/* ===== Reset & Base ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  font-size: 18px;
  line-height: 1.7;
  color: #1a1a1a;
  background: #ffffff;
}

/* ===== Container ===== */
.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Typography ===== */
h1 {
  font-size: 2.5rem;
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: 1.5rem;
  color: #000;
}

h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 2rem;
  color: #000;
}

h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: #000;
}

p {
  margin-bottom: 1rem;
  color: #4a4a4a;
}

.lead {
  font-size: 1.25rem;
  color: #4a4a4a;
  margin-bottom: 2rem;
}

a {
  color: #000;
  text-decoration: none;
  border-bottom: 1px solid #d1d1d1;
  transition: border-color 0.2s ease;
}

a:hover {
  border-bottom-color: #000;
}

/* ===== Navigation ===== */
nav {
  padding: 2rem 0;
  border-bottom: 1px solid #e5e5e5;
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  z-index: 100;
}

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

.logo {
  font-weight: 600;
  font-size: 1.125rem;
  border: none;
}

.logo:hover {
  border: none;
}

.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-links a {
  font-size: 0.938rem;
  border: none;
  color: #666;
}

.nav-links a:hover {
  color: #000;
  border: none;
}

/* ===== Dropdown ===== */
.dropdown {
  position: relative;
}

.dropdown-toggle {
  cursor: pointer;
  user-select: none;
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  right: 0;
  margin-top: 0.5rem;
  min-width: 140px;
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all 0.2s ease;
  z-index: 1000;
}

.dropdown:hover .dropdown-menu,
.dropdown.active .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-menu a {
  display: block;
  padding: 0.75rem 1rem;
  font-size: 0.938rem;
  color: #666;
  border: none;
  border-bottom: 1px solid #f5f5f5;
  transition: all 0.2s ease;
}

.dropdown-menu a:last-child {
  border-bottom: none;
}

.dropdown-menu a:hover {
  color: #000;
  background: #fafafa;
}

/* ===== Sections ===== */
section {
  padding: 5rem 0;
}

.hero {
  padding: 6rem 0;
}

/* ===== Buttons ===== */
.cta {
  display: flex;
  gap: 1rem;
  margin-top: 2.5rem;
}

.button,
.button-secondary {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-size: 0.938rem;
  border-radius: 4px;
  border: 1px solid #000;
  transition: all 0.2s ease;
  text-align: center;
}

.button {
  background: #000;
  color: #fff;
  border-bottom: 1px solid #000;
}

.button:hover {
  background: #1a1a1a;
  border-bottom: 1px solid #000;
}

.button-secondary {
  background: #fff;
  color: #000;
  border-bottom: 1px solid #000;
}

.button-secondary:hover {
  background: #f5f5f5;
  border-bottom: 1px solid #000;
}

/* ===== Experience ===== */
#experience {
  background: #fafafa;
}

.experience-item {
  margin-bottom: 3rem;
  padding-bottom: 3rem;
  border-bottom: 1px solid #e5e5e5;
}

.experience-item:last-of-type {
  border-bottom: none;
}

.experience-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 0.5rem;
}

.year {
  font-size: 0.938rem;
  color: #999;
}

.role {
  font-weight: 500;
  color: #666;
  margin-bottom: 0.75rem;
}

.education {
  margin-top: 4rem;
  padding-top: 3rem;
  border-top: 1px solid #e5e5e5;
}

.education h3 {
  margin-bottom: 1.5rem;
}

.education p {
  margin-bottom: 0.75rem;
}

/* ===== Writing ===== */
#writing {
  border-top: 1px solid #e5e5e5;
}

.posts {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.post {
  display: block;
  padding-bottom: 2rem;
  border-bottom: 1px solid #e5e5e5;
}

.post:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.post-date {
  font-size: 0.875rem;
  color: #999;
  display: block;
  margin-bottom: 0.5rem;
}

.post-title {
  font-size: 1.25rem;
  font-weight: 500;
  color: #1a1a1a;
  margin: 0;
}

.post:hover .post-title {
  color: #000;
}

/* ===== Contact ===== */
.contact-links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2rem;
}

.contact-links a {
  font-size: 1.125rem;
}

/* ===== Footer ===== */
footer {
  padding: 3rem 0;
  border-top: 1px solid #e5e5e5;
  text-align: center;
}

footer p {
  font-size: 0.875rem;
  color: #999;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  body {
    font-size: 16px;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.375rem;
  }

