/* style.css */

/* --- CSS Variables for easy theme management --- */
:root {
    --primary-color: #007bff; /* A vibrant blue for main actions */
    --secondary-color: #28a745; /* A vibrant green for success/positive actions */
    --accent-color: #ffc107; /* A vibrant yellow for highlights */
    --text-color: #333;
    --light-text-color: #fff;
    --background-light: #f8f9fa; /* Light background */
    --background-dark: #343a40; /* Dark background for footer/header contrast */
    --card-bg-color: #ffffff; /* White background for cards */
    --border-color: #dee2e6;
    --shadow-light: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.2);
    --transition-speed: 0.3s; /* For smooth animations */
}

/* --- Global Styles --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Poppins', sans-serif; /* Modern font, consider importing from Google Fonts */
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-light);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

h1, h2, h3, h4, h5, h6 {
    color: var(--primary-color);
    margin-bottom: 0.8em;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-speed);
}

a:hover {
    color: var(--secondary-color);
}

/* --- Header --- */
.main-header {
    background-color: var(--background-dark);
    color: var(--light-text-color);
    padding: 1rem 0;
    box-shadow: 0 2px 5px var(--shadow-light);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap; /* Allow wrapping on small screens */
}

.logo {
    margin: 0;
    font-size: 1.8rem;
    font-weight: 700;
}

.logo a {
    color: var(--light-text-color);
}

.logo a:hover {
    color: var(--accent-color);
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
    flex-wrap: wrap; /* Allow wrapping on small screens */
}

.main-nav ul li a {
    color: var(--light-text-color);
    padding: 0.5rem 1rem;
    transition: background-color var(--transition-speed), color var(--transition-speed);
    border-radius: 5px;
}

.main-nav ul li a:hover,
.main-nav ul li a.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--accent-color);
}

/* --- Main Content Layout --- */
.main-content {
    flex: 1; /* Allows main content to grow and push footer down */
    padding: 40px 15px;
}

/* --- Browse Controls (Search & Filter) --- */
.browse-controls {
    display: flex;
    flex-direction: column; /* Stack on small screens */
    gap: 20px;
    margin-bottom: 40px;
    padding: 20px;
    background-color: var(--card-bg-color);
    border-radius: 10px;
    box-shadow: 0 5px 15px var(--shadow-light);
}

.search-bar, .filter-controls {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.search-bar input[type="text"],
.filter-controls select {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    outline: none;
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

.search-bar input[type="text"]:focus,
.filter-controls select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.25);
}

.search-bar button,
.load-more-btn,
.btn { /* General button style */
    background-color: var(--primary-color);
    color: var(--light-text-color);
    border: none;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: background-color var(--transition-speed), transform 0.2s, box-shadow var(--transition-speed);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.search-bar button:hover,
.load-more-btn:hover,
.btn:hover {
    background-color: darken(var(--primary-color), 10%); /* This won't work in pure CSS, but gives the idea */
    filter: brightness(1.1); /* A simple hover effect */
    transform: translateY(-2px);
    box-shadow: 0 4px 10px var(--shadow-medium);
}

.search-bar button i {
    font-size: 1.1rem;
}

/* --- Ebook Grid --- */
.ebook-grid-section h2 {
    text-align: center;
    margin-bottom: 30px;
    font-size: 2.2rem;
    color: var(--text-color);
}

.ebook-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); /* Responsive grid */
    gap: 30px;
    padding-bottom: 40px;
}

.ebook-item {
    background-color: var(--card-bg-color);
    border-radius: 12px;
    box-shadow: 0 8px 25px var(--shadow-light); /* More pronounced shadow */
    overflow: hidden;
    text-align: center;
    padding: 20px;
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.ebook-item:hover {
    transform: translateY(-8px); /* Lift effect on hover */
    box-shadow: 0 15px 30px var(--shadow-medium);
}

.ebook-item img {
    max-width: 100%;
    height: 200px; /* Fixed height for consistency */
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 15px;
    transition: transform var(--transition-speed);
}

.ebook-item:hover img {
    transform: scale(1.03); /* Subtle zoom on image */
}

.ebook-item h3 {
    font-size: 1.4rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.ebook-item p {
    font-size: 0.95rem;
    color: #666;
    margin-bottom: 15px;
    flex-grow: 1; /* Pushes button to the bottom */
}

.ebook-item .view-details-btn {
    background-color: var(--secondary-color);
    color: var(--light-text-color);
    width: 100%;
    padding: 10px 15px;
    border-radius: 6px;
    font-weight: 500;
}

