/* 2026-style clean portfolio — Kerolos Essa (no frameworks) */

:root {
  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;

  /* Dark Mode variables (required names) */
  --bg-primary: #0b0b0b;
  --bg-secondary: #161616;
  --text-color: #e5e7eb;
  --accent-color: #22c55e;
  --hover-accent: #7c3aed;

  /* Aliases used throughout the site (mapped to required vars) */
  --bg0: var(--bg-primary);
  --bg1: var(--bg-primary);
  --bg2: var(--bg-primary);
  --panel: var(--bg-secondary);

  --text: var(--text-color);
  --muted: rgba(229, 231, 235, 0.74);
  --muted2: rgba(229, 231, 235, 0.6);

  --accent: var(--accent-color);
  --accent2: var(--hover-accent);
  --good: var(--accent-color);
  --bad: #fb7185;

  --card: rgba(22, 22, 22, 0.86);
  --card2: rgba(22, 22, 22, 0.92);
  --stroke: rgba(229, 231, 235, 0.1);
  --stroke2: rgba(124, 58, 237, 0.55);

  --shadow: 0 18px 55px rgba(0, 0, 0, 0.42);
  --shadow2: 0 12px 34px rgba(0, 0, 0, 0.38);

  --radius: 18px;
  --radius2: 14px;
  --container: 1160px;

  --ease: cubic-bezier(0.2, 0.9, 0.2, 1);
  --t: 220ms;
  --t2: 380ms;
}

/* Light Mode variables (required selector + names) */
body.light-mode {
  --bg-primary: #ffffff;
  --bg-secondary: #f5f5f5;
  --text-color: #0b0b0b;
  --accent-color: #22c55e;
  --hover-accent: #7c3aed;

  --bg0: var(--bg-primary);
  --bg1: var(--bg-primary);
  --bg2: var(--bg-primary);
  --panel: var(--bg-secondary);

  --text: var(--text-color);
  --muted: rgba(11, 11, 11, 0.72);
  --muted2: rgba(11, 11, 11, 0.6);

  --accent: var(--accent-color);
  --accent2: var(--hover-accent);

  --card: rgba(245, 245, 245, 0.86);
  --card2: rgba(245, 245, 245, 0.92);
  --stroke: rgba(11, 11, 11, 0.12);
  --stroke2: rgba(124, 58, 237, 0.55);

  --shadow: 0 18px 55px rgba(0, 0, 0, 0.12);
  --shadow2: 0 12px 34px rgba(0, 0, 0, 0.1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: radial-gradient(1200px 700px at 20% 10%, rgba(34, 197, 94, 0.12), transparent 60%),
    radial-gradient(1100px 700px at 85% 0%, rgba(124, 58, 237, 0.14), transparent 55%),
    radial-gradient(900px 600px at 70% 85%, rgba(124, 58, 237, 0.1), transparent 55%),
    linear-gradient(180deg, var(--bg0), var(--bg1) 40%, var(--bg2));
  overflow-x: hidden;
}

/* Subtle noise + grid sheen */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(to bottom, rgba(255, 255, 255, 0.05), transparent 30%),
    repeating-linear-gradient(90deg,
      rgba(255, 255, 255, 0.03) 0,
      rgba(255, 255, 255, 0.03) 1px,
      transparent 1px,
      transparent 34px);
  mix-blend-mode: overlay;
  opacity: 0.25;
}

/* Stronger gradient drift overlay (modern 2026 feel) */
body::after {
  content: "";
  position: fixed;
  inset: -20%;
  pointer-events: none;
  background: radial-gradient(900px 480px at 15% 20%, rgba(34, 197, 94, 0.12), transparent 60%),
    radial-gradient(900px 480px at 85% 10%, rgba(124, 58, 237, 0.13), transparent 62%),
    radial-gradient(800px 520px at 70% 85%, rgba(34, 197, 94, 0.08), transparent 58%);
  filter: blur(18px);
  opacity: 0.9;
  animation: drift 14s var(--ease) infinite;
}

