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

:root {
    --gh-bg: #0d1117;
    --gh-surface: #161b22;
    --gh-surface2: #21262d;
    --gh-border: #30363d;
    --gh-border-muted: #21262d;
    --gh-text: #e6edf3;
    --gh-text-muted: #8b949e;
    --gh-accent: #58a6ff;
    --gh-green: #3fb950;
    --gh-green-dim: #238636;
    --gh-orange: #f0883e;
    --gh-red: #f85149;
    --gh-yellow: #e3b341;
    --gh-header-bg: #161b22;
    --gh-header-border: #21262d;
    --radius-sm: 6px;
    --radius-md: 8px;
    --mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;
}

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
    background: var(--gh-bg);
    color: var(--gh-text);
    min-height: 100vh;
    font-size: 14px;
    line-height: 1.5;
}

.gh-header {
    background: var(--gh-header-bg);
    border-bottom: 1px solid var(--gh-header-border);
    padding: 0 16px;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
}

.gh-header-inner {
    max-width: 1280px;
    margin: 0 auto;
    height: 56px;
    display: flex;
    align-items: center;
    gap: 16px;
}

.gh-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--gh-text);
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
}

.gh-logo svg {
    width: 32px;
    height: 32px;
    fill: currentColor;
    flex-shrink: 0;
}

.gh-breadcrumb {
    display: flex;
    align-items: center;
    gap: 6px;
    color: var(--gh-text-muted);
    font-size: 14px;
}

.gh-breadcrumb a,
.gh-footer a {
    color: var(--gh-accent);
    text-decoration: none;
}

.gh-breadcrumb a:hover,
.gh-footer a:hover {
    text-decoration: underline;
}

.gh-breadcrumb .sep { color: var(--gh-border); }

.header-spacer { flex: 1; }

.gh-header-actions {
    display: flex;
    gap: 8px;
    align-items: center;
}

.lang-switcher { position: relative; }

.lang-btn {
    background: var(--gh-surface2);
    color: var(--gh-text);
    border: 1px solid var(--gh-border);
    padding: 5px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 5px;
    transition: background 0.15s, border-color 0.15s;
}

.lang-btn:hover { background: var(--gh-border); border-color: #8b949e; }

.lang-btn .caret { font-size: 10px; opacity: 0.7; }

.lang-menu {
    display: none;
    position: absolute;
    right: 0;
    top: calc(100% + 6px);
    background: var(--gh-surface);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-md);
    min-width: 160px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.4);
    overflow: hidden;
    z-index: 200;
}

.lang-menu.open { display: block; animation: menuFade 0.12s ease; }

.lang-menu button {
    width: 100%;
    background: none;
    border: none;
    color: var(--gh-text);
    padding: 8px 14px;
    text-align: left;
    cursor: pointer;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: background 0.1s;
}

.lang-menu button:hover { background: var(--gh-surface2); }

.lang-menu button .check { width: 14px; color: var(--gh-green); }

.hidden { visibility: hidden; }

.main-layout {
    max-width: 1280px;
    margin: 0 auto;
    padding: 24px 16px 48px;
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: 16px;
}

.content-stack,
.sidebar {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.panel {
    background: var(--gh-surface);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-md);
    overflow: hidden;
    animation: fadeIn 0.25s ease backwards;
}

.panel:nth-child(2) { animation-delay: 0.05s; }
.panel:nth-child(3) { animation-delay: 0.1s; }

.panel-header {
    padding: 10px 16px;
    border-bottom: 1px solid var(--gh-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: var(--gh-surface2);
}

.panel-title {
    font-weight: 600;
    font-size: 13px;
    display: flex;
    align-items: center;
    gap: 7px;
}

.panel-title svg {
    width: 16px;
    height: 16px;
    fill: var(--gh-text-muted);
}

.panel-body { padding: 16px; }

.form-group { margin-bottom: 14px; }
.form-group-last { margin-bottom: 0; }

.form-label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gh-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 6px;
}

textarea,
select,
input {
    width: 100%;
    background: var(--gh-bg);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-sm);
    color: var(--gh-text);
    font-size: 14px;
    font-family: var(--mono);
    padding: 8px 12px;
    outline: none;
    transition: border-color 0.15s, box-shadow 0.15s;
    appearance: none;
}

textarea:focus,
select:focus,
input:focus {
    border-color: var(--gh-accent);
    box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.12);
}

textarea { resize: vertical; min-height: 80px; line-height: 1.6; }

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    border: none;
    border-radius: var(--radius-sm);
    padding: 7px 16px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.15s, transform 0.1s;
    white-space: nowrap;
}

.btn:active { transform: scale(0.97); }
.btn svg { fill: currentColor; }

.btn-primary {
    background: var(--gh-green-dim);
    color: #fff;
    border: 1px solid rgba(240, 246, 252, 0.1);
    width: 100%;
    padding: 9px;
    margin-top: 4px;
    font-size: 14px;
}

.btn-primary:hover { background: var(--gh-green); }

.btn-secondary {
    background: var(--gh-surface2);
    color: var(--gh-text);
    border: 1px solid var(--gh-border);
    font-size: 12px;
    padding: 5px 12px;
}

.btn-secondary:hover { background: var(--gh-border); }

.btn-secondary.copied {
    background: var(--gh-green-dim);
    color: #fff;
    border-color: transparent;
}

.icon-xs { width: 12px; height: 12px; }
.icon-sm { width: 14px; height: 14px; }
.icon-md { width: 14px; height: 14px; }

.align-btns {
    display: flex;
    gap: 6px;
    padding: 12px 16px;
}

.align-btn {
    flex: 1;
    background: var(--gh-surface2);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-sm);
    color: var(--gh-text-muted);
    padding: 7px 8px;
    cursor: pointer;
    font-size: 12px;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 5px;
    transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.align-btn:hover { background: var(--gh-border); color: var(--gh-text); }

