/* ================================================================
   GITHUB PAGES — PERSONAL WEBSITE
   styles.css  |  Mobile-first responsive layout
================================================================ */

/* ----------------------------------------------------------------
   1. CUSTOM PROPERTIES (Design Tokens)
---------------------------------------------------------------- */
:root {
  /* Colors */
  --clr-bg:           #0d1117;
  --clr-bg-alt:       #161b22;
  --clr-border:       #21262d;
  --clr-text:         #e6edf3;
  --clr-text-muted:   #8b949e;
  --clr-accent:       #58a6ff;
  --clr-accent-hover: #79b8ff;
  --clr-accent-muted: #1f3a5f;
  --clr-green-muted:  #1a3a2a;
  --clr-purple-muted: #2d1b4e;

  /* Typography */
  --font-sans:   'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  2rem;
  --text-4xl:  2.5rem;
  --text-5xl:  3.5rem;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-24: 6rem;

  /* Layout */
  --max-w: 1100px;
  --radius: 0.75rem;
  --radius-sm: 0.375rem;

  /* Transitions */
  --transition: 200ms ease;
}

/* ----------------------------------------------------------------
   2. RESET & BASE
---------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover, a:focus-visible {
  color: var(--clr-accent-hover);
  text-decoration: underline;
}

ul {
  list-style: none;
}

/* Accessible focus ring */
:focus-visible {
  outline: 2px solid var(--clr-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* ----------------------------------------------------------------
   3. UTILITY CLASSES
---------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-w);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.section {
  padding-block: var(--space-24);
}

.section__title {
  font-size: var(--text-3xl);
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--space-3);
}

.section__subtitle {
  color: var(--clr-text-muted);
  text-align: center;
  margin-bottom: var(--space-12);
  font-size: var(--text-lg);
}

/* ----------------------------------------------------------------
   4. BUTTONS
---------------------------------------------------------------- */
.btn {
  display: inline-block;
  padding: 0.625rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: var(--text-base);
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
  border: 2px solid transparent;
  text-align: center;
  text-decoration: none;
}

.btn:hover, .btn:focus-visible {
  text-decoration: none;
}

.btn--primary {
  background: var(--clr-accent);
  color: #0d1117;
  border-color: var(--clr-accent);
}

.btn--primary:hover, .btn--primary:focus-visible {
  background: var(--clr-accent-hover);
  border-color: var(--clr-accent-hover);
  color: #0d1117;
}

.btn--outline {
  background: transparent;
  color: var(--clr-accent);
  border-color: var(--clr-accent);
}

.btn--outline:hover, .btn--outline:focus-visible {
  background: var(--clr-accent);
  color: #0d1117;
}

.btn--sm {
  padding: 0.375rem 1rem;
  font-size: var(--text-sm);
}

.btn--full {
  width: 100%;
}

/* ----------------------------------------------------------------
   5. HEADER & NAVIGATION
---------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 17, 23, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--clr-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4rem;
}

.nav__logo {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--clr-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.nav__logo:hover {
  color: var(--clr-accent);
}

.nav__links {
  display: flex;
  gap: var(--space-8);
  align-items: center;
}

.nav__links a {
  color: var(--clr-text-muted);
  font-size: var(--text-sm);
  font-weight: 500;
  transition: color var(--transition);
  text-decoration: none;
}

.nav__links a:hover, .nav__links a:focus-visible {
  color: var(--clr-text);
}

/* Hamburger button (hidden on desktop) */
.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.nav__toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--clr-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

/* ----------------------------------------------------------------
   6. HERO SECTION
---------------------------------------------------------------- */
.hero {
  position: relative;
  overflow: hidden;
  padding-block: var(--space-24);
  min-height: calc(100vh - 4rem);
  display: flex;
  align-items: center;
}

.hero__inner {
  position: relative;
  z-index: 1;
}

.hero__eyebrow {
  font-size: var(--text-lg);
  color: var(--clr-accent);
  font-weight: 500;
  margin-bottom: var(--space-2);
}

.hero__name {
  font-size: clamp(var(--text-4xl), 8vw, var(--text-5xl));
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: var(--space-4);
}

