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

:root {
    --color-bg: #fdfdfd;
    --color-text: #2e2e2e;
    --color-text-light: #6b6b6b;
    --color-accent: #3d5a80;
    --color-accent-hover: #2c4466;
    --color-border: #c8c8c8;
    --color-code-bg: rgba(245, 245, 245, 0.85);
    --font-body: "Georgia", "Times New Roman", serif;
    --font-heading: -apple-system, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
    --font-mono: "SFMono-Regular", "Consolas", "Liberation Mono", "Menlo", monospace;
    --max-width: 42rem;
    --color-glass: rgba(253, 253, 253, 0.6);
    --color-glass-strong: rgba(253, 253, 253, 0.7);
    --color-blockquote-bg: rgba(245, 245, 245, 0.6);
    --color-th-bg: rgba(240, 240, 240, 0.85);
    --color-td-bg: rgba(253, 253, 253, 0.6);
}

html {
    font-size: 18px;
    line-height: 1.7;
    color: var(--color-text);
    background-color: var(--color-bg);
}

body {
    font-family: var(--font-body);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background:
        radial-gradient(circle 320px at 90% 5%,   rgba(167, 139, 250, 0.38), transparent),
        radial-gradient(circle 280px at 10% 12%,  rgba(196, 181, 253, 0.32), transparent),
        radial-gradient(circle 260px at 75% 22%,  rgba(125, 211, 252, 0.30), transparent),
        radial-gradient(circle 300px at 5%  38%,  rgba(110, 231, 183, 0.30), transparent),
        radial-gradient(circle 340px at 85% 42%,  rgba(249, 168, 212, 0.34), transparent),
        radial-gradient(circle 240px at 20% 55%,  rgba(251, 191, 36,  0.28), transparent),
        radial-gradient(circle 280px at 70% 60%,  rgba(196, 181, 253, 0.30), transparent),
        radial-gradient(circle 300px at 10% 72%,  rgba(167, 139, 250, 0.32), transparent),
        radial-gradient(circle 260px at 80% 78%,  rgba(110, 231, 183, 0.28), transparent),
        radial-gradient(circle 320px at 30% 85%,  rgba(249, 168, 212, 0.32), transparent),
        radial-gradient(circle 240px at 90% 92%,  rgba(253, 230, 138, 0.30), transparent),
        radial-gradient(circle 280px at 50% 98%,  rgba(125, 211, 252, 0.28), transparent),
        var(--color-bg);
    background-attachment: fixed;
}

/* Layout */

.site-header {
    padding: 2rem 1.5rem;
    border-bottom: 2px solid var(--color-border);
    text-align: center;
    background: var(--color-glass);
    backdrop-filter: blur(12px);
}

.site-title {
    font-family: var(--font-heading);
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--color-text);
    text-decoration: none;
    letter-spacing: -0.02em;
    transition: color 0.2s ease;
}

.site-title:hover {
    color: var(--color-accent);
}

.content {
    max-width: var(--max-width);
    width: 100%;
    margin: 0 auto;
    padding: 3rem 1.5rem;
    flex: 1;
}

.site-footer {
    padding: 2rem 1.5rem;
    border-top: 2px solid var(--color-border);
    text-align: center;
    font-size: 0.85rem;
    color: var(--color-text-light);
    background: var(--color-glass);
    backdrop-filter: blur(12px);
}

.site-footer a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color 0.2s ease;
}

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

/* Search */

.search-form {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
}

.search-form input[type="search"] {
    flex: 1;
    font-family: var(--font-body);
    font-size: 0.95rem;
    padding: 0.5rem 0.75rem;
    border: 2px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-glass-strong);
    color: var(--color-text);
    outline: none;
    transition: border-color 0.2s ease;
}

.search-form input[type="search"]:focus {
    border-color: var(--color-accent);
}

.search-form button {
    font-family: var(--font-heading);
    font-size: 0.9rem;
    padding: 0.5rem 1.2rem;
    border: 2px solid var(--color-accent);
    border-radius: 6px;
    background: var(--color-accent);
    color: #fff;
    cursor: pointer;
    transition: background 0.2s ease, border-color 0.2s ease;
}

.search-form button:hover {
    background: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
}

.search-results-info {
    font-size: 0.9rem;
    color: var(--color-text-light);
    margin-bottom: 1.5rem;
}

.search-results-info a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color 0.2s ease;
}

