/* PenguinPulse - Modern CSS */

/* CSS Variables for theming */
:root {
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-primary-dark: #1d4ed8;
  --color-secondary: #06b6d4;
  --color-accent: #8b5cf6;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-text-light: #94a3b8;
  --color-bg: #f8fafc;
  --color-bg-secondary: #f1f5f9;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;
  --color-code-bg: #f8fafc;
  --color-code-text: #e11d48;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-full: 9999px;
}

/* Dark mode */
@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #3b82f6;
    --color-primary-light: #60a5fa;
    --color-primary-dark: #2563eb;
    --color-secondary: #22d3ee;
    --color-accent: #a78bfa;
    --color-text: #f1f5f9;
    --color-text-muted: #cbd5e1;
    --color-text-light: #94a3b8;
    --color-bg: #0f172a;
    --color-bg-secondary: #1e293b;
    --color-surface: #1e293b;
    --color-border: #334155;
    --color-border-light: #1e293b;
    --color-code-bg: #0f172a;
    --color-code-text: #fb7185;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
  }
}

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

html, body {
  overflow-x: hidden;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Header Styles */
header {
  text-align: center;
  padding: 3rem 0 2.5rem;
  margin-bottom: 3rem;
}

header h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
  letter-spacing: -0.03em;
  color: var(--color-primary);
}

header h1 a {
  color: var(--color-primary);
  text-decoration: none;
  transition: opacity 0.2s ease;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.logo-icon {
  height: 1em;
  width: auto;
  vertical-align: middle;
}

header h1 a:hover {
  opacity: 0.7;
  text-decoration: none;  /* Prevent global a:hover from adding underline */
}

header p {
  color: var(--color-text-muted);
  font-size: 1.125rem;
  font-weight: 500;
  letter-spacing: 0.01em;
}

/* Main Content */
main {
  background: transparent;
  padding: 0;
  margin-bottom: 3rem;
}

/* Article Styles */
article {
  margin-bottom: 3rem;
}

article.preview {
  padding: 1.75rem;
  margin-bottom: 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  transition: all 0.3s ease;
  position: relative;
}

article.preview:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

article.preview::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(180deg, var(--color-primary), var(--color-secondary));
  border-radius: var(--radius-md) 0 0 var(--radius-md);
  opacity: 0;
  transition: opacity 0.3s ease;
}

article.preview:hover::before {
  opacity: 1;
}

article h1, article h2 {
  margin-bottom: 0.75rem;
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -0.02em;
}

article h1 {
  font-size: 2.25rem;
  color: var(--color-text);
  margin-bottom: 1rem;
}

article h2 {
  font-size: 1.5rem;
  color: var(--color-text);
}

article h2 a {
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.2s ease;
  position: relative;
}

article h2 a:hover {
  color: var(--color-primary);
}

/* Time */
time {
  display: inline-block;
  color: var(--color-text-light);
  font-size: 0.875rem;
  font-weight: 500;
  margin-bottom: 1.25rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
}

/* Tags */
.tags {
  margin: 1.5rem 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 0.375rem 0.875rem;
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s ease;
  border: 1px solid var(--color-border);
  letter-spacing: 0.01em;
  background: var(--color-bg-secondary);
  color: var(--color-text-muted);
}

.tag:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

/* Summary */
.summary p {
  margin-bottom: 1.25rem;
  line-height: 1.8;
  color: var(--color-text);
  font-size: 1.0625rem;
}

/* Blockquote */
blockquote {
  margin: 1.75rem 0;
  padding: 1.25rem 1.5rem;
  background: var(--color-bg-secondary);
  border-left: 4px solid var(--color-primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-style: italic;
  color: var(--color-text-muted);
}

blockquote p {
  margin-bottom: 0.75rem;
}

blockquote p:last-child {
  margin-bottom: 0;
}

/* Code */
code {
  font-family: "SF Mono", "Monaco", "Inconsolata", "Fira Code", "Courier New", monospace;
  background: var(--color-code-bg);
  color: var(--color-code-text);
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  font-size: 0.875em;
  font-weight: 500;
  border: 1px solid var(--color-border);
}