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

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

.container {
  width: min(var(--container), calc(100% - 2rem));
  margin-inline: auto;
}

.section {
  padding: clamp(64px, 7vw, 110px) 0;
  position: relative;
}

.section__head {
  display: grid;
  gap: 10px;
  margin-bottom: 26px;
}

.section__title {
  margin: 0;
  font-size: clamp(26px, 3vw, 36px);
  letter-spacing: -0.03em;
}

.section__subtitle {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.skip-link {
  position: absolute;
  top: 10px;
  left: 10px;
  padding: 10px 12px;
  background: var(--card2);
  border: 1px solid var(--stroke);
  border-radius: 10px;
  transform: translateY(-160%);
  transition: transform var(--t) var(--ease);
  z-index: 9999;
}

.skip-link:focus {
  transform: translateY(0);
  outline: none;
}

/* Header */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(11, 11, 11, 0.72);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(229, 231, 235, 0.12);
}

body.light-mode .header {
  background: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid rgba(11, 11, 11, 0.1);
}

.header__inner {
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 14px;
  padding: 14px 0;
}

.header.is-compact .header__inner {
  padding: 10px 0;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
}

.logo__mark {
  width: 12px;
  height: 12px;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--accent), var(--accent2));
  box-shadow: 0 0 0 5px rgba(34, 197, 94, 0.12), 0 0 28px rgba(34, 197, 94, 0.22);
}

.nav {
  display: flex;
  align-items: center;
  gap: 18px;
}

.nav__link {
  position: relative;
  font-size: 14px;
  color: var(--muted);
  padding: 10px 10px;
  border-radius: 12px;
  transition: transform var(--t) var(--ease), background var(--t) var(--ease), color var(--t) var(--ease),
    box-shadow var(--t) var(--ease), border-color var(--t) var(--ease);
  border: 1px solid transparent;
}

.nav__link:hover {
  background: rgba(22, 22, 22, 0.9);
  color: var(--text);
  transform: translateY(-1px);
  border-color: rgba(124, 58, 237, 0.5);
  box-shadow: 0 0 0 4px rgba(124, 58, 237, 0.12);
}

.nav__link.is-active {
  color: var(--text);
  background: linear-gradient(180deg, rgba(34, 197, 94, 0.14), rgba(124, 58, 237, 0.1));
  border: 1px solid rgba(229, 231, 235, 0.14);
}

.header__actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
}

.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: var(--card);
  color: var(--text);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset;
  cursor: pointer;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.icon-btn:hover {
  transform: translateY(-1px);
  border-color: var(--stroke2);
  background: var(--card2);
}

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

.icon {
  width: 18px;
  height: 18px;
  fill: currentColor;
}

.nav__toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: var(--card);
  cursor: pointer;
  transition: transform var(--t) var(--ease), background var(--t) var(--ease);
}

.nav__toggle:hover {
  transform: translateY(-1px);
  background: var(--card2);
}

.nav__toggle-line {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  margin: 4px auto;
  border-radius: 2px;
}

.progress {
  height: 2px;
  width: 100%;
  background: transparent;
}

.progress__bar {
  height: 100%;
  width: 0%;
  background: var(--accent);
  box-shadow: 0 0 18px rgba(34, 197, 94, 0.35);
}

/* Hero */
.hero {
  padding-top: clamp(70px, 8vw, 120px);
  overflow: clip;
}

.hero__bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 0;
}

.hero__bg-gradient {
  position: absolute;
  inset: -40%;
  background: radial-gradient(700px 420px at 20% 20%, rgba(56, 189, 248, 0.16), transparent 60%),
    radial-gradient(700px 420px at 80% 35%, rgba(99, 102, 241, 0.18), transparent 60%),
    radial-gradient(650px 380px at 60% 85%, rgba(56, 189, 248, 0.12), transparent 58%);
  filter: blur(10px);
  opacity: 0.85;
  animation: heroGlow 10s var(--ease) infinite;
}

