/* Modern CSS Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
}

* {
  margin: 0;
  padding: 0;
}

html,
body {
  height: 100%;
}

body {
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
}

input,
button,
textarea,
select {
  font: inherit;
}

p,
h1,
h2,
h3,
h4,
h5,
h6 {
  overflow-wrap: break-word;
}

ul,
ol {
  list-style: none;
}

a {
  text-decoration: none;
  color: inherit;
}

/* Apple-inspired Design System */
:root {
  --apple-blue: #007aff;
  --apple-gray: #8e8e93;
  --apple-light-gray: #f2f2f7;
  --apple-dark: #1c1c1e;
  --apple-white: #ffffff;
  --apple-purple: #af52de;
  --apple-pink: #ff2d55;
  --apple-orange: #ff9500;
  --apple-green: #34c759;

  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 40px;
  --spacing-xl: 64px;

  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 30px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.12);

  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  color: var(--apple-dark);
  background: var(--apple-light-gray);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.background-gradient {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
  background: linear-gradient(
    135deg,
    rgba(0, 122, 255, 0.03) 0%,
    rgba(175, 82, 222, 0.03) 50%,
    rgba(255, 45, 85, 0.03) 100%
  );
  animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {
  0%,
  100% {
    opacity: 1;
    transform: scale(1) rotate(0deg);
  }
  50% {
    opacity: 0.8;
    transform: scale(1.1) rotate(5deg);
  }
}

.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  padding: var(--spacing-sm) 0;
  animation: slideDown 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@keyframes slideDown {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-logo a {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  text-decoration: none;
  color: var(--apple-dark);
  font-weight: 600;
  font-size: 1.25rem;
  transition: var(--transition-fast);
}

.logo-icon {
  font-size: 1.5rem;
  animation: sparkle 2s ease-in-out infinite;
}

@keyframes sparkle {
  0%,
  100% {
    transform: scale(1) rotate(0deg);
    filter: brightness(1);
  }
  50% {
    transform: scale(1.2) rotate(10deg);
    filter: brightness(1.3);
  }
}

.nav-logo a:hover {
  transform: translateY(-2px);
}

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

.nav-link {
  text-decoration: none;
  color: var(--apple-gray);
  font-weight: 500;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--apple-blue);
  transition: var(--transition-smooth);
  transform: translateX(-50%);
}

.nav-link:hover {
  color: var(--apple-blue);
  background: rgba(0, 122, 255, 0.05);
}

.nav-link:hover::before {
  width: 80%;
}

.main-content {
  min-height: calc(100vh - 200px);
  padding: var(--spacing-xl) 0;
  animation: fadeInUp 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.content-wrapper {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.article-page {
  background: var(--apple-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
  animation: scaleIn 0.5s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.95);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.article-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-lg);
  border-bottom: 2px solid var(--apple-light-gray);
}

.article-header-animation {
  margin-bottom: var(--spacing-md);
}

.article-title {
  font-size: 3rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-sm);
  background: linear-gradient(135deg, var(--apple-blue), var(--apple-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: titleGlow 3s ease-in-out infinite;
}

@keyframes titleGlow {
  0%,
  100% {
    filter: brightness(1);
  }
  50% {
    filter: brightness(1.2);
  }
}

.article-meta {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-md);
  flex-wrap: wrap;
  margin-bottom: var(--spacing-sm);
}

.article-date {
  color: var(--apple-gray);
  font-size: 0.95rem;
}

.article-tags {
  display: flex;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
}

.tag {
  background: linear-gradient(135deg, var(--apple-blue), var(--apple-purple));
  color: white;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 500;
  transition: var(--transition-fast);
  animation: tagFloat 3s ease-in-out infinite;
}

@keyframes tagFloat {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-3px);
  }
}

.tag:hover {
  transform: scale(1.05) translateY(-2px);
  box-shadow: var(--shadow-md);
}

.article-description {
  font-size: 1.25rem;
  color: var(--apple-gray);
  line-height: 1.6;
}

.article-content {
  font-size: 1.125rem;
  line-height: 1.8;
  color: #333;
}

.article-content h1,
.article-content h2 {
  font-size: 2rem;
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  color: var(--apple-dark);
}