  .lead {
    font-size: 1.125rem;
  }

  section {
    padding: 3rem 0;
  }

  .hero {
    padding: 4rem 0;
  }

  .cta {
    flex-direction: column;
  }

  .button,
  .button-secondary {
    width: 100%;
  }

  .experience-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .year {
    margin-top: 0.25rem;
  }

  .nav-links {
    gap: 1.5rem;
  }

  .nav-links a {
    font-size: 0.875rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  nav .container {
    flex-direction: row;
    align-items: center;
    gap: 0;
  }

  .logo {
    flex-shrink: 0;
  }

  .nav-links {
    margin-left: auto;
    width: auto;
  }
}


/* ===== Blackjack Game ===== */
.bj-game {
  min-height: 100svh;
  background: #f5f5f5;
}

.bj-container {
  max-width: 600px;
  margin: 0 auto;
  width: 100%;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  background: #fff;
}

/* Top Bar */
.bj-topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
  background: #000;
  color: #fff;
}

.bj-balance {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.bj-balance-amount {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
}

.bj-balance-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  opacity: 0.7;
}

.bj-stats-toggle {
  background: rgba(255, 255, 255, 0.1);
  border: none;
  color: #fff;
  padding: 0.5rem 0.75rem;
  border-radius: 20px;
  font-size: 0.875rem;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.2s;
}

.bj-stats-toggle:hover {
  background: rgba(255, 255, 255, 0.15);
}

/* Playing Area */
.bj-playing-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  padding: 1.5rem 1rem;
  background: linear-gradient(180deg, #fafafa 0%, #f5f5f5 100%);
  min-height: 0;
}

.bj-dealer,
.bj-player {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.bj-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  font-weight: 600;
  color: #666;
  padding: 0 0.5rem;
}

.bj-score {
  font-size: 1.25rem;
  color: #000;
}

.bj-cards {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  min-height: 85px;
}

/* Cards */
.card {
  width: 60px;
  height: 84px;
  border: 2px solid #000;
  border-radius: 6px;
  background: #fff;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  position: relative;
  flex-shrink: 0;
  transition: transform 0.2s;
}

.card:hover {
  transform: translateY(-2px);
}

.card.red {
  color: #dc2626;
}

.card-back {
  background: #000;
  color: #fff;
  font-size: 2rem;
}

.card-value {
  position: absolute;
  top: 0.375rem;
  left: 0.375rem;
  font-size: 0.875rem;
  line-height: 1;
}

.card-suit {
  font-size: 2rem;
}

/* Status Message */
.bj-status {
  text-align: center;
  font-size: 1.125rem;
  font-weight: 600;
  color: #000;
  padding: 0.5rem;
  min-height: 2rem;
}

/* Active Hand Highlighting */
.bj-player.active-hand {
  background: rgba(0, 0, 0, 0.03);
  border-radius: 8px;
  padding: 0.75rem;
  margin: -0.75rem;
}

/* Action Area */
.bj-action-area {
  padding: 1.5rem 1.5rem 1rem;
  background: #fff;
  border-top: 1px solid #e5e5e5;
}

/* Betting Controls */
.bj-bet-controls {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.bj-bet-chips {
  display: flex;
  gap: 0.5rem;
  justify-content: space-between;
}

.bj-chip {
  flex: 1;
  padding: 1rem 0.5rem;
  background: #fff;
  border: 2px solid #000;
  border-radius: 50%;
  font-size: 0.938rem;
  font-weight: 700;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.bj-chip:hover {
  background: #000;
  color: #fff;
  transform: scale(1.05);
}

.bj-chip:active {
  transform: scale(0.95);
}

.bj-bet-display {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 1rem;
  background: #fafafa;
  border-radius: 8px;
}

.bj-bet-label {
  font-size: 0.938rem;
  font-weight: 600;
  color: #666;
}

.bj-bet-display input {
  flex: 1;
  background: #fff;
  border: 2px solid #e5e5e5;
  border-radius: 6px;
  padding: 0.75rem;
  font-size: 1.125rem;
  font-weight: 700;
  font-family: inherit;
  text-align: center;
}

.bj-bet-clear {
  background: none;
  border: none;
  color: #666;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  padding: 0.5rem;
}

