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

button,
input,
textarea {
  font-family: inherit;
}

:root {
  --header-height: 4.375rem;
  --user-font-size: 1rem;

  /* Backgrounds */
  --bg-primary: hsla(222, 47%, 16%, 1);
  --bg-secondary: hsla(221, 39%, 16%, 1);
  --bg-card: hsla(217, 33%, 22%, 1);
  --bg-border: hsla(215, 25%, 33%, 1);
  --bg-header: hsla(222, 42%, 21%, 0.92);
  --bg-input: hsla(0, 0%, 100%, 0.05);

  /* Text */
  --text-primary: hsla(210, 40%, 98%, 1);
  --text-secondary: hsla(213, 27%, 84%, 1);
  --text-muted: hsla(215, 20%, 65%, 1);

  /* Accent colors */
  --accent: hsla(208, 40%, 54%, 1);
  --accent-dark: hsla(206, 37%, 46%, 1);
  --accent-light: hsla(180, 40%, 64%, 1);
  --accent-subtle: hsla(208, 40%, 54%, 0.15);
  --accent-focus: hsla(208, 40%, 54%, 0.25);
  --accent-glow: hsla(180, 40%, 64%, 0.4);
  --accent-hover-shadow: 0 0.5rem 1.25rem hsla(208, 40%, 54%, 0.35);

  /* Status */
  --color-error: hsla(0, 84%, 60%, 1);
  --color-success: hsla(142, 71%, 45%, 0.4);
  --color-success-text: hsla(142, 69%, 58%, 1);

  /* Effects */
  --radius: 1rem;
  --shadow: 0 0.625rem 1.875rem hsla(0, 0%, 0%, 0.25);
  --shadow-dark: hsla(0, 0%, 0%, 0.5);
  --shadow-hover: 0 0.938rem 2.188rem var(--accent-focus);
}

/* LIGHT THEME: applied when theme="light" */
:root[data-theme="light"] {
  /* Warm dark-cream palette instead of the previous near-white/blue-gray
     one -- same hue family (a warm, slightly yellow-orange tan) across
     all four background tokens, just at different lightness levels, so
     --bg-card still reads as "the lighter surface" against
     --bg-primary/--bg-secondary underneath it. */
  --bg-primary: hsla(40, 38%, 90%, 1);
  --bg-secondary: hsla(36, 32%, 85%, 1);
  --bg-card: hsla(42, 45%, 96%, 1);
  --bg-border: hsla(35, 22%, 76%, 1);
  --bg-header: hsla(40, 38%, 90%, 0.85);
  --bg-input: hsla(30, 40%, 20%, 0.05);

  --text-primary: hsla(222, 47%, 11%, 1);
  --text-secondary: hsla(215, 25%, 27%, 1);
  --text-muted: hsla(215, 16%, 47%, 1);

  --accent: hsla(203, 38%, 40%, 1);
  --accent-dark: hsla(203, 39%, 33%, 1);
  --accent-light: hsla(182, 42%, 32%, 1);

  --shadow: 0 0.625rem 1.875rem hsla(30, 30%, 20%, 0.14);
  --shadow-dark: hsla(30, 30%, 20%, 0.2);
}

/* GLOBAL: page-wide typography, background, and base behavior */
html {
  font-size: 1rem;
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  /* Plain top-to-bottom gradient only -- the dot grid was removed in
     favor of the animated particle canvas in the hero section
     (see #hero-canvas / main.js), so there's no need for both a static
     dot texture AND the moving particles competing for attention. */
  background-image: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  background-size: 100% 100%;
  background-attachment: local;
  color: var(--text-primary);
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.6;
  transition:
    background-color 0.3s ease,
    color 0.3s ease;
}

body.modal-open {
  overflow: hidden;
}

/* ACCESSIBILITY: keyboard skip link and focus-friendly helpers */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--accent);
  color: var(--text-primary);
  padding: 0.5rem 1.25rem;
  border-radius: 0 0 var(--radius) var(--radius);
  font-weight: 600;
  z-index: 9999;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
}