.hero__tagline {
  font-size: var(--text-2xl);
  color: var(--clr-text-muted);
  margin-bottom: var(--space-4);
}

.hero__sub {
  max-width: 550px;
  color: var(--clr-text-muted);
  font-size: var(--text-lg);
  margin-bottom: var(--space-8);
}

.hero__actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}

/* Decorative background blob */
.hero__blob {
  position: absolute;
  top: -30%;
  right: -20%;
  width: 650px;
  height: 650px;
  background: radial-gradient(circle, rgba(88, 166, 255, 0.12) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

/* ----------------------------------------------------------------
   7. ABOUT SECTION
---------------------------------------------------------------- */
.about {
  background: var(--clr-bg-alt);
}

.about__inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-16);
  align-items: center;
}

.about__text .section__title {
  text-align: left;
}

.about__text p {
  color: var(--clr-text-muted);
  margin-bottom: var(--space-4);
  font-size: var(--text-lg);
}

/* Avatar placeholder — replace with a real <img> */
.about__avatar-placeholder {
  width: 100%;
  aspect-ratio: 1;
  max-width: 340px;
  margin: auto;
  background: var(--clr-border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--clr-text-muted);
  font-size: var(--text-xl);
  text-align: center;
  border: 2px dashed var(--clr-text-muted);
}

/* ----------------------------------------------------------------
   8. SKILLS SECTION
---------------------------------------------------------------- */
.skills__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-6);
}

.skill-card {
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: var(--space-8);
  transition: border-color var(--transition), transform var(--transition);
}

.skill-card:hover {
  border-color: var(--clr-accent);
  transform: translateY(-4px);
}

.skill-card__icon {
  font-size: 2rem;
  margin-bottom: var(--space-4);
}

.skill-card__title {
  font-size: var(--text-xl);
  font-weight: 600;
  margin-bottom: var(--space-4);
}

.skill-card__list {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.skill-card__list li {
  color: var(--clr-text-muted);
  font-size: var(--text-sm);
  padding-left: var(--space-4);
  position: relative;
}

.skill-card__list li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--clr-accent);
}

/* ----------------------------------------------------------------
   9. PORTFOLIO SECTION
---------------------------------------------------------------- */
.portfolio {
  background: var(--clr-bg-alt);
}

.portfolio__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-6);
}

.project-card {
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: transform var(--transition), border-color var(--transition);
}

.project-card:hover {
  transform: translateY(-4px);
  border-color: var(--clr-accent);
}

.project-card__header {
  height: 120px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.project-card__emoji {
  font-size: 3rem;
}

.project-card__body {
  padding: var(--space-6);
  flex: 1;
}

.project-card__title {
  font-size: var(--text-xl);
  font-weight: 600;
  margin-bottom: var(--space-3);
}

.project-card__desc {
  color: var(--clr-text-muted);
  font-size: var(--text-sm);
  margin-bottom: var(--space-4);
}

.project-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.tag {
  background: var(--clr-border);
  color: var(--clr-text-muted);
  font-size: var(--text-xs);
  font-weight: 500;
  padding: 0.2rem 0.6rem;
  border-radius: 9999px;
}

.project-card__footer {
  padding: var(--space-4) var(--space-6) var(--space-6);
  display: flex;
  gap: var(--space-3);
}

/* ----------------------------------------------------------------
   10. CONTACT SECTION
---------------------------------------------------------------- */
.contact__inner {
  max-width: 600px;
  margin-inline: auto;
  text-align: center;
}

.contact__inner .section__title,
.contact__inner .section__subtitle {
  text-align: center;
}

.contact__form {
  text-align: left;
  margin-top: var(--space-8);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
}

.form-group label {
  font-weight: 600;
  font-size: var(--text-sm);
  color: var(--clr-text);
}

.form-group input,
.form-group textarea {
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  color: var(--clr-text);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  padding: 0.75rem 1rem;
  width: 100%;
  transition: border-color var(--transition);
  resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--clr-accent);
}

.form-error {
  color: #f85149;
  font-size: var(--text-xs);
  min-height: 1rem;
}

.contact__note {
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  color: var(--clr-text-muted);
  text-align: center;
}

