/* Font Face Definitions */
@font-face {
    font-family: 'Roboto';
    src: url('/fonts/roboto/Roboto-Regular.ttf') format('truetype');
    font-weight: 400;
    font-style: normal;
}

@font-face {
    font-family: 'Roboto';
    src: url('/fonts/roboto/Roboto-Bold.ttf') format('truetype');
    font-weight: 700;
    font-style: normal;
}

@font-face {
    font-family: 'Roboto';
    src: url('/fonts/roboto/Roboto-Black.ttf') format('truetype');
    font-weight: 900;
    font-style: normal;
}

@font-face {
    font-family: 'Roboto';
    src: url('/fonts/roboto/Roboto-Light.ttf') format('truetype');
    font-weight: 300;
    font-style: normal;
}

/* CSS Custom Properties (Variablen) */
:root {
    --schrift2: 'Roboto', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --schrift1: 'Roboto', Arial, sans-serif;
}

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

body {
    font-family: var(--schrift1);
    line-height: 1.6;
    color: #333;
    background-color: #ffffff;
}

.divider {
    margin: 1em 0em 1em 0em;
}

/* Navigation Styles */
.main-navigation {
    background-color: #1A4273;
    padding: 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
}

.logo a {
    color: white;
    text-decoration: none;
    font-size: 1.5rem;
    font-weight: 600;
    padding: 1rem 0;
    display: block;
    font-family: var(--schrift1);
}

.nav-menu {
    list-style: none;
    display: flex;
    margin: 0;
    padding: 0;
}

.nav-menu li {
    margin: 0;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    padding: 1.2rem 1.5rem;
    display: block;
    transition: background-color 0.3s ease;
    border-bottom: 3px solid transparent;
    font-family: var(--schrift1);
}

.nav-menu a:hover {
    background-color: #009FE3;
    border-bottom-color: white;
}

/* Mobile Menu */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 0.5rem;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: white;
    margin: 3px 0;
    transition: 0.3s;
}

/* Main Content */
.main-content {
    min-height: calc(100vh - 200px);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Book Section */
.book-section {
    text-align: center;
    padding: 3rem 0 2rem;
}

.book-cover-container {
    display: inline-block;
    margin-bottom: 2rem;
}

.book-cover {
    max-width: 300px;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(26, 66, 115, 0.2);
}

/* Welcome Section */
.welcome-section {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 0 4rem;
}

.welcome-intro {
    font-size: 1.2rem;
    line-height: 1.7;
    margin-bottom: 1.5rem;
    color: #444;
    font-family: var(--schrift1);
}

.welcome-description {
    font-size: 1.1rem;
    line-height: 1.6;
    margin-bottom: 1.5rem;
    color: #555;
    font-family: var(--schrift1);
}

.resource-list {
    list-style: none;
    margin: 2rem 0;
    padding-left: 0;
}

.resource-list li {
    margin: 0.8rem 0;
    padding-left: 2rem;
    position: relative;
    font-size: 1.05rem;
    line-height: 1.5;
    font-family: var(--schrift1);
}

.resource-list li:before {
    content: "•";
    color: #009FE3;
    font-size: 1.5rem;
    position: absolute;
    left: 0;
    top: -0.1rem;
}

.closing-note {
    font-size: 1.1rem;
    line-height: 1.6;
    margin-top: 2rem;
    color: #555;
    font-style: italic;
    font-family: var(--schrift1);
}

/* Footer */
.footer {
    background-color: #f8f9fa;
    border-top: 1px solid #e9ecef;
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    color: #1A4273;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    font-family: var(--schrift1);
    font-weight: 700;
}

.footer-section p {
    margin-bottom: 0.5rem;
    color: #666;
    font-size: 0.95rem;
    font-family: var(--schrift1);
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #009FE3;
    text-decoration: none;
    font-size: 0.95rem;
    font-family: var(--schrift1);
}

.footer-section a:hover {
    text-decoration: underline;
}

.footer-bottom {
    border-top: 1px solid #e9ecef;
    padding-top: 1rem;
    text-align: center;
    color: #666;
    font-size: 0.9rem;
    font-family: var(--schrift1);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background-color: #1A4273;
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        transition: left 0.3s ease;
        padding-top: 2rem;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-menu li {
        margin: 0;
        width: 100%;
        text-align: center;
    }

    .nav-menu a {
        padding: 1rem;
        width: 100%;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(-45deg) translate(-5px, 6px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(45deg) translate(-5px, -6px);
    }

    .container {
        padding: 0 1rem;
    }

    .book-cover {
        max-width: 250px;
    }

    .welcome-intro,
    .welcome-description,
    .closing-note {
        font-size: 1rem;
    }

    .resource-list li {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 0 1rem;
    }

    .logo a {
        font-size: 1.2rem;
    }

    .book-cover {
        max-width: 200px;
    }
}