:root[data-theme="light"] {
  --bg: #fafaf7;
  --bg-nav: #ffffff;
  --text: #14181a;
  --text-muted: #393f3e;
  --accent: #31a96b;
  --border: #e4e4df;
  --photo-bg: #efefea;
}

:root[data-theme="dark"] {
  --bg: #0b0f0e;
  --bg-nav: #05070650;
  --bg-nav: #060907;
  --text: #edefec;
  --text-muted: #c1d5cd;
  --accent: #37d67a;
  --border: #1b211e;
  --photo-bg: #131917;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: "Google Sans", sans-serif;
  transition:
    background 0.25s ease,
    color 0.25s ease;
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
}

/* -------------------- NAVBAR -------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-nav);
  border-bottom: 1px solid var(--border);
  padding: 0.9rem 1.75rem;
}

.nav-home {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.1rem;
  height: 2.1rem;
  border-radius: 6px;
  color: var(--text);
  transition:
    color 0.2s ease,
    background 0.2s ease;
}
.nav-home:hover {
  color: var(--accent);
  background: var(--border);
}
.nav-home svg {
  width: 1.15rem;
  height: 1.15rem;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav-links {
  display: flex;
  gap: 1.75rem;
  font-family: "Google Sans", sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.02em;
}

.nav-links a {
  position: relative;
  color: var(--text-muted);
  padding-bottom: 2px;
  transition: color 0.2s ease;
}
.nav-links a:hover {
  color: var(--text);
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -3px;
  width: 0%;
  height: 1.5px;
  background: var(--accent);
  transition: width 0.2s ease;
}
.nav-links a:hover::after {
  width: 100%;
}

/* Theme toggle switch */
.theme-toggle {
  position: relative;
  width: 2.6rem;
  height: 1.4rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--border);
  cursor: pointer;
  flex-shrink: 0;
}
.theme-toggle::before {
  content: "";
  position: absolute;
  top: 1px;
  left: 1px;
  width: 1.1rem;
  height: 1.1rem;
  border-radius: 50%;
  background: var(--accent);
  transition: transform 0.25s ease;
}
:root[data-theme="light"] .theme-toggle::before {
  transform: translateX(1.2rem);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.3rem;
}
.hamburger span {
  width: 20px;
  height: 2px;
  background: var(--text);
  transition:
    transform 0.2s ease,
    opacity 0.2s ease;
}
.hamburger.open span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.hamburger.open span:nth-child(2) {
  opacity: 0;
}
.hamburger.open span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

@media (max-width: 640px) {
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: var(--bg-nav);
    border-bottom: 1px solid var(--border);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease;
  }
  .nav-links.open {
    max-height: 16rem;
  }
  .nav-links a {
    padding: 0.9rem 1.75rem;
    width: 100%;
    border-top: 1px solid var(--border);
  }
  .hamburger {
    display: flex;
  }
}

/* -------------------- HERO -------------------- */
.hero {
  max-width: 40rem;
  margin: 0 auto;
  padding: 5.5rem 1.5rem 4rem;
  text-align: center;
}

.photo {
  width: 9.5rem;
  height: 9.5rem;
  margin: 0 auto 2rem;
  border-radius: 50%;
  background: var(--photo-bg);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "IBM Plex Mono", monospace;
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero h1 {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 2.4rem;
  letter-spacing: -0.01em;
}

.tagline {
  margin-top: 0.6rem;
  font-family: "Google Sans", sans-serif;
  font-size: 0.85rem;
  font-weight: 450;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.hero-para {
  margin-top: 1.6rem;
  color: var(--text-muted);
  font-size: 1.02rem;
  line-height: 1.65;
}

.spectral-line {
  width: 4rem;
  height: 2px;
  background: var(--accent);
  margin: 2.75rem auto 0;
}

/* -------------------- ABOUT PREVIEW -------------------- */
.about-preview {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  max-width: 34rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  border-top: 1px solid var(--border);
}

