:root {
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --accent-color: #ef4444;
    /* Red for high impact/warning nature of the topic */
    --accent-hover: #dc2626;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --modal-overlay: rgba(0, 0, 0, 0.7);
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
    --border-radius: 12px;
    --transition-speed: 0.3s;
}

/* Theme: Dark */
.theme-dark {
    --bg-color: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --accent-color: #f87171;
    --accent-hover: #ef4444;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --modal-overlay: rgba(255, 255, 255, 0.1);
}

/* Theme: Sepia */
.theme-sepia {
    --bg-color: #f5f5dc;
    --card-bg: #fff8e7;
    --text-main: #5c4033;
    --text-muted: #8b5a2b;
    --accent-color: #d2691e;
    --accent-hover: #a0522d;
    --shadow-color: rgba(92, 64, 51, 0.15);
}

/* Theme: Slate */
.theme-slate {
    --bg-color: #27272a;
    --card-bg: #3f3f46;
    --text-main: #e4e4e7;
    --text-muted: #a1a1aa;
    --accent-color: #a78bfa;
    --accent-hover: #8b5cf6;
    --shadow-color: rgba(0, 0, 0, 0.4);
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-main);
    line-height: 1.6;
    transition: background-color var(--transition-speed), color var(--transition-speed);
}

header {
    padding: 2rem 1rem;
    text-align: center;
    max-width: 1200px;
    margin: 0 auto;
}

.banner {
    width: 100%;
    max-height: 400px;
    object-fit: cover;
    border-radius: var(--border-radius);
    margin-bottom: 1.5rem;
    box-shadow: 0 10px 25px -5px var(--shadow-color), 0 8px 10px -6px var(--shadow-color);
    transition: transform 0.3s ease;
}

.banner:hover {
    transform: scale(1.01);
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    background: linear-gradient(to right, var(--text-main), var(--accent-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 800;
}

.controls {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 1.5rem 0;
    flex-wrap: wrap;
}

button {
    background: var(--card-bg);
    border: 1px solid var(--text-muted);
    color: var(--text-main);
    padding: 0.5rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    font-family: inherit;
    font-weight: 600;
    transition: all 0.2s ease;
    box-shadow: 0 2px 4px var(--shadow-color);
}

button:hover {
    background: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
    transform: translateY(-1px);
}

.search-container {
    max-width: 600px;
    margin: 0 auto 2rem;
    padding: 0 1rem;
}

#searchInput {
    width: 100%;
    padding: 1rem;
    border-radius: var(--border-radius);
    border: 2px solid var(--text-muted);
    background: var(--card-bg);
    color: var(--text-main);
    font-size: 1rem;
    transition: border-color 0.2s;
}

#searchInput:focus {
    outline: none;
    border-color: var(--accent-color);
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    padding: 1rem;
    max-width: 1400px;
    margin: 0 auto;
}

.card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: 0 4px 6px -1px var(--shadow-color);
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    display: flex;
    flex-direction: column;
    border-top: 4px solid var(--accent-color);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 10px 15px -3px var(--shadow-color);
}

.card h2 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--text-main);
}

.card-summary {
    color: var(--text-muted);
    font-size: 0.95rem;
    flex-grow: 1;
}

.read-more {
    margin-top: 1rem;
    color: var(--accent-color);
    font-weight: 600;
    font-size: 0.9rem;
    align-self: flex-start;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--modal-overlay);
    backdrop-filter: blur(4px);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    padding: 1rem;
}

.modal.active {
    display: flex;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: var(--card-bg);
    width: 100%;
    max-width: 800px;
    max-height: 90vh;
    border-radius: var(--border-radius);
    padding: 2rem;
    position: relative;
    overflow-y: auto;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    border-top: 6px solid var(--accent-color);
}

.close-modal {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    font-size: 2rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: color 0.2s;
}

.close-modal:hover {
    color: var(--accent-color);
}

.modal-body {
    margin-top: 1.5rem;
}

.modal-body h2 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.modal-body p {
    margin-bottom: 1rem;
}

.modal-body blockquote {
    border-left: 4px solid var(--text-muted);
    padding-left: 1rem;
    margin: 1rem 0;
    font-style: italic;
    color: var(--text-muted);
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

@media (max-width: 768px) {
    .grid-container {
        grid-template-columns: 1fr;
    }

    h1 {
        font-size: 1.75rem;
    }
}