/* ========================================
   svdu Theme
   ======================================== */

/* --- CSS Custom Properties --- */
:root {
    --color-bg: #fafaf9;
    --color-surface: #ffffff;
    --color-text: #1c1c1c;
    --color-text-muted: #6b6b6b;
    --color-border: #e5e5e0;
    --color-accent: #1c1c1c;
    --color-tag: #787774;
    --color-tag-bg: #f0f0eb;

    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
    --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;

    --layout-width: 1000px;
    --sidebar-width: 200px;

    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 5rem;

    --radius-sm: 4px;
    --radius-md: 8px;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --color-bg: #1a1a18;
        --color-surface: #252523;
        --color-text: #e5e5e0;
        --color-text-muted: #989890;
        --color-border: #333330;
        --color-accent: #e5e5e0;
        --color-tag: #989890;
        --color-tag-bg: #2a2a28;
    }
}
:root[data-theme="dark"] {
    --color-bg: #1a1a18;
    --color-surface: #252523;
    --color-text: #e5e5e0;
    --color-text-muted: #989890;
    --color-border: #333330;
    --color-accent: #e5e5e0;
    --color-tag: #989890;
    --color-tag-bg: #2a2a28;
}

/* --- Reset & Base --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-sans);
    color: var(--color-text);
    background: var(--color-bg);
    line-height: 1.7;
    min-height: 100vh;
}

a { color: inherit; text-decoration: none; }
a:hover { opacity: 0.7; }
img { max-width: 100%; height: auto; display: block; }

/* --- Layout --- */
.layout {
    max-width: var(--layout-width);
    margin: 0 auto;
    padding: var(--spacing-2xl) var(--spacing-md);
    display: flex;
    gap: var(--spacing-md);
    align-items: flex-start;
}

/* --- Sidebar --- */
.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    position: sticky;
    top: var(--spacing-2xl);
}

.site-name {
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    display: block;
    margin-bottom: var(--spacing-xs);
}

.site-desc { font-size: 0.8rem; color: var(--color-text-muted); margin-bottom: var(--spacing-xs); }
.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--color-text);
    cursor: pointer;
    padding: 4px;
    align-items: center;
    justify-content: center;
}


.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-lg);
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

.sidebar-nav a {
    display: block;
    padding: 0.15rem 0;
    transition: color 0.15s;
    border-left: 2px solid transparent;
    margin-left: -8px; padding-left: 6px;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
    color: var(--color-text);
    opacity: 1;
}

.sidebar-nav a.active {
    border-left-color: var(--color-text);
}

.sidebar-copy { font-size: 0.7rem; color: var(--color-text-muted); margin-top: var(--spacing-lg); display: flex; justify-content: space-between; align-items: center; }
.theme-toggle { background: none; border: none; color: var(--color-text-muted); cursor: pointer; padding: 2px; display: flex; align-items: center; transition: color 0.15s; }
.theme-toggle:hover { color: var(--color-text); }
.theme-icon { display: none; }
:root:not([data-theme="dark"]) .theme-icon-sun { display: block; }
:root[data-theme="dark"] .theme-icon-moon { display: block; }
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-icon-sun { display: none; }
    :root:not([data-theme="light"]) .theme-icon-moon { display: block; }
}

/* --- Content Area --- */
.content {
    max-width: 768px;
    flex: 1;
    min-width: 0;
    padding-left: 48px;
    padding-right: 48px;
}

/* --- Footer --- */
.site-footer {
    max-width: var(--layout-width);
    margin: 0 auto;
    padding: var(--spacing-lg) var(--spacing-md);
    color: var(--color-text-muted);
    font-size: 0.8rem;
}

.footer-inner {
    padding-left: calc(var(--sidebar-width) + var(--spacing-lg));
}