.search-results-info a:hover {
    color: var(--color-accent-hover);
}

/* Post list */

.post-summary {
    padding: 1.5rem 0;
    border-bottom: 2px solid var(--color-border);
}

.post-summary:last-child {
    border-bottom: none;
}

.post-summary h2 {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 0.3rem;
}

.post-summary h2 a {
    color: var(--color-text);
    text-decoration: none;
    transition: color 0.2s ease;
}

.post-summary h2 a:hover {
    color: var(--color-accent);
}

.post-summary time {
    font-size: 0.85rem;
    color: var(--color-text-light);
}

/* Post detail */

.post-header {
    margin-bottom: 2.5rem;
}

.post-header h1 {
    font-family: var(--font-heading);
    font-size: 2.2rem;
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: 0.5rem;
}

.post-header time {
    font-size: 0.9rem;
    color: var(--color-text-light);
}

/* Post content (rendered Markdown) */

.post-content h2,
.post-content h3,
.post-content h4 {
    font-family: var(--font-heading);
    margin-top: 2rem;
    margin-bottom: 0.8rem;
    line-height: 1.3;
}

.post-content h2 {
    font-size: 1.5rem;
}

.post-content h3 {
    font-size: 1.25rem;
}

.post-content p {
    margin-bottom: 1.2rem;
}

.post-content a {
    color: var(--color-accent);
    text-decoration: none;
    background-image: linear-gradient(var(--color-accent-hover), var(--color-accent-hover));
    background-size: 0% 1px;
    background-position: left bottom;
    background-repeat: no-repeat;
    padding-bottom: 1px;
    transition: background-size 0.2s ease, color 0.2s ease;
}

.post-content a:hover {
    color: var(--color-accent-hover);
    background-size: 100% 1px;
}

.post-content ul,
.post-content ol {
    margin-bottom: 1.2rem;
    padding-left: 1.5rem;
}

.post-content li {
    margin-bottom: 0.3rem;
}

.post-content blockquote {
    border-left: 4px solid var(--color-accent);
    padding: 0.8rem 1.2rem;
    margin: 1.5rem 0;
    color: var(--color-text-light);
    font-style: italic;
    background: var(--color-blockquote-bg);
    border-radius: 0 6px 6px 0;
}

.post-content pre {
    background: var(--color-code-bg);
    padding: 1.2rem;
    border-radius: 6px;
    border: 1px solid var(--color-border);
    overflow-x: auto;
    margin: 1.5rem 0;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    line-height: 1.5;
}

.post-content code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background: var(--color-code-bg);
    padding: 0.15rem 0.4rem;
    border-radius: 3px;
    border: 1px solid var(--color-border);
}

.post-content pre code {
    background: none;
    padding: 0;
    border-radius: 0;
    border: none;
    font-size: 1em;
}

.post-content img {
    max-width: 100%;
    height: auto;
    border-radius: 6px;
}

.post-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 1.5rem 0;
}

.post-content th,
.post-content td {
    border: 2px solid var(--color-border);
    padding: 0.6rem 0.8rem;
    text-align: left;
}

.post-content th {
    background: var(--color-th-bg);
    font-family: var(--font-heading);
    font-weight: 600;
}

.post-content td {
    background: var(--color-td-bg);
}

.post-content hr {
    border: none;
    border-top: 2px solid var(--color-border);
    margin: 2rem 0;
}

/* Pagination */

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
    margin-top: 2.5rem;
    padding-top: 1.5rem;
    border-top: 2px solid var(--color-border);
}

.pagination a {
    color: var(--color-accent);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

.pagination a:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

.pagination-info {
    font-size: 0.85rem;
    color: var(--color-text-light);
}

/* Navigation */

.back-link {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 2px solid var(--color-border);
}

.back-link a {
    color: var(--color-accent);
    text-decoration: none;
    font-size: 0.95rem;
    transition: color 0.2s ease;
}

