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

/* ==========================================================================
   1. MODERN CSS RESET & BOX SIZING
   ========================================================================== */

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

/* Prevent font size inflation on mobile devices */
html {
  -webkit-text-size-adjust: 100%;
  tab-size: 4;
  scroll-behavior: smooth;
}

/* Root variables for typography, colors, and layout rhythm */
:root {
  /* Fixed blue theme for consistent branding */
  --bg-primary: #0f172a;
  --bg-surface: #1e293b;
  --bg-subtle: #334155;
  --border-color: #334155;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --accent: #38bdf8;
  --accent-hover: #7dd3fc;

  /* Typography Scale */
  --font-sans:
    "JetBrains Mono", "JetBrains Mono Nerd", "JetBrainsMono Nerd Font",
    ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  --font-mono: var(--font-sans);

  --text-xs: 0.8125rem; /* 13px */
  --text-sm: 0.9375rem; /* 15px */
  --text-base: 1.0625rem; /* 17px */
  --text-lg: 1.25rem; /* 20px */
  --text-xl: 1.625rem; /* 26px */
  --text-2xl: 2.125rem; /* 34px */

  /* Layout Spacing */
  --space-2xs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;

  --max-width: 1080px;
  --radius-sm: 6px;
  --radius-md: 10px;
}

/* ==========================================================================
   2. TYPOGRAPHY & BASE STYLES
   ========================================================================== */

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.8;
  color: var(--text-primary);
  background-color: var(--bg-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Headings with tight line-height */
h1,
h2,
h3,
h4,
h5,
h6 {
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--space-xs);
}

h1 {
  font-size: clamp(2rem, 4vw, 3rem);
}
h2 {
  font-size: clamp(1.2rem, 2vw, 1.8rem);
  margin-top: 0;
}
h3 {
  font-size: var(--text-lg);
}

p {
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
}

/* Links */
a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 0.15s ease-in-out;
}

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

/* Code & Preformatted Text */
code,
pre {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

code {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  background-color: var(--bg-subtle);
  color: var(--accent);
  padding: 0.15em 0.4em;
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

hr.divider {
  border: 0;
  height: 1px;
  background-color: var(--border-color);
  margin: var(--space-md) 0;
}

/* Form controls ignore the body font unless told to inherit it */
button,
input,
select,
textarea {
  font-family: inherit;
}

/* Media Elements Reset */
img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

/* ==========================================================================
   3. LAYOUT & GRID SYSTEM
   ========================================================================== */

/* Main Page Container */
.site-header,
#main-content,
.site-footer {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-md);
  padding-right: var(--space-md);
}

#main-content {
  flex: 1;
  padding-top: var(--space-lg);
  padding-bottom: var(--space-xl);
}

/* Flexible Layout Utilities */
.grid {
  display: grid;
  gap: var(--space-md);
}

/* Auto-fit Responsive Grid for Cards & Showcase items */
.grid-auto {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-md);
}

/* Flex Container Utilities */
.flex {
  display: flex;
  gap: var(--space-sm);
}

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

/* ==========================================================================
   4. NAVIGATION & FOOTER
   ========================================================================== */

.site-header {
  padding-top: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.site-title {
  font-weight: 700;
  font-size: var(--text-lg);
  color: var(--text-primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: var(--space-md);
}

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--accent);
}

.site-footer {
  padding-top: var(--space-md);
  padding-bottom: var(--space-md);
  border-top: 1px solid var(--border-color);
  font-size: var(--text-xs);
  color: var(--text-secondary);
  text-align: center;
}

/* ==========================================================================
   5. UI COMPONENTS (Buttons & Focus Cards)
   ========================================================================== */

.focus-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-top: var(--space-sm);
}

.btn {
  display: inline-block;
  padding: var(--space-xs) var(--space-sm);
  background-color: var(--accent);
  color: #ffffff;
  border-radius: var(--radius-sm);
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: 600;
  transition: background-color 0.15s ease-in-out;
}

.btn:hover {
  background-color: var(--accent-hover);
  color: #ffffff;
}

.page-shell {
  display: block;
}

.essay {
  display: block;
}

.about-hero {
  padding-top: var(--space-xs);
  padding-bottom: var(--space-lg);
}