.bj-bet-clear:hover {
  color: #000;
}

/* Play Controls */
.bj-play-controls {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.bj-main-actions {
  display: flex;
  gap: 0.75rem;
}

.bj-extra-actions {
  display: flex;
  gap: 0.75rem;
}

/* Action Buttons */
.bj-action-btn {
  flex: 1;
  padding: 1.125rem 1.5rem;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  font-family: inherit;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  min-height: 56px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.bj-action-btn:active {
  transform: scale(0.98);
}

.bj-primary {
  background: #000;
  color: #fff;
}

.bj-primary:hover {
  background: #1a1a1a;
}

.bj-primary:disabled {
  background: #999;
  cursor: not-allowed;
}

.bj-secondary {
  background: #f5f5f5;
  color: #000;
  border: 2px solid #000;
}

.bj-secondary:hover {
  background: #e5e5e5;
}

.bj-outline {
  background: #fff;
  color: #000;
  border: 2px solid #e5e5e5;
}

.bj-outline:hover {
  border-color: #000;
  background: #fafafa;
}

/* Reset Link */
.bj-reset-link {
  background: none;
  border: none;
  color: #999;
  font-size: 0.813rem;
  padding: 1rem;
  text-align: center;
  cursor: pointer;
  font-family: inherit;
}

.bj-reset-link:hover {
  color: #000;
}

/* Mobile Responsive */
@media (max-width: 600px) {
  .bj-topbar {
    padding: 0.875rem 1rem;
  }

  .bj-balance-amount {
    font-size: 1.75rem;
  }

  .bj-balance-label {
    font-size: 0.688rem;
  }

  .bj-stats-toggle {
    font-size: 0.813rem;
    padding: 0.375rem 0.625rem;
  }

  .bj-playing-area {
    padding: 1rem 0.75rem;
  }

  .bj-cards {
    gap: 0.375rem;
    min-height: 70px;
  }

  .card {
    width: 50px;
    height: 70px;
  }

  .card-value {
    font-size: 0.75rem;
    top: 0.25rem;
    left: 0.25rem;
  }

  .card-suit {
    font-size: 1.5rem;
  }

  .bj-status {
    font-size: 1rem;
    min-height: 1.5rem;
  }

  .bj-action-area {
    padding: 1rem;
  }

  .bj-bet-chips {
    gap: 0.375rem;
  }

  .bj-chip {
    padding: 0.75rem 0.375rem;
    font-size: 0.875rem;
  }

  .bj-action-btn {
    padding: 1rem 1.25rem;
    font-size: 0.938rem;
    min-height: 50px;
  }
}

@media (max-width: 400px) {
  .bj-balance-amount {
    font-size: 1.5rem;
  }

  .bj-card {
    width: 45px;
    height: 63px;
  }

  .bj-chip {
    font-size: 0.813rem;
  }
}

/* Landscape */
@media (max-height: 600px) and (orientation: landscape) {
  .bj-topbar {
    padding: 0.5rem 1rem;
  }

  .bj-balance-amount {
    font-size: 1.5rem;
  }

  .bj-playing-area {
    padding: 0.75rem;
  }

  .bj-cards {
    min-height: 60px;
  }

  .card {
    width: 45px;
    height: 63px;
  }

  .bj-action-area {
    padding: 0.75rem 1rem 0.5rem;
  }

  .bj-action-btn {
    padding: 0.75rem 1rem;
    min-height: 44px;
    font-size: 0.875rem;
  }

  .bj-bet-display {
    padding: 0.75rem;
  }

  .bj-chip {
    padding: 0.625rem 0.375rem;
    font-size: 0.813rem;
  }
}

/* ===== Interesting Page ===== */
.interesting-section {
  padding: 3rem 0;
}

.interesting-item {
  margin-bottom: 4rem;
}

.interesting-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.interesting-header h2 {
  margin: 0;
}

.interesting-controls {
  display: flex;
  gap: 0.5rem;
}

.interesting-description {
  background: #fafafa;
  border-left: 3px solid #000;
  padding: 1.5rem;
  margin-bottom: 2rem;
  border-radius: 0 4px 4px 0;
}

.interesting-description p {
  margin-bottom: 0.75rem;
}

.interesting-description p:last-child {
  margin-bottom: 0;
}

.simulation-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  margin-bottom: 2rem;
}

