@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500&display=swap');

/* ===== Design Tokens ===== */
:root {
  --kasi-green: #0F8C55;
  --kasi-green-light: #0BBF6A;
  --kasi-gradient: linear-gradient(135deg, #0F8C55, #0BBF6A);
  --kasi-gradient-subtle: linear-gradient(135deg, rgba(15,140,85,0.08), rgba(11,191,106,0.08));

  --bg-primary: #fafbfc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f3f5f7;
  --bg-code: #0d1117;
  --bg-code-inline: rgba(15,140,85,0.08);

  --text-primary: #1a1f36;
  --text-secondary: #4e5d78;
  --text-tertiary: #8492a6;
  --text-code: #e6edf3;
  --text-link: #0F8C55;

  --border-primary: #e3e8ee;
  --border-secondary: #edf0f4;
  --border-focus: rgba(15,140,85,0.4);

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
  --shadow-focus: 0 0 0 3px rgba(15,140,85,0.15);

  --sidebar-w: 280px;
  --header-h: 64px;
  --content-max-w: 820px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;

  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;

  /* Callout colors */
  --info-bg: rgba(2,132,199,0.06);
  --info-border: rgba(2,132,199,0.25);
  --info-icon: #0284c7;
  --warn-bg: rgba(234,179,8,0.06);
  --warn-border: rgba(234,179,8,0.25);
  --warn-icon: #ca8a04;
  --danger-bg: rgba(239,68,68,0.06);
  --danger-border: rgba(239,68,68,0.25);
  --danger-icon: #dc2626;
  --tip-bg: rgba(15,140,85,0.06);
  --tip-border: rgba(15,140,85,0.25);
  --tip-icon: #0F8C55;
}

[data-theme="dark"] {
  --bg-primary: #0a0e1a;
  --bg-secondary: #111827;
  --bg-tertiary: #1a2035;
  --bg-code: #030712;
  --bg-code-inline: rgba(15,140,85,0.15);

  --text-primary: #f0f4f8;
  --text-secondary: #a0aec0;
  --text-tertiary: #6b7a90;
  --text-link: #0BBF6A;

  --border-primary: #1e293b;
  --border-secondary: #1a2035;
  --border-focus: rgba(11,191,106,0.4);

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.3);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.4);
  --shadow-focus: 0 0 0 3px rgba(11,191,106,0.2);

  --info-bg: rgba(2,132,199,0.1);
  --warn-bg: rgba(234,179,8,0.1);
  --danger-bg: rgba(239,68,68,0.1);
  --tip-bg: rgba(15,140,85,0.1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

::selection {
  background-color: rgba(15,140,85,0.2);
  color: var(--text-primary);
}

/* ===== Header ===== */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-h);
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  z-index: 1000;
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
}

[data-theme="light"] header { background: rgba(255,255,255,0.85); }
[data-theme="dark"] header { background: rgba(17,24,39,0.85); }

.header-left {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

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

.header-logo img.logo-icon {
  width: 28px;
  height: 28px;
  border: none;
  background: none;
  padding: 0;
  margin: 0;
  border-radius: 6px;
  object-fit: contain;
}

.header-logo img.logo-wordmark {
  height: 26px;
  width: auto;
  border: none;
  background: none;
  padding: 0;
  margin: 0;
  object-fit: contain;
  display: none; /* Hide duplicate since it's the same PNG */
}

.header-divider {
  width: 1px;
  height: 24px;
  background-color: var(--border-primary);
  margin: 0 0.3rem;
}

.header-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: -0.01em;
}

.badge-version {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--kasi-green);
  background: var(--kasi-gradient-subtle);
  padding: 0.125rem 0.5rem;
  border-radius: 100px;
  border: 1px solid rgba(15,140,85,0.15);
  letter-spacing: 0.02em;
}

.header-search {
  position: relative;
  width: 380px;
  max-width: 100%;
}

.search-input {
  width: 100%;
  padding: 0.5rem 1rem 0.5rem 2.4rem;
  border-radius: 8px;
  border: 1px solid var(--border-primary);
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  outline: none;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  transition: all var(--transition-fast);
}