/* --- Typography --- */
.fmt {
    font-size: 0.95rem;
    line-height: 1.85;
    word-break: break-word;
}
.fmt h2 { font-size: 1.25rem; margin-top: var(--spacing-xl); margin-bottom: var(--spacing-md); font-weight: 600; }
.fmt h3 { font-size: 1.05rem; margin-top: var(--spacing-lg); margin-bottom: var(--spacing-sm); font-weight: 600; }
.fmt p { margin-bottom: var(--spacing-md); }
.fmt ul, .fmt ol { margin-bottom: var(--spacing-md); padding-left: 1.5rem; }
.fmt li { margin-bottom: var(--spacing-xs); }
.fmt blockquote {
    border-left: 3px solid var(--color-border);
    padding-left: var(--spacing-md);
    margin: var(--spacing-lg) 0;
    color: var(--color-text-muted);
}
.fmt code {
    font-size: 0.85em;
    background: var(--color-tag-bg);
    padding: 0.15em 0.4em;
    border-radius: var(--radius-sm);
}
.fmt pre {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    overflow-x: auto;
    margin-bottom: var(--spacing-lg);
}
.fmt pre code { background: none; padding: 0; font-size: 0.8rem; line-height: 1.6; }
.fmt img { margin: var(--spacing-lg) auto; }
.fmt hr { border: none; border-top: 1px solid var(--color-border); margin: var(--spacing-xl) 0; }

/* ========================================
   Home Page
   ======================================== */
.home-posts { padding-bottom: var(--spacing-lg); }
.home-posts-heading { font-size: 0.8rem; font-weight: 600; color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: var(--spacing-sm); }
.home-posts-list { list-style: none; display: flex; flex-direction: column; gap: var(--spacing-sm); }
.home-post-item {
    display: flex; justify-content: space-between; align-items: baseline;
    font-size: 0.9rem;
}
.home-post-item a { min-width: 0; flex: 1; }
.home-post-date {
    font-size: 0.8rem; color: var(--color-text-muted);
    flex-shrink: 0; margin-left: var(--spacing-md);
    font-family: var(--font-mono);
}
.home-posts-more {
    display: inline-block; margin-top: var(--spacing-sm);
    font-size: 0.85rem; color: var(--color-text-muted);
    transition: color 0.15s;
}
.home-posts-more:hover { color: var(--color-text); opacity: 1; }

.home-photos { padding-bottom: var(--spacing-xl); }
.home-slider { position: relative; overflow: hidden; }
.home-slider-track { position: relative; height: 60vh; max-height: 550px; }
.home-slider-slide {
    position: absolute; inset: 0; overflow: hidden;
    display: block; cursor: pointer;
    opacity: 0; transition: opacity 0.8s ease;
    z-index: 0;
}
.home-slider-slide.active { opacity: 1; z-index: 1; }
.home-slider-slide img { width: 100%; height: 100%; object-fit: contain; display: block; }
.home-slider-prev, .home-slider-next {
    position: absolute; top: 50%; transform: translateY(-50%); z-index: 2;
    width: 40px; height: 40px;
    background: none; border: none;
    color: #1c1c1c; font-size: 1.5rem; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    opacity: 0; transition: opacity 0.2s;
    text-shadow: 0 0 12px rgba(255,255,255,0.9);
}
.home-slider:hover .home-slider-prev,
.home-slider:hover .home-slider-next { opacity: 1; }
.home-slider-prev { left: var(--spacing-md); }
.home-slider-next { right: var(--spacing-md); }

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .home-slider-prev,
    :root:not([data-theme="light"]) .home-slider-next { color: #fff; text-shadow: 0 0 12px rgba(0,0,0,0.8); }
}
:root[data-theme="dark"] .home-slider-prev,
:root[data-theme="dark"] .home-slider-next { color: #fff; text-shadow: 0 0 12px rgba(0,0,0,0.8); }