:focus-visible {
  outline: 0.2rem solid var(--accent-light);
  outline-offset: 0.2rem;
}
.sr-only {
  position: absolute;
  width: 0.063rem;
  height: 0.063rem;
  padding: 0;
  margin: -0.063rem;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* SCROLL PROGRESS BAR: fixed indicator updated by main.js */
#progress {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 0.188rem;
  background: linear-gradient(90deg, var(--accent), var(--accent-light));
  z-index: 1001;
  transition: width 0.1s linear;
}

/* COPY TOAST: temporary feedback after copying the email address */
#copy-toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(1rem);
  background: var(--bg-card);
  color: var(--text-primary);
  border: 0.063rem solid var(--accent);
  border-radius: var(--radius);
  padding: 0.75rem 1.5rem;
  font-size: 0.9rem;
  font-weight: 600;
  opacity: 0;
  pointer-events: none;
  z-index: 9999;
  transition:
    opacity 0.3s ease,
    transform 0.3s ease;
}

#copy-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* REVEAL ANIMATIONS: scroll-triggered entrance states */
.reveal {
  opacity: 0;
  transform: translateY(1.5rem);
  transition:
    opacity 0.6s ease,
    transform 0.6s ease;
}

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

/* Stagger reveal timing for card grids */
.skills-grid .reveal:nth-child(2) {
  transition-delay: 0.08s;
}
.skills-grid .reveal:nth-child(3) {
  transition-delay: 0.16s;
}
.skills-grid .reveal:nth-child(4) {
  transition-delay: 0.24s;
}
.skills-grid .reveal:nth-child(5) {
  transition-delay: 0.32s;
}
.skills-grid .reveal:nth-child(6) {
  transition-delay: 0.4s;
}
.skills-grid .reveal:nth-child(7) {
  transition-delay: 0.48s;
}

.highlights-grid .reveal:nth-child(2) {
  transition-delay: 0.08s;
}
.highlights-grid .reveal:nth-child(3) {
  transition-delay: 0.16s;
}
.highlights-grid .reveal:nth-child(4) {
  transition-delay: 0.24s;
}

/* HEADER: fixed top navigation bar */
header {
  position: fixed;
  top: 0;
  width: 100%;
  height: var(--header-height);
  background-color: var(--bg-header);
  -webkit-backdrop-filter: blur(0.5rem);
  backdrop-filter: blur(0.5rem);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
  padding: 0 2rem;
  border-bottom: 0.063rem solid var(--bg-border);
  box-shadow: var(--shadow);
  z-index: 1000;
}

/* LOGO: brand mark sizing and hover behavior */
.logo {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
}

.logo img {
  height: 2.75rem;
  width: auto;
  display: block;
  transition: transform 0.3s ease;
}

.logo:hover img {
  transform: translateY(-0.125rem) scale(1.03);
}

header nav {
  display: flex;
  gap: 2rem;
}

header a {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.9rem;
  padding-bottom: 0.2rem;
  border-bottom: 0.125rem solid transparent;
  transition:
    color 0.3s ease,
    border-color 0.3s ease;
}

header a:hover,
header a.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* THEME TOGGLE: dark/light mode button */
#theme-toggle,
#chess,
#nav-toggle {
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 50%;
  border: 0.063rem solid var(--bg-border);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 1.1rem;
  line-height: 1;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition:
    border-color 0.3s ease,
    transform 0.3s ease,
    background-color 0.3s ease;
}

#theme-toggle:hover,
#chess:hover,
#nav-toggle:hover {
  border-color: var(--accent);
  transform: translateY(-0.125rem);
}

/* NAV TOGGLE: hamburger button, only shown on small screens */
#nav-toggle {
  display: none;
}

.header-controls {
  display: inline-flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.625rem;
  flex: 0 1 auto;
  margin-left: auto;
  min-width: 0;
}

