/* Critical CSS - Above-the-fold styles for LCP optimization */
/* Includes hero section, navigation, and initial content styles */

/* Essential Root Variables */
:root {
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --secondary: #10b981;
    --dark: #0f172a;
    --dark-soft: #1e293b;
    --gray-900: #111827;
    --gray-800: #1f2937;
    --gray-700: #374151;
    --gray-600: #4b5563;
    --gray-500: #6b7280;
    --gray-400: #9ca3af;
    --gray-100: #f3f4f6;
    --gray-50: #f9fafb;
    --white: #ffffff;
    --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, 'Helvetica Neue', Arial, sans-serif;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --gradient-primary: linear-gradient(135deg, #2563eb 0%, #1e40af 100%);
    --blog-max-width: 800px;
}

/* Base Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
    font-family: var(--font-body);
    line-height: 1.7;
    color: var(--gray-700);
    background: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Container */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ========================================
   HEADER/NAV - Critical for initial render
   ======================================== */
.premium-nav {
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(20px);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 0.75rem 0;
}
.nav-wrapper {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
}
.logo-icon { width: 40px; height: 40px; }
.logo-text { display: flex; flex-direction: column; }
.logo-brand { color: white; font-weight: 700; font-size: 1.125rem; line-height: 1.2; }
.logo-tagline { color: rgba(255, 255, 255, 0.7); font-size: 0.75rem; }

/* ========================================
   BLOG POST HERO - LCP CRITICAL ELEMENT
   ======================================== */
.blog-post-hero {
    position: relative;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #2563eb 100%);
    color: white;
    padding: 3rem 0 4rem 0;
    overflow: hidden;
    margin-bottom: 3rem;
    /* Ensure background image renders immediately */
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

.blog-post-hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    opacity: 0.12;
}

.blog-post-hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin: 0 auto;
}

/* Breadcrumb */
.blog-post-breadcrumb {
    margin-bottom: 1.5rem;
}

.breadcrumb-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    font-size: 0.9375rem;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.05);
}

/* Category Badge */
.blog-post-category-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.625rem;
    background: rgba(255, 255, 255, 0.15);
    border: 1px solid rgba(255, 255, 255, 0.25);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 9999px;
    font-size: 0.9375rem;
    font-weight: 700;
    margin-bottom: 2rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.category-icon {
    font-size: 1.125rem;
}

/* Hero Title - Primary LCP Element */
.blog-post-hero-title {
    font-size: 3.5rem;
    font-weight: 900;
    line-height: 1.15;
    margin-bottom: 2rem;
    color: white;
    letter-spacing: -0.02em;
    text-shadow: 0 2px 20px rgba(0, 0, 0, 0.2);
}

/* Hero Meta */
.blog-post-hero-meta {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    color: rgba(255, 255, 255, 0.85);
    font-size: 0.9375rem;
    flex-wrap: wrap;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
}

.meta-icon {
    font-size: 1.125rem;
}

.meta-divider {
    color: rgba(255, 255, 255, 0.4);
    font-weight: 300;
}

/* ========================================
   BLOG POST CONTENT - Initial visible area
   ======================================== */
.blog-post-content {
    padding: 0 1rem;
}

.blog-post-content .container {
    max-width: 800px;
}

/* Key Takeaways Box - Often visible above fold */
.blog-post-content > .container > div:first-child {
    border-radius: 12px;
    margin-bottom: 2rem;
}

/* ========================================
   TYPOGRAPHY - Critical for text rendering
   ======================================== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-body);
    font-weight: 700;
    line-height: 1.2;
    color: var(--dark);
}

h1 { font-size: clamp(1.75rem, 4vw, 2.5rem); margin-bottom: 1rem; }
h2 { font-size: 1.5rem; margin: 2rem 0 1rem; }
h3 { font-size: 1.25rem; margin: 1.5rem 0 0.75rem; }

p { margin-bottom: 1rem; }
a { color: var(--primary); text-decoration: none; }
ul, ol { margin-bottom: 1rem; padding-left: 1.5rem; }
li { margin-bottom: 0.5rem; }
strong { font-weight: 600; }

/* ========================================
   RESPONSIVE - Mobile critical styles
   ======================================== */
@media (max-width: 768px) {
    .container { padding: 0 1rem; }
    .nav-wrapper { padding: 0 1rem; }

    .blog-post-hero {
        padding: 2rem 0 3rem 0;
    }

    .blog-post-hero-title {
        font-size: 2rem;
        margin-bottom: 1.5rem;
    }

    .blog-post-hero-meta {
        gap: 1rem;
    }

    .blog-post-category-badge {
        padding: 0.5rem 1rem;
        font-size: 0.8125rem;
    }
}

@media (max-width: 480px) {
    .blog-post-hero-title {
        font-size: 1.75rem;
    }

    .blog-post-hero-meta {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }

    .meta-divider {
        display: none;
    }
}

/* ========================================
   READING PROGRESS BAR
   ======================================== */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: var(--primary);
    z-index: 1001;
    width: 0;
}

/* ========================================
   PREVENT LAYOUT SHIFT - Reserve space
   ======================================== */
#header-placeholder {
    /* Removed: Header is now inserted before this element, not inside it */
    min-height: 0;
}

/* Image placeholder to prevent CLS */
img {
    max-width: 100%;
    height: auto;
}

/* Hero image specific - prevent layout shift */
.blog-hero-image,
.blog-hero-image img {
    width: 100%;
    aspect-ratio: 1200 / 630;
    object-fit: cover;
    border-radius: 12px;
}