@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700;800;900&family=Poppins:ital,wght@0,300;0,400;0,500;0,600;0,700;1,400&display=swap');

/* ── TOKENS ── */
:root {
  --gold:        #F5B800;
  --gold-light:  #FFD640;
  --gold-dim:    rgba(245,184,0,0.10);
  --gold-border: rgba(245,184,0,0.28);
  --black:       #0B0B0B;
  --dark:        #111111;
  --card:        #161616;
  --card2:       #1D1D1D;
  --border:      rgba(255,255,255,0.07);
  --border2:     rgba(255,255,255,0.13);
  --text:        #E4E2DC;
  --muted:       #88847F;
  --muted2:      #525050;
  --white:       #FFFFFF;
  --code-bg:     #0D0D0D;

  --topbar-h:   56px;
  --sidebar-w:  270px;

  --font-head: 'Montserrat', sans-serif;
  --font-body: 'Poppins', sans-serif;
  --font-code: 'Courier New', Courier, monospace;

  /* per-language accent */
  --py-color:  #4B9EFF;
  --dj-color:  #44D990;
  --fa-color:  #B97BFF;
  --fl-color:  #FF8C42;
}

:root[data-theme='light'] {
  --gold-dim:    rgba(245,184,0,0.16);
  --gold-border: rgba(245,184,0,0.42);
  --black:       #F3F4F6;
  --dark:        #FFFFFF;
  --card:        #FFFFFF;
  --card2:       #F3F4F6;
  --border:      rgba(17,24,39,0.12);
  --border2:     rgba(17,24,39,0.2);
  --text:        #111827;
  --muted:       #4B5563;
  --muted2:      #6B7280;
  --white:       #111827;
  --code-bg:     #F8FAFC;
}

/* ── RESET ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
  background: var(--black); color: var(--text);
  font-family: var(--font-body); font-size: 15px; line-height: 1.75;
  overflow-x: hidden;
}
:root, body, .topbar, .sidebar, .code-block, .tryit-panel, .quiz-box, .main-footer {
  transition: background-color 0.22s ease, color 0.22s ease, border-color 0.22s ease;
}
a { text-decoration: none; color: inherit; }
ul { list-style: none; }
h1,h2,h3,h4 { font-family: var(--font-head); letter-spacing: -0.02em; color: var(--white); }

/* ── TOP NAV ── */
.topbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 300;
  height: var(--topbar-h);
  background: var(--dark);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center;
  padding: 0 20px; gap: 10px;
}
.topbar-logo {
  display: flex; align-items: center;
  margin-right: 12px; white-space: nowrap;
  text-decoration: none;
  min-width: 0;
}
.topbar-logo img {
  height: 34px;
  width: auto;
  max-width: clamp(120px, 16vw, 180px);
  object-fit: contain;
  display: block;
}

.topbar-nav {
  display: flex; align-items: center; gap: 2px; flex: 1;
}
.topbar-nav a {
  display: flex; align-items: center; gap: 6px;
  padding: 6px 14px; border-radius: 6px;
  font-family: var(--font-head); font-size: 11px; font-weight: 700;
  color: var(--muted); transition: all 0.18s;
  text-transform: uppercase; letter-spacing: 0.06em;
}
.topbar-nav a:hover { color: var(--white); background: rgba(255,255,255,0.05); }
.topbar-nav a.active { color: var(--gold); background: var(--gold-dim); }
.topbar-nav a .dot {
  width: 7px; height: 7px; border-radius: 50%; flex-shrink: 0;
}
.topbar-search {
  display: flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--border2);
  border-radius: 7px; padding: 7px 14px;
  transition: border-color 0.2s;
  width: clamp(170px, 21vw, 230px);
}
.topbar-search:focus-within { border-color: var(--gold-border); }
.topbar-search input {
  background: none; border: none; outline: none;
  font-family: var(--font-body); font-size: 13px; color: var(--text);
  width: 100%;
}
.topbar-search input::placeholder { color: var(--muted2); }
.topbar-search .icon { color: var(--muted); font-size: 13px; }

.theme-toggle {
  margin-left: auto;
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border2);
  border-radius: 8px;
  padding: 7px 12px;
  font-family: var(--font-head);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 0.2s;
}
.theme-toggle:hover {
  border-color: var(--gold-border);
  color: var(--gold);
}