/* TEXT SIZE CONTROL: fixed-size header slider for readable content scaling */
.control-panel {
  display: inline-flex;
  align-items: center;
  flex: 0 1 14.375rem;
  max-width: 14.375rem;
  min-width: 0;
  gap: 0.438rem;
  margin-left: 0;
  font-size: 0.9rem;
  line-height: 1.2;
  white-space: nowrap;
  color: var(--text-muted);
  font-weight: 600;
}

.control-panel label,
.control-panel span {
  flex: 0 0 auto;
  color: inherit;
  font: inherit;
}

.control-panel input[type="range"] {
  flex: 1 1 5.625rem;
  width: 5.625rem;
  min-width: 4.375rem;
  max-width: 6.875rem;
}

#sizeValue {
  width: 2.125rem;
  text-align: right;
}

#chess img {
  width: 1.5rem;
  height: 1.5rem;
  object-fit: contain;
}
/* =====================
   GENERAL SECTION RULES
   ===================== */
section {
  padding: 5rem max(2rem, calc(50% - 38rem));
  scroll-margin-top: var(--header-height);
}

/* Shared section intro block used by major content sections */
.section-intro {
  text-align: center;
  max-width: 50rem;
  margin: 0 auto 2.5rem;
}

.section-intro h2 {
  font-size: 2rem;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.section-intro .section-subtitle {
  color: var(--text-secondary);
  font-size: 1.05rem;
  font-weight: 500;
  margin-bottom: 0.4rem;
}

.section-intro .section-desc {
  color: var(--text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ============
   HERO SECTION
   ============ */
#home {
  position: relative;
  min-height: 40.88rem;
  display: flex;
  flex-direction: row;
  padding: 7.5rem max(2rem, calc(50% - 38rem));
  text-align: center;
  align-items: center;
  justify-content: center;
  gap: 4rem;
  margin-top: var(--header-height);
  overflow: hidden;
}

#hero-canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

#home > img,
#home > .home-content {
  position: relative;
  z-index: 1;
}

#home img {
  width: 18.75rem;
  height: 18.75rem;
  object-fit: cover;
  border-radius: 50%;
  border: 0.313rem solid var(--accent);
  outline: 0.5rem solid var(--accent-light);
  outline-offset: 0.625rem;
  box-shadow:
    0 0 0 1.25rem var(--bg-card),
    0 0 0 1.5rem var(--bg-border),
    0 0.938rem 2.5rem var(--shadow-dark),
    0 0 2.188rem var(--accent-glow);
}

.home-content {
  max-width: 43.75rem;
  text-align: center;
}

.home-content h1 {
  font-size: 4rem;
  margin-bottom: 0.5rem;
}

.home-content h2 {
  color: var(--accent);
  font-size: 2rem;
  margin-bottom: 1rem;
  min-height: 2.8rem;
}

.home-content h3 {
  color: var(--accent);
  font-size: 1.75rem;
  margin-bottom: 1rem;
}

.home-content p {
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: 1.2rem;
}

.home-content h1 {
  font-size: clamp(
    2.5rem,
    calc(var(--user-font-size) * 4),
    5rem
  );
}

.home-content h2 {
  font-size: clamp(
    1.35rem,
    calc(var(--user-font-size) * 2),
    2.5rem
  );
}

/* TYPEWRITER CURSOR: visual caret for animated role text */
.typewriter-cursor {
  display: inline-block;
  color: var(--accent);
  margin-left: 0.125rem;
  animation: blink 0.75s step-end infinite;
}

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

/* =======
   BUTTONS
   ======= */
.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
  justify-content: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 12rem;
  padding: 0.875rem 1.5rem;
  border: none;
  border-radius: 0.75rem;
  background: var(--accent);
  color: var(--text-primary);
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition:
    background-color 0.3s ease,
    transform 0.3s ease,
    box-shadow 0.3s ease;
}

.btn:hover {
  transform: translateY(-0.125rem);
  background: var(--accent-dark);
  box-shadow: var(--accent-hover-shadow);
}

