:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #e67e22;
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-main: #333333;
    --text-muted: #7f8c8d;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Helvetica Neue', Helvetica, 'PingFang SC', 'Microsoft YaHei', sans-serif; background-color: var(--bg-color); color: var(--text-main); line-height: 1.6; }
a { text-decoration: none; color: inherit; }
.container { width: 92%; max-width: 1200px; margin: 0 auto; }
header { background-color: var(--primary-color); color: #fff; padding: 1rem 0; position: sticky; top: 0; z-index: 100; box-shadow: 0 2px 10px rgba(0,0,0,0.1); }
header .container { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; }
header h1 { font-size: 1.5rem; font-weight: 600; letter-spacing: 2px;}
nav { display: flex; gap: 20px; }
nav a { font-size: 1rem; opacity: 0.8; transition: opacity 0.3s; }
nav a:hover { opacity: 1; color: var(--accent-color); }

/* Hero / Tool Section */
.hero { background: linear-gradient(135deg, #2c3e50, #4ca1af); color: #fff; padding: 60px 0; text-align: center; }
.tool-box { background: var(--card-bg); padding: 30px; border-radius: 12px; box-shadow: 0 10px 30px rgba(0,0,0,0.2); max-width: 600px; margin: 30px auto 0; color: var(--text-main); }
.tool-box h2 { font-size: 1.8rem; margin-bottom: 10px; color: var(--primary-color); }
.tool-box p.desc { color: var(--text-muted); margin-bottom: 20px; font-size: 0.9rem; }
.form-group { display: flex; gap: 10px; margin-bottom: 20px; }
.form-group input { flex: 1; padding: 12px; border: 1px solid #ccc; border-radius: 6px; font-size: 1rem; }
.form-group button { padding: 12px 24px; border: none; background: var(--accent-color); color: #fff; font-size: 1rem; border-radius: 6px; cursor: pointer; font-weight: bold; transition: background 0.3s; }
.form-group button:hover { background: #d35400; }
#result-container { margin-top: 20px; text-align: left; }
.result-card { background: #ecf0f1; padding: 15px; border-left: 4px solid var(--accent-color); border-radius: 4px; }

/* Grid Sections */
.section-title { font-size: 2rem; text-align: center; margin: 60px 0 30px; color: var(--primary-color); }
.grid-2, .grid-3 { display: grid; gap: 30px; }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(400px, 1fr)); }

.card { background: var(--card-bg); border-radius: 8px; overflow: hidden; box-shadow: 0 4px 6px rgba(0,0,0,0.05); transition: transform 0.3s; }
.card:hover { transform: translateY(-5px); box-shadow: 0 10px 20px rgba(0,0,0,0.1); }
.card img { width: 100%; height: 200px; object-fit: cover; }
.card-content { padding: 20px; }
.card-content h3 { font-size: 1.2rem; margin-bottom: 10px; }
.card-content h3 a:hover { color: var(--accent-color); }
.tag { display: inline-block; padding: 4px 10px; background: var(--bg-color); color: var(--accent-color); font-size: 0.8rem; border-radius: 20px; margin-bottom: 10px; }

/* FAQ Section */
.faq-section { max-width: 800px; margin: 0 auto 60px; }
.faq-item { background: var(--card-bg); margin-bottom: 15px; padding: 20px; border-radius: 8px; box-shadow: 0 2px 4px rgba(0,0,0,0.05); }
.faq-item h4 { font-size: 1.1rem; color: var(--primary-color); margin-bottom: 10px; }
.faq-item p { color: var(--text-muted); font-size: 0.95rem; }

/* Articles Page */
.article-page { max-width: 800px; margin: 40px auto; background: var(--card-bg); padding: 40px; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.05); }
.article-title { font-size: 2.2rem; margin-bottom: 15px; color: var(--primary-color); }
.article-meta { color: var(--text-muted); font-size: 0.9rem; margin-bottom: 30px; border-bottom: 1px solid #eee; padding-bottom: 20px; }
.article-img { width: 100%; height: 350px; object-fit: cover; border-radius: 8px; margin-bottom: 30px; }
.article-content h2 { margin: 30px 0 15px; font-size: 1.5rem; color: var(--secondary-color); }
.article-content p { margin-bottom: 15px; font-size: 1.05rem; }

footer { background: var(--primary-color); color: #bdc3c7; text-align: center; padding: 30px 0; margin-top: 60px; }

@media (max-width: 768px) {
    header .container { flex-direction: column; gap: 15px; }
    .form-group { flex-direction: column; }
    .article-page { padding: 20px; }
    .article-title { font-size: 1.5rem; }
}