/* ===== Fonts ===== */
@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Roboto+Slab:wght@500;700&family=JetBrains+Mono:wght@400;500&display=swap");

/* ===== CSS Variables ===== */
:root {
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Roboto Slab', serif;
    --font-mono: 'JetBrains Mono', 'Cascadia Code', 'Fira Code', monospace;
    --transition-speed: 0.3s;
    --border-radius: 10px;
    --border-radius-sm: 6px;
}

/* ===== Theme: Light ===== */
body[data-theme="light"] {
    --bg-color: #f5f6f8;
    --color: #1a1a2e;
    --color-secondary: #555;
    --link-color: #2563eb;
    --link-hover-color: #1d4ed8;
    --section-bg-color: #ffffff;
    --section-border-color: #e2e8f0;
    --heading-color: #1e293b;
    --heading-underline-color: #cbd5e1;
    --heading-hash-color: #94a3b8;
    --code-box-bg-color: #f1f5f9;
    --code-box-color: #0f766e;
    --code-box-border-color: #e2e8f0;
    --code-box-color-ex: #dc2626;
    --inline-code-bg: #f1f5f9;
    --inline-code-color: #0f766e;
    --block-quote-bg-color: #f8fafc;
    --block-quote-color: #475569;
    --block-quote-border-color: #e2e8f0;
    --block-quote-border-left-color: #3b82f6;
    --table-header-bg: #f1f5f9;
    --table-border-color: #e2e8f0;
    --table-stripe-bg: #f8fafc;
    --table-hover-bg: #e2e8f0;
    --top-bar-bg: rgba(245, 246, 248, 0.85);
    --copy-btn-bg: #e2e8f0;
    --copy-btn-color: #475569;
    --copy-btn-hover-bg: #cbd5e1;
    --toc-bg: #f8fafc;
    --toc-border: #e2e8f0;
    --toc-link-color: #2563eb;
    --toc-link-hover-bg: #e2e8f0;
    --scrollbar-track: #f1f5f9;
    --scrollbar-thumb: #cbd5e1;
    --bs-body-bg: #f5f6f8;
    --bs-emphasis-color: #1a1a2e;
    --bs-border-color: #e2e8f0;
}

/* ===== Theme: Dark ===== */
body[data-theme="dark"] {
    --bg-color: #0d1117;
    --color: #e6edf3;
    --color-secondary: #8b949e;
    --link-color: #58a6ff;
    --link-hover-color: #79c0ff;
    --section-bg-color: #161b22;
    --section-border-color: #30363d;
    --heading-color: #e6edf3;
    --heading-underline-color: #30363d;
    --heading-hash-color: #484f58;
    --code-box-bg-color: #0d1117;
    --code-box-color: #7ee787;
    --code-box-border-color: #30363d;
    --code-box-color-ex: #ffa657;
    --inline-code-bg: rgba(110, 118, 129, 0.2);
    --inline-code-color: #7ee787;
    --block-quote-bg-color: #161b22;
    --block-quote-color: #8b949e;
    --block-quote-border-color: #30363d;
    --block-quote-border-left-color: #58a6ff;
    --table-header-bg: #1c2128;
    --table-border-color: #30363d;
    --table-stripe-bg: rgba(22, 27, 34, 0.5);
    --table-hover-bg: #1c2128;
    --top-bar-bg: rgba(13, 17, 23, 0.85);
    --copy-btn-bg: #30363d;
    --copy-btn-color: #8b949e;
    --copy-btn-hover-bg: #484f58;
    --toc-bg: #161b22;
    --toc-border: #30363d;
    --toc-link-color: #58a6ff;
    --toc-link-hover-bg: #1c2128;
    --scrollbar-track: #0d1117;
    --scrollbar-thumb: #30363d;
    --bs-body-bg: #0d1117;
    --bs-emphasis-color: #e6edf3;
    --bs-border-color: #30363d;
}

/* ===== Base ===== */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 60px;
}

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.65;
    background-color: var(--bg-color);
    color: var(--color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--copy-btn-hover-bg);
}