.btn:active {
  transform: translateY(0);
}

.btn-secondary {
  background: transparent;
  border: 0.125rem solid var(--accent);
  color: var(--accent);
}

.btn-secondary:hover {
  background: var(--accent-subtle);
}

.btn-outline {
  background: transparent;
  border: 0.125rem solid var(--text-muted);
  color: var(--text-secondary);
}

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

/* Shared elevated-card surface and interaction */
#about,
.highlight-card,
.skills-card,
.project-preview-card,
.jobs-card,
.edu-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition:
    transform 0.3s ease,
    box-shadow 0.3s ease;
}

#about:hover,
.highlight-card:hover,
.skills-card:hover,
.project-preview-card:hover,
.jobs-card:hover,
.edu-card:hover {
  transform: translateY(-0.5rem);
  box-shadow: var(--shadow-hover);
}

.highlights-grid,
.skills-grid,
.edu-div {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 2rem;
}

/* =============
   ABOUT SECTION
   ============= */
#about {
  max-width: 62.5rem;
  margin: 0 auto;
  scroll-margin-top: var(--header-height);
  padding: 3rem;
}

#about h2 {
  font-size: 2rem;
  color: var(--accent);
  text-align: center;
  margin-bottom: 1.5rem;
}

#about p {
  text-align: left;
  max-width: 50rem;
  margin: 0 auto 1.25rem auto;
  color: var(--text-secondary);
}

/* ================
   HIGHLIGHTS BAR
   ================ */
#highlights {
  padding: 2rem max(2rem, calc(50% - 38rem));
  scroll-margin-top: var(--header-height);
}

.highlight-card {
  width: 13.75rem;
  min-height: 8.75rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.highlight-card h3 {
  color: var(--accent);
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.highlight-card p {
  color: var(--text-secondary);
}

/* ==============
   SKILLS SECTION
   ============== */
.skills-card {
  width: 20rem;
  min-height: 17.5rem;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 1.5rem;
  gap: 0.5rem;
}

.skills-card h3 {
  color: var(--accent);
  font-size: 1.25rem;
  font-weight: 700;
}

.skills-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.5;
}

.keyword {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: auto;
  padding-top: 0.75rem;
}

.keyword span {
  position: relative;
  overflow: hidden;
  background-color: var(--accent-subtle);
  color: var(--accent-light);
  border: 0.063rem solid var(--accent);
  border-radius: 624.938rem;
  padding: 0.3rem 0.75rem;
  font-size: 0.8rem;
  font-weight: 600;
  transition:
    background-color 0.3s ease,
    color 0.3s ease,
    transform 0.3s ease;
  cursor: default;
  -webkit-user-select: none;
  user-select: none;
}

.keyword span:hover {
  background-color: var(--accent);
  color: var(--text-primary);
  transform: translateY(-0.125rem);
}

/* Keyword badge ripple effect injected by main.js */
.ripple-effect {
  position: absolute;
  border-radius: 50%;
  background: hsla(0, 0%, 100%, 0.35);
  pointer-events: none;
  animation: ripple-out 0.55s ease-out forwards;
}

@keyframes ripple-out {
  from {
    transform: scale(0);
    opacity: 1;
  }
  to {
    transform: scale(3);
    opacity: 0;
  }
}

/* ================
   PROJECTS SECTION: responsive preview cards with theme-aware image fades
   ================ */
.projects-section {
  padding-top: 2rem;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 22rem), 1fr));
  gap: 2rem;
  max-width: 58rem;
  margin: 0 auto;
}

.project-preview-card {
  position: relative;
  display: flex;
  flex-direction: column;
  height: 100%;
  border: 0.063rem solid var(--bg-border);
  overflow: hidden;
}

.project-preview-image {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--bg-card);
}

.project-preview-image::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 42%;
  background: linear-gradient(
    180deg,
    hsla(217, 33%, 19%, 0),
    var(--bg-card) 84%
  );
  pointer-events: none;
}