.hero__bg-code {
  position: absolute;
  inset: 0;
  overflow: hidden;
  opacity: 0.75;
}

.code-float {
  position: absolute;
  left: var(--x, 50%);
  top: var(--y, 50%);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: var(--s, 14px);
  color: rgba(248, 250, 252, 0.45);
  text-shadow: 0 0 18px rgba(56, 189, 248, 0.25);
  transform: translate3d(-50%, -50%, 0);
  animation: codeRise var(--d, 10s) linear infinite;
  will-change: transform, opacity;
  user-select: none;
}

body.light-mode .code-float {
  color: rgba(11, 11, 11, 0.42);
  text-shadow: 0 0 18px rgba(124, 58, 237, 0.18);
}

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

.hero__grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: clamp(22px, 4vw, 52px);
  align-items: center;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--muted);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.hero__title {
  margin: 0;
  letter-spacing: -0.05em;
  line-height: 1.05;
  font-size: clamp(34px, 4.5vw, 60px);
}

.hero__name {
  display: block;
  background: linear-gradient(120deg, rgba(255, 255, 255, 0.98), rgba(255, 255, 255, 0.74));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__role {
  display: block;
  margin-top: 10px;
  font-size: clamp(16px, 2.2vw, 22px);
  font-weight: 700;
  background: linear-gradient(90deg, var(--accent), var(--accent2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero__desc {
  margin: 18px 0 0;
  color: var(--muted);
  line-height: 1.8;
  max-width: 58ch;
}

.hero__cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.hero__stats {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.stat {
  padding: 14px 14px;
  border-radius: var(--radius2);
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg, var(--card2), var(--card));
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset;
}

.stat__value {
  font-weight: 800;
  letter-spacing: -0.02em;
}

.stat__label {
  margin-top: 4px;
  font-size: 13px;
  color: var(--muted2);
}

/* Avatar */
.hero__visual {
  justify-self: end;
  position: relative;
  min-height: 420px;
  display: grid;
  place-items: center;
}

.avatar {
  width: min(360px, 88vw);
  aspect-ratio: 1;
  position: relative;
  display: grid;
  place-items: center;
  filter: drop-shadow(0 30px 80px rgba(0, 0, 0, 0.45));
}

.avatar__ring {
  position: absolute;
  inset: 0;
  border-radius: 999px;
  background: conic-gradient(from 90deg, var(--accent), var(--accent2), var(--accent), rgba(255, 255, 255, 0.25));
  filter: blur(0.2px);
  opacity: 0.9;
  animation: spin 10s linear infinite;
}

.avatar__core {
  position: relative;
  width: 86%;
  height: 86%;
  border-radius: 999px;
  background:
    radial-gradient(120px 120px at 25% 25%, rgba(56, 189, 248, 0.25), transparent 55%),
    radial-gradient(160px 160px at 70% 30%, rgba(99, 102, 241, 0.22), transparent 60%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.04));
  border: 1px solid rgba(255, 255, 255, 0.18);
  backdrop-filter: blur(14px);
  display: grid;
  place-items: center;
  animation: float 5.5s var(--ease) infinite;
}

.avatar__initials {
  font-size: clamp(34px, 4vw, 48px);
  font-weight: 900;
  letter-spacing: -0.06em;
  color: rgba(255, 255, 255, 0.92);
  text-shadow: 0 12px 40px rgba(0, 0, 0, 0.35);
}

body.light-mode .avatar__initials {
  color: rgba(11, 11, 11, 0.9);
}

/* Photo avatar */
.avatar__core--photo {
  background: none;
  border: none;
  overflow: hidden;
}

.avatar__photo {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center top;
  border-radius: 999px;
  display: block;
}

