/* ── Design Tokens ── */
:root {
  --bg-dark:    #0a0c10;
  --bg-card:    #161b22;
  --bg-card2:   #1c2128;
  --text-main:  #c9d1d9;
  --text-muted: #8b949e;
  --accent-green:  #2ea043;
  --accent-blue:   #58a6ff;
  --accent-orange: #e3b341;
  --border:     #30363d;

  --font-mono: "Fira Code", monospace;
  --font-sans: "Inter", sans-serif;
  --ease: all 0.25s cubic-bezier(0.645, 0.045, 0.355, 1);
}

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

html { scroll-behavior: smooth; }

body {
  background-color: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
  overflow-x: hidden;
}

a { text-decoration: none; color: inherit; transition: var(--ease); }
ul { list-style: none; }

.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

/* ── Header ── */
.main-header {
  position: sticky;
  top: 0;
  z-index: 200;
  height: 70px;
  display: flex;
  align-items: center;
  padding: 0 24px;
  background-color: rgba(10, 12, 16, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 32px;
}

.logo {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-green);
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: color 0.2s;
}

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

.lang-toggle {
  flex-shrink: 0;
  background: none;
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 4px 14px;
  cursor: pointer;
  transition: var(--ease);
}

.lang-toggle .lang-text {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent-green);
}

.lang-toggle:hover {
  border-color: var(--accent-green);
  background-color: rgba(46, 160, 67, 0.08);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 18px;
  background: none;
  border: none;
  cursor: pointer;
  margin-left: auto;
  padding: 0;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--text-main);
  border-radius: 2px;
  transition: var(--ease);
}

.hamburger.open span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

/* ── Hero ── */
.hero-section {
  min-height: calc(100vh - 70px);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding: 60px 0;
}

.terminal-window {
  background-color: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: 0 20px 60px -15px rgba(0, 0, 0, 0.6);
  max-width: 820px;
  width: 100%;
  overflow: hidden;
}

.terminal-header {
  background-color: #0d1117;
  padding: 10px 16px;
  display: flex;
  align-items: center;
  gap: 6px;
  border-bottom: 1px solid var(--border);
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}
.dot.red    { background: #ff5f56; }
.dot.yellow { background: #ffbd2e; }
.dot.green  { background: #27c93f; }

.terminal-title {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin: 0 auto;
}

.terminal-body { padding: 40px 44px; }

.command {
  font-family: var(--font-mono);
  color: var(--accent-green);
  margin-bottom: 20px;
  font-size: 0.95rem;
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 700;
  line-height: 1.15;
  color: #fff;
  margin-bottom: 14px;
}

.highlight { color: var(--accent-blue); }

.hero-subtitle {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  line-height: 1.8;
}

.hero-desc {
  color: var(--text-muted);
  font-size: 0.97rem;
  line-height: 1.8;
  max-width: 600px;
  margin-bottom: 28px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 36px;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-green);
  background-color: rgba(46, 160, 67, 0.1);
  border: 1px solid rgba(46, 160, 67, 0.2);
  padding: 4px 12px;
  border-radius: 4px;
}

/* Cursor */
.cursor {
  display: inline-block;
  width: 2px;
  height: 1.2em;
  vertical-align: middle;
  background-color: var(--accent-green);
  animation: blink 1s step-end infinite;
}

@keyframes blink { 0%, 100% { opacity: 1; } 50% { opacity: 0; } }

/* Buttons */
.cta-group { display: flex; gap: 16px; flex-wrap: wrap; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: var(--ease);
  border: 1px solid transparent;
}

.btn-primary {
  border-color: var(--accent-green);
  color: var(--accent-green);
}
.btn-primary:hover { background-color: rgba(46, 160, 67, 0.1); }

.btn-outline {
  border-color: var(--text-muted);
  color: var(--text-main);
}
.btn-outline:hover {
  border-color: var(--text-main);
  background-color: rgba(255,255,255,0.05);
}

/* Grid bg */
.grid-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
}

/* ── Sections ── */
.section { padding: 80px 0; }

.section-title {
  font-size: 1.9rem;
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 48px;
}

.section-title::after {
  content: "";
  display: block;
  height: 1px;
  background-color: var(--border);
  flex: 1;
}

.prefix {
  font-family: var(--font-mono);
  color: var(--accent-green);
  font-weight: 400;
  font-size: 1.6rem;
}

/* ── About ── */
.about-text p {
  color: var(--text-muted);
  line-height: 1.85;
  margin-bottom: 18px;
  font-size: 0.97rem;
}

.about-text strong { color: var(--text-main); }

.about-text em { color: var(--accent-blue); font-style: normal; }


/* ── Skills ── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 18px;
}

.skill-category {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 22px 20px;
  transition: var(--ease);
}

.skill-category:hover {
  border-color: rgba(46, 160, 67, 0.4);
  transform: translateY(-3px);
}

.skill-cat-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
}

.skill-cat-header i {
  color: var(--accent-green);
  font-size: 1.1rem;
  width: 20px;
  text-align: center;
}