.project-preview-image.project-preview-image-mobile img {
  object-fit: contain;
  background: hsla(216, 9%, 10%, 1);
}
.project-preview-image img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.project-preview-card figcaption {
  position: relative;
  z-index: 1;
  display: flex;
  flex: 1;
  flex-direction: column;
  gap: 0.5rem;
  min-height: 9.5rem;
  padding: 0 1.25rem 1.25rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.5;
}

.project-preview-card figcaption h3 {
  color: var(--accent);
  font-size: 1rem;
  line-height: 1.25;
}

:root[data-theme="light"] .project-preview-image::after {
  background: linear-gradient(180deg, hsla(0, 0%, 100%, 0), var(--bg-card) 84%);
}

.project-highlights {
  padding-left: 1.25rem;
  color: var(--text-secondary);
}

.project-highlights li {
  margin-bottom: 0.4rem;
}

.projects-grid > .project-preview-card:last-child:nth-child(odd) {
  grid-column: 1 / -1;
  width: min(100%, 28rem);
  justify-self: center;
}

/* =================
   EXPERIENCE SECTION
   ================= */
.experience-group-title {
  max-width: 50rem;
  margin: 2.5rem auto 1rem;
  color: var(--accent);
  font-size: 1.3rem;
}

.section-intro + .experience-group-title {
  margin-top: 0;
}

.jobs-grid {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  max-width: 50rem;
  margin: 0 auto;
}

.jobs-card {
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.jobs-card .job-title {
  color: var(--accent);
  font-size: 1.2rem;
  font-weight: 700;
}

.card-date {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  background: var(--accent-subtle);
  border: 0.063rem solid var(--accent);
  border-radius: 624.938rem;
  padding: 0.2rem 0.75rem;
  color: var(--accent-light);
  font-size: 0.8rem;
  font-weight: 600;
  width: fit-content;
}

.jobs-card > p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 0.5rem;
}

.impact-label {
  color: var(--text-primary);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-top: 0.5rem;
}

.jobs-card ol {
  color: var(--text-secondary);
  padding-left: 1.25rem;
  font-size: 0.9rem;
}

.jobs-card li {
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

/* ======================
   CERTIFICATIONS SECTION
   ====================== */
.cert-images {
  display: flex;
  flex-direction: row;
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

/* ONLINE LEARNING: compact course badges designed to scale as more items are added */
.online-learning {
  max-width: 72rem;
  margin: 2rem auto 0;
  text-align: center;
}

.online-learning h3 {
  color: var(--accent);
  font-size: 1.2rem;
  margin-bottom: 1rem;
}

.learning-badges {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1.25rem;
}

.learning-badge {
  position: relative;
  display: grid;
  place-items: center;
  width: min(100%, 14rem);
  margin: 0;
  isolation: isolate;
}

.learning-course-label {
  position: absolute;
  right: -0.75rem;
  top: 50%;
  z-index: 2;
  width: 5.9rem;
  min-height: 6.75rem;
  transform: translateY(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 0.55rem 0.75rem 1.1rem;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  color: var(--text-primary);
  border: 0.063rem solid hsla(0, 0%, 100%, 0.24);
  border-radius: 0 999rem 999rem 0;
  box-shadow: var(--shadow);
  font-size: 0.72rem;
  font-weight: 700;
  line-height: 1.25;
  text-align: left;
}

#certificates .learning-badge img {
  position: relative;
  z-index: 1;
  width: 10.5rem;
  height: 10.5rem;
  aspect-ratio: 1;
  object-fit: cover;
  border-radius: 50%;
  border: 0.18rem solid var(--bg-border);
  box-shadow:
    var(--shadow),
    0 0 0 0.45rem var(--bg-card);
}
#certificates .cert-images img {
  width: clamp(10rem, 19.2rem, 16rem);
  height: auto;
  aspect-ratio: 1;
  object-fit: contain;
  padding: 1rem;
}

/* =================
   EDUCATION SECTION
   ================= */
.edu-card {
  width: 22rem;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.edu-card h3 {
  color: var(--accent);
  font-size: 1.2rem;
  font-weight: 700;
}

