/* ========================================================
   MTB Tech Blog — style.css
   ======================================================== */

/* ========= CSS Variables ========= */

:root {
    --color-bg:           #F8FAFC;
    --color-surface:      #FFFFFF;
    --color-border:       #E2E8F0;
    --color-text:         #0F172A;
    --color-text-muted:   #475569;
    --color-text-soft:    #64748B;
    --color-accent:       #22C55E;
    --color-accent-hover: #16A34A;

    --color-code-bg:      rgba(0, 0, 0, 0.06);
    --color-pre-bg:       #0F172A;
    --color-pre-text:     #E2E8F0;
    --color-pre-border:   #1E293B;

    --color-blockquote-text: #475569;
    --color-blockquote-bg:   rgba(34, 197, 94, 0.06);

    --color-table-th-bg:  #F1F5F9;
    --color-selection-bg: #22C55E;
    --color-selection-text: #ffffff;
}

[data-theme="dark"] {
    --color-bg:           #0F172A;
    --color-surface:      #1E293B;
    --color-border:       #334155;
    --color-text:         #E2E8F0;
    --color-text-muted:   #94A3B8;
    --color-text-soft:    #64748B;
    --color-accent:       #5EDE6D;
    --color-accent-hover: #4ACA5A;

    --color-code-bg:      rgba(255, 255, 255, 0.08);
    --color-pre-bg:       #0D1117;
    --color-pre-text:     #E2E8F0;
    --color-pre-border:   #21262D;

    --color-blockquote-text: #CBD5E1;
    --color-blockquote-bg:   rgba(94, 222, 109, 0.06);

    --color-table-th-bg:  #1E293B;
    --color-selection-bg: #5EDE6D;
    --color-selection-text: #0F172A;
}

/* ========= Base ========= */

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    transition: background-color 0.2s ease, color 0.2s ease;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main { flex: 1 0 auto; }
.page-bg,
.topic-page-bg { flex: 1 0 auto; }

/* ========= Content Protection (Best-Effort) ========= */
.no-copy,
.no-copy * {
    -webkit-user-select: none;
    -ms-user-select: none;
    user-select: none;
}
.no-copy img { pointer-events: none; }

::selection {
    background: var(--color-selection-bg);
    color: var(--color-selection-text);
}

/* ========= Progress Bar ========= */
#progressBar {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    width: 0;
    background: var(--color-accent);
    z-index: 99999;
    transition: width 0.1s linear;
    pointer-events: none;
}

/* ========= Nav ========= */
.nav-link { transition: color 0.15s ease; }
.nav-link:hover { color: var(--color-accent); }

/* ========= Buttons ========= */
.btn-accent {
    border: 1px solid var(--color-accent);
    color: var(--color-accent);
    transition: all 0.15s ease;
}
.btn-accent:hover { background: var(--color-accent); color: #fff; }

/* ========= Card ========= */
.post-card { transition: transform 0.2s ease, box-shadow 0.2s ease; }
.post-card:hover { transform: translateY(-2px); }

/* ========= Form Inputs ========= */
input, textarea, select {
    color: var(--color-text);
    background-color: var(--color-surface);
    border-color: var(--color-border);
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
input::placeholder, textarea::placeholder { color: var(--color-text-soft); }

/* ========= Back To Top ========= */
#backToTop {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease, transform 0.2s ease,
    background-color 0.15s ease, color 0.15s ease;
}

/* ========= Sticky Header ========= */
#stickyHeader { z-index: 48; }

/* ========= Focus Overlay ========= */
#focusOverlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.55);
    z-index: 35;
    opacity: 0;
    transition: opacity 0.3s ease;
}
#mainContent { transition: z-index 0s; }

/* ========= TOC ========= */
#tocBar {
    display: none;
    position: sticky;
    top: 3.5rem;
    z-index: 40;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    transition: background 0.2s ease, border-color 0.2s ease;
}

#tocPanel::-webkit-scrollbar { width: 3px; }
#tocPanel::-webkit-scrollbar-track { background: transparent; }
#tocPanel::-webkit-scrollbar-thumb {
    background: var(--color-border);
    border-radius: 99px;
}

/* ========= End of Article ========= */
.article-end {
    margin-top: 3.5rem;
    padding-top: 2rem;
    border-top: 1px solid var(--color-border);
    text-align: center;
}
.article-end-marker {
    font-size: 0.72rem;
    letter-spacing: 0.2em;
    color: var(--color-text-muted);
    text-transform: uppercase;
}

/* ========= Code Blocks ========= */

pre {
    position: relative;
    border-radius: 12px;
    overflow: hidden;
    margin: 1.75rem 0;
    background: var(--color-pre-bg);
    color: var(--color-pre-text);
    padding: 0;
    border: 1px solid var(--color-pre-border);
    border-left: 3px solid var(--color-accent);
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.18);
}

pre code {
    display: block;
    font-size: 0.88rem;
    line-height: 1.7;
    background: transparent;
    color: inherit;
    padding: 0;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

