:root {
    --primary-color: #0d47a1; /* Deep Blue */
    --secondary-color: #d32f2f; /* Strong Red for accents */
    --background-color: #f8f9fa; /* Light Gray */
    --surface-color: #ffffff; /* White for cards */
    --text-color: #212529; /* Dark Charcoal */
    --light-text-color: #6c757d; /* Lighter gray for meta */
    --border-color: #dee2e6;
    --font-family: 'Poppins', sans-serif;
    --header-height: 70px;
}

/* Global Reset & Base Styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.7;
    font-size: 16px;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 0.75rem;
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; color: var(--primary-color); }
p { margin-bottom: 1.5rem; }
a { color: var(--primary-color); text-decoration: none; transition: color 0.3s ease; }
a:hover { color: var(--secondary-color); text-decoration: underline; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style-position: inside; }

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

/* Header & Navigation */
.site-header {
    background-color: var(--surface-color);
    border-bottom: 1px solid var(--border-color);
    padding: 0 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: var(--header-height);
    max-width: 1200px;
    margin: 0 auto;
}

.site-title a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
    text-decoration: none;
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

.main-nav a {
    font-weight: 500;
    font-size: 1rem;
    color: var(--text-color);
    text-decoration: none;
    padding: 0.5rem 0;
    position: relative;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.main-nav a:hover::after,
.main-nav a.active::after {
    width: 100%;
}

/* Main Layout */
.main-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 2rem 0;
}

.main-content, .sidebar {
    background-color: var(--surface-color);
    padding: 2rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
}

/* Article Grid */
.article-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

.article-card {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
    transition: box-shadow 0.3s ease;
}

.article-card:hover {
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.card-content {
    padding: 1.5rem;
}

.card-content h2 {
    font-size: 1.5rem;
    margin-top: 0;
}

.read-more-btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 0.6rem 1.2rem;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 500;
    transition: background-color 0.3s ease;
}

.read-more-btn:hover {
    background-color: var(--secondary-color);
    color: #fff;
    text-decoration: none;
}

/* Sidebar */
.sidebar-widget {
    margin-bottom: 2.5rem;
}

.sidebar-widget:last-child {
    margin-bottom: 0;
}

.widget-title {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 0.5rem;
    display: inline-block;
}

.sidebar-widget ul {
    list-style: none;
}

.sidebar-widget ul li {
    margin-bottom: 0.75rem;
}

.sidebar-widget ul li a::before {
    content: '»';
    margin-right: 8px;
    color: var(--secondary-color);
}

/* Article Page Specifics */
.article-header {
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1.5rem;
}

.article-meta {
    font-size: 0.9rem;
    color: var(--light-text-color);
    margin-top: -0.5rem;
    margin-bottom: 1rem;
}

.article-meta span {
    margin-right: 1rem;
}

.article-content h2, .article-content h3 {
    margin-top: 2rem;
}

.cta-box {
    background-color: var(--background-color);
    border: 2px dashed var(--primary-color);
    padding: 1.5rem;
    margin: 2rem 0;
    text-align: center;
    border-radius: 8px;
}
.cta-box p { margin-bottom: 1rem; }

/* Footer */
.site-footer {
    background-color: var(--text-color);
    color: #fff;
    text-align: center;
    padding: 2rem 1rem;
    margin-top: 2rem;
}

/* Responsive Design */
@media (min-width: 768px) {
    .article-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 992px) {
    .main-layout {
        grid-template-columns: 2fr 1fr;
    }
}