/* ==========================================================================
   DESIGN SYSTEM & VARIABLES
   ========================================================================== */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600&family=Lora:ital,wght@0,400;0,500;0,600;1,400&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --font-serif: 'Lora', Georgia, serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Color Palette */
  --bg-color: #fdfdfc;
  --bg-card: #ffffff;
  --text-main: #1c1f24;
  --text-muted: #5e6b7e;
  --primary-color: #1a365d; /* Classic Navy */
  --accent-color: #2b6cb0;  /* Slate Blue */
  --secondary-color: #276749; /* Forest Green for Language/Interests */
  --border-color: #e6ebf1;
  --code-bg: #f7fafc;
  
  /* Layout constraints */
  --max-width: 820px;
  --transition-speed: 0.2s;
}

/* Dark mode elements (optional, can be expanded) */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #0f141c;
    --bg-card: #171e29;
    --text-main: #e2e8f0;
    --text-muted: #94a3b8;
    --primary-color: #90cdf4;
    --accent-color: #63b3ed;
    --secondary-color: #48bb78;
    --border-color: #2d3748;
    --code-bg: #1a202c;
  }
}

/* ==========================================================================
   BASE STYLES
   ========================================================================== */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  line-height: 1.7;
  color: var(--text-main);
  background-color: var(--bg-color);
  -webkit-font-smoothing: antialiased;
  padding: 0 1.5rem;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  color: var(--primary-color);
  font-weight: 600;
  line-height: 1.25;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

h1 { font-size: 2.25rem; margin-top: 2rem; }
h2 { font-size: 1.5rem; margin-top: 2rem; border-bottom: 1px solid var(--border-color); padding-bottom: 0.5rem; }
h3 { font-size: 1.25rem; margin-top: 1.5rem; }

a {
  color: var(--accent-color);
  text-decoration: none;
  transition: color var(--transition-speed) ease;
}

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

p {
  margin-bottom: 1.5rem;
}

ul, ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.5rem;
}

blockquote {
  border-left: 4px solid var(--accent-color);
  padding: 0.5rem 0 0.5rem 1.25rem;
  margin: 1.5rem 0;
  color: var(--text-muted);
  font-style: italic;
  background-color: var(--code-bg);
  border-radius: 0 4px 4px 0;
}

/* ==========================================================================
   LAYOUT & CONTAINER
   ========================================================================== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ==========================================================================
   NAVIGATION
   ========================================================================== */
header {
  padding: 2.5rem 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
}

.logo-container {
  display: flex;
  flex-direction: column;
}

.logo {
  font-family: var(--font-sans);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-main);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.logo:hover {
  text-decoration: none;
  color: var(--accent-color);
}

.subtitle {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

nav {
  display: flex;
  gap: 1.5rem;
}

nav a {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
}

nav a:hover, nav a.active {
  color: var(--primary-color);
  text-decoration: none;
  border-bottom: 2px solid var(--primary-color);
  padding-bottom: 2px;
}

main {
  flex: 1;
  padding: 3rem 0;
}

footer {
  padding: 2.5rem 0;
  border-top: 1px solid var(--border-color);
  text-align: center;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ==========================================================================
   HOME PAGE (ABOUT / PROFILE)
   ========================================================================== */
.profile-section {
  display: flex;
  flex-direction: row;
  gap: 3rem;
  margin-bottom: 3rem;
  align-items: flex-start;
}

@media (max-width: 640px) {
  .profile-section {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 1.5rem;
  }
}

.profile-image-container {
  flex-shrink: 0;
}

.profile-image {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid var(--bg-card);
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
}

.bio-content {
  flex-grow: 1;
}

.bio-content h1 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

.bio-title {
  font-family: var(--font-sans);
  font-size: 1.1rem;
  color: var(--accent-color);
  margin-bottom: 1.25rem;
  font-weight: 500;
}

.social-links {
  display: flex;
  gap: 1.25rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

@media (max-width: 640px) {
  .social-links {
    justify-content: center;
  }
}

.social-link {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border-color);
  border-radius: 20px;
  background-color: var(--bg-card);
  transition: all var(--transition-speed) ease;
}

.social-link:hover {
  color: var(--primary-color);
  border-color: var(--accent-color);
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
}

/* ==========================================================================
   LANGUAGE LEARNING SECTION (PERSONAL INTERESTS)
   ========================================================================== */
.interests-container {
  margin-top: 3rem;
  padding: 2rem;
  background-color: var(--bg-card);
  border-radius: 12px;
  border: 1px solid var(--border-color);
  box-shadow: 0 4px 20px -2px rgba(0,0,0,0.02);
}

.interests-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.5rem;
}

.interests-header h2 {
  margin-top: 0;
  border-bottom: none;
  padding-bottom: 0;
  color: var(--secondary-color);
}

.interests-icon {
  font-size: 1.5rem;
}

.languages-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.language-card {
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.25rem;
  background-color: var(--bg-color);
  transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
  position: relative;
}

.language-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 12px -2px rgba(0, 0, 0, 0.05);
  border-color: var(--secondary-color);
}

.lang-flag-title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.lang-flag {
  font-size: 1.25rem;
}