/* Header bar */
.code-header {
    position: sticky;
    top: 0;
    height: 2.2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 0.6rem 0 0;
    background: rgba(15, 23, 42, 0.95);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    z-index: 2;
}

/* Language label */
.code-lang-label {
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    padding: 0.2rem 0.6rem;
    background: var(--color-accent);
    color: #fff;
    border-radius: 4px;
    margin-left: 0.75rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    line-height: 1;
}
[data-theme="dark"] .code-lang-label { color: #0F172A; }

/* Filename label */
.code-filename-label {
    font-size: 0.7rem;
    color: rgba(148, 163, 184, 0.7);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    padding-left: 0.75rem;
    flex: 1;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* Copy button */
.code-copy-btn {
    font-size: 0.7rem;
    padding: 0.2rem 0.55rem;
    border-radius: 5px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.05);
    color: #94A3B8;
    cursor: pointer;
    transition: all 0.15s ease;
    letter-spacing: 0.02em;
    font-family: inherit;
    flex-shrink: 0;
}
.code-copy-btn:hover {
    background: rgba(34, 197, 94, 0.15);
    border-color: rgba(34, 197, 94, 0.4);
    color: #5EDE6D;
}
.code-copy-btn:focus {
    outline: none;
    box-shadow: 0 0 0 2px rgba(34, 197, 94, 0.3);
}

/* Line numbers — flex approach */
.code-wrapper {
    display: flex;
    overflow-x: auto;
}

.code-line-numbers {
    padding: 1rem 0.75rem;
    text-align: right;
    font-size: 0.78rem;
    line-height: 1.7;
    color: rgba(148, 163, 184, 0.35);
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
    border-right: 1px solid rgba(255, 255, 255, 0.06);
    user-select: none;
    flex-shrink: 0;
    min-width: 2.5rem;
}

.code-content-wrap {
    padding: 1rem 1.25rem;
    flex: 1;
    white-space: pre;
    overflow-x: auto;
    font-size: 0.88rem;
    line-height: 1.7;
}

/* ========= Article Content ========= */

#articleContent {
    font-size: 1.05rem;
    line-height: 1.85;
    color: var(--color-text);
}

#articleContent p { margin: 1.3rem 0; color: var(--color-text); }

#articleContent h1 {
    font-size: 1.85rem; font-weight: 700;
    margin-top: 3rem; margin-bottom: 1rem;
    line-height: 1.2; color: var(--color-text);
}
#articleContent h2 {
    font-size: 1.5rem; font-weight: 700;
    margin-top: 2.75rem; margin-bottom: 0.85rem;
    line-height: 1.25; color: var(--color-text);
    padding-bottom: 0.4rem;
    border-bottom: 1px solid var(--color-border);
}
#articleContent h3 {
    font-size: 1.2rem; font-weight: 600;
    margin-top: 2.25rem; margin-bottom: 0.7rem;
    line-height: 1.3; color: var(--color-text);
}
#articleContent h4, #articleContent h5, #articleContent h6 {
    font-size: 1rem; font-weight: 600;
    margin-top: 1.75rem; margin-bottom: 0.5rem;
    color: var(--color-text);
}

/* Lists */
#articleContent ul {
    list-style: none;
    margin: 1.25rem 0 1.25rem 0.5rem;
}
#articleContent ol {
    list-style-type: decimal;
    margin: 1.25rem 0 1.25rem 1.5rem;
    color: var(--color-text);
}
#articleContent li { margin: 0.45rem 0; color: var(--color-text); }

/* Level 1 bullet */
#articleContent ul > li {
    position: relative;
    padding-left: 1.3rem;
}
#articleContent ul > li::before {
    content: "–";
    position: absolute;
    top: -0.1rem;
    left: 0;
    color: var(--color-accent);
    font-weight: 700;
}

/* Level 2 bullet */
#articleContent ul > li > ul {
    margin: 0.3rem 0 0.3rem 0.5rem;
}
#articleContent ul > li > ul > li {
    position: relative;
    padding-left: 1.3rem;
}
#articleContent ul > li > ul > li::before {
    content: "·";
    position: absolute;
    left: 0;
    top: -0.8rem;
    font-size: 3rem;
    line-height: 1;
    color: var(--color-text-muted);
    font-weight: 400;
}

/* Level 3 bullet */
#articleContent ul > li > ul > li > ul > li {
    position: relative;
    padding-left: 1.3rem;
}
#articleContent ul > li > ul > li > ul > li::before {
    content: "○";
    position: absolute;
    left: 0;
    top: 0.7rem;
    font-size: 0.55rem;
    color: var(--color-text-soft);
}

