0;
    padding: 0;
    overflow-x: hidden;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--primary-color);
    color: var(--secondary-color);
    padding: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 100;
    box-shadow: 0 2px 5px var(--shadow-color);
}

.menu-btn {
    background-color: transparent;
    border: none;
    cursor: pointer;
    width: 40px;
    height: 40px;
    position: fixed;
    top: 8px;
    right: 25px;
    border-radius: 50%;
    z-index: 102;
    transition: transform var(--transition-speed);
}

.menu-btn:hover {
    transform: scale(1.1);
}

.menu-icon {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 32px;
    height: 32px;
}

.search-bar {
    display: flex;
    align-items: center;
    background-color: var(--secondary-color);
    border-radius: 20px;
    padding: 8px 16px;
    box-shadow: 0 2px 5px var(--shadow-color);
    transition: box-shadow var(--transition-speed);
    margin-right: 60px;
}

.search-bar.active {
    box-shadow: 0 4px 10px var(--shadow-color);
}

.search-input {
    flex: 1;
    border: none;
    background-color: transparent;
    font-size: 16px;
    outline: none;
    padding: 0;
    color: var(--text-color);
}

.search-input::placeholder {
    color: #999;
}

.search-btn {
    background-color: transparent;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: transform var(--transition-speed);
}

.search-btn:hover {
    transform: scale(1.1);
}

.search-btn svg {
    width: 20px;
    height: 20px;
    stroke: var(--text-color);
    transition: stroke var(--transition-speed);
}

.search-btn:hover svg {
    stroke: var(--hover-color);
}

main {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: calc(100vh - 120px);
    padding: 20px;
    margin-top: 60px;
}

.book-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    grid-gap: 20px;
    padding: 20px;
    width: 100%;
    max-width: 1200px;
}

.grid-item {
    position: relative;
    background-color: var(--secondary-color);
    border-radius: 10px;
    box-shadow: 0 2px 5px var(--shadow-color);
    cursor: pointer;
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
    overflow: hidden;
}

.grid-item img {
    width: 100%;
    height: auto;
    border-radius: 10px;
    transition: transform var(--transition-speed);
}

.grid-item:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 10px var(--shadow-color);
}

.grid-item:hover img {
    transform: scale(1.1);
}

.textElement {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    padding: 5px;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    font-family: 'Playfair Display';
    font-size: 15px;
    text-align: center;
    opacity: 0.8;
    transition: opacity var(--transition-speed);
}

.grid-item:hover .textElement {
    opacity: 1;
}

.panel {
    position: fixed;
    top: 0;
    right: -100%;
    background-color: var(--background-color);
    height: 100vh;
    width: 50%;
    padding: 20px;
    transition: right var(--transition-speed);
    box-shadow: -2px 0 5px var(--shadow-color);
    z-index: 101;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.panel h3 {
    margin: 0 0 20px;
    font-size: 24px;
    font-weight: bold;
    color: var(--text-color);
}

.panel ul {
    list-style-type: none;
    padding: 0;
    width: 100%;
}

.panel li {
    margin-bottom: 15px;
}

.panel a {
    color: var(--text-color);
    text-decoration: none;
    font-size: 18px;
    transition: color var(--transition-speed), background-color var(--transition-speed);
    display: block;
    padding: 10px;
    border-radius: 5px;
    background-color: var(--secondary-color);
    box-shadow: 0 2px 5px var(--shadow-color);
}

.panel a:hover {
    color: var(--hover-color);
    background-color: var(--primary-color);
}

.panel.active {
    right: 0;
}

.loading-spinner {
    display: none;
}

.loading-spinner.active {
    display: block;
}

.error-message {
    position: fixed;
    bottom: 10px;
    left: 50%;
    transform: translateX(-50%);
    background-color: #ff4d4d;
    color: white;
    padding: 10px;
    border-radius: 5px;
    box-shadow: 0 2px 5px var(--shadow-color);
    z-index: 200;
    display: none;
}

.error-message.active {
    display: block;
}

.loading-spinner {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 50px;
    height: 50px;
    border: 5px solid var(--secondary-color);
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    display: none;
    z-index: 103;
}

@keyframes spin {
    0% { transform: translate(-50%, -50%) rotate(0deg); }
    100% { transform: translate(-50%, -50%) rotate(360deg); }
}

/* Settings and Sliders */
.settings-option {
    margin-bottom: 20px;
    width: 100%;
}

.settings-option label {
    display: block;
    margin-bottom: 10px;
    font-weight: bold;
    font-size: 16px;
}

.toggle-switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}

.toggle-switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: background-color .4s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: transform .4s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: #2196F3;
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.slider-container {
    width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.slider-labels {
    display: flex;
    justify-content: space-between;
    width: 100%;
    margin-bottom: 10px;
}

input[type="range"] {
    width: 100%;
    -webkit-appearance: none;
    background: transparent;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 16px;
    width: 16px;
    border-radius: 50%;
    background: var(--primary-color);
    cursor: pointer;
    margin-top: -5px;
}

input[type="range"]::-webkit-slider-runnable-track {
    width: 100%;
    height: 6px;
    background: var(--secondary-color);
    border-radius: 3px;
}

/* Animations */
@keyframes fadeIn {
    0% { opacity: 0; }
    100% { opacity: 1; }
}

@keyframes scaleIn {
    0% { transform: scale(0.8); }
    100% { transform: scale(1); }
}

@keyframes slideUp {
    0% { transform: translateY(20px); opacity: 0; }
    100% { transform: translateY(0); opacity: 1; }
}

.title {
    animation: slideUp var(--transition-speed) ease-in-out;
}

.search-bar,
.menu-btn {
    animation: scaleIn var(--transition-speed) ease-in-out;
}

/* Responsive Design */
@media (max-width: 768px) {
    .book-grid {
        grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    }
    .grid-item {
        max-width: 220px;
        max-height: 330px;
    }
}

@media (max-width: 480px) {
    .book-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }
    .grid-item {
        max-width: 180px;
        max-height: 270px;
    }
}