/* Cipher Station Blog */

*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    --color-text: #1f2933;
    --color-text-muted: #52606d;
    --color-border: #d9e2ec;
    --color-bg: #ffffff;
    --color-bg-soft: #f7f9fb;
    --color-accent: #2c3e50;
    --color-link: #2563eb;
    --max-width: 720px;
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-serif: Georgia, "Times New Roman", Times, serif;
}

html {
    font-size: 100%;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    font-size: 1.0625rem;
    line-height: 1.7;
    color: var(--color-text);
    background: var(--color-bg);
}

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

a:hover {
    text-decoration: underline;
}

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

.container {
    width: 100%;
    max-width: 960px;
    margin: 0 auto;
    padding: 0 1.25rem;
}

/* Header */

.site-header {
    border-bottom: 1px solid var(--color-border);
    background: var(--color-bg);
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    padding-top: 1rem;
    padding-bottom: 1rem;
}

.site-brand {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-accent);
    text-decoration: none;
}

.site-brand:hover {
    text-decoration: none;
}

.site-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem 1.5rem;
    list-style: none;
    font-size: 0.95rem;
}

.site-nav a {
    color: var(--color-text-muted);
}

.site-nav a[aria-current="page"] {
    color: var(--color-accent);
    font-weight: 600;
    text-decoration: none;
}

/* Main */

.page-main {
    padding: 2.5rem 0 3.5rem;
}

.page-intro {
    max-width: var(--max-width);
    margin-bottom: 2rem;
}

.page-title {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    line-height: 1.25;
    font-weight: 700;
    color: var(--color-accent);
    margin-bottom: 0.5rem;
}

.page-subtitle {
    color: var(--color-text-muted);
    font-size: 1.05rem;
}

/* Article list */

.article-list {
    list-style: none;
    display: grid;
    gap: 1.5rem;
}

.article-card {
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
    background: var(--color-bg);
    transition: box-shadow 0.2s ease;
}

.article-card:hover {
    box-shadow: 0 4px 16px rgba(31, 41, 51, 0.08);
}

.article-card-link {
    display: grid;
    grid-template-columns: 140px 1fr;
    gap: 1.25rem;
    color: inherit;
    text-decoration: none;
    padding: 1rem;
}

.article-card-link:hover {
    text-decoration: none;
}

.article-card-image {
    width: 100%;
    aspect-ratio: 4 / 3;
    object-fit: cover;
    border-radius: 4px;
    background: var(--color-bg-soft);
}

.article-card-body h2 {
    font-size: 1.2rem;
    line-height: 1.35;
    margin-bottom: 0.35rem;
    color: var(--color-accent);
}

.article-card-date {
    display: block;
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-bottom: 0.5rem;
}

.article-card-excerpt {
    font-size: 0.95rem;
    color: var(--color-text-muted);
    line-height: 1.6;
}

/* Article page */

.article {
    max-width: var(--max-width);
}

.article-header {
    margin-bottom: 1.5rem;
}

.article-title {
    font-size: clamp(1.75rem, 4vw, 2.35rem);
    line-height: 1.2;
    font-weight: 700;
    color: var(--color-accent);
    margin-bottom: 0.75rem;
}

.article-date {
    display: block;
    font-size: 0.95rem;
    color: var(--color-text-muted);
}

.featured-image {
    width: 100%;
    margin: 1.5rem 0 2rem;
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.article-image {
    width: 100%;
    margin: 1.25rem 0;
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.article-image-grid {
    display: grid;
    gap: 1rem;
    margin: 1.25rem 0;
}

@media (min-width: 640px) {
    .article-image-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.article-content {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--color-text);
}

.article-content > * + * {
    margin-top: 1.25rem;
}

.article-content h2 {
    font-family: var(--font-sans);
    font-size: 1.35rem;
    line-height: 1.3;
    margin-top: 2rem;
    margin-bottom: 0.75rem;
    color: var(--color-accent);
}

.article-content h3 {
    font-family: var(--font-sans);
    font-size: 1.15rem;
    line-height: 1.35;
    margin-top: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--color-accent);
}

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

.article-content li + li {
    margin-top: 0.35rem;
}

.article-content blockquote {
    border-left: 3px solid var(--color-border);
    padding-left: 1rem;
    color: var(--color-text-muted);
    font-style: italic;
}

.article-content a {
    word-break: break-word;
}

.content-placeholder {
    padding: 1.25rem;
    border: 1px dashed var(--color-border);
    border-radius: 6px;
    background: var(--color-bg-soft);
    color: var(--color-text-muted);
    font-family: var(--font-sans);
    font-size: 0.95rem;
}

.back-link {
    display: inline-block;
    margin-top: 2.5rem;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-accent);
}

.back-link:hover {
    text-decoration: underline;
}

/* Footer */

.site-footer {
    border-top: 1px solid var(--color-border);
    background: var(--color-bg-soft);
    padding: 1.5rem 0;
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

.site-footer p + p {
    margin-top: 0.25rem;
}

/* Mobile */

@media (max-width: 640px) {
    .page-main {
        padding: 2rem 0 3rem;
    }

    .article-card-link {
        grid-template-columns: 1fr;
    }

    .article-card-image {
        max-height: 200px;
    }

    .article-content {
        font-size: 1.0625rem;
    }
}