.contact__social {
  display: flex;
  justify-content: center;
  gap: var(--space-8);
  margin-top: var(--space-12);
  font-weight: 600;
}

.contact__social a {
  color: var(--clr-text-muted);
  font-size: var(--text-sm);
  transition: color var(--transition);
  text-decoration: none;
}

.contact__social a:hover {
  color: var(--clr-accent);
}

/* ----------------------------------------------------------------
   11. FOOTER
---------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--clr-border);
  padding-block: var(--space-8);
  text-align: center;
  font-size: var(--text-sm);
  color: var(--clr-text-muted);
}

/* ----------------------------------------------------------------
   12. RESPONSIVE — TABLET (max 768px)
---------------------------------------------------------------- */
@media (max-width: 768px) {

  /* Navigation — hamburger menu */
  .nav__toggle {
    display: flex;
  }

  .nav__links {
    position: fixed;
    inset: 4rem 0 0;
    background: var(--clr-bg);
    flex-direction: column;
    justify-content: center;
    gap: var(--space-8);
    font-size: var(--text-xl);
    transform: translateX(100%);
    transition: transform 300ms ease;
    z-index: 99;
    border-top: 1px solid var(--clr-border);
  }

  .nav__links.is-open {
    transform: translateX(0);
  }

  /* Hamburger to X animation */
  .nav__toggle.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav__toggle.is-open span:nth-child(2) { opacity: 0; }
  .nav__toggle.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  /* Hero */
  .hero {
    min-height: auto;
    padding-block: var(--space-16);
  }

  .hero__blob {
    display: none;
  }

  /* About — stack vertically */
  .about__inner {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }

  .about__text .section__title {
    text-align: center;
  }

  .about__image {
    order: -1;
  }

  .about__avatar-placeholder {
    max-width: 200px;
  }
}

/* ----------------------------------------------------------------
   13. RESPONSIVE — MOBILE (max 480px)
---------------------------------------------------------------- */
@media (max-width: 480px) {

  :root {
    --space-24: 4rem;
  }

  .hero__actions {
    flex-direction: column;
  }

  .hero__actions .btn {
    width: 100%;
    text-align: center;
  }

  .skills__grid {
    grid-template-columns: 1fr;
  }

  .portfolio__grid {
    grid-template-columns: 1fr;
  }
}

/* ----------------------------------------------------------------
   14. ANIMATIONS
---------------------------------------------------------------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-in {
  animation: fadeInUp 0.5s ease forwards;
}

/* Stagger children with custom delay */
.animate-in:nth-child(1) { animation-delay: 0ms; }
.animate-in:nth-child(2) { animation-delay: 100ms; }
.animate-in:nth-child(3) { animation-delay: 200ms; }
.animate-in:nth-child(4) { animation-delay: 300ms; }

/* Respect reduced-motion preference */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ----------------------------------------------------------------
   15. ABOUT — real avatar + stat badges
---------------------------------------------------------------- */
.about__avatar {
  width: 100%;
  max-width: 300px;
  border-radius: var(--radius);
  border: 3px solid var(--clr-border);
  display: block;
  margin: auto;
  object-fit: cover;
  transition: border-color var(--transition);
}

.about__avatar:hover {
  border-color: var(--clr-accent);
}

.about__stats {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-top: var(--space-6);
}

.stat-badge {
  display: flex;
  flex-direction: column;
  align-items: center;
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  padding: var(--space-3) var(--space-6);
  min-width: 80px;
  transition: border-color var(--transition);
}

.stat-badge:hover {
  border-color: var(--clr-accent);
}

.stat-badge__num {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--clr-accent);
  line-height: 1.2;
}

.stat-badge__label {
  font-size: var(--text-xs);
  color: var(--clr-text-muted);
  text-align: center;
  margin-top: var(--space-1);
}

/* ----------------------------------------------------------------
   16. REPOSITORIES SECTION
---------------------------------------------------------------- */
.repos {
  background: var(--clr-bg);
}

/* Toolbar: search + filter buttons */
.repos__toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  align-items: center;
  margin-bottom: var(--space-8);
}

