:root {
    --thw-blue: #0074BB;
    --thw-blue-dark: #003B5C;
    --thw-blue-light: #E6F2FA;
    --thw-blue-accent: #005A93;
    --gray-light: #F5F7FA;
    --gray-medium: #E1E5EA;
    --gray-dark: #2C3E50;
    --white: #FFFFFF;
    --text: #333333;
}

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

body {
    font-family: 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Top Bar */
.top-bar {
    background-color: var(--thw-blue-dark);
    color: var(--white);
    padding: 0.5rem 0;
    font-size: 0.9rem;
}

.top-bar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.top-bar a {
    color: var(--white);
    text-decoration: none;
    font-weight: 600;
}

/* Navigation */
nav {
    background-color: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

nav .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo-icon {
    width: 50px;
    height: 50px;
    background-color: var(--thw-blue);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    font-size: 1.2rem;
}

.logo-text {
    font-weight: 700;
    color: var(--thw-blue);
    font-size: 1.1rem;
    line-height: 1.2;
}

.logo-text small {
    display: block;
    font-weight: 400;
    font-size: 0.8rem;
    color: var(--gray-dark);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--gray-dark);
    font-weight: 600;
    transition: color 0.3s;
}

.nav-links a:hover,
.nav-links li.active a {
    color: var(--thw-blue);
}

.mobile-menu {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--thw-blue);
}

/* Hero */
.hero {
    background: linear-gradient(135deg, rgba(0,116,187,0.9) 0%, rgba(0,59,92,0.95) 100%),
                url('../Images/hero-paderborn.jpg');
    background-size: cover;
    background-position: center;
    color: var(--white);
    padding: 8rem 0;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.hero p {
    font-size: 1.3rem;
    max-width: 700px;
    margin: 0 auto 2rem auto;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 700;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background-color: var(--thw-blue-dark);
    color: var(--white);
}

.btn-primary:hover {
    background-color: var(--thw-blue-accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,59,92,0.4);
}

.btn-secondary {
    background-color: var(--white);
    color: var(--thw-blue-dark);
}

.btn-secondary:hover {
    background-color: var(--thw-blue-light);
    transform: translateY(-2px);
}

/* Sections */
.features,
.about,
.projects,
.cta-section,
.content-section {
    padding: 4rem 0;
}

.features,
.projects {
    background-color: var(--gray-light);
}

.about,
.cta-section,
.content-section {
    background-color: var(--white);
}

.section-title {
    text-align: center;
    margin-bottom: 2rem;
}

.section-title h2 {
    color: var(--thw-blue);
    font-size: 2.2rem;
    margin-bottom: 0.5rem;
}

.section-title p {
    color: var(--gray-dark);
    max-width: 700px;
    margin: 0 auto;
}

/* Feature Cards */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    width: 70px;
    height: 70px;
    background-color: var(--thw-blue);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1rem auto;
    font-size: 1.8rem;
}

.feature-card h3 {
    color: var(--thw-blue);
    margin-bottom: 0.5rem;
}

/* Page Header */
.page-header {
    background: linear-gradient(135deg, var(--thw-blue) 0%, var(--thw-blue-dark) 100%);
    color: var(--white);
    padding: 5rem 0 4rem 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.8rem;
    margin-bottom: 1rem;
}

.page-header p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto;
}

/* Breadcrumb */
.breadcrumb {
    background-color: var(--white);
    padding: 1rem 0;
    font-size: 0.9rem;
    border-bottom: 1px solid var(--gray-medium);
}

.breadcrumb ol {
    list-style: none;
    display: flex;
    gap: 0.5rem;
}

.breadcrumb a {
    color: var(--thw-blue);
    text-decoration: none;
}

.breadcrumb a:hover {
    text-decoration: underline;
}

/* Project Filter */
.filter-section {
    padding: 2rem 0;
    background-color: var(--white);
    border-bottom: 1px solid var(--gray-medium);
}

.filter-buttons {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    justify-content: center;
}

.filter-btn {
    padding: 0.6rem 1.4rem;
    border: 2px solid var(--gray-medium);
    background-color: var(--white);
    color: var(--gray-dark);
    border-radius: 25px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
}

.filter-btn:hover,
.filter-btn.active {
    background-color: var(--thw-blue-dark);
    border-color: var(--thw-blue-dark);
    color: var(--white);
}

/* Project Cards */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
    gap: 2rem;
}

.project-card {
    background: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.12);
}

.project-image {
    height: 220px;
    background: linear-gradient(135deg, var(--gray-medium) 0%, #d0d5db 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #666;
    font-weight: 600;
    position: relative;
}

.project-status {
    position: absolute;
    top: 1rem;
    right: 1rem;
    padding: 0.35rem 0.8rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
}

.status-completed {
    background-color: #2E7D32;
    color: white;
}

.status-progress {
    background-color: var(--thw-blue-dark);
    color: white;
}

.status-planned {
    background-color: #757575;
    color: white;
}

.project-content {
    padding: 1.5rem;
}

.project-tag {
    display: inline-block;
    background-color: var(--thw-blue-light);
    color: var(--thw-blue-dark);
    padding: 0.25rem 0.7rem;
    border-radius: 3px;
    font-size: 0.75rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    text-transform: uppercase;
}

.project-content h3 {
    color: var(--thw-blue);
    margin-bottom: 0.75rem;
    font-size: 1.3rem;
}

.project-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    color: var(--gray-dark);
    margin: 1rem 0;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background-color: var(--gray-medium);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background-color: var(--thw-blue-dark);
}

/* CTA Section */
.cta-section {
    text-align: center;
}

.cta-section h2 {
    color: var(--thw-blue);
    font-size: 2.2rem;
    margin-bottom: 1rem;
}

.cta-section p {
    max-width: 600px;
    margin: 0 auto 1.5rem auto;
}

/* Donation Section */
.donation {
    padding: 4rem 0;
    background: linear-gradient(135deg, var(--thw-blue) 0%, var(--thw-blue-dark) 100%);
    color: var(--white);
}

.donation-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.donation h2 {
    font-size: 2.2rem;
    margin-bottom: 1rem;
}

.donation-box {
    background-color: var(--white);
    color: var(--text);
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.donation-box h3 {
    color: var(--thw-blue);
    margin-bottom: 1rem;
}

.bank-details {
    background-color: var(--gray-light);
    padding: 1rem;
    border-radius: 5px;
    margin: 1rem 0;
    font-family: monospace;
    font-size: 1.1rem;
}

/* Footer */
footer {
    background-color: var(--gray-dark);
    color: var(--white);
    padding: 3rem 0 1rem 0;
}

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

.footer-column h4 {
    color: var(--thw-blue-light);
    margin-bottom: 1rem;
}

.footer-column a {
    color: var(--white);
    text-decoration: none;
    display: block;
    margin-bottom: 0.5rem;
}

.footer-column a:hover {
    color: var(--thw-blue-light);
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 1rem;
    text-align: center;
    font-size: 0.9rem;
    color: rgba(255,255,255,0.7);
}

/* Content images */
.content-section img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1,
    .page-header h1 {
        font-size: 2rem;
    }

    .hero p,
    .page-header p {
        font-size: 1.1rem;
    }

    .nav-links {
        display: none;
    }

    .mobile-menu {
        display: block;
    }

    .donation-content {
        grid-template-columns: 1fr;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .btn-secondary {
        margin-left: 0;
        margin-top: 1rem;
    }

    .top-bar .container {
        justify-content: center;
        text-align: center;
        gap: 0.5rem;
    }
}