/* ==========================================================================
   Apple-Inspired Personal Website
   Design System & Styles
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Variables / Design Tokens
   -------------------------------------------------------------------------- */
:root {
  /* Core Colors */
  --color-bg: #ffffff;
  --color-bg-secondary: #f5f5f7;
  --color-text: #1d1d1f;
  --color-text-secondary: #86868b;
  --color-accent: #0071e3;
  --color-accent-hover: #0077ed;
  --color-border: #d2d2d7;
  --color-nav-bg: rgba(255, 255, 255, 0.8);
  
  /* Typography Scale */
  --font-display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Segoe UI", Roboto, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", sans-serif;
  
  --text-hero: 56px;
  --text-h1: 48px;
  --text-h2: 32px;
  --text-h3: 21px;
  --text-body: 17px;
  --text-small: 14px;
  --text-micro: 12px;
  
  /* Spacing */
  --space-xs: 8px;
  --space-sm: 12px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 48px;
  --space-xxl: 80px;
  
  /* Transitions */
  --ease-out: cubic-bezier(0.25, 0.1, 0.25, 1);
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
  --duration-fast: 0.2s;
  --duration-normal: 0.3s;
  --duration-slow: 0.5s;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--text-body);
  line-height: 1.47059;
  color: var(--color-text);
  background: var(--color-bg);
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--duration-fast) var(--ease-out);
}

ul, ol {
  list-style: none;
}

img {
  max-width: 100%;
  display: block;
}

/* --------------------------------------------------------------------------
   Typography
   -------------------------------------------------------------------------- */
h1, h2, h3, h4 {
  font-weight: 600;
  letter-spacing: -0.018em;
  line-height: 1.1;
}

h1 { font-size: var(--text-h1); }
h2 { font-size: var(--text-h2); letter-spacing: -0.015em; }
h3 { font-size: var(--text-h3); letter-spacing: -0.011em; }

p {
  line-height: 1.6;
}

.eyebrow {
  font-size: var(--text-small);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--color-text-secondary);
}

.accent-text {
  color: var(--color-accent);
}

/* --------------------------------------------------------------------------
   Navigation Header
   -------------------------------------------------------------------------- */
.nav-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--color-nav-bg);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.nav-container {
  max-width: 1024px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 21px;
  font-weight: 600;
  letter-spacing: -0.011em;
  color: var(--color-text);
  transition: opacity var(--duration-fast) var(--ease-out);
}

.nav-logo:hover {
  opacity: 0.7;
}

.nav-links {
  display: flex;
  gap: var(--space-xl);
}

.nav-links a {
  font-size: var(--text-small);
  color: var(--color-text);
  opacity: 0.8;
  position: relative;
  padding: 4px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-text);
  transition: width var(--duration-normal) var(--ease-smooth);
}

.nav-links a:hover {
  opacity: 1;
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-links a.active::after {
  width: 100%;
}

/* Mobile Navigation */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
  background: none;
  border: none;
}

.nav-toggle span {
  width: 20px;
  height: 2px;
  background: var(--color-text);
  transition: var(--duration-normal) var(--ease-out);
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--space-xxl) var(--space-lg);
  background: linear-gradient(180deg, #f5f5f7 0%, var(--color-bg) 100%);
}

.hero-content {
  max-width: 800px;
}

.hero-eyebrow {
  font-size: var(--text-small);
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-md);
  animation: fadeInUp 0.8s var(--ease-out);
}

.hero h1 {
  font-size: clamp(40px, 8vw, 72px);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.05;
  margin-bottom: var(--space-lg);
  animation: fadeInUp 0.8s var(--ease-out) 0.1s both;
}

.hero-subtitle {
  font-size: clamp(19px, 2.5vw, 28px);
  line-height: 1.35;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-xl);
  animation: fadeInUp 0.8s var(--ease-out) 0.2s both;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: var(--text-body);
  color: var(--color-accent);
  font-weight: 400;
  transition: gap var(--duration-normal) var(--ease-out);
}

.hero-cta:hover {
  gap: 14px;
}

.hero-cta svg {
  width: 20px;
  height: 20px;
}

/* --------------------------------------------------------------------------
   Featured Cards Grid
   -------------------------------------------------------------------------- */
.featured-section {
  padding: var(--space-xxl) var(--space-lg);
  max-width: 1200px;
  margin: 0 auto;
}

.featured-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--space-lg);
}

.featured-card {
  background: var(--color-bg);
  border-radius: 18px;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
  transition: transform var(--duration-normal) var(--ease-smooth),
              box-shadow var(--duration-normal) var(--ease-smooth);
  cursor: pointer;
}

.featured-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
}

.featured-card-image {
  aspect-ratio: 16 / 10;
  background: var(--color-bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.featured-card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--duration-slow) var(--ease-smooth);
}

.featured-card:hover .featured-card-image img {
  transform: scale(1.03);
}

.featured-card-body {
  padding: var(--space-lg);
}

.featured-card-category {
  font-size: var(--text-small);
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: var(--space-xs);
}

.featured-card h3 {
  margin-bottom: var(--space-sm);
  color: var(--color-text);
}

.featured-card p {
  color: var(--color-text-secondary);
  font-size: var(--text-small);
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Page Header (Inner Pages)
   -------------------------------------------------------------------------- */
.page-header {
  padding-top: calc(52px + var(--space-xxl));
  padding-bottom: var(--space-xl);
  padding-left: var(--space-lg);
  padding-right: var(--space-lg);
  text-align: center;
  background: linear-gradient(180deg, #f5f5f7 0%, var(--color-bg) 100%);
}

