/* ============================================================
   Marius Costache — personal site
   Dark, modern, single page.
   ============================================================ */

:root {
  /* Palette */
  --bg: #0a0a0f;
  --bg-elevated: #101018;
  --bg-card: rgba(255, 255, 255, 0.035);
  --border: rgba(255, 255, 255, 0.09);
  --border-strong: rgba(255, 255, 255, 0.16);

  --text: #ececf3;
  --text-muted: #a6a6b8;
  --text-faint: #6f6f83;

  --accent-1: #6366f1; /* indigo */
  --accent-2: #22d3ee; /* cyan */
  --accent-grad: linear-gradient(120deg, var(--accent-1), var(--accent-2));

  /* Type */
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Helvetica, Arial, sans-serif;
  --font-display: "Space Grotesk", "Inter", -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, Helvetica, Arial, sans-serif;

  /* Layout */
  --container: 1080px;
  --radius: 16px;
  --radius-sm: 10px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}

body {
  font-family: var(--font-body);
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text);
  background-color: var(--bg);
  background-image: radial-gradient(
      1200px 600px at 80% -10%,
      rgba(99, 102, 241, 0.12),
      transparent 60%
    ),
    radial-gradient(900px 500px at 0% 30%, rgba(34, 211, 238, 0.06), transparent 55%);
  background-repeat: no-repeat;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

::selection {
  background: rgba(99, 102, 241, 0.45);
  color: #fff;
}

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

a {
  color: var(--accent-2);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.container {
  width: min(var(--container), 100% - 3rem);
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 100;
  padding: 0.75rem 1.25rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: 0 0 var(--radius-sm) 0;
  color: var(--text);
}

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

/* ------------------------------------------------------------
   Header / nav
   ------------------------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 10, 15, 0.72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text);
  font-weight: 600;
}

.brand:hover {
  text-decoration: none;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  background: var(--accent-grad);
  color: #fff;
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1rem;
  letter-spacing: 0.01em;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 1.75rem;
}

.nav-links a {
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.18s ease;
}

.nav-links a:hover {
  color: var(--text);
  text-decoration: none;
}

/* ------------------------------------------------------------
   Hero
   ------------------------------------------------------------ */
.hero {
  position: relative;
  padding: clamp(5.5rem, 14vh, 9rem) 0 clamp(4rem, 9vh, 6rem);
  overflow: hidden;
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image: linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 0%, #000 20%, transparent 75%);
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  top: -220px;
  left: 50%;
  transform: translateX(-50%);
  width: 720px;
  height: 480px;
  background: radial-gradient(closest-side, rgba(99, 102, 241, 0.28), transparent);
  filter: blur(60px);
  pointer-events: none;
}

.hero-inner {
  position: relative;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  margin-bottom: 1.4rem;
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 34px;
  height: 1.5px;
  background: var(--accent-grad);
  border-radius: 2px;
}

.hero-title {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.06;
  letter-spacing: -0.03em;
  font-size: clamp(2.5rem, 6.4vw, 4.6rem);
  margin-bottom: 1.5rem;
}

.gradient-text {
  background: var(--accent-grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 46rem;
  color: var(--text-muted);
  font-size: clamp(1.05rem, 1.8vw, 1.2rem);
  margin-bottom: 2.25rem;
}

.hero-sub strong {
  color: var(--text);
  font-weight: 600;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-bottom: 3.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1.6rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.98rem;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease,
    border-color 0.18s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-2px);
}

.btn-primary {
  background: var(--accent-grad);
  color: #fff;
  box-shadow: 0 8px 28px rgba(99, 102, 241, 0.35);
}

.btn-primary:hover {
  box-shadow: 0 12px 34px rgba(99, 102, 241, 0.5);
}

.btn-ghost {
  border: 1px solid var(--border-strong);
  color: var(--text);
  background: rgba(255, 255, 255, 0.03);
}

.btn-ghost:hover {
  border-color: rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.06);
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  max-width: 46rem;
}

.stat {
  padding: 1.1rem 1.25rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-card);
}

.stat dt {
  font-family: var(--font-display);
  font-size: 1.9rem;
  font-weight: 700;
  line-height: 1.1;
  background: var(--accent-grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.stat dd {
  margin-top: 0.3rem;
  color: var(--text-faint);
  font-size: 0.82rem;
  line-height: 1.45;
}

/* ------------------------------------------------------------
   Sections (shared)
   ------------------------------------------------------------ */
.section {
  padding: clamp(4rem, 9vh, 6.5rem) 0;
  border-top: 1px solid var(--border);
}

