:root {
    --bg-color: #14181a;             /* Deepest everforest dark background */
    --text-color: #d3c6aa;           /* Warm everforest cream text */
    --accent-color: #8da874;         /* Rich everforest leaf-green accent */
    --secondary-color: rgba(28, 34, 37, 0.8); /* Darker translucent everforest base */
    --border-color: rgba(79, 92, 94, 0.35);  /* Subtle everforest sage green border */
    --card-bg: rgba(28, 34, 37, 0.7);  /* Darker translucent card bg */
    --glass-border: rgba(141, 168, 116, 0.15); /* Leaf-green tinted glass border */
    --font-main: 'Outfit', system-ui, -apple-system, sans-serif;
    --font-body: 'Lora', Georgia, serif;
    --font-code: 'JetBrains Mono', 'Fira Code', monospace;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-main);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Scrollbars */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: #21262d;
    border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
    background: #30363d;
}

/* Typography */
h1, h2, h3, h4 {
    margin-bottom: 1.5rem;
    color: var(--accent-color);
    font-weight: 700;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: opacity 0.2s;
}

a:hover {
    opacity: 0.8;
}

/* App Layout */
.app-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 290px;
    background-color: var(--secondary-color);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    height: 100vh;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: transform 0.3s ease;
}

.sidebar-header {
    padding: 1.5rem 1.25rem 1rem;
}

.sidebar-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.brand-icon {
    font-size: 1.5rem;
}

.brand-text {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-color);
    background: linear-gradient(90deg, var(--accent-color), #7fbbb3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.sidebar-search {
    padding: 0 1.25rem 1.25rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-search input {
    width: 100%;
    padding: 0.55rem 0.75rem;
    background-color: #2d353b;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    font-family: var(--font-main);
    font-size: 0.85rem;
    outline: none;
    transition: border-color 0.2s;
}

.sidebar-search input:focus {
    border-color: var(--accent-color);
}

.file-tree {
    flex-grow: 1;
    overflow-y: auto;
    padding: 1rem 0.5rem;
}

.tree-list {
    list-style: none;
    padding-left: 1rem;
}

.file-tree > .tree-list {
    padding-left: 0;
}

.tree-item {
    margin: 0.15rem 0;
}

.folder-header, .file-title-link {
    display: flex;
    align-items: center;
    padding: 0.35rem 0.5rem;
    border-radius: 6px;
    color: var(--text-color);
    cursor: pointer;
    font-size: 0.88rem;
    transition: background-color 0.15s, color 0.15s;
    user-select: none;
}

.folder-header:hover, .file-title-link:hover {
    background-color: #2d353b;
    color: var(--accent-color);
}

.toggle-arrow {
    display: inline-block;
    width: 1rem;
    font-size: 0.65rem;
    color: #8b949e;
}

.folder-icon, .file-icon {
    margin-right: 0.4rem;
}

.folder-title, .file-title-link {
    text-decoration: none;
    color: inherit;
    flex-grow: 1;
}

.file-title-link {
    display: flex;
}

.file-title-link.active, .folder-title.active {
    background-color: rgba(167, 192, 128, 0.18);
    color: var(--accent-color);
    font-weight: 500;
}

.folder-content {
    border-left: 1px solid var(--border-color);
    margin-left: 0.45rem;
}

/* Main Area */
.main-area {
    flex-grow: 1;
    min-width: 0;
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow-y: auto;
}

header.site-header {
    padding: 1.5rem 3rem 1rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
}

.site-title-link {
    text-decoration: none;
    color: inherit;
}

header.site-header h1 {
    font-size: 1.5rem;
    margin-bottom: 0;
    background: linear-gradient(90deg, var(--accent-color), #7fbbb3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.sidebar-toggle {
    display: none;
    background: #2d353b;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    font-size: 1.1rem;
    padding: 0.4rem 0.75rem;
    cursor: pointer;
    margin-right: 1rem;
    outline: none;
    transition: background-color 0.2s;
}

.sidebar-toggle:hover {
    background-color: #3d484d;
}

.content-wrapper {
    padding: 3rem;
    flex-grow: 1;
    max-width: 960px;
    width: 100%;
    margin: 0 auto;
}

/* Grid layout for landing */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 1.25rem;
}

.card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    padding: 1rem 1.25rem;
    border-radius: 8px;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: transform 0.2s, border-color 0.2s;
    text-decoration: none;
    cursor: pointer;
}

.card:hover {
    transform: translateY(-2px);
    border-color: var(--accent-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.card-icon {
    font-size: 1.5rem;
}