.back-link a:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

/* Responsive */

@media (max-width: 600px) {
    html {
        font-size: 16px;
    }

    body {
        background:
            radial-gradient(circle 200px at 90% 5%,   rgba(167, 139, 250, 0.20), transparent),
            radial-gradient(circle 180px at 10% 15%,  rgba(196, 181, 253, 0.18), transparent),
            radial-gradient(circle 160px at 75% 25%,  rgba(125, 211, 252, 0.16), transparent),
            radial-gradient(circle 190px at 5%  40%,  rgba(110, 231, 183, 0.16), transparent),
            radial-gradient(circle 210px at 85% 45%,  rgba(249, 168, 212, 0.18), transparent),
            radial-gradient(circle 150px at 20% 58%,  rgba(251, 191, 36,  0.15), transparent),
            radial-gradient(circle 180px at 70% 63%,  rgba(196, 181, 253, 0.16), transparent),
            radial-gradient(circle 190px at 10% 75%,  rgba(167, 139, 250, 0.18), transparent),
            radial-gradient(circle 160px at 80% 80%,  rgba(110, 231, 183, 0.15), transparent),
            radial-gradient(circle 200px at 30% 88%,  rgba(249, 168, 212, 0.18), transparent),
            radial-gradient(circle 150px at 90% 94%,  rgba(253, 230, 138, 0.16), transparent),
            radial-gradient(circle 180px at 50% 100%, rgba(125, 211, 252, 0.15), transparent),
            var(--color-bg);
    }

    .post-header h1 {
        font-size: 1.75rem;
    }

    .content {
        padding: 2rem 1rem;
    }
}

/* Theme toggle */

.theme-toggle {
    display: inline;
}

.theme-toggle button {
    background: none;
    border: none;
    color: var(--color-accent);
    cursor: pointer;
    font-size: 0.85rem;
    font-family: var(--font-body);
    padding: 0;
    transition: color 0.2s ease;
}

.theme-toggle button:hover {
    color: var(--color-accent-hover);
}

/* Dark mode: auto (OS preference, unless user forced light) */

@media (prefers-color-scheme: dark) {
    :root:not(.theme-light) {
        --color-bg: #1a1a2e;
        --color-text: #e0e0e0;
        --color-text-light: #a0a0a0;
        --color-accent: #7eb8da;
        --color-accent-hover: #a8d4f0;
        --color-border: #3a3a4e;
        --color-code-bg: rgba(30, 30, 50, 0.85);
        --color-glass: rgba(26, 26, 46, 0.6);
        --color-glass-strong: rgba(26, 26, 46, 0.7);
        --color-blockquote-bg: rgba(30, 30, 50, 0.6);
        --color-th-bg: rgba(35, 35, 55, 0.85);
        --color-td-bg: rgba(26, 26, 46, 0.6);
    }

    :root:not(.theme-light) body {
        background:
            radial-gradient(circle 320px at 90% 5%,   rgba(167, 139, 250, 0.12), transparent),
            radial-gradient(circle 280px at 10% 12%,  rgba(196, 181, 253, 0.10), transparent),
            radial-gradient(circle 260px at 75% 22%,  rgba(125, 211, 252, 0.10), transparent),
            radial-gradient(circle 300px at 5%  38%,  rgba(110, 231, 183, 0.10), transparent),
            radial-gradient(circle 340px at 85% 42%,  rgba(249, 168, 212, 0.12), transparent),
            radial-gradient(circle 240px at 20% 55%,  rgba(251, 191, 36,  0.08), transparent),
            radial-gradient(circle 280px at 70% 60%,  rgba(196, 181, 253, 0.10), transparent),
            radial-gradient(circle 300px at 10% 72%,  rgba(167, 139, 250, 0.10), transparent),
            radial-gradient(circle 260px at 80% 78%,  rgba(110, 231, 183, 0.08), transparent),
            radial-gradient(circle 320px at 30% 85%,  rgba(249, 168, 212, 0.10), transparent),
            radial-gradient(circle 240px at 90% 92%,  rgba(253, 230, 138, 0.08), transparent),
            radial-gradient(circle 280px at 50% 98%,  rgba(125, 211, 252, 0.08), transparent),
            var(--color-bg);
        background-attachment: fixed;
    }
}

/* Dark mode: forced via toggle */

:root.theme-dark {
    --color-bg: #1a1a2e;
    --color-text: #e0e0e0;
    --color-text-light: #a0a0a0;
    --color-accent: #7eb8da;
    --color-accent-hover: #a8d4f0;
    --color-border: #3a3a4e;
    --color-code-bg: rgba(30, 30, 50, 0.85);
    --color-glass: rgba(26, 26, 46, 0.6);
    --color-glass-strong: rgba(26, 26, 46, 0.7);
    --color-blockquote-bg: rgba(30, 30, 50, 0.6);
    --color-th-bg: rgba(35, 35, 55, 0.85);
    --color-td-bg: rgba(26, 26, 46, 0.6);
}