.avatar__glow {
  position: absolute;
  inset: -16%;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 30%, rgba(56, 189, 248, 0.18), transparent 55%),
    radial-gradient(circle at 70% 20%, rgba(99, 102, 241, 0.16), transparent 55%);
  filter: blur(18px);
  opacity: 0.9;
  animation: pulse 3.8s var(--ease) infinite;
}

.hero__chips {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.chip {
  position: absolute;
  padding: 10px 12px;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.06);
  color: var(--muted);
  font-size: 13px;
  backdrop-filter: blur(12px);
  animation: float2 7.2s var(--ease) infinite;
}

.chip:nth-child(1) {
  top: 16%;
  left: -2%;
}

.chip:nth-child(2) {
  top: 10%;
  right: -2%;
  animation-delay: -1.4s;
}

.chip:nth-child(3) {
  bottom: 18%;
  left: 4%;
  animation-delay: -2.4s;
}

.chip:nth-child(4) {
  bottom: 10%;
  right: 0%;
  animation-delay: -3.1s;
}

/* Cards / UI */
.card {
  border-radius: var(--radius);
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg, var(--card2), var(--card));
  box-shadow: var(--shadow2);
}

.card--soft {
  box-shadow: none;
}

.lead {
  margin: 0;
  line-height: 1.9;
  color: var(--muted);
}

.about__grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 16px;
  align-items: start;
}

.about__cards {
  display: grid;
  gap: 12px;
}

.mini-card {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 12px;
  align-items: center;
  padding: 14px;
  border-radius: var(--radius2);
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 86%, transparent);
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
}

.mini-card:hover {
  transform: translateY(-2px);
  border-color: var(--stroke2);
  background: color-mix(in srgb, var(--bg-secondary) 92%, transparent);
}

.mini-card__icon {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: linear-gradient(180deg, rgba(56, 189, 248, 0.16), rgba(99, 102, 241, 0.14));
  border: 1px solid rgba(255, 255, 255, 0.12);
}

.mini-card__label {
  font-size: 12px;
  color: var(--muted2);
}

.mini-card__value {
  font-weight: 800;
  letter-spacing: -0.02em;
}

/* Stack */
.stack {
  display: grid;
  gap: 18px;
}

.stack__group {
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 72%, transparent);
  border-radius: var(--radius);
  padding: 18px;
}

.stack__title {
  margin: 0 0 12px;
  font-size: 16px;
  letter-spacing: -0.02em;
}

.stack__grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.tag-card {
  padding: 14px 14px;
  border-radius: var(--radius2);
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg,
      color-mix(in srgb, var(--bg-secondary) 92%, transparent),
      color-mix(in srgb, var(--bg-secondary) 78%, transparent));
  display: flex;
  align-items: center;
  gap: 10px;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset;
}

.tag-card:hover {
  transform: translateY(-3px);
  border-color: rgba(56, 189, 248, 0.35);
  box-shadow: 0 14px 44px rgba(0, 0, 0, 0.32);
}

.tag-card__icon {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-weight: 900;
  letter-spacing: -0.05em;
  background: radial-gradient(circle at 30% 30%, rgba(56, 189, 248, 0.28), rgba(99, 102, 241, 0.18));
  border: 1px solid rgba(255, 255, 255, 0.14);
}

.tag-card__name {
  font-weight: 800;
  font-size: 14px;
}

/* Grids */
.grid {
  display: grid;
  gap: 14px;
}

.grid--skills {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid--projects {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid--services {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.skill-card,
.service-card {
  border-radius: var(--radius);
  border: 1px solid var(--stroke);
  background: linear-gradient(180deg,
      color-mix(in srgb, var(--bg-secondary) 92%, transparent),
      color-mix(in srgb, var(--bg-secondary) 78%, transparent));
  padding: 18px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}

.skill-card:hover,
.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(56, 189, 248, 0.35);
  box-shadow: 0 18px 55px rgba(0, 0, 0, 0.38);
}

