nginx.conf

server {
    listen 80;
    server_name _;
    port_in_redirect off;
    absolute_redirect off;
    root /usr/share/nginx/html;

    # Security headers (most are already in HTML, but good to have at server level too)
    add_header X-Frame-Options "DENY" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header Referrer-Policy "strict-origin-when-cross-origin" always;

    # Gzip compression
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/javascript application/xml+rss application/json;

    # Cache static assets
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

    # HTML files - shorter cache
    location ~* \.html$ {
        expires 1h;
        add_header Cache-Control "public, must-revalidate";
    }

    # Main location block
    location / {
        try_files $uri $uri/ $uri/index.html =404;
    }

    # Special handling for mathnotes section
    location /mathnotes/ {
        try_files $uri $uri/ $uri/index.html /mathnotes/$uri/index.html =404;
    }

    # Error pages
    error_page 404 /404/index.html;
    location = /404/index.html {
        internal;
    }

    # Sitemap
    location = /sitemap.xml {
        expires 1d;
        add_header Cache-Control "public, must-revalidate";
    }

    # Robots.txt
    location = /robots.txt {
        expires 7d;
        add_header Cache-Control "public";
    }

    # Favicon
    location = /favicon.ico {
        expires 30d;
        add_header Cache-Control "public";
    }

    # Disable access to hidden files
    location ~ /\. {
        deny all;
        access_log off;
        log_not_found off;
    }
}