/* ============================================
                       CSS CUSTOM PROPERTIES
                    ============================================ */
:root {
    --color-primary: #0a1a3a;
    --color-accent: #2563eb;
    --color-accent-hover: #1d4ed8;
    --color-accent-light: #dbeafe;
    --color-bg: #f8fafc;
    --color-surface: #ffffff;
    --color-text: #0f172a;
    --color-text-secondary: #475569;
    --color-text-muted: #94a3b8;
    --color-border: #e2e8f0;
    --color-code-bg: #f1f5f9;
    --color-code-border: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 24px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 12px 48px rgba(0, 0, 0, 0.10);
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --max-width: 1200px;
}

/* ============================================
                       RESET & BASE (only what's needed)
                    ============================================ */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.7;
}

a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color var(--transition);
}

    a:hover {
        color: var(--color-accent-hover);
    }

img {
    max-width: 100%;
    display: block;
}

/* We do NOT override .container padding – site.css handles that */

/* ============================================
                       READING PROGRESS BAR (fixed top)
                    ============================================ */
#progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-accent), #7c3aed);
    width: 0%;
    z-index: 9999;
    transition: width 0.1s linear;
    box-shadow: 0 0 12px rgba(37, 99, 235, 0.35);
}

/* ============================================
                       HERO SECTION
                    ============================================ */
.blog-hero {
    background: var(--color-primary);
    padding: 80px 0 64px;
    position: relative;
    overflow: hidden;
}

    .blog-hero::after {
        content: '';
        position: absolute;
        top: -40%;
        right: -10%;
        width: 600px;
        height: 600px;
        background: radial-gradient(circle, rgba(37, 99, 235, 0.12) 0%, transparent 70%);
        border-radius: 50%;
        pointer-events: none;
    }

    .blog-hero::before {
        content: '';
        position: absolute;
        bottom: -30%;
        left: -5%;
        width: 400px;
        height: 400px;
        background: radial-gradient(circle, rgba(124, 58, 237, 0.08) 0%, transparent 70%);
        border-radius: 50%;
        pointer-events: none;
    }

    .blog-hero .container {
        max-width: 1500px;
        margin: 0 auto;
        padding: 0 32px;
        position: relative;
        z-index: 2;
    }

.blog-breadcrumb {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.5);
    margin-bottom: 24px;
    flex-wrap: wrap;
}

    .blog-breadcrumb a {
        color: rgba(255, 255, 255, 0.7);
        transition: color var(--transition);
    }

        .blog-breadcrumb a:hover {
            color: #fff;
        }

    .blog-breadcrumb span {
        color: rgba(255, 255, 255, 0.3);
    }

.blog-category {
    display: inline-block;
    background: rgba(37, 99, 235, 0.2);
    color: #93b4ff;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 4px 16px;
    border-radius: 100px;
    border: 1px solid rgba(37, 99, 235, 0.25);
    margin-bottom: 20px;
}

.blog-hero h1 {
    font-size: clamp(2.2rem, 5vw, 3.6rem);
    font-weight: 800;
    line-height: 1.15;
    color: #ffffff;
    letter-spacing: -0.02em;
    margin-bottom: 20px;
}

    .blog-hero h1 br {
        display: block;
    }

.blog-subtitle {
    font-size: clamp(1.05rem, 1.4vw, 1.25rem);
    color: rgba(255, 255, 255, 0.7);
    max-width: 680px;
    line-height: 1.6;
    margin-bottom: 28px;
    font-weight: 400;
}

.blog-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px 20px;
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.55);
    padding-top: 4px;
}

    .blog-meta span {
        display: inline-flex;
        align-items: center;
        gap: 6px;
    }

    .blog-meta .dot {
        color: rgba(255, 255, 255, 0.2);
    }

    .blog-meta .author {
        color: rgba(255, 255, 255, 0.85);
        font-weight: 500;
    }

/* ============================================
                       MAIN CONTENT LAYOUT
                    ============================================ */
.blog-content {
    padding: 48px 0 80px;
    background: var(--color-bg);
}

