/* Modern Dark Blue Theme - Responsive Design */
:root {
    --primary-dark: #0a192f;
    --primary-blue: #1e3a5f;
    --accent-blue: #2d5aa0;
    --light-blue: #4a90e2;
    --text-light: #e8f4f8;
    --text-gray: #b8c5d1;
    --border-color: #2a4a6b;
    --hover-blue: #3d6bb3;
    --card-bg: #152238;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-blue) 100%);
    color: var(--text-light);
    line-height: 1.7;
    font-size: 16px;
    min-height: 100vh;
}

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

/* Header */
header {
    background: rgba(10, 25, 47, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 2px solid var(--border-color);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--light-blue);
    text-decoration: none;
}

/* Language Switcher */
.language-switcher {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.language-switcher a {
    padding: 8px 16px;
    background: var(--card-bg);
    color: var(--text-light);
    text-decoration: none;
    border-radius: 6px;
    border: 1px solid var(--border-color);
    transition: all 0.3s ease;
    font-size: 0.9rem;
}

.language-switcher a:hover,
.language-switcher a.active {
    background: var(--accent-blue);
    border-color: var(--light-blue);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(77, 144, 226, 0.3);
}

/* Navigation */
nav {
    background: var(--card-bg);
    padding: 1rem 0;
    margin: 1rem 0;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

nav ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    justify-content: center;
}

nav a {
    color: var(--text-light);
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 6px;
    transition: all 0.3s ease;
    display: block;
}

nav a:hover {
    background: var(--accent-blue);
    color: var(--text-light);
}

/* Hero Section */
.hero {
    text-align: center;
    padding: 3rem 0;
    background: linear-gradient(135deg, rgba(30, 58, 95, 0.5) 0%, rgba(10, 25, 47, 0.8) 100%);
    border-radius: 12px;
    margin: 2rem 0;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--light-blue);
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

/* Content Sections */
.content-section {
    background: var(--card-bg);
    padding: 2.5rem;
    margin: 2rem 0;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
}

h2 {
    color: var(--light-blue);
    font-size: 2rem;
    margin: 2rem 0 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--accent-blue);
}

h3 {
    color: var(--accent-blue);
    font-size: 1.5rem;
    margin: 1.5rem 0 1rem;
}

h4 {
    color: var(--text-gray);
    font-size: 1.2rem;
    margin: 1rem 0 0.5rem;
}

p {
    margin: 1rem 0;
    color: var(--text-gray);
}

/* Images */
img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 1.5rem 0;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
    display: block;
}

.content-section img {
    max-width: 600px;
    margin: 1.5rem auto;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 2rem 0;
    background: var(--primary-dark);
    border-radius: 8px;
    overflow: hidden;
}

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

th {
    background: var(--accent-blue);
    color: var(--text-light);
    font-weight: 600;
}

tr:hover {
    background: rgba(77, 144, 226, 0.1);
}

/* Lists */
ul, ol {
    margin: 1rem 0;
    padding-left: 2rem;
    color: var(--text-gray);
}

li {
    margin: 0.5rem 0;
}

/* Links */
a {
    color: var(--light-blue);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--hover-blue);
    text-decoration: underline;
}

/* FAQ Section */
.faq-section {
    margin: 3rem 0;
}

.faq-item {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin: 1rem 0;
    overflow: hidden;
}

.faq-question {
    padding: 1.25rem;
    background: var(--primary-blue);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: background 0.3s ease;
    font-weight: 600;
    color: var(--text-light);
}

.faq-question:hover {
    background: var(--accent-blue);
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--light-blue);
    transition: transform 0.3s ease;
}

.faq-question.active::after {
    content: '−';
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding: 0 1.25rem;
}

.faq-answer.active {
    max-height: 1000px;
    padding: 1.25rem;
    color: var(--text-gray);
}

/* Footer */
footer {
    background: var(--primary-dark);
    padding: 2rem 0;
    margin-top: 4rem;
    border-top: 2px solid var(--border-color);
    text-align: center;
    color: var(--text-gray);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 1.8rem;
    }
    
    h2 {
        font-size: 1.5rem;
    }
    
    h3 {
        font-size: 1.2rem;
    }
    
    .content-section {
        padding: 1.5rem;
    }
    
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    
    table {
        font-size: 0.9rem;
    }
    
    th, td {
        padding: 8px 10px;
    }
}

@media (max-width: 480px) {
    .hero h1 {
        font-size: 1.5rem;
    }
    
    .content-section {
        padding: 1rem;
    }
    
    .language-switcher {
        justify-content: center;
    }
}

/* Internal Links Styling */
.internal-link {
    color: var(--light-blue);
    font-weight: 500;
    border-bottom: 1px dotted var(--light-blue);
}

.internal-link:hover {
    color: var(--hover-blue);
    border-bottom-color: var(--hover-blue);
}