.align-btn.active {
    background: rgba(88, 166, 255, 0.12);
    border-color: var(--gh-accent);
    color: var(--gh-accent);
}

.align-btn svg {
    width: 13px;
    height: 13px;
    fill: currentColor;
}

.tabs-nav {
    display: flex;
    border-bottom: 1px solid var(--gh-border);
    padding: 0 16px;
    background: var(--gh-surface2);
    gap: 2px;
}

.tab-item {
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    color: var(--gh-text-muted);
    padding: 10px 12px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: -1px;
    transition: color 0.15s;
}

.tab-item:hover { color: var(--gh-text); }
.tab-item.active { color: var(--gh-text); border-bottom-color: var(--gh-orange); }

.tab-pane { display: none; padding: 16px; }
.tab-pane.active { display: block; }

.output-wrap { position: relative; }

.output-toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 8px;
}

.output-meta {
    display: flex;
    align-items: center;
    gap: 10px;
}

.output-badge {
    background: rgba(56, 139, 253, 0.08);
    border: 1px solid rgba(56, 139, 253, 0.15);
    color: var(--gh-accent);
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 11px;
    font-family: var(--mono);
    font-weight: 600;
}

.line-count {
    color: var(--gh-text-muted);
    font-size: 12px;
    font-family: var(--mono);
}

.code-block {
    background: var(--gh-bg);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-sm);
    overflow: auto;
    position: relative;
}

.code-block textarea {
    border: none;
    border-radius: 0;
    background: transparent;
    width: 100%;
    resize: none;
    font-size: 12px;
    line-height: 1.6;
    padding: 16px;
    min-height: 220px;
    font-family: var(--mono);
}

.code-block textarea:focus { box-shadow: none; }

.code-inner { display: flex; }

.line-nums {
    padding: 16px 8px 16px 12px;
    background: rgba(255, 255, 255, 0.02);
    border-right: 1px solid var(--gh-border);
    user-select: none;
    flex-shrink: 0;
    font-family: var(--mono);
    font-size: 12px;
    line-height: 1.6;
    color: var(--gh-text-muted);
    text-align: right;
    min-width: 42px;
    white-space: pre;
}

.preview-block {
    background: var(--gh-bg);
    border: 1px solid var(--gh-border);
    border-radius: var(--radius-sm);
    padding: 24px 20px;
    min-height: 220px;
    overflow-x: auto;
}

.preview-block pre {
    font-family: var(--mono);
    font-size: 12px;
    line-height: 1.2;
    color: var(--gh-text);
}

.preview-content pre {
    font-family: var(--mono);
    font-size: 11px;
    line-height: 1.2;
}

.status-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 6px 12px;
    background: var(--gh-surface2);
    border-top: 1px solid var(--gh-border);
    font-size: 12px;
    color: var(--gh-text-muted);
    font-family: var(--mono);
    min-height: 32px;
}

.status-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--gh-text-muted);
    flex-shrink: 0;
    transition: background 0.3s;
}

.status-dot.ok { background: var(--gh-green); box-shadow: 0 0 6px var(--gh-green); }
.status-dot.err { background: var(--gh-red); box-shadow: 0 0 6px var(--gh-red); }
.status-dot.loading { background: var(--gh-yellow); animation: pulse 1s infinite; }

#statusMsg { transition: color 0.2s; }
#statusMsg.err { color: var(--gh-red); }
#statusMsg.ok { color: var(--gh-green); }

.status-font {
    margin-left: auto;
    color: var(--gh-text-muted);
    opacity: 0.5;
}

.info-block { padding: 14px 16px; }

.info-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 6px 0;
    border-bottom: 1px solid var(--gh-border-muted);
    font-size: 13px;
}

.info-row:last-child { border: none; }
.info-row .key { color: var(--gh-text-muted); }
.info-row .val { font-family: var(--mono); font-weight: 600; }

.font-preview-list { padding: 0 0 4px; max-height: 340px; overflow-y: auto; }
.font-preview-list::-webkit-scrollbar { width: 6px; }
.font-preview-list::-webkit-scrollbar-track { background: transparent; }
.font-preview-list::-webkit-scrollbar-thumb { background: var(--gh-border); border-radius: 3px; }

.font-item {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 9px 16px;
    cursor: pointer;
    transition: background 0.12s;
    border: none;
    border-bottom: 1px solid var(--gh-border-muted);
    background: transparent;
    color: inherit;
    text-align: left;
    font: inherit;
}

.font-item:last-child { border: none; }
.font-item:hover { background: var(--gh-surface2); }
.font-item.active { background: rgba(56, 139, 253, 0.07); }

.font-item .font-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--gh-border);
    flex-shrink: 0;
    transition: background 0.15s;
}

.font-item.active .font-dot { background: var(--gh-accent); }
.font-item .font-name { font-size: 13px; font-weight: 500; }
.font-item .font-hint { font-size: 11px; color: var(--gh-text-muted); margin-left: auto; }

.usage-copy {
    color: var(--gh-text-muted);
    font-size: 13px;
    line-height: 1.6;
}

.inline-code {
    background: var(--gh-surface2);
    padding: 1px 5px;
    border-radius: 3px;
    font-size: 12px;
}

.gh-footer {
    border-top: 1px solid var(--gh-border);
    padding: 24px 16px;
    text-align: center;
    color: var(--gh-text-muted);
    font-size: 12px;
}

@media (max-width: 900px) {
    .main-layout { grid-template-columns: 1fr; }
    .sidebar { order: -1; }
}

@keyframes menuFade {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: none; }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: none; }
}