/* Override code styling in headings and previews - must come after general code rule */
h1 code, h2 code, h3 code, h4 code, h5 code, h6 code,
article h1 code, article h2 code, article.preview h2 code {
  font-family: inherit !important;
  color: inherit !important;
  background: transparent !important;
  border: none !important;
  padding: 0 !important;
  font-size: inherit !important;
  font-weight: inherit !important;
}

article.preview code {
  font-weight: 600;
}

pre {
  margin: 1.75rem 0;
  padding: 1.25rem;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  overflow-x: auto;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

pre code {
  background: none;
  padding: 0;
  color: var(--color-text);
  font-size: 0.875rem;
  line-height: 1.6;
  border: none;
}

/* Lists */
ul {
  margin: 1.5rem 0;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.625rem;
  line-height: 1.7;
  color: var(--color-text);
}

li::marker {
  color: var(--color-primary);
}

/* Links */
a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-primary-dark);
  text-decoration: underline;
}

.read-more {
  display: inline-flex;
  align-items: center;
  margin-top: 1rem;
  font-weight: 600;
  color: var(--color-primary);
  transition: all 0.2s ease;
  font-size: 0.9375rem;
}

.read-more:hover {
  color: var(--color-primary-dark);
  transform: translateX(4px);
}

/* Social Share Buttons */
.share-buttons {
  margin: 2rem 0 1.5rem 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
}

.share-button {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.625rem 1rem;
  background: var(--color-surface);
  text-decoration: none;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 0.875rem;
  transition: all 0.2s ease;
  border: 1.5px solid;
  box-shadow: var(--shadow-sm);
}

.share-button:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
  text-decoration: none;
}

.share-button:active {
  transform: translateY(0);
}

/* Hacker News button */
.hn-button {
  color: #ff6600;
  border-color: #ff6600;
}

.hn-button:hover {
  background: #ff6600;
  color: #ffffff;
}

/* Twitter/X button */
.twitter-button {
  color: #000000;
  border-color: #000000;
}

.twitter-button:hover {
  background: #000000;
  color: #ffffff;
}

@media (prefers-color-scheme: dark) {
  .twitter-button {
    color: #ffffff;
    border-color: #ffffff;
  }

  .twitter-button:hover {
    background: #ffffff;
    color: #000000;
  }
}

/* LinkedIn button */
.linkedin-button {
  color: #0a66c2;
  border-color: #0a66c2;
}

.linkedin-button:hover {
  background: #0a66c2;
  color: #ffffff;
}

/* Mobile: stack buttons vertically */
@media (max-width: 480px) {
  .share-buttons {
    flex-direction: column;
    align-items: stretch;
  }

  .share-button {
    width: 100%;
    justify-content: center;
  }
}

/* Newsletter Signup */
.newsletter-signup {
  margin: 3rem 0 2rem 0;
  padding: 2rem;
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  text-align: center;
}

/* .newsletter-signup.compact {
  padding: 1rem;
  margin: 2rem 0;
} */

.newsletter-signup h2 {
  margin-bottom: 0.75rem;
  font-size: 1.5rem;
  color: var(--color-text);
}

.newsletter-signup p {
  margin-bottom: 1.5rem;
  color: var(--color-text-muted);
  font-size: 1rem;
  line-height: 1.6;
}

/* Center EmailOctopus form content */
.newsletter-signup > * {
  margin-left: auto;
  margin-right: auto;
}

.newsletter-signup form,
.newsletter-signup div {
  display: block;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.newsletter-form {
  display: flex;
  gap: 0.75rem;
  max-width: 500px;
  margin: 0 auto 1rem auto;
}

.newsletter-input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 0.9375rem;
  font-family: inherit;
  transition: all 0.2s ease;
}

.newsletter-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.newsletter-input::placeholder {
  color: var(--color-text-light);
}

.newsletter-button {
  padding: 0.75rem 1.5rem;
  background: var(--color-primary);
  color: #ffffff;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: inherit;
}

.newsletter-button:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.newsletter-button:active {
  transform: translateY(0);
}

.newsletter-note {
  margin-bottom: 0;
  font-size: 0.8125rem;
  color: var(--color-text-light);
}

/* Mobile: stack newsletter form */
@media (max-width: 480px) {
  .newsletter-signup {
    padding: 1.5rem;
  }