    .blog-content .container {
        display: grid;
        grid-template-columns: minmax(0, 1090px) 280px;
        justify-content: center;
        gap: 48px;
    }

/* ============================================
                       TABLE OF CONTENTS (sticky)
                    ============================================ */
.table-of-contents {
    position: sticky;
    top: 32px;
    background: var(--color-surface);
    border-radius: var(--radius-md);
    padding: 28px 24px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-border);
    align-self: start;
}

    .table-of-contents h3 {
        font-size: 0.75rem;
        text-transform: uppercase;
        letter-spacing: 0.08em;
        font-weight: 700;
        color: var(--color-text-secondary);
        margin-bottom: 16px;
        display: flex;
        align-items: center;
        gap: 8px;
    }

        .table-of-contents h3 i {
            color: var(--color-accent);
            font-size: 0.9rem;
        }

    .table-of-contents ol {
        list-style: none;
        padding: 0;
        margin: 0;
        display: flex;
        flex-direction: column;
        gap: 4px;
    }

        .table-of-contents ol li {
            font-size: 0.85rem;
            line-height: 1.4;
        }

            .table-of-contents ol li a {
                display: block;
                padding: 6px 10px;
                border-radius: var(--radius-sm);
                color: var(--color-text-secondary);
                font-weight: 500;
                transition: all var(--transition);
                border-left: 2px solid transparent;
            }

                .table-of-contents ol li a:hover {
                    color: var(--color-accent);
                    background: var(--color-accent-light);
                    border-left-color: var(--color-accent);
                }

                .table-of-contents ol li a.active {
                    color: var(--color-accent);
                    background: var(--color-accent-light);
                    border-left-color: var(--color-accent);
                }

/* ============================================
                       ARTICLE BODY
                    ============================================ */
.blog-article {
    min-width: 0;
    max-width: 820px;
    width: 100%;
}

    .blog-article .lead {
        font-size: 1.2rem;
        font-weight: 400;
        color: var(--color-text-secondary);
        line-height: 1.7;
        margin-bottom: 24px;
        padding: 20px 24px;
        background: var(--color-surface);
        border-radius: var(--radius-md);
        border-left: 4px solid var(--color-accent);
        box-shadow: var(--shadow-sm);
    }

    .blog-article p {
        margin-bottom: 20px;
        font-size: 1rem;
        line-height: 1.8;
        color: var(--color-text);
    }

    .blog-article h2 {
        font-size: 1.75rem;
        font-weight: 700;
        margin-top: 48px;
        margin-bottom: 16px;
        line-height: 1.25;
        letter-spacing: -0.01em;
        color: var(--color-primary);
        display: flex;
        align-items: center;
        gap: 12px;
    }

        .blog-article h2::before {
            content: '';
            display: inline-block;
            width: 6px;
            height: 28px;
            background: var(--color-accent);
            border-radius: 4px;
            flex-shrink: 0;
        }

    .blog-article h3 {
        font-size: 1.2rem;
        font-weight: 600;
        margin-top: 32px;
        margin-bottom: 12px;
        color: var(--color-primary);
    }

    .blog-article ul,
    .blog-article ol {
        margin-bottom: 20px;
        padding-left: 24px;
    }

    .blog-article li {
        margin-bottom: 6px;
        line-height: 1.7;
    }

        .blog-article li::marker {
            color: var(--color-accent);
        }

    /* ============================================
                       CODE BLOCKS
                    ============================================ */
    .blog-article pre {
        background: #0f172a;
        color: #e2e8f0;
        padding: 20px 24px;
        border-radius: var(--radius-sm);
        overflow-x: auto;
        font-family: var(--font-mono);
        font-size: 0.85rem;
        line-height: 1.6;
        margin: 24px 0;
        border: 1px solid #1e293b;
        box-shadow: var(--shadow-sm);
        position: relative;
    }

        .blog-article pre code {
            font-family: inherit;
            color: inherit;
            background: transparent;
            padding: 0;
            border-radius: 0;
            font-size: inherit;
        }

    .blog-article code {
        font-family: var(--font-mono);
        background: var(--color-code-bg);
        padding: 2px 8px;
        border-radius: 4px;
        font-size: 0.85rem;
        color: #1e293b;
        border: 1px solid var(--color-code-border);
    }