.search-input::placeholder { color: var(--text-tertiary); }
.search-input:focus {
  border-color: var(--kasi-green);
  box-shadow: var(--shadow-focus);
  background-color: var(--bg-secondary);
}

.search-icon {
  position: absolute;
  left: 0.8rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-tertiary);
  pointer-events: none;
}

.search-shortcut {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.7rem;
  font-family: var(--font-sans);
  color: var(--text-tertiary);
  background: var(--bg-secondary);
  border: 1px solid var(--border-primary);
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  pointer-events: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.icon-btn {
  background: none;
  border: 1px solid transparent;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.45rem;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
}

.icon-btn:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--border-primary);
}

.github-link {
  text-decoration: none;
  display: flex;
}

/* ===== Page Layout ===== */
.page-container {
  display: flex;
  margin-top: var(--header-h);
  min-height: calc(100vh - var(--header-h));
}

/* ===== Sidebar ===== */
aside.sidebar {
  width: var(--sidebar-w);
  height: calc(100vh - var(--header-h));
  position: fixed;
  left: 0;
  top: var(--header-h);
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border-primary);
  overflow-y: auto;
  padding: 1.25rem 0.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  transition: transform var(--transition-normal);
}

.sidebar-section {
  margin-bottom: 0.5rem;
}

.sidebar-section-title {
  text-transform: uppercase;
  font-size: 0.675rem;
  font-weight: 700;
  color: var(--text-tertiary);
  letter-spacing: 0.08em;
  padding: 0.5rem 0.75rem 0.35rem;
  user-select: none;
}

.menu-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.menu-item-link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 500;
  transition: all var(--transition-fast);
  cursor: pointer;
  position: relative;
}

.menu-item-link svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  border-radius: 0;
}

.menu-item-link:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

.menu-item-link.active {
  background: var(--kasi-gradient-subtle);
  color: var(--kasi-green);
  font-weight: 600;
}

.menu-item-link.active::before {
  content: '';
  position: absolute;
  left: 0;
  top: 6px;
  bottom: 6px;
  width: 3px;
  border-radius: 0 3px 3px 0;
  background: var(--kasi-gradient);
}

/* Sidebar footer */
.sidebar-footer {
  margin-top: auto;
  padding: 1rem 0.75rem;
  border-top: 1px solid var(--border-secondary);
}

.sidebar-footer-text {
  font-size: 0.7rem;
  color: var(--text-tertiary);
  line-height: 1.5;
}

/* ===== Main Content ===== */
main.main-content {
  margin-left: var(--sidebar-w);
  flex: 1;
  padding: 2rem 3rem 4rem;
  max-width: calc(var(--content-max-w) + 6rem);
}

/* Breadcrumbs */
.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  color: var(--text-tertiary);
  margin-bottom: 1.75rem;
}

.breadcrumbs a {
  color: var(--text-tertiary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.breadcrumbs .separator {
  color: var(--border-primary);
}

/* ===== Articles ===== */
article.doc-article { display: none; }
article.doc-article.active { display: block; animation: fadeIn 0.3s ease; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Article header/meta */
.article-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-secondary);
}

.article-badges {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.article-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.article-badge svg {
  width: 12px;
  height: 12px;
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  border-radius: 0;
}

.badge-reading { background: var(--info-bg); color: var(--info-icon); border: 1px solid var(--info-border); }
.badge-level-beginner { background: var(--tip-bg); color: var(--tip-icon); border: 1px solid var(--tip-border); }
.badge-level-intermediate { background: var(--warn-bg); color: var(--warn-icon); border: 1px solid var(--warn-border); }
.badge-level-advanced { background: var(--danger-bg); color: var(--danger-icon); border: 1px solid var(--danger-border); }
.badge-updated { background: var(--bg-tertiary); color: var(--text-tertiary); border: 1px solid var(--border-primary); }