.top-bar {
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 10px;
    background: var(--top-bar-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--section-border-color);
    margin: 0 -12px;
    padding-left: 12px;
    padding-right: 12px;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--color-secondary);
    transition: color var(--transition-speed);
}

.back-link:hover {
    color: var(--link-color);
}

.back-link i {
    font-size: 0.95rem;
}

.button {
    cursor: pointer;
    font-size: 1.1rem;
    color: var(--color-secondary);
    transition: color var(--transition-speed), transform var(--transition-speed);
    padding: 2px;
    line-height: 1;
}

.button:hover {
    color: var(--link-color);
    transform: rotate(180deg);
}

/* ===== Page Title ===== */
.title {
    font-family: var(--font-heading);
    padding: 1.5rem 1rem 1rem;
    text-align: center;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--heading-color);
    letter-spacing: 0.5px;
}

/* ===== Section List (TOC) ===== */
.section-list {
    background: var(--toc-bg);
    border: 1px solid var(--toc-border);
    border-radius: var(--border-radius);
    padding: 1rem 1.25rem;
    margin-bottom: 1.25rem;
}

.section-list ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.section-list li {
    margin: 0;
}

.section-list a {
    display: inline-block;
    padding: 4px 12px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--toc-link-color);
    background: transparent;
    border: 1px solid var(--toc-border);
    border-radius: 20px;
    transition: all var(--transition-speed);
}

.section-list a:hover {
    background: var(--toc-link-hover-bg);
    border-color: var(--toc-link-color);
}

/* ===== Sections ===== */
.sections {
    margin-bottom: 1rem;
    padding: 1.25rem;
    background-color: var(--section-bg-color);
    border: 1px solid var(--section-border-color);
    border-radius: var(--border-radius);
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

/* ===== Section Headings ===== */
.heading {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--heading-color);
    padding-bottom: 8px;
    margin-bottom: 12px;
    border-bottom: 2px solid var(--heading-underline-color);
}

.heading::before {
    content: "# ";
    color: var(--heading-hash-color);
    font-weight: 500;
}

.sections ol,
.sections ul {
    padding-left: 1.25rem;
}

/* ===== Paragraphs ===== */
p {
    margin-bottom: 0.5rem;
    text-align: justify;
    color: var(--color);
}

/* ===== Code: Inline ===== */
code {
    font-family: var(--font-mono);
    font-size: 0.875em;
    padding: 2px 6px;
    border-radius: 4px;
    background-color: var(--inline-code-bg);
    color: var(--inline-code-color);
}

/* ===== Code: Block (full-width) ===== */
.code-box {
    position: relative;
    margin-bottom: 12px;
    padding: 12px 14px;
    border: 1px solid var(--code-box-border-color);
    border-left: 3px solid var(--link-color);
    border-radius: var(--border-radius-sm);
    line-height: 1.5;
    background-color: var(--code-box-bg-color);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    overflow-x: auto;
    transition: background-color var(--transition-speed), border-color var(--transition-speed);
}

.code-box code {
    display: block;
    padding: 0;
    background: none;
    color: var(--code-box-color);
    font-size: inherit;
    white-space: pre;
}

.code-box-color code,
.code-box-color {
    color: var(--code-box-color-ex);
}

/* ===== Copy Button ===== */
.copy-btn {
    position: absolute;
    top: 6px;
    right: 6px;
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 10px;
    font-family: var(--font-body);
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--copy-btn-color);
    background: var(--copy-btn-bg);
    border: 1px solid var(--section-border-color);
    border-radius: 4px;
    cursor: pointer;
    opacity: 0;
    transition: opacity var(--transition-speed), background var(--transition-speed), color var(--transition-speed);
    z-index: 2;
    line-height: 1;
}

.code-box:hover .copy-btn {
    opacity: 1;
}

.copy-btn:hover {
    background: var(--copy-btn-hover-bg);
    color: var(--color);
}