.card-info {
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.card-info h3 {
    margin-bottom: 0.1rem;
    font-size: 1.05rem;
    color: var(--text-color);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.card-meta {
    font-size: 0.78rem;
    color: #85928f;
}

/* Post Content & Markdown Body */
.post-content {
    background: transparent;
}

.markdown-body {
    font-family: var(--font-body);
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-color); /* warm everforest foreground */
}

.markdown-body h1, 
.markdown-body h2, 
.markdown-body h3, 
.markdown-body h4 {
    font-family: var(--font-main);
    color: var(--text-color);
    margin-top: 2.2rem;
    margin-bottom: 1.1rem;
    font-weight: 600;
    line-height: 1.3;
}

.markdown-body h1 {
    font-size: 2.1rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.markdown-body h2 {
    font-size: 1.65rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.35rem;
}

.markdown-body h3 {
    font-size: 1.35rem;
}

.markdown-body p {
    margin-bottom: 1.5rem;
}

.markdown-body ul, 
.markdown-body ol {
    margin-bottom: 1.5rem;
    padding-left: 1.75rem;
}

.markdown-body li {
    margin-bottom: 0.5rem;
}

.markdown-body blockquote {
    border-left: 4px solid var(--accent-color);
    padding: 0.6rem 1.25rem;
    margin: 1.75rem 0;
    background-color: rgba(167, 192, 128, 0.05); /* warm green translucent tint */
    color: #85928f; /* everforest muted green */
    font-style: italic;
    border-radius: 0 8px 8px 0;
}

.markdown-body blockquote p {
    margin-bottom: 0;
}

.markdown-body a {
    color: var(--accent-color);
    text-decoration: underline;
    text-underline-offset: 4px;
    transition: color 0.15s ease;
}

.markdown-body a:hover {
    color: #7fbbb3; /* everforest light blue-green */
    opacity: 1;
}

.post-content img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
    margin: 2rem auto;
    box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    display: block;
    border: 1px solid var(--border-color);
}

/* Code Blocks */
pre {
    background: #232a2e !important; /* matches everforest dark bg */
    padding: 1.25rem;
    border-radius: 8px;
    overflow-x: auto;
    margin: 1.75rem 0;
    border: 1px solid var(--border-color);
}

code {
    font-family: var(--font-code);
    font-size: 0.9rem;
}

p > code {
    background-color: #2d353b;
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    color: #e67e80; /* everforest warm red/orange */
    font-family: var(--font-code);
}

/* LaTeX */
.katex-display {
    margin: 1.5rem 0;
    overflow-x: auto;
    overflow-y: hidden;
}

/* Sidebar Overlay */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 999;
}

/* Responsive */
@media (max-width: 850px) {
    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        transform: translateX(-100%);
        box-shadow: 5px 0 25px rgba(0,0,0,0.6);
        z-index: 1000;
    }
    .sidebar.active {
        transform: translateX(0);
    }
    .sidebar.active ~ .sidebar-overlay {
        display: block;
    }
    .sidebar-toggle {
        display: inline-block;
    }
    header.site-header {
        padding: 0.5rem 0.75rem;
    }
    .site-title-link h1 {
        font-size: 1.1rem !important;
    }
    .content-wrapper {
        padding: 0.75rem;
    }
    
    /* Ultra-compact typography & code size for mobile view */
    .markdown-body {
        font-size: 0.88rem;   /* scaled down for high information density */
        line-height: 1.55;    /* tighter line height */
    }
    .markdown-body h1 {
        font-size: 1.35rem;   /* smaller mobile headings */
        margin-top: 1.25rem;
        margin-bottom: 0.5rem;
    }
    .markdown-body h2 {
        font-size: 1.18rem;
        margin-top: 1.1rem;
        margin-bottom: 0.4rem;
    }
    .markdown-body h3 {
        font-size: 1.05rem;
        margin-top: 0.95rem;
    }
    .markdown-body p, .markdown-body ul, .markdown-body ol {
        margin-bottom: 0.75rem;
    }
    blockquote {
        margin: 1rem 0;
        padding: 0.4rem 0.75rem;
    }
    pre {
        padding: 0.65rem 0.85rem;
        margin: 1rem 0;
    }
    pre code, p > code {
        font-size: 0.78rem !important; /* significantly smaller code font */
    }
    
    /* Smaller folder/note cards on mobile */
    .grid {
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
        gap: 0.75rem;
    }
    .card {
        padding: 0.75rem 1rem;
        gap: 0.5rem;
    }
    .card-icon {
        font-size: 1.2rem;
    }
    .card-info h3 {
        font-size: 0.92rem;
    }
    .card-meta {
        font-size: 0.72rem;
    }
}