.skill-cat-header h3 {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-green);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.skill-items {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.skill-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  color: var(--text-muted);
  padding: 6px 0;
  border-bottom: 1px solid rgba(48,54,61,0.5);
}

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

.skill-item i {
  width: 16px;
  text-align: center;
  color: var(--accent-blue);
  font-size: 0.9rem;
}

.learning-badge {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--accent-orange);
  border: 1px solid rgba(227, 179, 65, 0.3);
  border-radius: 20px;
  padding: 1px 8px;
}

/* ── Projects ── */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid transparent;
  border-radius: 10px;
  padding: 28px;
  transition: var(--ease);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.project-card:hover {
  transform: translateY(-5px);
  border-color: rgba(46, 160, 67, 0.35);
  box-shadow: 0 8px 30px rgba(0,0,0,0.3);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.folder-icon {
  font-size: 2rem;
  color: var(--accent-green);
}

.card-links a {
  font-size: 1.15rem;
  color: var(--text-muted);
  margin-left: 12px;
}

.card-links a:hover { color: var(--accent-blue); }

.project-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.wip-badge {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--accent-orange);
  border: 1px solid rgba(227,179,65,0.4);
  border-radius: 20px;
  padding: 2px 10px;
}

.project-problem, .project-solution { display: flex; flex-direction: column; gap: 6px; }

.pslabel {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-radius: 4px;
  padding: 2px 8px;
  width: fit-content;
}

.problem-label {
  color: #f85149;
  background: rgba(248, 81, 73, 0.1);
  border: 1px solid rgba(248, 81, 73, 0.2);
}

.solution-label {
  color: var(--accent-green);
  background: rgba(46, 160, 67, 0.1);
  border: 1px solid rgba(46, 160, 67, 0.2);
}

.project-problem p, .project-solution p {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.65;
}

.project-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: auto;
  font-family: var(--font-mono);
  font-size: 0.72rem;
}

.project-tags li {
  color: var(--accent-green);
  background: rgba(46, 160, 67, 0.08);
  border: 1px solid rgba(46, 160, 67, 0.2);
  padding: 3px 12px;
  border-radius: 50px;
  transition: var(--ease);
}

.project-tags li:hover {
  background: rgba(46, 160, 67, 0.18);
  transform: translateY(-2px);
}

/* ── Reading ── */
.reading-intro {
  color: var(--text-muted);
  font-size: 0.97rem;
  margin-bottom: 32px;
  line-height: 1.7;
}

.books-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}

.book-card {
  display: flex;
  gap: 22px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 28px;
  transition: var(--ease);
}

.book-card:hover {
  border-color: rgba(88, 166, 255, 0.3);
  transform: translateY(-3px);
}

.book-icon {
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  border-radius: 10px;
  background: rgba(88, 166, 255, 0.1);
  border: 1px solid rgba(88, 166, 255, 0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
  color: var(--accent-blue);
}

.book-info { display: flex; flex-direction: column; gap: 6px; }

.book-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #fff;
}

.book-author {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
}

.book-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-top: 4px;
}

.book-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent-blue);
  background: rgba(88, 166, 255, 0.08);
  border: 1px solid rgba(88, 166, 255, 0.2);
  padding: 3px 12px;
  border-radius: 50px;
  width: fit-content;
  margin-top: 6px;
}

/* ── Footer ── */
footer {
  margin-top: 40px;
  padding: 60px 0 40px;
  border-top: 1px solid var(--border);
}

.footer-content { text-align: center; }

.footer-heading {
  font-size: 2rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 14px;
}

.footer-desc {
  color: var(--text-muted);
  font-size: 0.97rem;
  max-width: 440px;
  margin: 0 auto 32px;
  line-height: 1.7;
}

.social-links { display: flex; justify-content: center; gap: 20px; margin-bottom: 28px; }

.social-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border);
  font-size: 1.1rem;
  color: var(--text-muted);
  transition: var(--ease);
}

.social-link:hover {
  color: var(--accent-green);
  border-color: var(--accent-green);
  background: rgba(46,160,67,0.08);
  transform: translateY(-3px);
}

.server-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border: 1px solid var(--border);
  border-radius: 20px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.server-badge i { color: var(--accent-green); }

.copyright {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* ── Responsive ── */
@media (max-width: 900px) {
  .skills-grid { grid-template-columns: repeat(2, 1fr); }
  .projects-grid { grid-template-columns: 1fr; }
  .books-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .hero-title { font-size: 2.2rem; }
  .terminal-body { padding: 28px 24px; }

  .about-content { grid-template-columns: 1fr; gap: 36px; }

  .hamburger { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0;
    right: 0;
    background: rgba(10,12,16,0.97);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    align-items: center;
    gap: 0;
    padding: 12px 0;
  }

  .nav-links.open { display: flex; }

  .nav-links li { width: 100%; text-align: center; }
  .nav-links li a { display: block; padding: 14px 24px; font-size: 0.92rem; }

  .lang-toggle { margin-left: 0; }
}

@media (max-width: 480px) {
  .skills-grid { grid-template-columns: 1fr; }
  .hero-title { font-size: 1.9rem; }
  .book-card { flex-direction: column; }
}