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

body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.7;
    background-color: var(--background-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Light and Dark Theme Variables */
:root {
    --background-color: #f9f9f9;
    --text-color: #333;
    --primary-color: #4CAF50;
    --secondary-color: #007bff;
    --accent-color: #ff4081;
    --button-bg: #4CAF50;
    --button-text: white;
    --hover-bg: #45a049;
    --header-bg: #4CAF50;
    --footer-bg: #333;
}

body.dark-mode {
    --background-color: #1c1c1e;
    --text-color: #f9f9f9;
    --button-bg: #007bff;
    --hover-bg: #0056b3;
    --header-bg: #333;
    --footer-bg: #4CAF50;
}

/* Header Styling */
.site-header {
    background-color: var(--header-bg);
    color: var(--button-text);
    padding: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.brand {
    font-size: 2rem;
    font-weight: 600;
    color: var(--button-text);
    letter-spacing: 1px;
}

.nav-links {
    list-style: none;
    display: flex;
}

.nav-links li {
    margin-left: 25px;
}

.nav-links a {
    color: var(--button-text);
    text-decoration: none;
    font-size: 1.1rem;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: #ddd;
}

/* Dark Mode Switch */
.theme-switch {
    display: flex;
    align-items: center;
    gap: 10px;
}

#themeToggle {
    width: 40px;
    height: 20px;
    appearance: none;
    background-color: #bbb;
    border-radius: 20px;
    position: relative;
    cursor: pointer;
    outline: none;
}

#themeToggle:before {
    content: '';
    width: 16px;
    height: 16px;
    background-color: white;
    border-radius: 50%;
    position: absolute;
    top: 2px;
    left: 2px;
    transition: transform 0.3s ease;
}

#themeToggle:checked:before {
    transform: translateX(20px);
}

/* Main Content Styling */
.container {
    flex-grow: 1;
    padding: 60px 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.pdf-section {
    margin-bottom: 40px;
    background-color: var(--background-color);
    padding: 25px;
    border-radius: 14px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.pdf-section h2 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-color);
}

.pdf-wrapper {
    position: relative;
    margin-bottom: 20px;
}

iframe {
    width: 100%;
    height: 500px;
    border: none;
    border-radius: 8px;
}

.button-group {
    display: flex;
    gap: 20px;
}

.full-screen-button, .share-button {
    padding: 15px 30px;
    background-color: var(--button-bg);
    color: var(--button-text);
    border: none;
    border-radius: 10px;
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 500;
    transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.2s ease;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.full-screen-button:hover, .share-button:hover {
    background-color: var(--hover-bg);
    transform: translateY(-4px);
    box-shadow: 0 6px 15px rgba(0, 0, 0, 0.15);
}

/* Footer Styling */
.site-footer {
    background-color: var(--footer-bg);
    color: var(--button-text);
    text-align: center;
    padding: 20px;
    font-size: 1rem;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
}

/* Modal Styling */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    justify-content: center;
    align-items: center;
}

.modal-content {
    position: relative;
    margin: auto;
    padding: 0;
    width: 90%;
    max-width: 1000px;
    border-radius: 10px;
    background-color: #fff;
    overflow: hidden;
}

.close-button {
    position: absolute;
    top: 15px;
    right: 25px;
    color: #333;
    font-size: 35px;
    font-weight: bold;
    cursor: pointer;
}

#pdfModalContent {
    width: 100%;
    height: 80vh;
    border: none;
    border-radius: 8px;
}

/* Responsive Styling */
@media (max-width: 768px) {
    .pdf-section h2 {
        font-size: 1.5rem;
    }

    iframe {
        height: 350px;
    }

    .navbar {
        flex-direction: column;
        text-align: center;
    }

    .theme-switch {
        margin-top: 15px;
    }

    .button-group {
        flex-direction: column;
        gap: 15px;
    }

    #pdfModalContent {
        height: 70vh;
    }
}