:root[data-theme='light'] .topbar-search {
  background: rgba(15,23,42,0.04);
}
:root[data-theme='light'] .topbar-nav a:hover {
  background: rgba(15,23,42,0.06);
}
:root[data-theme='light'] .btn-copy {
  background: rgba(15,23,42,0.04);
}
:root[data-theme='light'] .styled-table tr:hover td {
  background: rgba(15,23,42,0.04);
}

/* ── LAYOUT ── */
.layout {
  display: flex;
  padding-top: var(--topbar-h);
  min-height: 100vh;
}

/* ── SIDEBAR ── */
.sidebar {
  position: fixed;
  top: var(--topbar-h); left: 0; bottom: 0;
  width: var(--sidebar-w);
  background: var(--dark);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  z-index: 200;
}
.sidebar::-webkit-scrollbar { width: 3px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border2); border-radius: 2px; }

.sidebar-header {
  padding: 18px 20px 10px;
  font-family: var(--font-head); font-size: 10px; font-weight: 800;
  color: var(--muted2); text-transform: uppercase; letter-spacing: 0.14em;
  border-bottom: 1px solid var(--border);
  margin-bottom: 6px;
}
.sidebar-section {
  padding: 12px 20px 4px;
  font-family: var(--font-head); font-size: 9px; font-weight: 800;
  color: var(--muted2); text-transform: uppercase; letter-spacing: 0.12em;
}
.sidebar a {
  display: flex; align-items: center; justify-content: space-between;
  padding: 8px 20px;
  font-family: var(--font-body); font-size: 13px; font-weight: 400;
  color: var(--muted); transition: all 0.15s;
  border-left: 2px solid transparent;
}
.sidebar a:hover { color: var(--text); background: rgba(255,255,255,0.03); }
.sidebar a.active {
  color: var(--gold); font-weight: 600;
  background: var(--gold-dim);
  border-left-color: var(--gold);
}
.sidebar a .badge-new {
  font-family: var(--font-head); font-size: 8px; font-weight: 800;
  background: var(--gold); color: var(--black);
  padding: 1px 6px; border-radius: 100px; text-transform: uppercase;
}

/* ── MAIN CONTENT ── */
.main {
  margin-left: var(--sidebar-w);
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: calc(100vh - var(--topbar-h));
}
.content {
  flex: 1;
  max-width: 860px;
  padding: 40px 52px 80px;
}

/* ── TOPIC PAGE STRUCTURE ── */
.topic-header {
  margin-bottom: 28px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--border);
}
.topic-breadcrumb {
  font-family: var(--font-head); font-size: 10px; font-weight: 600;
  color: var(--muted); text-transform: uppercase; letter-spacing: 0.1em;
  margin-bottom: 10px; display: flex; align-items: center; gap: 6px;
}
.topic-breadcrumb a { color: var(--gold); }
.topic-breadcrumb span { color: var(--muted2); }
.topic-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 800; color: var(--white); margin-bottom: 10px;
}
.topic-subtitle {
  font-size: 15px; color: var(--muted); line-height: 1.8;
  max-width: 620px;
}

/* ── CONTENT ELEMENTS ── */
.topic-content h2 {
  font-size: 1.15rem; font-weight: 700; color: var(--white);
  margin: 32px 0 10px;
}
.topic-content h3 {
  font-size: 1rem; font-weight: 600; color: var(--text);
  margin: 22px 0 8px;
}
.topic-content p {
  color: var(--muted); margin-bottom: 14px; line-height: 1.8;
}
.topic-content ul, .topic-content ol {
  padding-left: 20px; margin-bottom: 14px;
  display: flex; flex-direction: column; gap: 5px;
}
.topic-content li { color: var(--muted); font-size: 14px; }
.topic-content li strong { color: var(--text); }
.topic-content strong { color: var(--text); }
.topic-content code {
  background: rgba(245,184,0,0.1); border: 1px solid var(--gold-border);
  border-radius: 4px; padding: 1px 7px;
  font-family: var(--font-code); font-size: 12.5px; color: var(--gold);
}

/* ── NOTE / TIP BOXES ── */
.note, .tip, .warning {
  border-radius: 8px; padding: 14px 18px;
  margin: 18px 0; font-size: 13.5px; line-height: 1.7;
  display: flex; gap: 12px; align-items: flex-start;
}
.note    { background: rgba(75,158,255,0.07);  border-left: 3px solid #4B9EFF; color: #91c0ff; }
.tip     { background: rgba(68,217,144,0.07);  border-left: 3px solid #44D990; color: #7dedb4; }
.warning { background: rgba(255,140,66,0.07);  border-left: 3px solid #FF8C42; color: #ffc69c; }
.note strong, .tip strong, .warning strong { color: inherit; }
.note-icon { font-size: 16px; flex-shrink: 0; margin-top: 1px; }