.repos__search-wrap {
  flex: 1;
  min-width: 200px;
}

.repos__search {
  width: 100%;
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-sm);
  color: var(--clr-text);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  padding: 0.6rem 1rem;
  transition: border-color var(--transition);
}

.repos__search:focus {
  outline: none;
  border-color: var(--clr-accent);
}

.repos__search::placeholder {
  color: var(--clr-text-muted);
}

/* Language filter buttons */
.repos__filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.filter-btn {
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: 9999px;
  color: var(--clr-text-muted);
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: var(--text-xs);
  font-weight: 500;
  padding: 0.3rem 0.8rem;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}

.filter-btn:hover,
.filter-btn:focus-visible {
  border-color: var(--clr-accent);
  color: var(--clr-text);
}

.filter-btn--active {
  background: var(--clr-accent);
  border-color: var(--clr-accent);
  color: #0d1117;
  font-weight: 600;
}

/* Repos grid */
.repos__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--space-4);
  margin-bottom: var(--space-8);
}

/* Individual repo card */
.repo-card {
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  display: flex;
  flex-direction: column;
  padding: var(--space-6);
  transition: border-color var(--transition), transform var(--transition);
  text-decoration: none;
  color: inherit;
}

.repo-card:hover {
  border-color: var(--clr-accent);
  transform: translateY(-3px);
  text-decoration: none;
  color: inherit;
}

.repo-card__name {
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--clr-accent);
  margin-bottom: var(--space-2);
  word-break: break-word;
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.repo-card__fork-badge {
  font-size: var(--text-xs);
  background: var(--clr-border);
  color: var(--clr-text-muted);
  border-radius: 9999px;
  padding: 0.1rem 0.45rem;
  font-weight: 400;
  flex-shrink: 0;
}

.repo-card__desc {
  flex: 1;
  font-size: var(--text-sm);
  color: var(--clr-text-muted);
  line-height: 1.5;
  margin-bottom: var(--space-4);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.repo-card__desc--empty {
  color: var(--clr-border);   /* very dim — clearly a placeholder */
  font-style: italic;
  font-size: var(--text-xs);
}

.repo-card__meta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-top: auto;
}

.repo-meta-item {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: var(--text-xs);
  color: var(--clr-text-muted);
}

.lang-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.repo-card__updated {
  font-size: var(--text-xs);
  color: var(--clr-text-muted);
  margin-top: var(--space-3);
}

/* Loading skeleton */
@keyframes shimmer {
  0%   { background-position: -600px 0; }
  100% { background-position: 600px 0; }
}

.repo-skeleton {
  height: 140px;
  border-radius: var(--radius);
  background: linear-gradient(
    90deg,
    var(--clr-bg-alt) 25%,
    var(--clr-border) 50%,
    var(--clr-bg-alt) 75%
  );
  background-size: 1200px 100%;
  animation: shimmer 1.5s infinite linear;
}

/* Empty / error states */
.repos__empty,
.repos__error {
  text-align: center;
  padding: var(--space-16);
  color: var(--clr-text-muted);
}

.repos__error a {
  color: var(--clr-accent);
}

.repos__footer {
  text-align: center;
  margin-top: var(--space-4);
}

/* ----------------------------------------------------------------
   17. CONTACT — social link cards (replacing the old form)
---------------------------------------------------------------- */
.contact__inner {
  max-width: 680px;
  margin-inline: auto;
  text-align: center;
}

.contact__social {
  display: flex;
  justify-content: center;
  gap: var(--space-4);
  flex-wrap: wrap;
  margin-top: var(--space-12);
}

.social-link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-3);
  background: var(--clr-bg-alt);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius);
  padding: var(--space-6) var(--space-8);
  min-width: 130px;
  color: var(--clr-text-muted);
  font-size: var(--text-sm);
  font-weight: 600;
  text-decoration: none;
  transition: border-color var(--transition), color var(--transition), transform var(--transition);
}

.social-link:hover,
.social-link:focus-visible {
  border-color: var(--clr-accent);
  color: var(--clr-accent);
  transform: translateY(-3px);
  text-decoration: none;
}

.social-link__icon {
  display: flex;
  align-items: center;
  font-size: 1.4rem;
}