/* ========================================
   Design Tokens
   ======================================== */
:root {
  --color-bg: #FAFAFA;
  --color-bg-alt: #F2F2F2;
  --color-surface: #FFFFFF;
  --color-text: #1A1A1A;
  --color-text-secondary: #6B6B6B;
  --color-text-tertiary: #9A9A9A;
  --color-accent: #0066FF;
  --color-accent-hover: #0052CC;
  --color-border: #E5E5E5;
  --color-border-hover: #D0D0D0;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --font-mono: 'SF Mono', SFMono-Regular, ui-monospace, Menlo, Consolas, monospace;

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-height) + 24px);
}

body {
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  font-weight: 400;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body.no-scroll {
  overflow: hidden;
}

/* ========================================
   Background Blobs
   ======================================== */
.bg-blobs {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.bg-blobs__blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.45;
  will-change: transform;
}

.bg-blobs__blob--1 {
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 102, 255, 0.3) 0%, transparent 70%);
  top: -10%;
  right: -8%;
  animation: blob-drift-1 20s ease-in-out infinite alternate;
}

.bg-blobs__blob--2 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.25) 0%, transparent 70%);
  top: 40%;
  left: -10%;
  animation: blob-drift-2 24s ease-in-out infinite alternate;
}

.bg-blobs__blob--3 {
  width: 450px;
  height: 450px;
  background: radial-gradient(circle, rgba(59, 200, 190, 0.2) 0%, transparent 70%);
  bottom: -5%;
  right: 15%;
  animation: blob-drift-3 22s ease-in-out infinite alternate;
}

@keyframes blob-drift-1 {
  0%   { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-60px, 40px) scale(1.1); }
}

@keyframes blob-drift-2 {
  0%   { transform: translate(0, 0) scale(1); }
  100% { transform: translate(50px, -30px) scale(1.05); }
}

@keyframes blob-drift-3 {
  0%   { transform: translate(0, 0) scale(1); }
  100% { transform: translate(-40px, -50px) scale(1.15); }
}

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

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

/* ========================================
   Utilities
   ======================================== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  padding: 8px 16px;
  background: var(--color-accent);
  color: #FFFFFF;
  border-radius: 6px;
  font-weight: 500;
  z-index: 1000;
}

.skip-link:focus {
  top: 16px;
}

.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 96px 0;
}

.section__header {
  margin-bottom: 48px;
}

.section__title {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  color: var(--color-text);
}

.section__title::after {
  content: '';
  display: block;
  width: 40px;
  height: 3px;
  background: var(--color-accent);
  margin-top: 12px;
  border-radius: 2px;
}

/* ========================================
   Navigation
   ======================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  background: rgba(250, 250, 250, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 100;
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s ease;
}

.nav--scrolled {
  border-bottom-color: var(--color-border);
}

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

.nav__logo {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: -0.02em;
}

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

.nav__menu {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}

.nav__link {
  font-size: 0.9375rem;
  font-weight: 400;
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

.nav__link:hover,
.nav__link--active {
  color: var(--color-text);
}

.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav__toggle-line {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: 1px;
  transition: transform 0.3s var(--ease-out), opacity 0.2s ease;
  transform-origin: center;
}

.nav__toggle[aria-expanded="true"] .nav__toggle-line:first-child {
  transform: translateY(3.5px) rotate(45deg);
}

.nav__toggle[aria-expanded="true"] .nav__toggle-line:last-child {
  transform: translateY(-3.5px) rotate(-45deg);
}

/* ========================================
   Hero
   ======================================== */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  padding-top: var(--nav-height);
}

.hero__greeting {
  font-size: 1.125rem;
  font-weight: 400;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.hero__name {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.1;
  color: var(--color-text);
  margin-bottom: 12px;
}

.hero__tagline {
  font-size: clamp(1.125rem, 2vw, 1.375rem);
  font-weight: 400;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.hero__bio {
  max-width: 560px;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
}

.hero__actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero__scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  animation: bounce 2s infinite;
}

.hero__scroll-hint svg {
  width: 24px;
  height: 24px;
  stroke: var(--color-text-tertiary);
}

@keyframes bounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  font-size: 0.9375rem;
  font-weight: 500;
  font-family: var(--font-sans);
  border-radius: 8px;
  text-decoration: none;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
}

.btn--primary {
  background: var(--color-accent);
  color: #FFFFFF;
}

.btn--primary:hover {
  background: var(--color-accent-hover);
  color: #FFFFFF;
}