/* ========================================
   Archive List (year-grouped)
   ======================================== */
.archive-page-title { font-size: 1.1rem; font-weight: 700; margin-bottom: var(--spacing-lg); }
.page-article + .archive-list { margin-top: var(--spacing-lg); }
.archive-list { list-style: none; display: flex; flex-direction: column; gap: var(--spacing-sm); }
.archive-year {
    font-size: 0.8rem; font-weight: 600; color: var(--color-text-muted);
    margin-top: var(--spacing-md);
}
.archive-year:first-child { margin-top: 0; }
.archive-item { display: flex; justify-content: space-between; align-items: baseline; font-size: 0.9rem; }
.archive-item a { flex: 1; min-width: 0; }
.archive-date { font-size: 0.8rem; color: var(--color-text-muted); flex-shrink: 0; margin-left: var(--spacing-md); font-family: var(--font-mono); }

/* ========================================
   Single Post
   ======================================== */
.post-header { margin-bottom: var(--spacing-lg); }
.post-title { font-size: 1.3rem; font-weight: 700; letter-spacing: -0.02em; line-height: 1.3; margin-bottom: var(--spacing-xs); }
.post-meta { font-size: 0.8rem; color: var(--color-text-muted); display: flex; gap: var(--spacing-md); }
.post-content { margin-bottom: var(--spacing-lg); }
.post-tags { display: flex; flex-wrap: wrap; gap: var(--spacing-sm); margin-bottom: var(--spacing-lg); font-size: 0.75rem; }
.post-tags a {
    background: var(--color-tag-bg); color: var(--color-tag);
    padding: 0.2em 0.7em; border-radius: 999px;
    transition: color 0.15s, background 0.15s;
}
.post-tags a:hover { color: var(--color-text); opacity: 1; }
.post-near {
    display: flex; justify-content: space-between; padding: var(--spacing-md) 0;
    border-top: 1px solid var(--color-border); font-size: 0.8rem; color: var(--color-text-muted);
}
.post-near-prev, .post-near-next { max-width: 48%; }

/* ========================================
   Page
   ======================================== */
.page-header { margin-bottom: var(--spacing-lg); }
.page-title { font-size: 1.3rem; font-weight: 700; letter-spacing: -0.02em; }

/* ========================================
   Photography Project
   ======================================== */
.photo-header { scroll-snap-align: start; margin-bottom: var(--spacing-md); }
.photo-title { font-size: 1.3rem; font-weight: 700; }
.photo-date { font-size: 0.8rem; color: var(--color-text-muted); margin-top: var(--spacing-xs); }
.photo-content { margin-bottom: var(--spacing-lg); }
.photo-grid { display: flex; flex-direction: column; }
.photo-item { scroll-snap-align: start; display: flex; align-items: center; justify-content: flex-start; padding: var(--spacing-md) 0; contain: layout paint; scroll-margin-top: var(--spacing-lg); }
.photo-item img { max-height: 85vh; max-width: 100%; width: auto; object-fit: contain; cursor: zoom-in; }
.lazy-img { opacity: 0; transition: opacity 0.3s; }
.lazy-img.loaded { opacity: 1; }

/* ========================================
   Subpage Grid
   ======================================== */
.subpage-grid-title { font-size: 1.3rem; font-weight: 700; margin-bottom: var(--spacing-lg); }
.subpage-grid { margin-top: var(--spacing-lg); }
.subpage-grid-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--spacing-md); }
.subpage-grid-card { display: block; transition: opacity 0.2s; }
.subpage-grid-card:hover { opacity: 1; }
.subpage-grid-thumb { aspect-ratio: 4 / 3; overflow: hidden; background: var(--color-tag-bg); }
.subpage-grid-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.3s; }
.subpage-grid-card:hover .subpage-grid-thumb img { transform: scale(1.02); }
.subpage-grid-info { padding: var(--spacing-xs) 0; }
.subpage-grid-info h3 { font-size: 0.85rem; font-weight: 600; line-height: 1.4; }
.subpage-grid-empty { text-align: center; color: var(--color-text-muted); padding: var(--spacing-xl) 0; }