.about-preview h2 {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 1.6rem;
  margin-bottom: 1.1rem;
}

.about-preview p {
  color: var(--text-muted);
  line-height: 1.7;
  font-size: 1rem;
}

.link-more {
  display: inline-block;
  margin-top: 1.6rem;
  font-family: "Google Sans", sans-serif;
  font-size: 0.82rem;
  color: var(--accent);
  border-bottom: 1px solid var(--accent);
  padding-bottom: 2px;
}
.link-more:hover {
  opacity: 0.75;
}

/* -------------------- ABOUT PAGE -------------------- */
.about {
  display: flex;
  min-height: 100vh;
  flex-direction: column;
  /* align-items: center; */
  max-width: 60rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  gap: 1.5rem;
}

.about h1 {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 2rem;
  margin-bottom: 0.5rem;
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 3px;
  text-underline-offset: 10px;
}

.about p {
  color: var(--text-muted);
  line-height: 1.4;
  font-size: 1rem;
  text-align: justify;
  /* text-indent: 3rem; */
  margin: 0;
}

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

/* -------------------- RESEARCH -------------------- */
.research {
  display: flex;
  min-height: 100vh;
  flex-direction: column;
  /* align-items: center; */
  max-width: 60rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  gap: 1.5rem;
}

.research h1 {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 2rem;
  margin-bottom: 0.5rem;
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 3px;
  text-underline-offset: 10px;
}

.research p {
  color: var(--text-muted);
  line-height: 1.4;
  font-size: 1rem;
  text-align: justify;
  margin: 0;
}

.research h3 {
  font-family: "Fraunces", serif;
  font-weight: 400;
  font-size: 1.2rem;
  margin-top: 1.5rem;
  margin-bottom: -13px;
}

.research .dot {
  font-size: 1rem;
  margin-right: 2px;
  color: var(--accent);
}

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

/* -------------------- WRITING -------------------- */
.writing {
  display: flex;
  min-height: 100vh;
  flex-direction: column;
  /* align-items: center; */
  max-width: 60rem;
  margin: 0 auto;
  padding: 3rem 1.5rem;
  gap: 1.5rem;
}

.writing h1 {
  font-family: "Fraunces", serif;
  font-weight: 500;
  font-size: 2rem;
  margin-bottom: 0.5rem;
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-decoration-thickness: 3px;
  text-underline-offset: 10px;
}

.writing p {
  color: var(--text-muted);
  line-height: 1.4;
  font-size: 1rem;
  text-align: justify;
  /* text-indent: 3rem; */
  margin: 0;
}

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

.writing li::marker {
  color: var(--accent);
  font-size: 1.5rem;
}

.writing li a {
  position: relative;
  color: var(--text-muted);
  padding-bottom: 2px;
  text-decoration: none;
  transition: color 0.2s ease;
}

.writing li a:hover {
  color: var(--text);
}

.writing li a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 1px;
  width: 100%;
  height: 1.5px;
  background: var(--accent);
  opacity: 0;
  transition: opacity 0.2s ease;
}

.writing li a:hover::after {
  opacity: 1;
}

/* -------------------- FOOTER -------------------- */
.footer {
  border-top: 1px solid var(--border);
  padding: 2.75rem 1.5rem 3rem;
}

.footer-inner {
  max-width: 34rem;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  text-align: center;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 1.6rem;
}

.footer-links a {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text-muted);
  font-family: "Google Sans", sans-serif;
  font-size: 0.78rem;
  letter-spacing: 0.02em;
  transition: color 0.2s ease;
}

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

.footer-links svg {
  width: 1.05rem;
  height: 1.05rem;
}

.footer-note {
  color: var(--text-muted);
  font-family: "Google Sans", sans-serif;
  font-size: 0.72rem;
  letter-spacing: 0.02em;
  opacity: 0.75;
}

@media (max-width: 480px) {
  .footer-links {
    flex-direction: column;
    gap: 1rem;
  }
}