    .blog-article pre code .comment {
        color: #94a3b8;
    }

    .blog-article pre code .keyword {
        color: #f472b6;
    }

    .blog-article pre code .string {
        color: #a3e635;
    }

    .blog-article pre code .function {
        color: #60a5fa;
    }

    .blog-article pre code .number {
        color: #fbbf24;
    }

    .blog-article pre code .operator {
        color: #f472b6;
    }

    .blog-article pre code .class {
        color: #60a5fa;
    }

    .blog-article pre code .property {
        color: #fbbf24;
    }

    .blog-article pre .copy-btn {
        position: absolute;
        top: 12px;
        right: 16px;
        background: rgba(255, 255, 255, 0.06);
        border: none;
        color: #94a3b8;
        font-size: 0.8rem;
        padding: 4px 12px;
        border-radius: 6px;
        cursor: pointer;
        transition: all var(--transition);
        font-family: var(--font-sans);
        font-weight: 500;
    }

        .blog-article pre .copy-btn:hover {
            background: rgba(255, 255, 255, 0.12);
            color: #fff;
        }

/* ============================================
                       TIP / NOTE BOXES
                    ============================================ */
.blog-tip,
.blog-note {
    padding: 20px 24px;
    border-radius: var(--radius-sm);
    margin: 28px 0;
    border-left: 4px solid;
    background: var(--color-surface);
    box-shadow: var(--shadow-sm);
}

.blog-tip {
    border-left-color: #2563eb;
    background: #eff6ff;
}

    .blog-tip strong {
        color: #1d4ed8;
    }

.blog-note {
    border-left-color: #7c3aed;
    background: #f5f3ff;
}

    .blog-note strong {
        color: #6d28d9;
    }

    .blog-tip p:last-child,
    .blog-note p:last-child {
        margin-bottom: 0;
    }

    .blog-tip strong,
    .blog-note strong {
        display: block;
        font-size: 0.85rem;
        text-transform: uppercase;
        letter-spacing: 0.04em;
        margin-bottom: 4px;
    }

/* ============================================
                       HR
                    ============================================ */
.blog-article hr {
    border: none;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--color-border), transparent);
    margin: 48px 0;
}

/* ============================================
                       RESPONSIVE
                    ============================================ */
@@media (max-width: 1024px) {
    .blog-content .container {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .table-of-contents {
        position: relative;
        top: 0;
        order: 2;
    }

    .blog-article {
        order: 1;
    }

    .blog-hero h1 {
        font-size: 2.4rem;
    }
}

@@media (max-width: 640px) {
    .blog-hero {
        padding: 48px 0 40px;
    }

        .blog-hero h1 {
            font-size: 1.8rem;
        }

    .blog-subtitle {
        font-size: 1rem;
    }

    .blog-meta {
        font-size: 0.8rem;
        gap: 6px 14px;
    }

    .blog-content {
        padding: 24px 0 56px;
    }

    .blog-article .lead {
        font-size: 1rem;
        padding: 16px 18px;
    }

    .blog-article h2 {
        font-size: 1.4rem;
        margin-top: 32px;
    }

    .blog-article pre {
        padding: 16px;
        font-size: 0.75rem;
        margin: 16px -16px;
        border-radius: 0;
    }

        .blog-article pre .copy-btn {
            top: 8px;
            right: 10px;
            font-size: 0.7rem;
            padding: 2px 10px;
        }

    .table-of-contents {
        padding: 20px 16px;
    }

    .blog-tip,
    .blog-note {
        padding: 16px 18px;
        margin: 20px 0;
    }
}

/* ============================================
                       SCROLL MARGIN for anchor offsets
                    ============================================ */
section[id] {
    scroll-margin-top: 80px;
}

/* ============================================
                       FOOTER (simple override if needed)
                    ============================================ */
.blog-footer {
    border-top: 1px solid var(--color-border);
    padding: 32px 0 40px;
    background: var(--color-surface);
    text-align: center;
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

    .blog-footer a {
        color: var(--color-accent);
    }