.btn--secondary {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn--secondary:hover {
  border-color: var(--color-border-hover);
  background: var(--color-bg-alt);
}

/* ========================================
   About
   ======================================== */
.about__content {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.about__text p + p {
  margin-top: 16px;
}

.about__details {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.about__detail {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.about__label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.about__value {
  font-weight: 500;
  color: var(--color-text);
}

/* ========================================
   Experience
   ======================================== */
.experience__list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.experience__item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 24px 0;
  border-left: 1px solid var(--color-border);
  padding-left: 24px;
  position: relative;
}

.experience__item::before {
  content: '';
  position: absolute;
  left: -4px;
  top: 30px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--color-border);
  border: 2px solid var(--color-bg);
}

.experience__date {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--color-text-tertiary);
}

.experience__role {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.01em;
}

.experience__company {
  font-weight: 400;
  color: var(--color-text-secondary);
}

.experience__description {
  margin-top: 4px;
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
}

/* ========================================
   Projects
   ======================================== */
.projects__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 28px;
  transition: border-color 0.2s ease, box-shadow 0.3s ease, transform 0.3s var(--ease-out);
}

.project-card:hover {
  border-color: var(--color-border-hover);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
  transform: translateY(-2px);
}

.project-card__tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--color-accent);
  background: rgba(0, 102, 255, 0.08);
  padding: 4px 10px;
  border-radius: 100px;
  margin-bottom: 16px;
}

.project-card__title {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: -0.01em;
  margin-bottom: 8px;
}

.project-card__description {
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
  margin-bottom: 20px;
}

.project-card__link {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: gap 0.2s ease;
}

.project-card__link:hover {
  gap: 8px;
}

/* ========================================
   Contact
   ======================================== */
.contact {
  text-align: center;
  background: var(--color-bg-alt);
}

.contact .section__title::after {
  margin-left: auto;
  margin-right: auto;
}

.contact__text {
  color: var(--color-text-secondary);
  max-width: 480px;
  margin: 0 auto 32px;
}

.contact__email {
  margin-bottom: 32px;
}

.contact__socials {
  display: flex;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
}

.contact__social-link {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: color 0.2s ease;
}

.contact__social-link:hover {
  color: var(--color-text);
}

/* ========================================
   Footer
   ======================================== */
.footer {
  padding: 32px 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer__text {
  font-size: 0.875rem;
  color: var(--color-text-tertiary);
}

/* ========================================
   Scroll Reveal
   ======================================== */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out);
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

.reveal-stagger > .reveal:nth-child(1) { transition-delay: 0ms; }
.reveal-stagger > .reveal:nth-child(2) { transition-delay: 80ms; }
.reveal-stagger > .reveal:nth-child(3) { transition-delay: 160ms; }
.reveal-stagger > .reveal:nth-child(4) { transition-delay: 240ms; }
.reveal-stagger > .reveal:nth-child(5) { transition-delay: 320ms; }
.reveal-stagger > .reveal:nth-child(6) { transition-delay: 400ms; }

/* ========================================
   Reduced Motion
   ======================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ========================================
   Responsive — Mobile
   ======================================== */
@media (max-width: 767px) {
  .nav__toggle {
    display: flex;
  }

  .nav__menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    flex-direction: column;
    justify-content: flex-start;
    padding: 32px 24px;
    gap: 24px;
    background: rgba(250, 250, 250, 0.98);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    transform: translateX(100%);
    transition: transform 0.3s var(--ease-out);
  }

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

  .nav__menu .nav__link {
    font-size: 1.25rem;
  }

  .hero {
    min-height: calc(100vh - var(--nav-height));
    min-height: calc(100dvh - var(--nav-height));
  }

  .bg-blobs__blob {
    filter: blur(60px);
    opacity: 0.3;
  }

  .bg-blobs__blob--1 { width: 350px; height: 350px; }
  .bg-blobs__blob--2 { width: 300px; height: 300px; }
  .bg-blobs__blob--3 { width: 280px; height: 280px; }
}

/* ========================================
   Responsive — Desktop
   ======================================== */
@media (min-width: 768px) {
  .section {
    padding: 120px 0;
  }

  .about__content {
    flex-direction: row;
    gap: 64px;
  }

  .about__text {
    flex: 0.6;
  }

  .about__sidebar {
    flex: 0.35;
  }

  .experience__item {
    flex-direction: column;
    padding-left: 32px;
  }

  .projects__grid {
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  }
}