.eyebrow {
  display: inline-block;
  margin-bottom: var(--space-sm);
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: var(--text-xs);
  font-weight: 700;
}

.essay-section {
  margin-top: 2.25rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
}

.essay-section h2 {
  margin-bottom: 1rem;
  font-size: clamp(1.2rem, 2vw, 1.8rem);
}

.essay-section p {
  margin-bottom: 1.4rem;
}

.bullet-list {
  list-style: "- ";
  padding-left: 1.5rem;
  display: grid;
  gap: 0.8rem;
}

.bullet-list li {
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 0.2rem;
}

.final-section {
  margin-bottom: var(--space-lg);
}

@media (max-width: 720px) {
  .essay-section {
    margin-top: 1.5rem;
  }

  .bullet-list {
    padding-left: 1.2rem;
  }
}

/* ==========================================================================
   6. Lectures page styles
========================================================================== */
.current-course,
.curriculum-roadmap {
  max-width: 900px;
  margin: 2rem auto;
  padding: 0 1rem;
}

.course-highlight-card,
.roadmap-item {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 8px;
  padding: 2rem;
  text-align: left; /* Cleaner readability for technical text */
  display: flex;
  flex-direction: column;
  text-align: center;
  margin-top: 1rem;
}
.course-highlight-card h3 {
  font-size: 1.25rem;
  color: #38bdf8;
  margin-bottom: 0.75rem;
}

.course-highlight-card p {
  margin-bottom: 1rem;
  line-height: 1.5;
  color: #cbd5e1;
}

.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 2rem;
  align-items: stretch;
}
/* Distinct separation for the card heading */
.roadmap-item h3 {
  font-size: 1.15rem;
  color: #38bdf8; /* Accent color to pop against body text */
  margin-bottom: 0.75rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08); /* Clean divider line */
}

.roadmap-item p {
  font-size: 0.95rem;
  line-height: 1.5;
  color: #cbd5e1;
  margin: 0;
}
.btn-watch {
  display: inline-block;
  margin-top: 1rem;
  padding: 0.5rem 1rem;
  background: #38bdf8;
  color: #0f172a;
  font-weight: bold;
  border-radius: 4px;
  text-decoration: none;
}

.btn-watch:hover {
  background: #0ea5e9;
}
.content-container {
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

.content-container p.subtitle {
  margin: 0.5rem auto 2rem auto;
  max-width: 600px;
}
.latest-lecture {
  text-align: center; /* Centers inline or inline-block children */
  margin-top: 1.5rem;
}

.btn-watch {
  display: inline-block;
  margin-top: 0.5rem;
  padding: 0.75rem 1.5rem;
  background: #38bdf8;
  color: #0f172a;
  font-weight: bold;
  border-radius: 6px;
  text-decoration: none;
}

.btn-watch:hover {
  background: #0ea5e9;
}

/* ==========================================================================
   7. Projects & Systems page styles
========================================================================== */
/* Centered container modifier for pages like Projects & Lectures */
.content-container.projects-container {
  text-align: center;
}

.content-container.projects-container .projects-grid {
  text-align: left;
  margin-top: 2rem;
}

/* Push action buttons to the bottom of cards consistently */
.roadmap-item .btn-project {
  margin-top: auto;
  text-align: center;
}

/* Footer spacing for nested pages */
.site-footer {
  text-align: center;
  margin-top: 4rem;
}
/* Container that pushes buttons to the bottom and stacks them vertically */
.roadmap-item .card-actions {
  margin-top: auto;
  display: flex;
  flex-direction: column;
  gap: 0.75rem; /* Space between the two buttons */
  padding-top: 1.5rem;
}

/* Primary Button Styling */
.roadmap-item .btn-watch {
  display: block;
  width: 100%;
  text-align: center;
  padding: 0.75rem 1rem;
  background: #38bdf8;
  color: #0f172a;
  font-weight: bold;
  border-radius: 6px;
  text-decoration: none;
  box-sizing: border-box;
}

.roadmap-item .btn-watch:hover {
  background: #0ea5e9;
}

/* Secondary Button Styling for GitHub Repo */
.roadmap-item .btn-secondary {
  background: transparent;
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.4);
}