/* ── CODE BLOCK ── */
.code-block {
  background: var(--code-bg);
  border: 1px solid var(--border2);
  border-radius: 10px;
  overflow: hidden;
  margin: 18px 0;
}
.code-block-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 16px;
  background: rgba(255,255,255,0.03);
  border-bottom: 1px solid var(--border);
}
.code-block-lang {
  font-family: var(--font-head); font-size: 10px; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.1em; color: var(--muted);
}
.code-block-actions { display: flex; gap: 8px; }
.btn-copy, .btn-run {
  font-family: var(--font-head); font-size: 10px; font-weight: 700;
  padding: 4px 12px; border-radius: 5px; border: none;
  cursor: pointer; transition: all 0.18s; letter-spacing: 0.04em;
  text-transform: uppercase;
}
.btn-copy {
  background: rgba(255,255,255,0.06); color: var(--muted);
  border: 1px solid var(--border2);
}
.btn-copy:hover { background: rgba(255,255,255,0.1); color: var(--text); }
.btn-run {
  background: var(--gold); color: var(--black);
}
.btn-run:hover { background: var(--gold-light); }
.btn-run:disabled,
.btn-run-code:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}

.code-block pre {
  padding: 18px 20px; overflow-x: auto;
  font-family: var(--font-code); font-size: 13px;
  line-height: 1.75; color: #C8C2B8; background: none; border: none;
}
.code-block pre .kw  { color: #F5B800; }
.code-block pre .fn  { color: #7BC8A4; }
.code-block pre .str { color: #C8A47B; }
.code-block pre .cm  { color: #4A4845; font-style: italic; }
.code-block pre .num { color: #B97BFF; }
.code-block pre .cls { color: #4B9EFF; }

/* ── TRY IT PANEL ── */
.tryit-panel {
  border: 1px solid var(--gold-border);
  border-radius: 12px; overflow: hidden;
  margin: 24px 0;
  background: var(--code-bg);
}
.tryit-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 18px;
  background: rgba(245,184,0,0.07);
  border-bottom: 1px solid var(--gold-border);
}
.tryit-title {
  font-family: var(--font-head); font-size: 11px; font-weight: 800;
  color: var(--gold); text-transform: uppercase; letter-spacing: 0.1em;
  display: flex; align-items: center; gap: 8px;
}
.tryit-title::before { content: '▶'; font-size: 9px; }
.tryit-toolbar { display: flex; gap: 8px; align-items: center; }
.tryit-lang-tag {
  font-family: var(--font-head); font-size: 9px; font-weight: 700;
  padding: 3px 9px; border-radius: 100px; text-transform: uppercase;
  background: var(--gold-dim); color: var(--gold); border: 1px solid var(--gold-border);
}
.btn-run-code {
  background: var(--gold); color: var(--black);
  border: none; padding: 7px 20px; border-radius: 6px;
  font-family: var(--font-head); font-size: 11px; font-weight: 800;
  cursor: pointer; transition: all 0.18s; letter-spacing: 0.04em;
  display: flex; align-items: center; gap: 6px;
}
.btn-run-code:hover { background: var(--gold-light); transform: translateY(-1px); }
.btn-clear-output {
  background: transparent; color: var(--muted);
  border: 1px solid var(--border2); padding: 7px 14px; border-radius: 6px;
  font-family: var(--font-head); font-size: 10px; font-weight: 700;
  cursor: pointer; transition: all 0.18s;
}
.btn-clear-output:hover { color: var(--text); border-color: var(--border2); }

.tryit-editor-wrap {
  display: grid; grid-template-columns: 1fr 1fr;
  min-height: 240px;
}
.tryit-editor-pane {
  border-right: 1px solid var(--border);
  display: flex; flex-direction: column;
}
.tryit-output-pane { display: flex; flex-direction: column; }
.tryit-pane-label {
  padding: 6px 14px;
  font-family: var(--font-head); font-size: 9px; font-weight: 800;
  color: var(--muted2); text-transform: uppercase; letter-spacing: 0.1em;
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,0.02);
}