.edu-card h4 {
  color: var(--accent-light);
  font-size: 0.95rem;
  font-weight: 600;
}

.edu-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ===============
   CONTACT SECTION
   =============== */
.contact-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 2.5rem;
}

.contact-card {
  max-width: 50rem;
  margin: 0 auto;
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 2rem;
  box-shadow: var(--shadow);
}

/* FORM FEEDBACK: success and error states for contact submission */
.form-feedback {
  border-radius: 0.75rem;
  padding: 1rem;
  margin-bottom: 1rem;
  font-weight: 600;
  text-align: center;
  display: none;
}

.form-feedback.success {
  display: block;
  background: hsla(142, 71%, 45%, 0.1);
  border: 0.063rem solid var(--color-success);
  color: var(--color-success-text);
}

.form-feedback.error {
  display: block;
  background: hsla(0, 84%, 60%, 0.1);
  border: 0.063rem solid var(--color-error);
  color: var(--color-error);
}

#contact-form {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.form-group {
  display: flex;
  flex-direction: column;
}

.form-group label {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
}

.form-group input,
.form-group textarea {
  background: var(--bg-input);
  border: 0.125rem solid transparent;
  border-radius: 0.75rem;
  padding: 1rem;
  color: var(--text-primary);
  font-size: 1rem;
  transition:
    border-color 0.3s ease,
    box-shadow 0.3s ease;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-muted);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 0.2rem var(--accent-focus);
}

input:invalid:focus,
textarea:invalid:focus {
  border-color: var(--color-error);
}

input:user-valid,
textarea:user-valid {
  border-color: var(--color-success);
}

#contact button {
  align-self: center;
  min-width: 12rem;
}

/* ======
   FOOTER
   ====== */
footer {
  text-align: center;
  padding: 2.5rem max(2rem, calc(50% - 38rem));
  color: var(--text-muted);
  border-top: 0.063rem solid var(--bg-border);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: center;
}

.footer-links {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  justify-content: center;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color 0.3s ease;
}

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

.footer-built {
  font-size: 0.8rem;
  color: var(--bg-border);
}

/* ===========
   BACK TO TOP
   =========== */
#back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  background: var(--accent);
  color: var(--text-primary);
  border: none;
  cursor: pointer;
  font-size: 1.25rem;
  line-height: 1;
  opacity: 0;
  transform: translateY(1rem);
  transition:
    opacity 0.3s ease,
    transform 0.3s ease,
    background-color 0.3s ease;
  z-index: 998;
  display: flex;
  align-items: center;
  justify-content: center;
}

#back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
}

#back-to-top:hover {
  background: var(--accent-dark);
}

/* ========
   DOT NAV
   ======== */
.dot-nav {
  position: fixed;
  right: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  z-index: 999;
}

.dot-nav-item {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--bg-border);
  display: block;
  text-decoration: none;
  transition:
    background-color 0.3s ease,
    transform 0.3s ease;
}

.dot-nav-item:hover,
.dot-nav-item.active {
  background: var(--accent);
  transform: scale(1.6);
}

/* =============
   MEDIA QUERIES
   ============= */
@media (max-width: 56rem) {
  .header-controls {
    margin-left: 0;
  }

  header {
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 0.75rem;
    height: auto;
    min-height: var(--header-height);
    padding-top: 0.5rem;
    padding-bottom: 0.5rem;
  }

  /* Collapse the nav behind the hamburger button */
  #nav-toggle {
    display: inline-flex;
  }

  header nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: center;
    gap: 1.25rem;
    padding: 1.25rem 0;
    background-color: var(--bg-header);
    -webkit-backdrop-filter: blur(0.5rem);
    backdrop-filter: blur(0.5rem);
    box-shadow: var(--shadow);
  }

  header nav.open {
    display: flex;
  }

  #theme-toggle {
    margin-left: 0;
  }

  .control-panel {
  flex: 0 1 13.75rem;
  max-width: 13.75rem;
}

@media (max-width: 36rem) {
  .control-panel {
    max-width: 9rem;
  }

  .control-panel label {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
  }
}
}
@media (max-width: 48rem) {
  #home {
    flex-direction: column;
    text-align: center;
  }