.stat-box {
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 1rem;
  text-align: center;
}

.stat-label {
  font-size: 0.813rem;
  color: #666;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 0.5rem;
}

.stat-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: #000;
}

.chart-container {
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 2rem 1rem;
  margin-bottom: 2rem;
}

/* Mobile */
@media (max-width: 768px) {
  .interesting-section {
    padding: 2rem 0;
  }

  .interesting-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .interesting-controls {
    width: 100%;
  }

  .interesting-controls button {
    flex: 1;
  }

  .interesting-description {
    padding: 1rem;
  }

  .simulation-stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
  }

  .stat-value {
    font-size: 1.5rem;
  }

  .chart-container {
    padding: 1rem 0.5rem;
  }
}

.interesting-source {
  font-size: 0.875rem;
  color: #999;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid #e5e5e5;
}

.interesting-source a {
  color: #666;
  font-weight: 500;
}

.interesting-source a:hover {
  color: #000;
}

/* Monkey Theorem */
.monkey-container {
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 2rem;
  margin-bottom: 2rem;
}

.monkey-display {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
  padding: 2rem;
  background: #fafafa;
  border-radius: 4px;
}

.monkey-emoji {
  font-size: 3rem;
  animation: typing 0.5s ease-in-out infinite alternate;
}

@keyframes typing {
  from { transform: translateY(0); }
  to { transform: translateY(-5px); }
}

.monkey-output {
  flex: 1;
  font-family: 'Courier New', monospace;
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 2px;
  line-height: 1.6;
}

.monkey-output .match {
  color: #16a34a;
}

.monkey-output .no-match {
  color: #dc2626;
}

.monkey-output .success {
  color: #16a34a;
  animation: celebrate 0.5s ease-in-out;
}

@keyframes celebrate {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.1); }
}

.monkey-target {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.5rem;
  padding: 1rem;
  background: #f5f5f5;
  border-radius: 4px;
}

.target-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: #666;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.target-text {
  font-family: 'Courier New', monospace;
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 2px;
  color: #000;
}

.monkey-progress {
  margin-top: 1.5rem;
}

.progress-bar {
  width: 100%;
  height: 24px;
  background: #e5e5e5;
  border-radius: 12px;
  overflow: hidden;
  margin-bottom: 0.5rem;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #16a34a 0%, #22c55e 100%);
  transition: width 0.3s ease;
  width: 0%;
}

.progress-text {
  text-align: center;
  font-size: 0.875rem;
  font-weight: 600;
  color: #666;
}

/* Mobile */
@media (max-width: 768px) {
  .monkey-container {
    padding: 1rem;
  }

  .monkey-display {
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem 1rem;
  }

  .monkey-emoji {
    font-size: 2.5rem;
  }

  .monkey-output {
    font-size: 1.125rem;
    letter-spacing: 1px;
    text-align: center;
  }

  .monkey-target {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .target-text {
    font-size: 1rem;
    letter-spacing: 1px;
  }
}

/* Table of Contents */
.interesting-toc {
  background: #fafafa;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 1.5rem;
  margin-bottom: 3rem;
}

.toc-title {
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: #666;
  margin-bottom: 1rem;
}

.toc-links {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.toc-links a {
  font-size: 1rem;
  font-weight: 500;
  color: #000;
  padding: 0.5rem 0.75rem;
  border-left: 3px solid transparent;
  transition: all 0.2s;
}

.toc-links a:hover {
  border-left-color: #000;
  background: rgba(0, 0, 0, 0.03);
  padding-left: 1rem;
}

@media (max-width: 768px) {
  .interesting-toc {
    padding: 1rem;
    margin-bottom: 2rem;
  }

  .toc-links {
    gap: 0.5rem;
  }

  .toc-links a {
    font-size: 0.938rem;
  }
}

/* Section Divider */
.section-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, #e5e5e5 20%, #e5e5e5 80%, transparent 100%);
  margin: 4rem 0;
  position: relative;
}

.section-divider::before {
  content: '• • •';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: #fff;
  padding: 0 1rem;
  color: #999;
  letter-spacing: 0.5rem;
  font-size: 0.75rem;
}

@media (max-width: 768px) {
  .section-divider {
    margin: 3rem 0;
  }
}

/* Flight Map */
.flight-map-container {
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 1rem;
  margin-bottom: 2rem;
}