.tryit-textarea {
  flex: 1; background: transparent; border: none; outline: none;
  padding: 16px 18px; resize: none;
  font-family: var(--font-code); font-size: 13px;
  color: #C8C2B8; line-height: 1.75;
  min-height: 200px;
}
.tryit-textarea::selection { background: rgba(245,184,0,0.2); }

.tryit-output {
  flex: 1; padding: 16px 18px; overflow-y: auto;
  font-family: var(--font-code); font-size: 13px;
  color: #C8C2B8; line-height: 1.75; min-height: 200px;
  white-space: pre-wrap; word-break: break-word;
}
.tryit-output.has-error { color: #FF7070; }
.tryit-output .out-success { color: #7BC8A4; }
.tryit-output .out-label {
  font-family: var(--font-head); font-size: 9px; font-weight: 700;
  color: var(--muted2); text-transform: uppercase; letter-spacing: 0.1em;
  margin-bottom: 8px; display: block;
}
.tryit-status {
  padding: 6px 14px; border-top: 1px solid var(--border);
  font-family: var(--font-head); font-size: 10px; font-weight: 600;
  color: var(--muted2); display: flex; align-items: center; gap: 6px;
}
.tryit-status.running { color: var(--gold); }
.tryit-status.done    { color: #44D990; }
.tryit-status.error   { color: #FF7070; }
.status-dot { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }

:root[data-theme='light'] .code-block pre,
:root[data-theme='light'] .tryit-textarea,
:root[data-theme='light'] .tryit-output {
  color: #1F2937;
}
:root[data-theme='light'] .code-block pre .kw { color: #B45309; }
:root[data-theme='light'] .code-block pre .fn { color: #0F766E; }
:root[data-theme='light'] .code-block pre .str { color: #7C2D12; }
:root[data-theme='light'] .code-block pre .cm { color: #64748B; }
:root[data-theme='light'] .code-block pre .num { color: #6D28D9; }
:root[data-theme='light'] .code-block pre .cls { color: #1D4ED8; }

/* ── PREV / NEXT NAV ── */
.page-nav {
  display: flex; gap: 14px; margin: 40px 0 20px;
  padding-top: 28px; border-top: 1px solid var(--border);
}
.page-nav-btn {
  flex: 1; display: flex; align-items: center; gap: 14px;
  background: var(--card); border: 1px solid var(--border);
  border-radius: 10px; padding: 16px 20px;
  font-family: var(--font-body); cursor: pointer;
  transition: all 0.2s; text-decoration: none;
}
.page-nav-btn:hover { border-color: var(--gold-border); background: var(--card2); }
.page-nav-btn.next { flex-direction: row-reverse; text-align: right; }
.page-nav-arrow { font-size: 18px; color: var(--gold); flex-shrink: 0; }
.page-nav-label {
  font-family: var(--font-head); font-size: 9px; font-weight: 700;
  color: var(--muted); text-transform: uppercase; letter-spacing: 0.1em;
  margin-bottom: 3px;
}
.page-nav-title {
  font-family: var(--font-head); font-size: 13px; font-weight: 700;
  color: var(--text);
}

/* ── BUTTONS ── */
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--gold); color: var(--black);
  padding: 11px 26px; border-radius: 7px;
  font-family: var(--font-head); font-weight: 700; font-size: 12px;
  letter-spacing: 0.04em; text-transform: uppercase;
  transition: all 0.18s; border: none; cursor: pointer;
}
.btn-primary:hover { background: var(--gold-light); transform: translateY(-1px); box-shadow: 0 8px 28px rgba(245,184,0,0.22); }
.btn-outline {
  display: inline-flex; align-items: center; gap: 8px;
  background: transparent; color: var(--text);
  padding: 11px 26px; border-radius: 7px;
  border: 1px solid var(--border2);
  font-family: var(--font-head); font-weight: 600; font-size: 12px;
  letter-spacing: 0.04em; text-transform: uppercase;
  transition: all 0.18s; cursor: pointer;
}
.btn-outline:hover { border-color: rgba(255,255,255,0.28); color: var(--white); }