  .home-content {
    max-width: 100%;
  }

  .btn-group {
    justify-content: center;
  }

  .skills-card,
  .jobs-card,
  .edu-card {
    width: 100%;
  }

  header {
    padding: 0.5rem 1rem;
    gap: 0.75rem;
  }

  .logo img {
    height: 2.25rem;
  }

  .dot-nav {
    display: none;
  }
}

/* USER TEXT SIZE: late cascade overrides controlled by the header slider */
section,
#highlights,
footer {
  font-size: var(--user-font-size);
  transition: font-size 0.2s ease;
}

.home-content h1 {
  font-size: calc(var(--user-font-size) * 4);
}
.home-content h2 {
  font-size: calc(var(--user-font-size) * 2);
}
.home-content p {
  font-size: calc(var(--user-font-size) * 1.2);
}
.section-intro h2,
#about h2,
.highlight-card h3 {
  font-size: calc(var(--user-font-size) * 2);
}
.section-intro .section-subtitle {
  font-size: calc(var(--user-font-size) * 1.05);
}
.section-intro .section-desc,
.skills-card p,
.project-preview-card figcaption,
.jobs-card ol {
  font-size: calc(var(--user-font-size) * 0.9);
}
.skills-card h3 {
  font-size: calc(var(--user-font-size) * 1.25);
}
.experience-group-title {
  font-size: calc(var(--user-font-size) * 1.3);
}
.jobs-card .job-title,
.online-learning h3,
.edu-card h3 {
  font-size: calc(var(--user-font-size) * 1.2);
}
.jobs-card > p,
.edu-card h4,
.edu-card p {
  font-size: calc(var(--user-font-size) * 0.95);
}
.keyword span,
.card-date,
.impact-label {
  font-size: calc(var(--user-font-size) * 0.8);
}

@media (max-width: 48rem) {
  #home {
    min-height: auto;
    padding: 3.5rem 1.25rem 4rem;
    gap: 2.5rem;
  }

  #home img {
    width: 12rem;
    height: 12rem;
    outline-width: 0.35rem;
    outline-offset: 0.4rem;
    box-shadow:
      0 0 0 0.75rem var(--bg-card),
      0 0 0 0.95rem var(--bg-border),
      0 0.75rem 2rem var(--shadow-dark),
      0 0 1.5rem var(--accent-glow);
  }

  .home-content h1 {
    font-size: clamp(2rem, calc(var(--user-font-size) * 2.25), 2.75rem);
    line-height: 1.1;
  }

  .home-content h2 {
    font-size: clamp(1.25rem, calc(var(--user-font-size) * 1.5), 2rem);
  }

  .home-content p {
    font-size: clamp(1rem, calc(var(--user-font-size) * 1.05), 1.2rem);
  }
}

/* REDUCED MOTION: keep this last so motion overrides win */
@media (prefers-reduced-motion: reduce) {
  *:not(.ripple-effect),
  *:not(.ripple-effect)::before,
  *:not(.ripple-effect)::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }

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

/* =====================
   CHESS POPUP MODAL
   ===================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: hsla(0, 0%, 0%, 0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
}

.modal-overlay[hidden] {
  display: none;
}

.modal-surface {
  position: relative;
  background: var(--bg-card);
  color: var(--text-primary);
  border: 0.063rem solid var(--bg-border);
  box-shadow: var(--shadow);
}

.modal-box {
  border-radius: 0.75rem;
  padding: 2rem 2.5rem;
  width: 100%;
  max-width: min(88.32rem, 46rem);
  max-height: 49.05rem;
  overflow: auto;
}

.modal-close {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  width: 2rem;
  height: 2rem;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--text-primary);
  font-size: 1.4rem;
  line-height: 1;
  cursor: pointer;
}

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