.article-content h3 {
  font-size: 1.5rem;
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
}

.article-content p {
  margin-bottom: var(--spacing-md);
}

.article-content a {
  color: var(--apple-blue);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: var(--transition-fast);
}

.article-content a:hover {
  border-bottom-color: var(--apple-blue);
}

.article-content code {
  background: var(--apple-light-gray);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'SF Mono', Consolas, monospace;
  font-size: 0.9em;
}

.article-content pre {
  background: var(--apple-dark);
  color: #f8f8f2;
  padding: var(--spacing-md);
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin: var(--spacing-md) 0;
}

.article-content pre code {
  background: none;
  padding: 0;
  color: inherit;
}

.article-content blockquote {
  border-left: 4px solid var(--apple-blue);
  padding-left: var(--spacing-md);
  margin: var(--spacing-md) 0;
  color: var(--apple-gray);
  font-style: italic;
}

.article-content ul,
.article-content ol {
  margin-left: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
}

.article-content li {
  margin-bottom: var(--spacing-xs);
}

.article-content img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-md);
  margin: var(--spacing-md) 0;
  box-shadow: var(--shadow-md);
}

.article-footer {
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-lg);
  border-top: 2px solid var(--apple-light-gray);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--apple-blue);
  text-decoration: none;
  font-weight: 500;
  transition: var(--transition-fast);
}

.back-arrow {
  transition: var(--transition-fast);
}

.back-link:hover {
  gap: var(--spacing-sm);
}

.back-link:hover .back-arrow {
  transform: translateX(-4px);
}

.page-content {
  background: var(--apple-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
}

.page-title {
  font-size: 3rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  background: linear-gradient(135deg, var(--apple-blue), var(--apple-purple));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.page-description {
  font-size: 1.25rem;
  color: var(--apple-gray);
  margin-bottom: var(--spacing-lg);
}

.page-body {
  font-size: 1.125rem;
  line-height: 1.8;
}

.page-body h1,
.page-body h2 {
  font-size: 2rem;
  margin-top: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  color: var(--apple-dark);
}

.page-body h3 {
  font-size: 1.5rem;
  margin-top: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
}

.page-body p {
  margin-bottom: var(--spacing-md);
}

.page-body ul,
.page-body ol {
  margin-left: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
}

.page-body li {
  margin-bottom: var(--spacing-xs);
}

.page-body a {
  color: var(--apple-blue);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: var(--transition-fast);
}

.page-body a:hover {
  border-bottom-color: var(--apple-blue);
}

.footer {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  padding: var(--spacing-lg) 0;
  margin-top: var(--spacing-xl);
}

.footer-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  text-align: center;
}

.footer-animation {
  display: flex;
  justify-content: center;
  margin-bottom: var(--spacing-sm);
}

.footer-text {
  font-size: 1rem;
  color: var(--apple-gray);
  margin-bottom: var(--spacing-xs);
}

.heart {
  color: var(--apple-pink);
  animation: heartbeat 1.5s ease-in-out infinite;
  display: inline-block;
}

@keyframes heartbeat {
  0%,
  100% {
    transform: scale(1);
  }
  10%,
  30% {
    transform: scale(1.2);
  }
  20%,
  40% {
    transform: scale(1);
  }
}

.footer-copyright {
  font-size: 0.875rem;
  color: var(--apple-gray);
}

@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: var(--spacing-sm);
  }

  .nav-menu {
    gap: var(--spacing-sm);
  }

  .article-title,
  .page-title {
    font-size: 2rem;
  }

  .article-page,
  .page-content {
    padding: var(--spacing-md);
  }

  .content-wrapper {
    padding: 0 var(--spacing-sm);
  }
}

html {
  scroll-behavior: smooth;
}

::selection {
  background: rgba(0, 122, 255, 0.2);
  color: var(--apple-dark);
}

img {
  animation: imageLoad 0.5s ease-in-out;
}

@keyframes imageLoad {
  from {
    opacity: 0;
    transform: scale(0.98);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}