:root {
    --theme-primary: #0ea5e9;
    --theme-secondary: #06b6d4;
}
.text-theme-primary { color: #0ea5e9; }
.text-theme-secondary { color: #06b6d4; }
.bg-theme-primary { background-color: #0ea5e9; }
.bg-theme-secondary { background-color: #06b6d4; }
.btn-primary {
    background: linear-gradient(135deg, #0ea5e9, #06b6d4);
    color: white;
}
.btn-primary:hover {
    background: linear-gradient(135deg, #06b6d4, #0ea5e9);
    color: white;
}

* {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
}
html { scroll-behavior: smooth; }

.bg-grid {
    background-image: linear-gradient(to right, rgba(148, 163, 184, 0.03) 1px, transparent 1px),
        linear-gradient(to bottom, rgba(148, 163, 184, 0.03) 1px, transparent 1px);
    background-size: 100px 100px;
}

.section-tag {
    font-size: 0.7rem;
    letter-spacing: 0.3em;
}

.section-title {
    font-size: 3.5rem;
    font-weight: 200;
    letter-spacing: -0.04em;
    line-height: 1.2;
}

.article-content {
    font-size: 1.125rem;
    line-height: 1.8;
    color: #cbd5e1;
}

.article-content h1, .article-content h2, .article-content h3 {
    color: white;
    font-weight: 500;
    margin-top: 2.5rem;
    margin-bottom: 1.5rem;
}

.article-content p {
    margin-bottom: 1.5rem;
}

.article-content img {
    border-radius: 16px;
    margin: 2rem 0;
    max-width: 100%;
    height: auto;
}

.article-content a {
    color: #38bdf8;
    text-decoration: underline;
    transition: color 0.3s;
}

.article-content a:hover {
    color: #0ea5e9;
}

.article-content ul, .article-content ol {
    margin-bottom: 1.5rem;
    padding-left: 1.5rem;
}

.article-content li {
    margin-bottom: 0.5rem;
}

.article-content table {
    border-collapse: collapse;
    width: 100%;
    margin: 2rem 0;
}

.article-content table,
.article-content th,
.article-content td {
    border: 1px solid #334155;
    padding: 0.75rem;
}

.article-content th {
    background-color: rgba(30, 41, 59, 0.5);
    color: white;
    font-weight: 500;
}

.nav-link {
    position: relative;
    font-weight: 400;
    transition: font-weight 0.3s ease;
}

.fade-in-up {
    opacity: 0;
    transform: translateY(60px);
    transition: all 1.1s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}