#articleContent blockquote {
    border-left: 3px solid var(--color-accent);
    padding: 0.65rem 1.1rem;
    margin: 1.75rem 0;
    background: var(--color-blockquote-bg);
    border-radius: 0 8px 8px 0;
    color: var(--color-blockquote-text);
    font-style: italic;
}

#articleContent :not(pre) > code {
    padding: 2px 6px;
    border-radius: 5px;
    background: var(--color-code-bg);
    color: var(--color-text);
    font-size: 0.88em;
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

#articleContent hr {
    border: none;
    border-top: 1px solid var(--color-border);
    margin: 2.5rem 0;
}

#articleContent strong { font-weight: 700; color: var(--color-text); }
#articleContent em { font-style: italic; }

#articleContent img {
    max-width: 100%; height: auto;
    border-radius: 10px; margin: 1.75rem 0;
    border: 1px solid var(--color-border);
}

#articleContent table {
    width: 100%; border-collapse: collapse;
    margin: 1.75rem 0; font-size: 0.95rem;
    color: var(--color-text);
}
#articleContent th {
    background: var(--color-table-th-bg);
    font-weight: 600; text-align: left;
    padding: 0.65rem 1rem;
    border-bottom: 2px solid var(--color-border);
    color: var(--color-text);
}
#articleContent td {
    padding: 0.65rem 1rem;
    border-bottom: 1px solid var(--color-border);
    color: var(--color-text);
}

#articleContent figcaption {
    text-align: center; font-size: 0.875rem;
    color: var(--color-text-soft);
    margin-top: -1rem; margin-bottom: 1.25rem;
}

#articleContent a {
    color: var(--color-accent); font-weight: 500;
    text-decoration: none; transition: color 0.15s ease;
}
#articleContent a:hover {
    text-decoration: underline;
    color: var(--color-accent-hover);
}
#articleContent a:active { opacity: 0.8; }

/* ========= Custom Dividers ========= */
hr.divider-bold {
    border: none;
    border-top: 2px solid var(--color-border);
    margin: 2.5rem 0;
}
hr.divider-dashed {
    border: none;
    border-top: 1px dashed var(--color-border);
    margin: 2.5rem 0;
}
hr.divider-bold-dashed {
    border: none;
    border-top: 2px dashed var(--color-border);
    margin: 2.5rem 0;
}

/* ========= Callouts ========= */
.callout {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0.9rem 1rem;
    margin: 1.75rem 0;
    border-radius: 8px;
    font-size: 0.95rem;
    line-height: 1.6;
    border: 1px solid transparent;
    color: var(--color-text);
}
.callout-icon { flex-shrink: 0; font-size: 1rem; margin-top: 0.05rem; }
.callout-body { flex: 1; }
.callout-body p { margin: 0 !important; color: inherit !important; }

.callout.tip     { background: rgba(34,197,94,0.07);   border-color: rgba(34,197,94,0.25); }
.callout.warning { background: rgba(234,179,8,0.07);   border-color: rgba(234,179,8,0.3); }
.callout.concept { background: rgba(99,102,241,0.07);  border-color: rgba(99,102,241,0.25); }
.callout.note    { background: rgba(148,163,184,0.07); border-color: rgba(148,163,184,0.25); }
.callout.danger  { background: rgba(239,68,68,0.07);   border-color: rgba(239,68,68,0.25); }

[data-theme="dark"] .callout.tip     { background: rgba(94,222,109,0.07);   border-color: rgba(94,222,109,0.2); }
[data-theme="dark"] .callout.warning { background: rgba(234,179,8,0.08);    border-color: rgba(234,179,8,0.25); }
[data-theme="dark"] .callout.concept { background: rgba(129,140,248,0.08);  border-color: rgba(129,140,248,0.2); }
[data-theme="dark"] .callout.note    { background: rgba(148,163,184,0.06);  border-color: rgba(148,163,184,0.2); }
[data-theme="dark"] .callout.danger  { background: rgba(239,68,68,0.08);    border-color: rgba(239,68,68,0.25); }

/* ========= Toggle ========= */
.toggle {
    margin: 1.5rem 0;
    border: 1px solid var(--color-border);
    border-radius: 8px;
    overflow: hidden;
}
.toggle-summary {
    padding: 0.8rem 1rem;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    color: var(--color-text);
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    user-select: none;
    transition: background 0.15s ease;
}
.toggle-summary::-webkit-details-marker { display: none; }
.toggle-summary::after {
    content: "＋";
    font-size: 0.85rem;
    color: var(--color-text-muted);
    flex-shrink: 0;
    margin-left: 0.5rem;
}
.toggle[open] .toggle-summary::after { content: "－"; }
.toggle-summary:hover { background: var(--color-blockquote-bg); }
.toggle-body {
    padding: 0.85rem 1rem;
    border-top: 1px solid var(--color-border);
    font-size: 0.95rem;
    line-height: 1.7;
    color: var(--color-text-muted);
}