.roadmap-item .btn-secondary:hover {
  background: rgba(56, 189, 248, 0.1);
  color: #38bdf8;
}
/* ==========================================================================
   8. Case Studies page styles
========================================================================== */
/* Forces a single-column row layout for pages like Case Studies */
/* Optimized full-width container for long-form reading */
.roadmap-grid.single-column-grid {
  grid-template-columns: 1fr;
  max-width: 900px; /* Wider measure for comfortable long-form reading */
  margin-left: auto;
  margin-right: auto;
}

/* Deep card styling for articles / case studies */
.roadmap-item.case-study-card {
  padding: 2.5rem 3rem;
  text-align: left;
}

.case-study-card h3 {
  font-size: 1.5rem;
  color: #38bdf8;
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

/* Structured content blocks inside the long-form card */
.case-study-section {
  margin-bottom: 1.5rem;
}

.case-study-section h4 {
  font-size: 1.1rem;
  color: #f8fafc;
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.case-study-section p {
  font-size: 1.05rem;
  line-height: 1.75; /* Generous line height for extended reading */
  color: #cbd5e1;
  margin: 0;
}

/* Action buttons pinned nicely at the bottom */
.case-study-card .card-actions {
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  flex-direction: row;
  gap: 1rem;
}

.case-study-card .card-actions .btn-watch {
  flex: 1;
}
/* ==========================================================================
   9. Digital Garden page styles
========================================================================== */
/* --- Maggie Appleton Style Essay Layout --- */

/* Updated 2-Column Essay Layout (TOC + Reading Pane) */
.essay-layout-container {
  display: grid;
  grid-template-columns: 240px minmax(0, 800px);
  gap: 4rem;
  max-width: 1150px;
  margin: 3rem auto;
  padding: 0 2rem;
  align-items: start;
  justify-content: center;
}

/* Left TOC Sidebar */
.essay-toc-sidebar {
  position: sticky;
  top: 2rem;
}

.toc-title {
  display: block;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #64748b;
  margin-bottom: 1rem;
  font-weight: 600;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.toc-link {
  display: block;
  padding: 0.5rem 0.75rem;
  color: #94a3b8;
  text-decoration: none;
  border-radius: 4px;
  font-size: 0.95rem;
  transition:
    color 0.2s,
    background 0.2s;
}

.toc-link:hover {
  color: #f8fafc;
  background: rgba(255, 255, 255, 0.03);
}

.toc-link.active {
  color: #38bdf8;
  background: rgba(56, 189, 248, 0.08);
  font-weight: 500;
}

/* Center Main Reading Column */
.essay-main-content {
  text-align: left;
}

.essay-article {
  display: none;
}

.essay-article.active-essay {
  display: block;
}

.essay-header {
  margin-bottom: 2rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.essay-header h1 {
  font-size: clamp(2rem, 3vw, 2.75rem);
  color: #f8fafc;
  margin: 0.75rem 0 0.5rem 0;
  letter-spacing: -0.02em;
}

.essay-meta {
  font-size: 0.9rem;
  color: #64748b;
}

.essay-body p {
  font-size: 1.125rem;
  line-height: 1.8;
  color: #cbd5e1;
  margin-bottom: 1.5rem;
}

/* Right Marginalia Column */
.essay-marginalia {
  position: sticky;
  top: 2rem;
}

.marginalia-box {
  background: rgba(255, 255, 255, 0.02);
  border-left: 2px solid #38bdf8;
  padding: 1.25rem;
  border-radius: 0 6px 6px 0;
}

.marginalia-title {
  display: block;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #38bdf8;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.marginalia-box p {
  font-size: 0.9rem;
  line-height: 1.6;
  color: #94a3b8;
  margin: 0;
}

/* Responsive collapse for tablets and mobile */
@media (max-width: 1100px) {
  .essay-layout-container {
    grid-template-columns: 220px 1fr;
  }
  .essay-marginalia {
    display: none; /* Hide marginalia on mid-size screens */
  }
}

@media (max-width: 768px) {
  .essay-layout-container {
    grid-template-columns: 1fr;
    padding: 0 1rem;
  }
  .essay-toc-sidebar {
    position: static;
    margin-bottom: 2rem;
    background: rgba(255, 255, 255, 0.02);
    padding: 1rem;
    border-radius: 8px;
  }
}