.ebook-item .view-details-btn:hover {
    background-color: darken(var(--secondary-color), 10%); /* Again, for pure CSS, use filter */
    filter: brightness(1.1);
}

.load-more-btn {
    display: block; /* Make it block to take full width */
    margin: 40px auto 20px auto; /* Center the button */
    padding: 12px 25px;
    font-size: 1.1rem;
    background-color: var(--primary-color);
}

/* --- General Button Styles (for modals, etc.) --- */
.btn {
    text-align: center;
}

.btn.primary-btn {
    background-color: var(--primary-color);
}

.btn.primary-btn:hover {
    background-color: darken(var(--primary-color), 10%);
    filter: brightness(1.1);
}

.btn.secondary-btn {
    background-color: var(--accent-color);
    color: var(--text-color); /* Darker text for yellow background */
}

.btn.secondary-btn:hover {
    background-color: darken(var(--accent-color), 10%);
    filter: brightness(1.1);
}


/* --- Modal Styles --- */
.modal {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 1000; /* Sit on top */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: auto; /* Enable scroll if needed */
    background-color: rgba(0, 0, 0, 0.7); /* Black w/ opacity */
    justify-content: center; /* Center content horizontally */
    align-items: center; /* Center content vertically */
    padding: 20px;
    animation: fadeIn 0.3s ease-out;
}

.modal-content {
    background-color: var(--card-bg-color);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px var(--shadow-medium);
    position: relative;
    width: 95%;
    max-width: 550px;
    animation: slideInUp 0.4s ease-out;
}

/* Auth Modal Specifics */
.auth-modal-content { /* Assuming a class for auth modal content if needed */
    max-width: 450px;
}

.auth-tabs {
    display: flex;
    margin-bottom: 25px;
    border-bottom: 2px solid var(--border-color);
}

.tab-button {
    flex: 1;
    padding: 15px 0;
    background: none;
    border: none;
    font-size: 1.1rem;
    font-weight: 600;
    color: #666;
    cursor: pointer;
    transition: color var(--transition-speed), border-bottom var(--transition-speed);
    border-bottom: 2px solid transparent;
}

.tab-button:hover {
    color: var(--primary-color);
}

.tab-button.active {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

.auth-form-content {
    display: none;
    padding-top: 15px;
}

.auth-form-content.active {
    display: block;
}

.auth-form-content h3 {
    text-align: center;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input[type="email"],
.form-group input[type="password"],
.form-group input[type="text"] {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

.form-group input:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.25);
    outline: none;
}

.submit-btn {
    width: 100%;
    padding: 12px;
    margin-top: 15px;
    background-color: var(--primary-color);
    color: var(--light-text-color);
    border: none;
    border-radius: 8px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color var(--transition-speed), transform 0.2s, box-shadow var(--transition-speed);
}

.submit-btn:hover {
    background-color: darken(var(--primary-color), 10%);
    filter: brightness(1.1);
    transform: translateY(-2px);
    box-shadow: 0 4px 10px var(--shadow-medium);
}

.forgot-password-link {
    text-align: center;
    margin-top: 15px;
    font-size: 0.9rem;
    color: var(--primary-color);
    cursor: pointer;
    transition: color var(--transition-speed);
}

.forgot-password-link:hover {
    color: var(--secondary-color);
    text-decoration: underline;
}

.auth-message {
    text-align: center;
    margin-top: 20px;
    padding: 10px 15px;
    border-radius: 8px;
    font-weight: 500;
    opacity: 0; /* Hidden by default */
    transform: translateY(10px);
    transition: opacity 0.4s ease-out, transform 0.4s ease-out;
}

.auth-message.info {
    background-color: #e7f3fe; /* Light blue */
    color: #007bff;
    opacity: 1;
    transform: translateY(0);
}

.auth-message.success {
    background-color: #d4edda; /* Light green */
    color: #155724;
    opacity: 1;
    transform: translateY(0);
}

.auth-message.error {
    background-color: #f8d7da; /* Light red */
    color: #721c24;
    opacity: 1;
    transform: translateY(0);
}


/* Ebook Details Modal Specifics */
.ebook-modal-content {
    max-width: 800px;
    display: flex;
    flex-direction: column;
    gap: 25px;
}

.ebook-details-header {
    display: flex;
    flex-direction: column; /* Stack on small screens */
    align-items: center;
    text-align: center;
    gap: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.ebook-details-header img {
    width: 180px;
    height: 250px;
    object-fit: cover;
    border-radius: 10px;
    box-shadow: 0 5px 15px var(--shadow-light);
}