.copy-btn.copied {
    color: var(--code-box-color);
    opacity: 1;
}

/* ===== Blockquote ===== */
.block-quote {
    margin-bottom: 10px;
    padding: 10px 14px;
    border: 1px solid var(--block-quote-border-color);
    border-left: 4px solid var(--block-quote-border-left-color);
    border-radius: var(--border-radius-sm);
    background-color: var(--block-quote-bg-color);
    color: var(--block-quote-color);
    word-spacing: 3px;
    font-size: 0.95rem;
    transition: all var(--transition-speed);
}

/* ===== Tables ===== */
.table-responsive {
    margin-bottom: 8px;
}

.table {
    --bs-table-bg: transparent;
    --bs-table-color: var(--color);
    --bs-table-border-color: var(--table-border-color);
    --bs-table-striped-bg: var(--table-stripe-bg);
    --bs-table-striped-color: var(--color);
    --bs-table-hover-bg: var(--table-hover-bg);
    --bs-table-hover-color: var(--color);
    font-size: 0.9rem;
    margin-bottom: 0;
}

.table thead {
    text-align: center;
}

.table thead th {
    background-color: var(--table-header-bg);
    color: var(--heading-color);
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    padding: 10px 12px;
    border-bottom: 2px solid var(--table-border-color);
    white-space: nowrap;
}

.table td {
    padding: 8px 12px;
    vertical-align: middle;
    border-color: var(--table-border-color);
}

.table code {
    white-space: nowrap;
}

.table-bordered {
    border-color: var(--table-border-color);
}

.table-striped>tbody>tr:nth-of-type(odd)>* {
    --bs-table-bg-type: var(--table-stripe-bg);
}

/* ===== Sub-headings inside sections ===== */
.sections h5 {
    font-size: 1rem;
    font-weight: 600;
    margin-top: 10px;
    margin-bottom: 6px;
    color: var(--heading-color);
}

.sections h6 {
    font-size: 0.9rem;
    font-weight: 600;
    margin-top: 8px;
    margin-bottom: 4px;
    color: var(--color-secondary);
}

/* ===== Images ===== */
.img {
    height: 100%;
    width: 100%;
    border-radius: var(--border-radius-sm);
}

/* ===== Justify class ===== */
.justify {
    padding-bottom: 6px;
    text-align: justify;
}

/* ===== Note/strong styling ===== */
.sections strong {
    color: var(--heading-color);
}

/* ===== Bottom Navigation ===== */
nav {
    position: sticky;
    bottom: 0;
    padding: 5px 10px;
    font-size: 1.15rem;
    display: flex;
    justify-content: space-between;
    background: var(--top-bar-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-top: 1px solid var(--section-border-color);
    margin: 0 -12px;
    padding-left: 12px;
    padding-right: 12px;
}

nav a {
    color: var(--color-secondary);
    transition: color var(--transition-speed), transform var(--transition-speed);
}

nav a:hover {
    color: var(--link-color);
    transform: scale(1.1);
}

/* ===== Responsiveness ===== */
@media screen and (max-width: 575px) {
    .container {
        padding: 5px;
    }

    .title {
        font-size: 1.4rem;
        padding: 1rem 0.5rem 0.5rem;
    }

    .section-list {
        padding: 0.75rem;
    }

    .section-list a {
        font-size: 0.8rem;
        padding: 3px 10px;
    }

    .sections {
        padding: 12px 10px;
        font-size: 0.9rem;
    }

    .heading {
        font-size: 1.05rem;
    }

    .code-box {
        font-size: 0.8rem;
        padding: 10px;
    }

    .table {
        font-size: 0.8rem;
    }

    .top-bar {
        padding: 4px 8px;
        margin: 0 -5px;
    }

    nav {
        margin: 0 -5px;
        padding: 4px 8px;
    }

    .copy-btn {
        opacity: 1;
    }
}

@media screen and (max-width: 380px) {
    .section-list ul {
        gap: 4px;
    }

    .section-list a {
        font-size: 0.75rem;
        padding: 2px 8px;
    }
}