/* Typography */
h1 {
  font-family: var(--font-sans);
  font-size: 2.25rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
  letter-spacing: -0.03em;
  line-height: 1.2;
  color: var(--text-primary);
}

.article-description {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.6;
  max-width: 640px;
}

h2 {
  font-family: var(--font-sans);
  font-size: 1.5rem;
  font-weight: 700;
  margin: 3rem 0 1rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  padding-top: 1rem;
  border-top: 1px solid var(--border-secondary);
}

h2:first-of-type {
  border-top: none;
  padding-top: 0;
}

h3 {
  font-family: var(--font-sans);
  font-size: 1.15rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  color: var(--text-primary);
}

h4 {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 700;
  margin: 1.5rem 0 0.5rem;
  color: var(--kasi-green);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
  font-size: 0.925rem;
  line-height: 1.75;
}

ul, ol {
  margin-bottom: 1rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.4rem;
  font-size: 0.925rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

li strong {
  color: var(--text-primary);
}

hr {
  border: 0;
  height: 1px;
  background: var(--border-secondary);
  margin: 2.5rem 0;
}

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

a:hover { color: var(--kasi-green-light); }

/* ===== Callout Banners ===== */
.banner {
  display: flex;
  gap: 0.85rem;
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  margin: 1.25rem 0;
  font-size: 0.9rem;
  border-left: 4px solid transparent;
  line-height: 1.65;
}

.banner p { margin-bottom: 0; }

.banner-info {
  background: var(--info-bg);
  border-left-color: var(--info-icon);
}

.banner-info .banner-icon { color: var(--info-icon); }

.banner-warning {
  background: var(--warn-bg);
  border-left-color: var(--warn-icon);
}

.banner-warning .banner-icon { color: var(--warn-icon); }

.banner-danger {
  background: var(--danger-bg);
  border-left-color: var(--danger-icon);
}

.banner-danger .banner-icon { color: var(--danger-icon); }

.banner-tip {
  background: var(--tip-bg);
  border-left-color: var(--tip-icon);
}

.banner-tip .banner-icon { color: var(--tip-icon); }

.banner-icon {
  flex-shrink: 0;
  margin-top: 1px;
}

.banner-icon svg {
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  border-radius: 0;
}

/* ===== Code Blocks ===== */
pre {
  background: var(--bg-code);
  border-radius: var(--radius-md);
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  margin: 1rem 0 1.5rem;
  position: relative;
  border: 1px solid rgba(255,255,255,0.06);
}

pre code {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.65;
  color: var(--text-code);
  background: none;
  border: none;
  padding: 0;
  border-radius: 0;
}

/* Language label */
pre::before {
  content: attr(data-lang);
  position: absolute;
  top: 0.5rem;
  left: 1rem;
  font-size: 0.65rem;
  font-family: var(--font-sans);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: rgba(255,255,255,0.3);
  pointer-events: none;
}

pre[data-lang]::before { display: block; }

/* Inline code */
p code, li code, td code {
  background: var(--bg-code-inline);
  color: var(--kasi-green);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  border: 1px solid rgba(15,140,85,0.12);
}

/* Copy button */
.copy-btn {
  position: absolute;
  top: 0.6rem;
  right: 0.6rem;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius-sm);
  padding: 0.35rem;
  color: rgba(255,255,255,0.4);
  cursor: pointer;
  transition: all var(--transition-fast);
  opacity: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.copy-btn svg {
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  border-radius: 0;
}

pre:hover .copy-btn { opacity: 1; }
.copy-btn:hover {
  background: rgba(255,255,255,0.12);
  color: rgba(255,255,255,0.8);
}

/* ===== Tables ===== */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.25rem 0;
  font-size: 0.875rem;
}

th {
  background: var(--bg-tertiary);
  font-weight: 600;
  text-align: left;
  padding: 0.65rem 1rem;
  border-bottom: 2px solid var(--border-primary);
  color: var(--text-primary);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

td {
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--border-secondary);
  color: var(--text-secondary);
}

tr:hover td {
  background: var(--bg-tertiary);
}

/* ===== On this page (TOC) ===== */
.toc-sidebar {
  position: fixed;
  right: 2rem;
  top: calc(var(--header-h) + 2rem);
  width: 200px;
  font-size: 0.75rem;
}