.ebook-info h2 {
    font-size: 2.2rem;
    margin-bottom: 10px;
    color: var(--primary-color);
}

.ebook-info p {
    font-size: 1rem;
    margin-bottom: 5px;
}

.ebook-description,
.ebook-specs {
    background-color: var(--background-light);
    padding: 15px 20px;
    border-radius: 10px;
    box-shadow: inset 0 1px 5px rgba(0,0,0,0.05); /* Subtle inner shadow */
}

.ebook-description h3,
.ebook-specs h3,
.ebook-preview-section h3 {
    color: var(--primary-color);
    font-size: 1.3rem;
    margin-bottom: 10px;
}

.ebook-description p {
    font-size: 1rem;
    color: #555;
}

.ebook-specs p {
    font-size: 0.95rem;
    margin-bottom: 5px;
}
.ebook-specs span {
    font-weight: 600;
    color: var(--text-color);
}


.ebook-preview-section {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.preview-container {
    background-color: #e9ecef; /* Lighter background for preview */
    padding: 15px;
    border-radius: 10px;
    min-height: 150px; /* Ensure some visible height */
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    position: relative;
    overflow: hidden; /* Hide overflow for page transitions */
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.1);
}

.preview-page {
    position: absolute; /* Position pages absolutely for transitions */
    width: calc(100% - 30px); /* Adjust for padding */
    height: calc(100% - 70px); /* Adjust for navigation bar height */
    display: none; /* Controlled by JS */
    text-align: center;
    padding-top: 20px;
    font-style: italic;
    color: #777;
    background-color: var(--card-bg-color);
    border-radius: 8px;
    box-shadow: 0 2px 10px var(--shadow-light);
    transform: translateX(100%); /* Start off-screen to the right */
    transition: transform 0.5s ease-out;
}

.preview-page[style*="block"] { /* When display is block via JS */
    transform: translateX(0); /* Move to center */
}

.preview-navigation {
    position: absolute;
    bottom: 15px;
    left: 15px;
    right: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: rgba(255, 255, 255, 0.8);
    padding: 8px 15px;
    border-radius: 25px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.15);
    backdrop-filter: blur(5px); /* Glassmorphism effect */
}

.preview-navigation button {
    background: none;
    border: none;
    font-size: 1.1rem;
    color: var(--primary-color);
    cursor: pointer;
    transition: color var(--transition-speed), transform 0.2s;
    padding: 5px 10px;
    border-radius: 5px;
}

.preview-navigation button:hover {
    color: var(--secondary-color);
    transform: scale(1.1);
}
.preview-navigation span {
    font-weight: 600;
    color: var(--text-color);
}


.ebook-actions {
    display: flex;
    flex-direction: column; /* Stack buttons on small screens */
    gap: 15px;
    margin-top: 20px;
}

.ebook-actions .btn {
    width: 100%;
    text-align: center;
    padding: 12px 20px;
    font-size: 1.1rem;
}


.close-button {
    position: absolute;
    top: 15px;
    right: 15px;
    font-size: 2.2rem;
    font-weight: bold;
    color: #aaa;
    cursor: pointer;
    transition: color var(--transition-speed), transform 0.2s;
}

.close-button:hover,
.close-button:focus {
    color: #777;
    transform: rotate(90deg);
}


/* --- Footer --- */
.main-footer {
    background-color: var(--background-dark);
    color: var(--light-text-color);
    padding: 2rem 0;
    text-align: center;
    margin-top: auto; /* Pushes footer to the bottom */
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
}

.footer-content p {
    margin: 0;
    font-size: 0.9rem;
}

.social-links a {
    color: var(--light-text-color);
    margin: 0 10px;
    font-size: 1.5rem;
    transition: color var(--transition-speed), transform 0.2s;
}

.social-links a:hover {
    color: var(--accent-color);
    transform: translateY(-3px);
}

/* --- Responsive Adjustments --- */
/* Medium screens (e.g., tablets) */
@media (min-width: 768px) {
    .header-content {
        flex-direction: row; /* Header elements in a row */
    }

    .main-nav ul {
        flex-wrap: nowrap; /* Prevent nav items from wrapping */
    }

    .browse-controls {
        flex-direction: row; /* Search and filter side-by-side */
        justify-content: space-between;
    }

    .search-bar, .filter-controls {
        flex-basis: 48%; /* Take roughly half width */
        flex-wrap: nowrap;
    }

    .ebook-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); /* Slightly larger cards */
    }

    .ebook-details-header {
        flex-direction: row; /* Image and info side-by-side in modal */
        text-align: left;
        align-items: flex-start;
    }