.skill-card:hover .skill-card__icon {
  transform: rotate(-6deg) scale(1.06);
  border-color: rgba(56, 189, 248, 0.35);
  box-shadow: 0 0 0 4px rgba(56, 189, 248, 0.12), 0 0 32px rgba(56, 189, 248, 0.18);
}

.skill-card__top {
  display: flex;
  align-items: center;
  gap: 10px;
}

.skill-card__icon {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--stroke);
  font-size: 16px;
  transition: transform var(--t) var(--ease), box-shadow var(--t2) var(--ease), border-color var(--t) var(--ease);
}

.skill-card__title,
.service-card__title {
  margin: 0;
  font-size: 16px;
  letter-spacing: -0.02em;
}

.skill-card__desc,
.service-card__desc {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.7;
}

.service-card__icon {
  width: 50px;
  height: 50px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  background: linear-gradient(180deg, rgba(56, 189, 248, 0.16), rgba(99, 102, 241, 0.14));
  border: 1px solid rgba(255, 255, 255, 0.12);
  margin-bottom: 12px;
}

/* Projects */
.project-card {
  border-radius: var(--radius);
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 78%, transparent);
  overflow: hidden;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06) inset;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
  position: relative;
}

.project-card::before {
  content: "";
  position: absolute;
  inset: -1px;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.0), rgba(56, 189, 248, 0.35), rgba(99, 102, 241, 0.35), rgba(99, 102, 241, 0.0));
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--t2) var(--ease);
  pointer-events: none;
}

.project-card:hover {
  transform: translateY(-5px);
  border-color: rgba(99, 102, 241, 0.35);
  box-shadow: var(--shadow);
}

.project-card:hover::before {
  opacity: 1;
}

.project-card__media {
  position: relative;
  aspect-ratio: 16 / 9;
  background: color-mix(in srgb, var(--bg-secondary) 86%, transparent);
  overflow: hidden;
}

.project-card__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.02);
  transition: transform 700ms var(--ease), filter 700ms var(--ease);
  filter: saturate(1.05) contrast(1.02);
}

.project-card:hover .project-card__img {
  transform: scale(1.08);
  filter: saturate(1.15) contrast(1.05);
}

.project-card__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(700px 260px at 20% 0%, rgba(56, 189, 248, 0.14), transparent 60%),
    radial-gradient(700px 260px at 80% 100%, rgba(99, 102, 241, 0.16), transparent 60%);
  opacity: 0.8;
  transition: opacity var(--t2) var(--ease);
  pointer-events: none;
}

.project-card:hover .project-card__media::after {
  opacity: 1;
}

.project-card__body {
  padding: 16px 16px 18px;
}

.project-card__title {
  margin: 0;
  font-size: 16px;
  letter-spacing: -0.02em;
}

.project-card__desc {
  margin: 10px 0 0;
  color: var(--muted);
  line-height: 1.7;
}

.project-card__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.pill {
  font-size: 12px;
  color: var(--muted);
  padding: 8px 10px;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 82%, transparent);
}

.project-card__actions {
  display: flex;
  gap: 10px;
  margin-top: 14px;
}

/* Buttons */
.btn {
  --btn-bg: rgba(255, 255, 255, 0.08);
  --btn-bd: var(--stroke);
  --btn-tx: var(--text);
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-radius: 14px;
  padding: 12px 14px;
  border: 1px solid var(--btn-bd);
  background: var(--btn-bg);
  color: var(--btn-tx);
  font-weight: 800;
  letter-spacing: -0.02em;
  cursor: pointer;
  user-select: none;
  transition: transform var(--t) var(--ease), filter var(--t) var(--ease), border-color var(--t) var(--ease),
    background var(--t) var(--ease);
  overflow: hidden;
  will-change: transform;
}

.btn:hover {
  transform: translateY(-2px);
  border-color: var(--stroke2);
}

.btn:focus-visible {
  outline: none;
  box-shadow: 0 0 0 4px rgba(34, 197, 94, 0.18), 0 0 0 1px rgba(34, 197, 94, 0.5) inset;
}

