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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

input, button, textarea, select {
  font: inherit;
}

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

ul, ol {
  list-style: none;
}

/* ===== Custom Properties ===== */
:root {
  /* Palette — warm light theme with amber accents */
  --color-bg: #FAFAF8;
  --color-bg-alt: #F0EDE6;
  --color-surface: #FFFFFF;
  --color-text: #1C1917;
  --color-text-muted: #57534E;
  --color-text-light: #78716C;
  --color-accent: #D97706;
  --color-accent-hover: #B45309;
  --color-accent-light: #FEF3C7;
  --color-accent-subtle: #FFFBEB;
  --color-border: #E7E5E4;
  --color-border-strong: #D6D3D1;

  /* Typography */
  --font-sans: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Cascadia Code", "Fira Code", "Consolas", monospace;

  --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: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;

  --leading-tight: 1.15;
  --leading-normal: 1.6;

  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-5xl: 8rem;

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 800px;
  --nav-height: 64px;
  --border-radius: 6px;
  --border-radius-lg: 12px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(28, 25, 23, 0.05);
  --shadow-md: 0 4px 12px rgba(28, 25, 23, 0.08);
  --shadow-lg: 0 8px 24px rgba(28, 25, 23, 0.1);
}

/* ===== Base / Typography ===== */
body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: var(--weight-normal);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-mono);
  font-weight: var(--weight-bold);
  line-height: var(--leading-tight);
  letter-spacing: -0.02em;
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }

p + p {
  margin-top: var(--space-md);
}

strong {
  font-weight: var(--weight-semibold);
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  padding: 0.15em 0.4em;
  background: var(--color-bg-alt);
  border-radius: 3px;
}

/* ===== Layout ===== */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--space-xl);
}

.container--narrow {
  max-width: var(--container-narrow);
}

main {
  padding-top: var(--nav-height);
}

section {
  padding-block: var(--space-3xl);
}

section + section {
  border-top: 1px solid var(--color-border);
}

/* ===== Navigation ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  background: rgba(250, 250, 248, 0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav__logo {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: var(--weight-bold);
  letter-spacing: -0.03em;
  color: var(--color-text);
  transition: color var(--transition-fast);
}

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

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

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

.nav__link {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-muted);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--border-radius);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

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

.nav__link--active {
  background: var(--color-accent-subtle);
}

.nav__toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-sm);
  color: var(--color-text);
}

.nav__toggle svg {
  width: 24px;
  height: 24px;
}

/* Mobile nav */
@media (max-width: 768px) {
  .nav__toggle {
    display: block;
  }

  .nav__links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-lg);
    gap: var(--space-sm);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--transition-base), opacity var(--transition-base);
  }

  .nav__links--open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .nav__link {
    width: 100%;
    padding: var(--space-sm) var(--space-md);
    font-size: var(--text-base);
  }
}

/* ===== Hero ===== */
.hero {
  position: relative;
  padding-block: var(--space-xl) var(--space-2xl);
  overflow: hidden;
}

.hero__bg {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle, var(--color-border) 1px, transparent 1px);
  background-size: 24px 24px;
  opacity: 0.5;
}

.hero__inner {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 370px;
  gap: var(--space-2xl);
  align-items: center;
  max-width: 1060px;
  margin-inline: auto;
}

@media (max-width: 900px) {
  .hero__inner {
    grid-template-columns: 1fr;
  }

  .hero__image {
    max-width: 360px;
  }
}

.hero__content {
  max-width: 720px;
}

.hero__image a {
  display: block;
  border: 4px solid #F6D68A;
  border-radius: var(--border-radius-lg);
  padding: var(--space-md) 10%;
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.hero__image a:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.hero__image img {
  max-width: 270px;
  width: 100%;
  height: auto;
  border-radius: var(--border-radius-md);
  margin-inline: auto;
}

.hero__image-tag {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-text-light);
  text-align: center;
  margin-top: var(--space-sm);
}

.hero__label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-accent);
  background: var(--color-accent-light);
  padding: var(--space-xs) var(--space-md);
  border-radius: 100px;
  margin-bottom: var(--space-lg);
}

.hero__title {
  font-size: clamp(var(--text-3xl), 4.5vw, var(--text-5xl));
  margin-bottom: var(--space-lg);
}

.hero__title em {
  font-style: normal;
  color: var(--color-accent);
}

.hero__subtitle {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 520px;
  margin-bottom: var(--space-xl);
}

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

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

.btn--primary:hover {
  background: var(--color-accent-hover);
  box-shadow: var(--shadow-md);
}

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

.btn--outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== Section Headings ===== */
.back-link {
  display: inline-block;
  margin-bottom: var(--space-lg);
  font-size: var(--text-sm);
  font-family: var(--font-mono);
  color: var(--color-text-light);
  text-decoration: none;
  transition: color 0.2s;
}
.back-link:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

.section-header {
  margin-bottom: var(--space-2xl);
}

.section-header__label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-sm);
}

.section-header__title {
  margin-bottom: var(--space-md);
}

.section-header__desc {
  color: var(--color-text-muted);
  max-width: 560px;
}

/* ===== Direction Cards (Home page) ===== */
.direction-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-xl);
}

.direction-card {
  position: relative;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  padding: var(--space-2xl);
  transition: border-color var(--transition-base), box-shadow var(--transition-base), transform var(--transition-base);
}

.direction-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.direction-card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent-light);
  color: var(--color-accent);
  border-radius: var(--border-radius);
  margin-bottom: var(--space-lg);
  font-size: var(--text-xl);
}