@media (max-width: 640px) {
    .subpage-grid-grid { grid-template-columns: 1fr; }
}
@media (min-width: 641px) and (max-width: 900px) {
    .subpage-grid-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ========================================
   404
   ======================================== */
.error-main { padding: var(--spacing-xl) 0; text-align: center; }
.error-title { font-size: 4rem; font-weight: 700; letter-spacing: -0.04em; line-height: 1; margin-bottom: var(--spacing-sm); }
.error-subtitle { font-size: 1rem; color: var(--color-text-muted); margin-bottom: var(--spacing-md); }
.error-home-link { font-size: 0.9rem; color: var(--color-text-muted); }
.error-home-link:hover { color: var(--color-text); }

/* ========================================
   Photo Stream
   ======================================== */
.photo-stream {
    --row-h: 200px;
    display: flex;
    flex-flow: wrap;
    align-items: stretch;
    gap: 4px;
    height: auto;
    overflow: visible;
    margin-top: var(--spacing-lg);
}
.photo-stream::after {
    content: "";
    flex-grow: 999999;
}
.photo-stream-item {
    height: var(--row-h);
    flex: var(--ar) 1 calc(var(--row-h) * var(--ar));
    overflow: hidden;
    display: block;
    scroll-margin-top: var(--spacing-lg);
}
.photo-stream-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}
@media (max-width: 640px) {
    .photo-stream { --row-h: 140px; }
}

/* ========================================
   Lightbox
   ======================================== */
.menu-panel { display: none; }

.lightbox-overlay {
    position: fixed; inset: 0; z-index: 9999;
    background: #ffffff;
    display: flex; align-items: center; justify-content: center;
    opacity: 0; visibility: hidden;
    transition: opacity 0.2s, visibility 0.2s;
}
.lightbox-overlay.open { opacity: 1; visibility: visible; }
.lightbox-img { max-width: 90vw; max-height: 85vh; object-fit: contain; cursor: zoom-out; }
.lightbox-close {
    position: absolute; top: var(--spacing-lg); right: var(--spacing-lg);
    width: 40px; height: 40px; background: none; border: none;
    color: #1c1c1c; font-size: 1.5rem; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    opacity: 0.7; transition: opacity 0.15s;
}
.lightbox-close:hover { opacity: 1; }
.lightbox-prev, .lightbox-next {
    position: absolute; top: 50%; transform: translateY(-50%);
    width: 48px; height: 48px;
    background: rgba(0,0,0,0.05); border: none; border-radius: 50%;
    color: #1c1c1c; font-size: 1.2rem; cursor: pointer;
    display: flex; align-items: center; justify-content: center;
    opacity: 0.6; transition: opacity 0.15s;
}
.lightbox-prev { left: var(--spacing-lg); }
.lightbox-next { right: var(--spacing-lg); }
.lightbox-prev:hover, .lightbox-next:hover { opacity: 1; }

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .lightbox-overlay { background: #000000; }
    :root:not([data-theme="light"]) .lightbox-close,
    :root:not([data-theme="light"]) .lightbox-prev,
    :root:not([data-theme="light"]) .lightbox-next { color: #ffffff; }
    :root:not([data-theme="light"]) .lightbox-prev,
    :root:not([data-theme="light"]) .lightbox-next { background: rgba(255, 255, 255, 0.1); }
}
:root[data-theme="dark"] .lightbox-overlay { background: #000000; }
:root[data-theme="dark"] .lightbox-close,
:root[data-theme="dark"] .lightbox-prev,
:root[data-theme="dark"] .lightbox-next { color: #ffffff; }
:root[data-theme="dark"] .lightbox-prev,
:root[data-theme="dark"] .lightbox-next { background: rgba(255, 255, 255, 0.1); }

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 640px) {
    /* --- Root spacing --- */
    :root {
        --spacing-xl: 2rem;
        --spacing-2xl: 2.5rem;
    }

    /* --- Layout --- */
    .layout {
        flex-direction: column;
        padding: 0;
        gap: 0;
    }

    /* --- Sidebar → sticky top bar --- */
    .sidebar {
        width: 100%;
        position: sticky;
        top: 0;
        z-index: 100;
        background: var(--color-bg);
        padding: 0;
    }