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

.btn[aria-disabled="true"] {
  opacity: 0.55;
  pointer-events: none;
}

.btn--primary {
  --btn-bg: var(--accent-color);
  --btn-bd: rgba(34, 197, 94, 0.55);
  --btn-tx: #0b0b0b;
}

body.light-mode .btn--primary {
  --btn-tx: #0b0b0b;
}

.btn--ghost {
  --btn-bg: color-mix(in srgb, var(--bg-secondary) 86%, transparent);
}

.btn--glass {
  --btn-bg: color-mix(in srgb, var(--bg-secondary) 82%, transparent);
  box-shadow: 0 16px 44px rgba(0, 0, 0, 0.24);
}

.btn--primary:hover {
  filter: brightness(1.02);
  border-color: rgba(124, 58, 237, 0.55);
  box-shadow: 0 0 0 5px rgba(34, 197, 94, 0.14), 0 18px 55px rgba(0, 0, 0, 0.28);
}

.btn--ghost:hover,
.btn--glass:hover {
  box-shadow: 0 0 0 5px rgba(124, 58, 237, 0.12);
}

.btn--sm {
  padding: 10px 12px;
  font-size: 13px;
  border-radius: 12px;
}

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

/* Ripple (JS sets CSS vars) */
[data-ripple]::after {
  content: "";
  position: absolute;
  left: var(--rx, 50%);
  top: var(--ry, 50%);
  width: 6px;
  height: 6px;
  border-radius: 999px;
  transform: translate(-50%, -50%) scale(0);
  background: radial-gradient(circle, rgba(255, 255, 255, 0.55), rgba(255, 255, 255, 0) 60%);
  opacity: 0;
  pointer-events: none;
}

[data-ripple].is-rippling::after {
  opacity: 1;
  animation: ripple 700ms var(--ease) forwards;
}

/* Contact */
.contact {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 16px;
  align-items: start;
}

.contact__form {
  padding: 18px;
}

.field {
  display: grid;
  gap: 8px;
  margin-bottom: 14px;
}

.field__label {
  font-size: 13px;
  color: var(--muted);
  font-weight: 700;
}

.field__input {
  width: 100%;
  padding: 12px 12px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 86%, transparent);
  color: var(--text);
  outline: none;
  transition: border-color var(--t) var(--ease), background var(--t) var(--ease), transform var(--t) var(--ease);
}

.field__input::placeholder {
  color: rgba(255, 255, 255, 0.45);
}

body.light-mode .field__input::placeholder {
  color: rgba(11, 11, 11, 0.5);
}

.field__input:focus {
  border-color: color-mix(in srgb, var(--accent-color) 60%, transparent);
  background: color-mix(in srgb, var(--bg-secondary) 92%, transparent);
  transform: translateY(-1px);
}

.field__textarea {
  resize: vertical;
  min-height: 130px;
}

.field__error {
  min-height: 16px;
  color: var(--bad);
  font-size: 12px;
}

.field.is-invalid .field__input {
  border-color: rgba(251, 113, 133, 0.6);
}

.form-note {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 13px;
}

.info-card {
  padding: 18px;
}

.info-card__title {
  margin: 0 0 10px;
  letter-spacing: -0.02em;
}

.info-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.info-list__item {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 12px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 82%, transparent);
}

.info-list__label {
  color: var(--muted2);
  font-size: 13px;
}

.info-list__value a {
  color: var(--text);
  text-decoration: underline;
  text-decoration-color: rgba(56, 189, 248, 0.35);
  text-underline-offset: 3px;
}

.social {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-top: 14px;
}

.social--4 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.social__link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 12px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 86%, transparent);
  color: var(--text);
  font-weight: 800;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
  overflow: hidden;
  position: relative;
}

.social__link:hover {
  transform: translateY(-2px);
  border-color: var(--hover-accent);
  background: color-mix(in srgb, var(--bg-secondary) 92%, transparent);
}