  .newsletter-form {
    flex-direction: column;
  }

  .newsletter-input,
  .newsletter-button {
    width: 100%;
  }
}

/* Footer */
footer {
  text-align: center;
  padding: 2rem 1rem;
  color: var(--color-text-light);
  font-size: 0.875rem;
  border-top: 1px solid var(--color-border);
  margin-top: 3rem;
}

footer p {
  margin-bottom: 0.5rem;
}

footer a {
  color: var(--color-primary);
  font-weight: 600;
  transition: color 0.2s ease;
}

footer a:hover {
  color: var(--color-primary);
  text-decoration: none;
}

/* Responsive Design */
@media (max-width: 768px) {
  body {
    padding: 1rem;
    font-size: 15px;
  }

  main {
    padding: 0;
    margin-bottom: 2rem;
  }

  header {
    padding: 2rem 0 1.5rem;
    margin-bottom: 2rem;
  }

  header h1 {
    font-size: 2.25rem;
  }

  header p {
    font-size: 1rem;
  }

  article h1 {
    font-size: 1.75rem;
  }

  article h2 {
    font-size: 1.25rem;
  }

  article.preview {
    padding: 1.25rem;
  }

  .tags {
    gap: 0.375rem;
  }

  .tag {
    font-size: 0.75rem;
    padding: 0.3rem 0.75rem;
  }
}

@media (max-width: 480px) {
  body {
    padding: 0.75rem;
  }

  main {
    padding: 0;
  }

  header h1 {
    font-size: 1.875rem;
  }

  article.preview {
    padding: 1rem;
  }
}

/* Tooltip styles for technical term definitions */
.tooltip-term {
  position: relative;
  text-decoration: underline;
  text-decoration-color: var(--color-primary);
  text-decoration-thickness: 1px;
  text-underline-offset: 2px;
  cursor: help;
  color: inherit;
}

.tooltip-term::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  padding: 0.625rem 0.875rem;
  background: var(--color-surface);
  color: var(--color-text);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  font-size: 0.875rem;
  line-height: 1.5;
  white-space: normal;
  max-width: 280px;
  width: max-content;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
  pointer-events: none;
  font-weight: 400;
}

.tooltip-term:hover::after {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(-4px);
}

/* Arrow for tooltip */
.tooltip-term::before {
  content: '';
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(4px);
  border: 6px solid transparent;
  border-top-color: var(--color-border);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
  z-index: 1001;
}

.tooltip-term:hover::before {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

/* Mobile: tap to toggle tooltip */
@media (max-width: 768px) {
  .tooltip-term::after {
    left: 0;
    right: 0;
    transform: translateY(-8px);
    margin: 0 auto;
  }

  .tooltip-term::before {
    left: 50%;
    transform: translateX(-50%) translateY(4px);
  }

  .tooltip-term:hover::after {
    transform: translateY(-4px);
  }

  .tooltip-term:hover::before {
    transform: translateX(-50%) translateY(0);
  }
}

/* Ensure tooltips don't overflow viewport on small screens */
@media (max-width: 480px) {
  .tooltip-term::after {
    max-width: calc(100vw - 2rem);
    font-size: 0.8125rem;
  }
}

/* ============================================================
   PAGINATION
   ============================================================ */

.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  margin: 3rem 0;
  padding: 1.5rem 0;
  border-top: 1px solid var(--color-border);
}

.pagination-link {
  display: inline-block;
  padding: 0.5rem 1rem;
  text-decoration: none;
  color: var(--color-primary);
  font-weight: 500;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.pagination-link:hover {
  background-color: var(--color-bg-secondary);
  transform: translateY(-1px);
}

.pagination-link.disabled {
  color: var(--color-text-light);
  cursor: not-allowed;
  opacity: 0.5;
}

.pagination-link.disabled:hover {
  background-color: transparent;
  transform: none;
}

.page-info {
  color: var(--color-text);
  font-weight: 500;
}

@media (max-width: 640px) {
  .pagination {
    gap: 1rem;
  }

  .pagination-link {
    padding: 0.4rem 0.75rem;
    font-size: 0.875rem;
  }

  .page-info {
    font-size: 0.875rem;
  }
}

/* ============================================================
   ARCHIVE PAGES
   ============================================================ */

.archive-header {
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--color-border);
}

.archive-header h1 {
  margin-bottom: 0.5rem;
}

.archive-header p {
  margin-top: 0.5rem;
}

.archive-header a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
}

.archive-header a:hover {
  text-decoration: underline;
}