#flight-map {
  width: 100%;
  height: 400px;
  border-radius: 4px;
  overflow: hidden;
}

.plane-marker {
  font-size: 16px;
  text-align: center;
  line-height: 20px;
  color: #000;
  text-shadow: 0 0 3px #fff;
  cursor: pointer;
  transition: transform 0.2s;
}

.plane-marker:hover {
  transform: scale(1.3);
}

/* Leaflet popup customization */
.leaflet-popup-content-wrapper {
  border-radius: 4px;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
}

.leaflet-popup-content {
  margin: 0.75rem;
  font-size: 0.875rem;
  line-height: 1.6;
}

/* Mobile */
@media (max-width: 768px) {
  #flight-map {
    height: 300px;
  }

  .flight-map-container {
    padding: 0.5rem;
  }

  .plane-marker {
    font-size: 14px;
  }
}

/* Password Form */
.password-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2rem;
}

.password-form input[type="password"] {
  padding: 1rem;
  border: 1px solid #000;
  border-radius: 4px;
  font-size: 1rem;
  font-family: inherit;
}

.password-error {
  color: #dc2626;
  font-weight: 500;
  margin-top: 1rem;
}

/* Checklist */
.checklist-container {
  max-width: 800px;
}

.checklist-header {
  margin-bottom: 3rem;
}

.checklist-header h1 {
  margin-bottom: 1.5rem;
}

.checklist-progress {
  background: #fafafa;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 1.5rem;
}

.progress-stats {
  display: flex;
  justify-content: space-between;
  margin-bottom: 1rem;
  font-size: 0.938rem;
  font-weight: 600;
  color: #666;
}

.progress-stats #progress-percent {
  color: #000;
  font-size: 1.25rem;
}

.progress-bar-container {
  width: 100%;
  height: 20px;
  background: #e5e5e5;
  border-radius: 10px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, #16a34a 0%, #22c55e 100%);
  transition: width 0.3s ease;
  width: 0%;
}

.checklist-section {
  background: #fff;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 2rem;
  margin-bottom: 2rem;
}

.checklist-section h2 {
  margin: 0 0 1.5rem 0;
  font-size: 1.5rem;
}

.checklist-section h3 {
  margin: 1.5rem 0 1rem 0;
  font-size: 1.125rem;
}

.checklist-item {
  display: block;
  padding: 0.75rem 0;
  border-bottom: 1px solid #f5f5f5;
  cursor: pointer;
  transition: background 0.2s;
  font-size: 1rem;
  line-height: 1.6;
}

.checklist-item:last-of-type {
  border-bottom: none;
}

.checklist-item:hover {
  background: #fafafa;
}

.checklist-item input[type="checkbox"] {
  width: 18px;
  height: 18px;
  margin-right: 0.75rem;
  cursor: pointer;
  flex-shrink: 0;
}

.week-checkin {
  background: #f0fdf4;
  border-left: 3px solid #16a34a;
  padding: 1rem;
  margin: 1.5rem 0 0 0;
  font-size: 0.938rem;
  border-radius: 0 4px 4px 0;
}

.formula-section {
  background: #fef3c7;
  border: 1px solid #fbbf24;
  border-radius: 4px;
  padding: 2rem;
  margin-bottom: 2rem;
}

.formula-section h2 {
  margin: 0 0 1.5rem 0;
}

.links-section {
  background: #f5f5f5;
  border: 1px solid #e5e5e5;
  border-radius: 4px;
  padding: 2rem;
  margin-bottom: 2rem;
}

.links-section h2 {
  margin: 0 0 1rem 0;
}

.links-section ul {
  margin: 0;
  padding-left: 1.5rem;
}

.links-section li {
  margin-bottom: 0.5rem;
}

/* Mobile */
@media (max-width: 768px) {
  .checklist-section {
    padding: 1.5rem 1rem;
  }

  .checklist-header h1 {
    font-size: 1.75rem;
  }

  .checklist-progress {
    padding: 1rem;
  }

  .progress-stats {
    font-size: 0.875rem;
  }

  .progress-stats #progress-percent {
    font-size: 1.125rem;
  }

  .checklist-item {
    font-size: 0.938rem;
    padding: 0.625rem 0;
  }

  .week-checkin {
    padding: 0.75rem;
    font-size: 0.875rem;
  }
}