.social__icon {
  width: 30px;
  height: 30px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.18), rgba(99, 102, 241, 0.16));
  border: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 12px;
  transition: transform var(--t) var(--ease), box-shadow var(--t2) var(--ease);
}

.social__link:hover .social__icon {
  transform: translateY(-1px) rotate(-4deg);
  box-shadow: 0 0 0 4px rgba(56, 189, 248, 0.12), 0 0 36px rgba(56, 189, 248, 0.2);
}

/* Footer */
.footer {
  padding: 28px 0 48px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(0, 0, 0, 0.1);
}

body.light-mode .footer {
  border-top: 1px solid rgba(11, 11, 11, 0.08);
  background: rgba(245, 245, 245, 0.7);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.footer__role {
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.footer__name {
  font-weight: 900;
  letter-spacing: -0.03em;
}

.footer__copy {
  color: var(--muted);
  margin-top: 6px;
  font-size: 13px;
}

.footer__right {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.footer__social {
  display: inline-flex;
  gap: 10px;
}

.footer__social-link {
  width: 42px;
  height: 42px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: var(--card);
  display: grid;
  place-items: center;
  transition: transform var(--t) var(--ease), border-color var(--t) var(--ease), background var(--t) var(--ease);
  position: relative;
  overflow: hidden;
}

.footer__social-link:hover {
  transform: translateY(-2px);
  border-color: rgba(56, 189, 248, 0.35);
  background: var(--card2);
  box-shadow: 0 0 0 4px rgba(56, 189, 248, 0.12), 0 18px 55px rgba(0, 0, 0, 0.28);
}

.footer__social-icon {
  font-weight: 900;
  letter-spacing: -0.06em;
  color: var(--text);
  opacity: 0.9;
  font-size: 12px;
}

.to-top {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--stroke);
  background: var(--card);
  color: var(--text);
  cursor: pointer;
  transition: transform var(--t) var(--ease), background var(--t) var(--ease), border-color var(--t) var(--ease);
  position: relative;
  overflow: hidden;
}

.to-top:hover {
  transform: translateY(-2px);
  background: var(--card2);
  border-color: rgba(56, 189, 248, 0.35);
}

.to-top__icon {
  width: 28px;
  height: 28px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.2), rgba(99, 102, 241, 0.16));
  border: 1px solid rgba(255, 255, 255, 0.12);
  font-weight: 900;
}

/* Floating back-to-top (FAB) */
.fab-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  width: 52px;
  height: 52px;
  border-radius: 18px;
  border: 1px solid var(--stroke);
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.18), rgba(99, 102, 241, 0.16));
  backdrop-filter: blur(12px);
  color: var(--text);
  display: grid;
  place-items: center;
  cursor: pointer;
  box-shadow: 0 18px 55px rgba(0, 0, 0, 0.35);
  opacity: 0;
  transform: translateY(12px) scale(0.96);
  pointer-events: none;
  transition: opacity var(--t2) var(--ease), transform var(--t2) var(--ease), border-color var(--t) var(--ease);
  z-index: 1200;
  overflow: hidden;
}

.fab-top.is-visible {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
}

.fab-top:hover {
  border-color: rgba(56, 189, 248, 0.45);
  box-shadow: 0 0 0 5px rgba(56, 189, 248, 0.12), 0 22px 70px rgba(0, 0, 0, 0.42);
}

.fab-top__icon {
  width: 34px;
  height: 34px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: rgba(248, 250, 252, 0.08);
  border: 1px solid rgba(248, 250, 252, 0.18);
  font-weight: 900;
}

/* Reveal on scroll */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 700ms var(--ease), transform 700ms var(--ease);
}

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

.reveal[data-delay] {
  transition-delay: var(--delay, 0ms);
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

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

  .avatar__ring,
  .avatar__core,
  .avatar__glow,
  .chip,
  body::after,
  .hero__bg-gradient,
  .code-float {
    animation: none !important;
  }
}