.lang-name {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1rem;
  color: var(--text-main);
}

.lang-level {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  font-family: var(--font-sans);
  font-size: 0.75rem;
  font-weight: 600;
  background-color: var(--code-bg);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  border: 1px solid var(--border-color);
}

.lang-progress-bar {
  height: 6px;
  background-color: var(--border-color);
  border-radius: 3px;
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.lang-progress {
  height: 100%;
  background-color: var(--secondary-color);
  border-radius: 3px;
}

.lang-notes {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ==========================================================================
   BLOG / POST LISTING
   ========================================================================== */
.post-list {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.post-item {
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
}

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

.post-meta {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.post-tag {
  background-color: var(--code-bg);
  padding: 0.1rem 0.4rem;
  border-radius: 4px;
  font-size: 0.8rem;
}

.post-title {
  font-size: 1.4rem;
  margin-bottom: 0.75rem;
  margin-top: 0;
  font-family: var(--font-serif);
  font-weight: 600;
}

.post-title a {
  color: var(--text-main);
}

.post-title a:hover {
  color: var(--accent-color);
  text-decoration: none;
}

.post-summary {
  font-size: 1rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.read-more {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 500;
}

/* ==========================================================================
   BLOG POST DETAIL
   ========================================================================== */
.post-header {
  margin-bottom: 2.5rem;
}

.post-header h1 {
  font-size: 2.25rem;
  margin-top: 0;
  margin-bottom: 1rem;
}

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

.post-body h2 {
  font-size: 1.5rem;
  margin-top: 2.5rem;
  margin-bottom: 1rem;
}

.post-body h3 {
  font-size: 1.25rem;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
}

.post-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin: 2rem 0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.post-body code {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  background-color: var(--code-bg);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  color: #c53030;
}

.post-body pre {
  background-color: var(--code-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 1.25rem;
  overflow-x: auto;
  margin: 1.5rem 0;
}

.post-body pre code {
  background-color: transparent;
  padding: 0;
  border-radius: 0;
  color: inherit;
  font-size: 0.9rem;
  display: block;
}

.post-footer {
  margin-top: 4rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
  font-family: var(--font-sans);
  font-size: 0.95rem;
}

/* ==========================================================================
   CV PAGE
   ========================================================================== */
/* ==========================================================================
   CV PAGE (HTML Layout)
   ========================================================================== */
.cv-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 2rem;
  border-bottom: 2px solid var(--primary-color);
  padding-bottom: 1rem;
}

@media (max-width: 640px) {
  .cv-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }
}

.btn {
  font-family: var(--font-sans);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: var(--primary-color);
  color: #ffffff !important;
  padding: 0.6rem 1.2rem;
  border-radius: 6px;
  font-weight: 500;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: background-color var(--transition-speed) ease;
}

.btn:hover {
  background-color: var(--accent-color);
  text-decoration: none;
}

.cv-html-container {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
  font-size: 1rem;
}

.cv-contact-info {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  color: var(--text-muted);
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
  background-color: var(--code-bg);
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.cv-contact-item {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.cv-section-title {
  font-family: var(--font-sans);
  font-size: 1.25rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--primary-color);
  border-bottom: 2px solid var(--border-color);
  padding-bottom: 0.3rem;
  margin-bottom: 1.25rem;
  font-weight: 600;
}

.cv-item {
  margin-bottom: 1.5rem;
}

.cv-item:last-child {
  margin-bottom: 0;
}

.cv-item-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 0.35rem;
}

@media (max-width: 640px) {
  .cv-item-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.1rem;
  }
}

.cv-item-title {
  font-family: var(--font-sans);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
}

.cv-item-org {
  font-style: italic;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.cv-item-date {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.cv-bullets {
  padding-left: 1.25rem;
  margin-bottom: 0;
  font-size: 0.95rem;
}

.cv-bullets li {
  margin-bottom: 0.35rem;
}

.cv-grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

@media (max-width: 768px) {
  .cv-grid-2 {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

.skills-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.skills-category {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.skills-cat-name {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary-color);
}

.skills-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.skill-tag {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  background-color: var(--code-bg);
  border: 1px solid var(--border-color);
  padding: 0.25rem 0.6rem;
  border-radius: 4px;
  color: var(--text-main);
}

.pub-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  font-size: 0.95rem;
}

.pub-item {
  line-height: 1.6;
}

.pub-title {
  font-weight: 500;
}

.pub-authors {
  color: var(--text-main);
}

.pub-journal {
  font-style: italic;
  color: var(--text-muted);
}

.pub-year {
  font-weight: 500;
}

.award-item {
  display: flex;
  justify-content: space-between;
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
}

.award-name {
  font-weight: 500;
}

.award-date {
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-muted);
}

/* ==========================================================================
   CODE HIGHLIGHTING (Subtle custom themes)
   ========================================================================== */
.token-comment { color: #a0aec0; font-style: italic; }
.token-keyword { color: #805ad5; font-weight: 600; }
.token-string { color: #38a169; }
.token-number { color: #dd6b20; }
.token-function { color: #3182ce; }
.token-builtin { color: #319795; }