/* ── QUIZ BOX ── */
.quiz-box {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 12px; padding: 24px; margin: 24px 0;
}
.quiz-box-title {
  font-family: var(--font-head); font-size: 12px; font-weight: 800;
  color: var(--gold); text-transform: uppercase; letter-spacing: 0.1em;
  margin-bottom: 14px; display: flex; align-items: center; gap: 8px;
}
.quiz-box-title::before { content: '🧠'; }
.quiz-q { font-size: 14px; color: var(--text); margin-bottom: 12px; font-weight: 500; }
.quiz-options { display: flex; flex-direction: column; gap: 8px; }
.quiz-opt {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 14px; border-radius: 7px;
  border: 1px solid var(--border); cursor: pointer;
  font-size: 13px; color: var(--muted); transition: all 0.15s;
  background: transparent;
  font-family: var(--font-body);
  text-align: left; width: 100%;
}
.quiz-opt:hover { border-color: var(--border2); color: var(--text); }
.quiz-opt.correct { border-color: #44D990; background: rgba(68,217,144,0.07); color: #44D990; }
.quiz-opt.wrong   { border-color: #FF7070; background: rgba(255,112,112,0.07); color: #FF7070; }
.quiz-result { margin-top: 12px; font-size: 13px; font-weight: 600; min-height: 20px; }
.quiz-result.pass { color: #44D990; }
.quiz-result.fail { color: #FF7070; }

/* ── TABLE ── */
.styled-table {
  width: 100%; border-collapse: collapse; margin: 16px 0;
  font-size: 13px;
}
.styled-table th {
  background: var(--card2); color: var(--gold);
  font-family: var(--font-head); font-size: 10px; font-weight: 800;
  text-transform: uppercase; letter-spacing: 0.1em;
  padding: 10px 14px; border: 1px solid var(--border);
  text-align: left;
}
.styled-table td {
  padding: 9px 14px; border: 1px solid var(--border);
  color: var(--muted);
}
.styled-table tr:hover td { background: rgba(255,255,255,0.02); }
.styled-table td code { font-size: 12px; }

/* ── FOOTER ── */
.main-footer {
  margin-left: var(--sidebar-w);
  border-top: 1px solid var(--border);
  padding: 22px 52px;
  display: flex; align-items: center; justify-content: space-between;
  flex-wrap: wrap; gap: 12px;
}
.main-footer p { font-size: 12px; color: var(--muted2); font-family: var(--font-body); }
.main-footer a { color: var(--gold); }

/* ── SCROLL REVEAL ── */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity 0.5s, transform 0.5s; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ── RESPONSIVE ── */
.menu-toggle {
  display: none; align-items: center; justify-content: center;
  width: 36px; height: 36px; border-radius: 7px;
  background: rgba(255,255,255,0.05); border: 1px solid var(--border2);
  cursor: pointer; color: var(--text); font-size: 16px;
  margin-right: 8px; flex-shrink: 0;
}
body.sidebar-open { overflow: hidden; }

@media (max-width: 1150px) {
  :root { --sidebar-w: 240px; }
  .content { padding: 34px 30px 70px; }
  .main-footer { padding: 20px 30px; }
  .topbar-search { min-width: 140px; }
}

@media (max-width: 920px) {
  .topbar { padding: 0 12px; gap: 8px; }
  .topbar-logo img { height: 30px; }
  .topbar-nav { display: none; }
  .menu-toggle { display: flex; }
}

@media (max-width: 800px) {
  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.28s;
    width: min(84vw, 320px);
    box-shadow: 0 18px 45px rgba(0,0,0,0.35);
  }
  .sidebar.open { transform: translateX(0); }
  .main, .main-footer { margin-left: 0; }
  .content { padding: 26px 18px 60px; }
  .tryit-header { flex-wrap: wrap; gap: 10px; }
  .tryit-toolbar { width: 100%; justify-content: flex-end; flex-wrap: wrap; }
  .tryit-editor-wrap { grid-template-columns: 1fr; }
  .tryit-editor-pane { border-right: none; border-bottom: 1px solid var(--border); }
  .page-nav { flex-direction: column; }
  .page-nav-btn.next { flex-direction: row; text-align: left; }
}

@media (max-width: 640px) {
  .topbar { padding: 0 10px; }
  .topbar-logo img { height: 28px; max-width: 130px; }
  .theme-toggle { padding: 7px 10px; font-size: 9px; }
  .topbar-search { display: none; }
  .content { padding: 22px 14px 52px; }
  .main-footer { padding: 16px 14px 26px; }
  .topic-title { font-size: clamp(1.3rem, 7vw, 1.65rem); }
  .topic-subtitle { font-size: 14px; }
  .quiz-box { padding: 18px; }
  .styled-table { display: block; overflow-x: auto; white-space: nowrap; }
}