/* =============================================
   style.css - Persönliche Website Dr.-Ing. Markus Böhm
   ============================================= */

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
    padding-top: 80px;
}

/* ==================== HEADER ==================== */
header {
    background: #0f172a;
    color: white;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 80px;
}

/* ==================== LOGO ==================== */
.logo {
    text-decoration: none;
    color: white;
}

.logo h1 {
    font-size: 1.55rem;
    font-weight: 700;
    color: white;
    margin-bottom: 2px;
    line-height: 1.1;
}

.logo .tagline {
    font-size: 0.95rem;
    color: #e2e8f0;
    margin: 0;
    font-weight: 400;
    opacity: 0.95;
}

.logo:hover h1,
.logo:hover .tagline {
    color: #bae6fd;
}

.logo a,
.logo h1,
.logo p {
    text-decoration: none;
}

/* Navigation */
.main-nav {
    display: flex;
    gap: 30px;
}

.main-nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

.main-nav a:hover,
.main-nav a.active {
    color: #60a5fa;
}

/* Sprachauswahl */
.language-switcher {
    display: flex;
    gap: 12px;
}

.lang-link {
    font-size: 1.8rem;
    text-decoration: none;
    transition: transform 0.2s;
    padding: 5px;
    border-radius: 8px;
}

.lang-link:hover {
    transform: scale(1.2);
}

.lang-link.active {
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 8px;
}

/* ==================== MAIN CONTENT ==================== */
.main-content {
    max-width: 1200px;
    margin: 40px auto;
    padding: 0 20px;
}

.profile-section {
    background: white;
    padding: 50px 40px;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    text-align: center;
}

.profile-section h2 {
    font-size: 2.4rem;
    margin-bottom: 20px;
    color: #1e2937;
}

.welcome-content p {
    font-size: 1.15rem;
    margin-bottom: 20px;
    color: #4b5563;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 768px) {
    .header-container {
        flex-direction: column;
        padding: 15px 20px;
        gap: 15px;
    }
    
    .main-nav {
        gap: 20px;
        font-size: 1rem;
    }
    
    .profile-section {
        padding: 40px 20px;
    }
    
    .profile-section h2 {
        font-size: 2rem;
    }
}

/* ==================== FOOTER ==================== */
footer {
    background: #0f172a;
    color: #cbd5e1;
    margin-top: 80px;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-column h3,
.footer-column h4 {
    color: white;
    margin-bottom: 15px;
}

.footer-column a {
    color: #cbd5e1;
    text-decoration: none;
    display: block;
    margin-bottom: 8px;
    transition: color 0.3s;
}

.footer-column a:hover {
    color: #60a5fa;
}

.footer-bottom {
    border-top: 1px solid #334155;
    padding-top: 20px;
    text-align: center;
    font-size: 0.95rem;
}

.footer-bottom p {
    margin-bottom: 5px;
}

.made-with {
    color: #64748b;
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

/* ==================== DOWNLOADS SECTION ==================== */
.downloads-section {
    max-width: 1100px;
    margin: 0 auto;
}

.downloads-section h1 {
    text-align: center;
    margin-bottom: 15px;
    font-size: 2.4rem;
}

.downloads-intro {
    text-align: center;
    font-size: 1.15rem;
    color: #64748b;
    margin-bottom: 50px;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
    gap: 30px;
}

.download-card {
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

.download-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.12);
}

.download-image {
    width: 100%;
    height: 220px;
    object-fit: cover;
    background-color: #e2e8f0;
}

.download-info {
    padding: 28px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.download-info h3 {
    font-size: 1.45rem;
    margin-bottom: 12px;
    color: #1e2937;
}

.download-description {
    color: #475569;
    line-height: 1.65;
    margin-bottom: 25px;
    flex-grow: 1;
}

.btn-download {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    background: #1e40af;
    color: white;
    padding: 14px 24px;
    border-radius: 10px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    margin-top: auto;
    width: 100%;
    text-align: center;
}

.btn-download:hover {
    background: #1e3a8a;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(30, 64, 175, 0.3);
}

.file-size {
    font-size: 0.9rem;
    opacity: 0.85;
}

@media (max-width: 768px) {
    .download-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }
    
    .download-card {
        margin: 0 auto;
        max-width: 100%;
    }
    
    .download-image {
        height: 200px;
    }
}

/* ==================== DISSERTATION PAGE ==================== */
.dissertation-section {
    max-width: 900px;
    margin: 0 auto;
}

.dissertation-section h1 {
    text-align: center;
    margin-bottom: 8px;
    font-size: 2.6rem;
}

.dissertation-subtitle {
    text-align: center;
    color: #64748b;
    font-size: 1.25rem;
    margin-bottom: 50px;
}