    .ebook-actions {
        flex-direction: row; /* Buttons side-by-side in modal */
        justify-content: center;
    }
}

/* Large screens (e.g., desktops) */
@media (min-width: 1024px) {
    .ebook-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); /* Even larger cards */
    }

    .modal-content {
        padding: 40px;
    }

    .ebook-modal-content {
        max-width: 900px;
        flex-direction: row;
        gap: 30px;
        flex-wrap: wrap; /* Allow wrapping for sections within the modal */
    }

    .ebook-details-header {
        flex-basis: 100%; /* Take full width of modal */
        margin-bottom: 20px;
    }

    .ebook-description,
    .ebook-specs,
    .ebook-preview-section {
        flex-basis: calc(50% - 15px); /* Divide space for sections */
    }

    .ebook-actions {
        flex-basis: 100%;
        margin-top: 0; /* Remove top margin */
        justify-content: space-around;
    }
}

/* --- Keyframe Animations --- */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideInUp {
    from { transform: translateY(50px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

body {
    font-family: 'Poppins', 'Segoe UI', Arial, sans-serif;
    background: linear-gradient(135deg, #f5d6e6 0%, #a8edea 100%);
    min-height: 100vh;
    margin: 0;
    color: #222;
    transition: background 0.3s;
}

.dark-mode {
    background: linear-gradient(135deg, #232526 0%, #414345 100%);
    color: #f7f7f7;
}

.toast {
    position: fixed;
    left: 50%;
    bottom: 40px;
    transform: translateX(-50%);
    background: linear-gradient(90deg, #fc466b 0%, #3f5efb 100%);
    color: #fff;
    padding: 1rem 2rem;
    border-radius: 2rem;
    box-shadow: 0 6px 30px rgba(63,95,251,0.2);
    opacity: 0;
    z-index: 9999;
    transition: opacity 0.4s, bottom 0.4s;
    font-size: 1.15rem;
}
.toast.visible { opacity: 1; bottom: 60px; }

.modal {
    display: none;
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background: rgba(20,20,60,0.35);
    justify-content: center; align-items: center;
    z-index: 1000;
    transition: background 0.3s;
}
.modal.active { display: flex; }

.modal-content {
    background: rgba(255,255,255,0.87);
    border-radius: 2rem;
    box-shadow: 0 10px 40px rgba(0,0,0,0.25);
    padding: 2rem;
    max-width: 95vw;
    width: 400px;
    position: relative;
    animation: popIn 0.5s cubic-bezier(.18,.89,.32,1.28);
}
@keyframes popIn {
    0% { transform: scale(0.7); opacity: 0; }
    100% { transform: scale(1); opacity: 1; }
}

.tab-button {
    background: linear-gradient(90deg, #36d1c4, #5b86e5);
    color: white;
    border: none;
    padding: 0.7rem 1.7rem;
    border-radius: 1.5rem;
    margin: 0 0.5rem;
    transition: background 0.3s, color 0.3s;
}
.tab-button.active,
.tab-button:hover {
    background: linear-gradient(90deg, #ff7eb3, #65e8c4);
    color: #fff;
}

input, select, button {
    border-radius: 1.5rem;
    border: none;
    padding: 0.8rem 1.1rem;
    margin-bottom: 1rem;
    width: 100%;
    font-size: 1rem;
    background: #f8f9fa;
    transition: box-shadow 0.2s;
}
input:focus, select:focus {
    outline: none;
    box-shadow: 0 0 0 2px #36d1c4;
}

.ebook-item {
    background: rgba(255,255,255,0.7);
    border-radius: 1.2rem;
    box-shadow: 0 2px 12px rgba(40,40,120,0.14);
    margin-bottom: 1.5rem;
    overflow: hidden;
    text-align: center;
    padding: 1.3rem;
    transition: transform 0.2s;
}
.ebook-item:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 8px 32px rgba(40,40,120,0.22);
}

.view-details-btn {
    background: linear-gradient(90deg, #fc466b, #3f5efb);
    color: #fff;
    border: none;
    padding: 0.7rem 1.4rem;
    border-radius: 1.2rem;
    transition: background 0.3s;
}
.view-details-btn:hover {
    background: linear-gradient(90deg, #43e97b, #38f9d7);
}

@media (max-width: 600px) {
    .modal-content { width: 95vw; padding: 1rem; }
    .ebook-item { padding: 0.7rem; }
    .tab-button { padding: 0.6rem 1rem; font-size: 0.95rem; }
    input, select, button { font-size: 0.97rem; }
}
/* Optional: Import Poppins font from Google Fonts if not already in your project */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700&display=swap');