/* Responsive */
@media (max-width: 980px) {
  .hero__grid {
    grid-template-columns: 1fr;
  }

  .hero__visual {
    justify-self: center;
    min-height: 360px;
  }

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

  .stack__grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .grid--skills,
  .grid--projects,
  .grid--services {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .footer__inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 640px) {
  .header__inner {
    grid-template-columns: 1fr auto auto;
  }

  .nav__toggle {
    display: inline-grid;
    place-items: center;
  }

  .nav {
    position: fixed;
    left: 1rem;
    right: 1rem;
    top: 72px;
    display: grid;
    gap: 8px;
    padding: 12px;
    border-radius: 18px;
    border: 1px solid var(--stroke);
    background: rgba(10, 16, 32, 0.82);
    backdrop-filter: blur(16px);
    transform: translateY(-10px);
    opacity: 0;
    pointer-events: none;
    transition: transform var(--t2) var(--ease), opacity var(--t2) var(--ease);
  }

  body.light-mode .nav {
    background: rgba(245, 245, 245, 0.92);
  }

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

  .nav__link {
    padding: 12px 12px;
  }

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

  .grid--skills,
  .grid--projects,
  .grid--services {
    grid-template-columns: 1fr;
  }

  .project-card__actions {
    flex-direction: column;
  }
}

/* Keyframes */
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-10px);
  }
}

@keyframes float2 {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-6px);
  }
}

@keyframes pulse {

  0%,
  100% {
    transform: scale(1);
    opacity: 0.85;
  }

  50% {
    transform: scale(1.06);
    opacity: 1;
  }
}

@keyframes ripple {
  from {
    transform: translate(-50%, -50%) scale(0);
    opacity: 0.75;
  }

  to {
    transform: translate(-50%, -50%) scale(34);
    opacity: 0;
  }
}

@keyframes drift {

  0%,
  100% {
    transform: translate3d(0, 0, 0) scale(1);
  }

  50% {
    transform: translate3d(2.2%, -1.8%, 0) scale(1.03);
  }
}

@keyframes heroGlow {

  0%,
  100% {
    transform: translate3d(0, 0, 0) scale(1);
    opacity: 0.78;
  }

  50% {
    transform: translate3d(-1.6%, 1.2%, 0) scale(1.04);
    opacity: 0.9;
  }
}

@keyframes codeRise {
  0% {
    transform: translate3d(-50%, -40%, 0) translateY(34px);
    opacity: 0;
  }

  10% {
    opacity: 0.85;
  }

  85% {
    opacity: 0.55;
  }

  100% {
    transform: translate3d(-50%, -70%, 0) translateY(-240px);
    opacity: 0;
  }
}
/* skills bar */
.skills-bars {
  margin-top: 26px;
  display: grid;
  gap: 12px;
}
.skills-bars__item {
  border-radius: var(--radius2);
  border: 1px solid var(--stroke);
  background: color-mix(in srgb, var(--bg-secondary) 88%, transparent);
  padding: 10px 12px;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.05) inset;
}
.skills-bars__label-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
  font-size: 13px;
}
.skills-bars__label {
  color: var(--muted);
}
.skills-bars__value {
  font-weight: 700;
}
.skills-bars__track {
  width: 100%;
  height: 6px;
  border-radius: 999px;
  background: color-mix(in srgb, var(--bg-secondary) 70%, transparent);
  overflow: hidden;
}
.skills-bars__fill {
  height: 100%;
  width: 0%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--accent-color), var(--hover-accent));
  box-shadow: 0 0 18px rgba(34, 197, 94, 0.35);
  transition: width 900ms var(--ease);
}

/* GitHub Projects Loader */
.projects-loader {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 48px 0;
}

.loader-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--stroke);
  border-top-color: var(--accent);
  border-radius: 999px;
  animation: spinLoader 0.8s linear infinite;
}

.loader-text {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

@keyframes spinLoader {
  to {
    transform: rotate(360deg);
  }
}