:root.theme-dark body {
    background:
        radial-gradient(circle 320px at 90% 5%,   rgba(167, 139, 250, 0.12), transparent),
        radial-gradient(circle 280px at 10% 12%,  rgba(196, 181, 253, 0.10), transparent),
        radial-gradient(circle 260px at 75% 22%,  rgba(125, 211, 252, 0.10), transparent),
        radial-gradient(circle 300px at 5%  38%,  rgba(110, 231, 183, 0.10), transparent),
        radial-gradient(circle 340px at 85% 42%,  rgba(249, 168, 212, 0.12), transparent),
        radial-gradient(circle 240px at 20% 55%,  rgba(251, 191, 36,  0.08), transparent),
        radial-gradient(circle 280px at 70% 60%,  rgba(196, 181, 253, 0.10), transparent),
        radial-gradient(circle 300px at 10% 72%,  rgba(167, 139, 250, 0.10), transparent),
        radial-gradient(circle 260px at 80% 78%,  rgba(110, 231, 183, 0.08), transparent),
        radial-gradient(circle 320px at 30% 85%,  rgba(249, 168, 212, 0.10), transparent),
        radial-gradient(circle 240px at 90% 92%,  rgba(253, 230, 138, 0.08), transparent),
        radial-gradient(circle 280px at 50% 98%,  rgba(125, 211, 252, 0.08), transparent),
        var(--color-bg);
    background-attachment: fixed;
}

/* Dark mode: mobile overrides */

@media (max-width: 600px) and (prefers-color-scheme: dark) {
    :root:not(.theme-light) body {
        background:
            radial-gradient(circle 200px at 90% 5%,   rgba(167, 139, 250, 0.08), transparent),
            radial-gradient(circle 180px at 10% 15%,  rgba(196, 181, 253, 0.06), transparent),
            radial-gradient(circle 160px at 75% 25%,  rgba(125, 211, 252, 0.06), transparent),
            radial-gradient(circle 190px at 5%  40%,  rgba(110, 231, 183, 0.06), transparent),
            radial-gradient(circle 210px at 85% 45%,  rgba(249, 168, 212, 0.06), transparent),
            radial-gradient(circle 150px at 20% 58%,  rgba(251, 191, 36,  0.05), transparent),
            radial-gradient(circle 180px at 70% 63%,  rgba(196, 181, 253, 0.06), transparent),
            radial-gradient(circle 190px at 10% 75%,  rgba(167, 139, 250, 0.06), transparent),
            radial-gradient(circle 160px at 80% 80%,  rgba(110, 231, 183, 0.05), transparent),
            radial-gradient(circle 200px at 30% 88%,  rgba(249, 168, 212, 0.06), transparent),
            radial-gradient(circle 150px at 90% 94%,  rgba(253, 230, 138, 0.05), transparent),
            radial-gradient(circle 180px at 50% 100%, rgba(125, 211, 252, 0.05), transparent),
            var(--color-bg);
    }
}

@media (max-width: 600px) {
    :root.theme-dark body {
        background:
            radial-gradient(circle 200px at 90% 5%,   rgba(167, 139, 250, 0.08), transparent),
            radial-gradient(circle 180px at 10% 15%,  rgba(196, 181, 253, 0.06), transparent),
            radial-gradient(circle 160px at 75% 25%,  rgba(125, 211, 252, 0.06), transparent),
            radial-gradient(circle 190px at 5%  40%,  rgba(110, 231, 183, 0.06), transparent),
            radial-gradient(circle 210px at 85% 45%,  rgba(249, 168, 212, 0.06), transparent),
            radial-gradient(circle 150px at 20% 58%,  rgba(251, 191, 36,  0.05), transparent),
            radial-gradient(circle 180px at 70% 63%,  rgba(196, 181, 253, 0.06), transparent),
            radial-gradient(circle 190px at 10% 75%,  rgba(167, 139, 250, 0.06), transparent),
            radial-gradient(circle 160px at 80% 80%,  rgba(110, 231, 183, 0.05), transparent),
            radial-gradient(circle 200px at 30% 88%,  rgba(249, 168, 212, 0.06), transparent),
            radial-gradient(circle 150px at 90% 94%,  rgba(253, 230, 138, 0.05), transparent),
            radial-gradient(circle 180px at 50% 100%, rgba(125, 211, 252, 0.05), transparent),
            var(--color-bg);
    }
}