.page-header h1 {
  margin-bottom: var(--space-sm);
}

.page-header p {
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* --------------------------------------------------------------------------
   Content Sections
   -------------------------------------------------------------------------- */
.section {
  padding: var(--space-xxl) var(--space-lg);
  max-width: 980px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.section-header h2 {
  margin-bottom: var(--space-sm);
}

.section-header p {
  color: var(--color-text-secondary);
}

/* About Section */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: var(--space-xxl);
  align-items: center;
}

.about-image {
  aspect-ratio: 1;
  border-radius: 18px;
  overflow: hidden;
  background: var(--color-bg-secondary);
}

.about-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.about-content h2 {
  margin-bottom: var(--space-lg);
}

.about-content p {
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
}

/* --------------------------------------------------------------------------
   Podcast List
   -------------------------------------------------------------------------- */
.podcast-grid {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.podcast-item {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: var(--space-lg);
  padding: var(--space-lg);
  background: var(--color-bg);
  border-radius: 12px;
  border: 1px solid var(--color-border);
  transition: border-color var(--duration-fast) var(--ease-out),
              box-shadow var(--duration-fast) var(--ease-out);
}

.podcast-item:hover {
  border-color: var(--color-accent);
  box-shadow: 0 4px 20px rgba(0, 113, 227, 0.1);
}

.podcast-number {
  font-size: var(--text-h2);
  font-weight: 600;
  color: var(--color-text-secondary);
  opacity: 0.4;
  line-height: 1;
}

.podcast-info h3 {
  margin-bottom: var(--space-xs);
}

.podcast-info p {
  color: var(--color-text-secondary);
  font-size: var(--text-small);
}

.podcast-links {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.podcast-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--color-bg-secondary);
  color: var(--color-text-secondary);
  transition: background var(--duration-fast) var(--ease-out),
              color var(--duration-fast) var(--ease-out);
}

.podcast-links a:hover {
  background: var(--color-accent);
  color: white;
}

/* --------------------------------------------------------------------------
   Recipe Gallery
   -------------------------------------------------------------------------- */
.recipe-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-lg);
}

.recipe-card {
  background: var(--color-bg);
  border-radius: 18px;
  overflow: hidden;
  border: 1px solid rgba(0, 0, 0, 0.05);
  transition: transform var(--duration-normal) var(--ease-smooth),
              box-shadow var(--duration-normal) var(--ease-smooth);
}

.recipe-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.1);
}

.recipe-card-image {
  aspect-ratio: 4 / 3;
  background: linear-gradient(135deg, #f5f5f7 0%, #e8e8ed 100%);
  display: flex;
  align-items: center;
  justify-content: center;
}

.recipe-card-image span {
  font-size: 48px;
}

.recipe-card-body {
  padding: var(--space-lg);
}

.recipe-card-meta {
  font-size: var(--text-micro);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-xs);
}

.recipe-card h3 {
  margin-bottom: var(--space-xs);
}

.recipe-card p {
  color: var(--color-text-secondary);
  font-size: var(--text-small);
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--space-xl) var(--space-lg);
  margin-top: var(--space-xxl);
}

.footer-container {
  max-width: 980px;
  margin: 0 auto;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: var(--space-xl);
  margin-bottom: var(--space-lg);
  flex-wrap: wrap;
}

.footer-nav a {
  font-size: var(--text-small);
  color: var(--color-text-secondary);
}

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

.footer-bottom {
  text-align: center;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
}

.footer-bottom p {
  font-size: var(--text-micro);
  color: var(--color-text-secondary);
}

/* --------------------------------------------------------------------------
   Animations
   -------------------------------------------------------------------------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* Staggered animations for lists */
.featured-card:nth-child(1) { animation: fadeInUp 0.6s var(--ease-out) 0.1s both; }
.featured-card:nth-child(2) { animation: fadeInUp 0.6s var(--ease-out) 0.2s both; }
.featured-card:nth-child(3) { animation: fadeInUp 0.6s var(--ease-out) 0.3s both; }

/* --------------------------------------------------------------------------
   Responsive Design
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {
  :root {
    --text-hero: 40px;
    --text-h1: 36px;
    --text-h2: 28px;
    --text-h3: 19px;
  }
  
  .nav-links {
    display: none;
    position: absolute;
    top: 52px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-bg);
    padding: var(--space-lg);
    gap: var(--space-md);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  }
  
  .nav-links.open {
    display: flex;
  }
  
  .nav-toggle {
    display: flex;
  }
  
  .hero {
    min-height: auto;
    padding: calc(var(--space-xxl) + 52px) var(--space-lg) var(--space-xxl);
  }
  
  .about-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }
  
  .about-image {
    max-width: 300px;
    margin: 0 auto;
  }
  
  .podcast-item {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
  
  .podcast-number {
    font-size: var(--text-h3);
  }
  
  .podcast-links {
    justify-content: flex-start;
  }
  
  .featured-grid {
    grid-template-columns: 1fr;
  }
  
  .recipe-grid {
    grid-template-columns: 1fr;
  }
  
  .footer-nav {
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
  }
}

@media (max-width: 480px) {
  :root {
    --text-hero: 32px;
    --text-h1: 28px;
    --text-h2: 24px;
  }
  
  .nav-container {
    padding: 0 var(--space-md);
  }
  
  .section {
    padding: var(--space-xl) var(--space-md);
  }
}