.toc-title {
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  margin-bottom: 0.75rem;
  font-size: 0.65rem;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  border-left: 2px solid var(--border-secondary);
}

.toc-list li {
  margin: 0;
  font-size: 0.75rem;
}

.toc-list a {
  display: block;
  padding: 0.3rem 0 0.3rem 0.75rem;
  color: var(--text-tertiary);
  text-decoration: none;
  transition: all var(--transition-fast);
  border-left: 2px solid transparent;
  margin-left: -2px;
}

.toc-list a:hover {
  color: var(--text-link);
}

.toc-list a.active {
  color: var(--kasi-green);
  border-left-color: var(--kasi-green);
  font-weight: 600;
}

/* ===== Footer ===== */
.doc-footer {
  margin-left: var(--sidebar-w);
  padding: 2rem 3rem;
  border-top: 1px solid var(--border-secondary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-tertiary);
}

.doc-footer a {
  color: var(--text-tertiary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.doc-footer a:hover { color: var(--text-link); }

/* ===== Scrollbars ===== */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-primary); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-tertiary); }

/* ===== SVG global reset (override browser SVG styling for inline icons) ===== */
svg:not(.diagram-svg) {
  background-color: transparent;
  border: none;
  border-radius: 0;
  padding: 0;
  margin: 0;
}

/* ===== Feature Cards (Welcome page) ===== */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin: 1.5rem 0;
}

.feature-card {
  padding: 1.25rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-primary);
  background: var(--bg-secondary);
  transition: all var(--transition-normal);
}

.feature-card:hover {
  border-color: var(--kasi-green);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.feature-card-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.75rem;
  font-size: 1.25rem;
}

.feature-card h3 {
  margin: 0 0 0.35rem;
  font-size: 0.95rem;
}

.feature-card p {
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.55;
}

/* ===== Platform badges ===== */
.platform-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.7rem;
  border-radius: 100px;
  font-size: 0.78rem;
  font-weight: 600;
  margin-right: 0.5rem;
}

.platform-whatsapp { background: rgba(37,211,102,0.1); color: #25d366; }
.platform-telegram { background: rgba(0,136,204,0.1); color: #0088cc; }
.platform-instagram { background: rgba(225,48,108,0.1); color: #e1306c; }
.platform-facebook { background: rgba(24,119,242,0.1); color: #1877f2; }

/* ===== Mobile Menu Button ===== */
.menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 0.45rem;
  border-radius: var(--radius-sm);
}

.menu-btn svg {
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  border-radius: 0;
}

/* ===== Mobile Overlay ===== */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 999;
  backdrop-filter: blur(4px);
}

.sidebar-overlay.active { display: block; }

/* ===== Responsive ===== */
@media (max-width: 1200px) {
  .toc-sidebar { display: none; }
}

@media (max-width: 900px) {
  .menu-btn { display: flex; }
  
  header { padding: 0 1rem; }
  
  .header-search { display: none; }
  .badge-version { display: none; }
  
  aside.sidebar {
    transform: translateX(-100%);
    width: 280px;
    z-index: 1001;
    box-shadow: var(--shadow-lg);
  }
  
  aside.sidebar.open { transform: translateX(0); }
  
  main.main-content {
    margin-left: 0;
    padding: 1.5rem 1.25rem 3rem;
  }
  
  .doc-footer {
    margin-left: 0;
    padding: 1.5rem 1.25rem;
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }
  
  h1 { font-size: 1.75rem; }
  
  .feature-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  header { gap: 0.25rem; }
  .header-logo img.logo-wordmark { display: none; }
  .header-divider { display: none; }
  .header-label { font-size: 0.8rem; }
}