.dissertation-content {
    background: white;
    padding: 50px 60px;
    border-radius: 16px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.08);
    line-height: 1.85;
}

.dissertation-content h2 {
    margin-top: 45px;
    margin-bottom: 18px;
    color: #1e2937;
    font-size: 1.55rem;
    border-bottom: 2px solid #e2e8f0;
    padding-bottom: 10px;
}

.dissertation-content p {
    margin-bottom: 22px;
    font-size: 1.08rem;
    color: #374151;
}

/* ==================== DISSERTATION DOWNLOAD BOX (NEU) ==================== */
.dissertation-download-box {
    margin-top: 60px;
    padding: 35px;
    background: #f8fafc;
    border: 2px solid #e2e8f0;
    border-radius: 12px;
}

.dissertation-download-inner {
    display: flex;
    align-items: center;
    gap: 35px;
    flex-wrap: wrap;
}

.dissertation-thumbnail {
    flex-shrink: 0;
}

.dissertation-thumbnail img {
    width: 180px;
    height: auto;
    border-radius: 10px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.12);
    border: 1px solid #e2e8f0;
}

.dissertation-thumbnail img:hover {
    transform: scale(1.04);
    transition: transform 0.4s ease;
}

.dissertation-download-content {
    flex: 1;
    min-width: 280px;
}

.dissertation-download-content h3 {
    margin-bottom: 20px;
    color: #1e40af;
}

.btn-download-large {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    background: #1e40af;
    color: white;
    padding: 16px 32px;
    border-radius: 12px;
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 600;
    margin: 15px 0;
    transition: all 0.3s;
}

.btn-download-large:hover {
    background: #1e3a8a;
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(30, 64, 175, 0.4);
}

/* Responsive */
@media (max-width: 768px) {
    .dissertation-download-inner {
        flex-direction: column;
        text-align: center;
    }
    
    .dissertation-thumbnail img {
        width: 220px;
    }
    
    .dissertation-content {
        padding: 35px 25px;
    }
    
    .dissertation-section h1 {
        font-size: 2.2rem;
    }
}

/* ==================== FADE-OUT ==================== */
.fade-out-bottom {
    position: relative;
    display: block;
    padding-bottom: 20px;
    margin-bottom: 0px;
}

.fade-out-bottom::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 140px;
    background: linear-gradient(
        to bottom,
        rgba(255, 255, 255, 0) 30%,
        rgba(255, 255, 255, 0.65) 60%,
        #ffffff 88%
    );
    pointer-events: none;
    z-index: 2;
}

/* ==================== DISSERTATION METADATA ==================== */
.dissertation-metadata {
    margin-top: 60px;
    padding-top: 30px;
    border-top: 1px solid #e2e8f0;
}

.dissertation-metadata h3 {
    margin-bottom: 20px;
    color: #1e2937;
    font-size: 1.35rem;
}

.metadata-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 25px;
    font-size: 1.02rem;
}

.metadata-item {
    background: #f8fafc;
    padding: 18px 22px;
    border-radius: 10px;
    border-left: 4px solid #1e40af;
}

.metadata-item a {
    color: #1e40af;
    text-decoration: none;
    word-break: break-all;
}

.metadata-item a:hover {
    text-decoration: underline;
}

.metadata-item small {
    color: #64748b;
    font-size: 0.95rem;
}

/* ==================== CITATION DOWNLOADS ==================== */
.citation-downloads {
    grid-column: 1 / -1;
    margin-bottom: 20px;
}

.citation-downloads h4 {
    margin-bottom: 15px;
    color: #1e2937;
}

.citation-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 15px;
}

.citation-card {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 16px 20px;
    background: white;
    border: 1px solid #e2e8f0;
    border-radius: 10px;
    text-decoration: none;
    color: #1e2937;
    transition: all 0.3s ease;
}

.citation-card:hover {
    border-color: #1e40af;
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.citation-card img {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

.citation-card strong {
    display: block;
    font-size: 1.05rem;
}

/* ==================== BACK TO TOP ==================== */
.back-to-top {
    text-align: center;
    margin-top: 80px;
    padding-top: 30px;
    border-top: 1px solid #e2e8f0;
}

.back-to-top a {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    color: #64748b;
    text-decoration: none;
    font-size: 1.05rem;
    padding: 10px 24px;
    border: 1px solid #cbd5e1;
    border-radius: 50px;
    transition: all 0.3s ease;
}

.back-to-top a:hover {
    color: #1e40af;
    border-color: #1e40af;
    background-color: #f8fafc;
    transform: translateY(-3px);
}

.back-to-top .arrow {
    font-size: 1.4rem;
    line-height: 1;
}