    .sidebar-top {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: var(--spacing-sm) var(--spacing-md);
        min-height: 48px;
    }

    .site-name {
        margin-bottom: 0;
        font-size: 0.95rem;
    }

    .menu-toggle {
        display: flex;
        width: 40px;
        height: 40px;
        align-items: center;
        justify-content: center;
        border-radius: var(--radius-sm);
    }

    .menu-toggle:active {
        background: var(--color-tag-bg);
    }

    .site-desc {
        display: none;
    }

    .sidebar > .sidebar-nav {
        display: none;
    }

    .sidebar > .sidebar-copy {
        display: none;
    }

    /* --- Menu panel (overlay) --- */
    .menu-panel {
        display: block;
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        z-index: 99;
        background: rgba(0, 0, 0, 0.3);
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.25s;
    }

    .menu-panel.open {
        opacity: 1;
        pointer-events: auto;
    }

    .menu-panel-inner {
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        background: var(--color-bg);
        padding: var(--spacing-lg) var(--spacing-md);
        padding-top: calc(48px + var(--spacing-md));
        transform: translateY(-100%);
        transition: transform 0.25s ease;
    }

    .menu-panel.open .menu-panel-inner {
        transform: translateY(0);
    }

    .menu-panel .sidebar-nav {
        display: flex;
        flex-direction: column;
        gap: 0;
    }

    .menu-panel .sidebar-nav a {
        font-size: 1rem;
        padding: var(--spacing-md) 0;
        border-left: none;
        margin-left: 0;
        padding-left: 0;
        border-bottom: 1px solid var(--color-border);
    }

    .menu-panel .sidebar-nav a:last-child {
        border-bottom: none;
    }

    .menu-panel .sidebar-nav a.active {
        border-left: none;
        border-bottom-color: var(--color-text);
    }

    .menu-panel .sidebar-copy {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin-top: var(--spacing-lg);
        font-size: 0.75rem;
        color: var(--color-text-muted);
    }

    /* --- Content --- */
    .content {
        width: 100%;
        padding: var(--spacing-md);
    }

    /* --- Footer --- */
    .footer-inner {
        padding-left: 0;
    }

    /* --- Typography --- */
    .post-title,
    .page-title,
    .photo-title {
        font-size: 1.15rem;
    }

    .fmt {
        font-size: 0.9rem;
    }

    .fmt h2 {
        font-size: 1.1rem;
        margin-top: var(--spacing-lg);
    }

    .fmt h3 {
        font-size: 1rem;
    }

    .error-title {
        font-size: 3rem;
    }

    /* --- Post meta --- */
    .post-meta {
        flex-direction: column;
        gap: 2px;
    }

    /* --- Touch targets --- */
    .archive-item {
        min-height: 44px;
        align-items: center;
    }

    .archive-date {
        display: none;
    }

    .post-tags a {
        padding: 0.35em 0.8em;
    }

    .post-near a {
        padding: var(--spacing-md) 0;
        min-height: 44px;
        display: flex;
        align-items: center;
    }

    .lightbox-close {
        width: 48px;
        height: 48px;
        font-size: 1.8rem;
    }

    /* --- Slider buttons always visible on mobile --- */
    .home-slider-prev,
    .home-slider-next {
        opacity: 0.8;
    }

    /* --- Photo pages --- */
    .photo-item {
        padding: var(--spacing-lg) 0;
        scroll-margin-top: calc(48px + var(--spacing-md));
    }

    .photo-header {
        scroll-margin-top: calc(48px + var(--spacing-md));
    }

    /* --- Subpage grid --- */
    .subpage-grid-grid {
        gap: var(--spacing-sm);
    }

    /* --- Home --- */
    .home-slider-track { height: 40vh; }

    .home-posts {
        padding-bottom: var(--spacing-md);
    }

    .site-footer {
        padding: var(--spacing-md);
    }

    /* --- Post header --- */
    .post-header {
        text-align: left;
    }
}