:root {
    --bg-color: #f4f4f4;
    --text-color: #333;
    --card-bg: white;
    --card-shadow: rgba(0, 0, 0, 0.1);
    --header-color: #2c3e50;
    --accent-color: #3498db;
    --accent-hover: #2980b9;
    --meta-color: #7f8c8d;
    --description-color: #555;
    --border-radius: 12px;
    --transition: all 0.3s ease;
}

body.dark-mode {
    --bg-color: #1a1a1a;
    --text-color: #e0e0e0;
    --card-bg: #2d2d2d;
    --card-shadow: rgba(0, 0, 0, 0.3);
    --header-color: #ffffff;
    --accent-color: #5dade2;
    --accent-hover: #85c1e9;
    --meta-color: #b0b0b0;
    --description-color: #cccccc;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--bg-color);
    margin: 0;
    padding: 0;
    transition: var(--transition);
}

#app {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--meta-color);
}

.header-content {
    flex: 1;
}

h1 {
    color: var(--header-color);
    font-size: 2.8rem;
    font-weight: 700;
    margin: 0 0 0.5rem 0;
    letter-spacing: -0.02em;
}

.theme-toggle {
    background: none;
    border: 2px solid var(--accent-color);
    border-radius: 50%;
    width: 50px;
    height: 50px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    transition: var(--transition);
    color: var(--accent-color);
}

.theme-toggle:hover {
    background-color: var(--accent-color);
    color: white;
    transform: scale(1.05);
}

.theme-toggle:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

#last-updated {
    text-align: center;
    color: var(--meta-color);
    font-size: 0.95rem;
    margin-bottom: 2rem;
    font-weight: 500;
}

#loading {
    text-align: center;
    color: var(--accent-color);
    font-size: 1.2rem;
    margin: 3rem 0;
    font-weight: 600;
}

#news-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(400px, 1fr));
    gap: 2rem;
}

.news-item {
    background-color: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: 0 4px 20px var(--card-shadow);
    padding: 2rem;
    transition: var(--transition);
    border: 1px solid transparent;
}

.news-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px var(--card-shadow);
    border-color: var(--accent-color);
}

.news-item h2 {
    color: var(--header-color);
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 1rem;
    line-height: 1.3;
    letter-spacing: -0.01em;
}

.news-meta {
    color: var(--meta-color);
    font-size: 0.9rem;
    margin-bottom: 1.2rem;
    font-weight: 500;
}

.news-description {
    color: var(--description-color);
    font-size: 1rem;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.more-details {
    display: inline-flex;
    align-items: center;
    background-color: var(--accent-color);
    color: white;
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition);
    gap: 0.5rem;
}

.more-details:hover {
    background-color: var(--accent-hover);
    transform: translateX(2px);
}

.more-details:focus {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

.more-details::after {
    content: "→";
    font-size: 0.8rem;
    transition: var(--transition);
}

.more-details:hover::after {
    transform: translateX(2px);
}

@media (max-width: 768px) {
    #app {
        padding: 15px;
    }

    h1 {
        font-size: 2rem;
    }

    #news-container {
        grid-template-columns: 1fr;
        gap: 15px;
    }

    .news-item {
        padding: 15px;
    }

    .news-item h2 {
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    #app {
        padding: 10px;
    }

    h1 {
        font-size: 1.8rem;
    }

    .news-item {
        padding: 12px;
    }

    .news-item h2 {
        font-size: 1.1rem;
    }

    .news-description {
        font-size: 0.9rem;
    }

    .more-details {
        padding: 6px 12px;
        font-size: 0.85rem;
    }
}