.direction-card__title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-sm);
}

.direction-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
}

.direction-card__link {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  transition: gap var(--transition-fast);
}

.direction-card:hover .direction-card__link {
  gap: var(--space-sm);
}

/* ===== Project Cards ===== */
.project-filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-bottom: var(--space-2xl);
}

.filter-btn {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  font-weight: var(--weight-medium);
  padding: var(--space-sm) var(--space-lg);
  border-radius: 100px;
  border: 1px solid var(--color-border);
  background: transparent;
  color: var(--color-text-muted);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.filter-btn--active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: white;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-xl);
}

.project-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  transition: border-color var(--transition-base), box-shadow var(--transition-base), transform var(--transition-base);
}

.project-card:hover {
  border-color: var(--color-accent);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.project-card__image {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 10;
  background: var(--color-bg-alt);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-light);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  border-bottom: 1px solid var(--color-border);
}

.project-badge {
  position: absolute;
  z-index: 1;
  top: var(--space-sm);
  right: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-semibold);
  padding: 3px 10px;
  border-radius: 100px;
  letter-spacing: 0.02em;
}

.project-badge--research {
  background: var(--color-accent);
  color: white;
}

.project-badge--class {
  background: var(--color-border-strong);
  color: var(--color-text);
}

.project-badge--personal {
  background: var(--color-text);
  color: var(--color-bg);
}

.project-card__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
  inset: 0;
}

.project-card__body {
  padding: var(--space-lg);
}

.project-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-bottom: var(--space-sm);
}

.tag {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  color: var(--color-accent);
  background: var(--color-accent-subtle);
  padding: 2px 8px;
  border-radius: 100px;
}

.project-card__title {
  font-size: var(--text-lg);
  margin-bottom: var(--space-sm);
}

.project-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ===== Project Columns Layout ===== */
.project-columns {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: var(--space-xl);
  align-items: start;
}

.project-column {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  padding: var(--space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.project-column--research {
  border-top: 5px solid var(--color-accent);
}

.project-column--personal {
  border-top: 5px solid var(--color-text);
}

.project-column--class {
  border-top: 5px solid var(--color-border-strong);
}

.project-column__heading {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  font-weight: var(--weight-semibold);
  letter-spacing: 0.02em;
  margin: 0;
}

.project-column__empty {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-align: center;
  padding: var(--space-2xl) var(--space-md);
  margin: 0;
  font-style: italic;
}

.project-column .project-card {
  flex: 0 0 auto;
}

@media (max-width: 1024px) {
  .project-columns {
    grid-template-columns: 1fr;
    gap: var(--space-2xl);
  }
}

/* ===== About Page ===== */
.about-intro {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: var(--space-3xl);
  align-items: start;
}

.about-intro__text {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
}

.about-intro__text p + p {
  margin-top: var(--space-md);
}

.about-intro__photo {
  width: 100%;
  position: relative;
  aspect-ratio: 3 / 4;
  margin-top: -80px;
}

@media (max-width: 768px) {
  .about-intro {
    grid-template-columns: 1fr;
  }
  .about-intro__photo {
    margin-top: 0;
    max-width: 300px;
    margin-inline: auto;
  }
  .about-photo__art--painting {
    bottom: -80px;
    left: 0;
  }
  .about-photo__art--drawing {
    bottom: -100px;
    right: 0;
  }
}

.about-photo__headshot {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--color-border);
}

.about-photo__art {
  position: absolute;
  width: 70%;
  border-radius: var(--border-radius-md);
  border: 3px solid white;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.2);
  object-fit: cover;
}

.about-photo__art--painting {
  bottom: -110px;
  left: -30px;
}

.about-photo__art--drawing {
  bottom: -130px;
  right: -10px;
}

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-lg);
}

.skill-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-lg);
  padding: var(--space-lg);
  border-left: 3px solid var(--color-accent);
}

.skill-card__title {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-sm);
}

.skill-card__items {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.8;
}

/* ===== Resume Page ===== */
.resume-download {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-3xl);
  padding: var(--space-lg);
  background: var(--color-accent-subtle);
  border: 1px solid var(--color-accent-light);
  border-radius: var(--border-radius-lg);
}

.resume-download__text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.timeline {
  position: relative;
  padding-left: var(--space-2xl);
}

.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--color-border);
}

.timeline__item {
  position: relative;
  padding-bottom: var(--space-2xl);
}

.timeline__item:last-child {
  padding-bottom: 0;
}

.timeline__item::before {
  content: "";
  position: absolute;
  left: calc(-1 * var(--space-2xl) - 4px);
  top: 6px;
  width: 10px;
  height: 10px;
  background: var(--color-accent);
  border-radius: 50%;
  border: 2px solid var(--color-bg);
}

.timeline__date {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-xs);
}

.timeline__title {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-xs);
}

.timeline__org {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-sm);
}

.timeline__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-2xl);
  margin-top: var(--space-2xl);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.footer__copy {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.footer__links {
  display: flex;
  gap: var(--space-lg);
}

.footer__link {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

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

/* ===== Responsive ===== */
@media (max-width: 640px) {
  :root {
    --space-4xl: 3rem;
    --space-5xl: 4rem;
  }

  h1 { font-size: var(--text-3xl); }
  h2 { font-size: var(--text-2xl); }

  .container {
    padding-inline: var(--space-md);
  }

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

  .footer__inner {
    flex-direction: column;
    text-align: center;
  }
}