.section-heading {
  margin-bottom: 2.75rem;
}

.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--accent-2);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 0.85rem;
}

.section-kicker::before {
  content: "";
  width: 26px;
  height: 1.5px;
  background: var(--accent-grad);
  border-radius: 2px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4vw, 2.7rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.section-sub {
  margin-top: 0.9rem;
  color: var(--text-muted);
  max-width: 36rem;
}

/* ------------------------------------------------------------
   About
   ------------------------------------------------------------ */
.prose {
  max-width: 44rem;
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 2.5rem;
}

.prose strong {
  color: var(--text);
  font-weight: 600;
}

.cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 2.5rem;
}

.card {
  padding: 1.75rem 1.85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.card:hover {
  border-color: rgba(99, 102, 241, 0.45);
  transform: translateY(-3px);
}

.card h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
  color: var(--text);
}

.card p {
  color: var(--text-muted);
  font-size: 0.98rem;
}

.card strong {
  color: var(--text);
  font-weight: 600;
}

.skills-grid {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 2.75rem;
}

.skill-block {
  padding: 1.75rem 1.85rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-elevated);
}

.skill-block h3 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 1.1rem;
  color: var(--text);
}

.tag-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.tag-list li {
  padding: 0.32rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
  color: var(--text-muted);
  font-size: 0.85rem;
  transition: border-color 0.18s ease, color 0.18s ease;
}

.tag-list li:hover {
  border-color: rgba(34, 211, 238, 0.5);
  color: var(--text);
}

.quote {
  position: relative;
  max-width: 44rem;
  padding: 1.6rem 1.8rem 1.6rem 2.2rem;
  border-left: 3px solid;
  border-image: linear-gradient(180deg, var(--accent-1), var(--accent-2)) 1;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  background: var(--bg-card);
}

.quote p {
  font-family: var(--font-display);
  font-size: 1.25rem;
  line-height: 1.55;
  color: var(--text);
  font-weight: 500;
}

.quote cite {
  display: block;
  margin-top: 0.9rem;
  color: var(--text-faint);
  font-size: 0.9rem;
  font-style: normal;
}

/* ------------------------------------------------------------
   Contact
   ------------------------------------------------------------ */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  max-width: 46rem;
}

.contact-card {
  position: relative;
  display: flex;
  align-items: center;
  gap: 1.1rem;
  padding: 1.6rem 1.7rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-card);
  color: var(--text);
  transition: border-color 0.2s ease, transform 0.2s ease, background 0.2s ease;
}

a.contact-card:hover {
  border-color: rgba(34, 211, 238, 0.55);
  background: rgba(34, 211, 238, 0.05);
  text-decoration: none;
  transform: translateY(-3px);
}

.contact-icon {
  display: inline-grid;
  place-items: center;
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--accent-grad);
  color: #fff;
  box-shadow: 0 6px 18px rgba(99, 102, 241, 0.35);
}

.contact-body {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  min-width: 0;
}

.contact-label {
  font-size: 0.82rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-faint);
  font-weight: 600;
}

.contact-value {
  font-size: 1.02rem;
  font-weight: 500;
  color: var(--text);
  overflow-wrap: anywhere;
}

.contact-link {
  color: var(--text);
  text-decoration: none;
  transition: color 0.18s ease;
}

.contact-link:hover {
  color: var(--accent-2);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.contact-arrow {
  margin-left: auto;
  color: var(--text-faint);
  font-size: 1.15rem;
  transition: color 0.18s ease, transform 0.18s ease;
}

a.contact-card:hover .contact-arrow {
  color: var(--accent-2);
  transform: translate(2px, -2px);
}

.copy-btn {
  margin-left: auto;
  flex-shrink: 0;
  padding: 0.45rem 0.95rem;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-muted);
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: border-color 0.18s ease, color 0.18s ease, background 0.18s ease;
}

.copy-btn:hover {
  border-color: rgba(34, 211, 238, 0.55);
  color: var(--text);
}

.copy-btn.copied {
  border-color: rgba(52, 211, 153, 0.6);
  color: #34d399;
}

/* ------------------------------------------------------------
   Footer
   ------------------------------------------------------------ */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2.25rem 0;
  color: var(--text-faint);
  font-size: 0.9rem;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.footer-inner a {
  color: var(--text-muted);
}

.footer-inner a:hover {
  color: var(--text);
  text-decoration: none;
}

/* ------------------------------------------------------------
   Scroll reveal
   ------------------------------------------------------------ */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

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

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

  .btn,
  .card,
  .contact-card,
  .tag-list li {
    transition: none;
  }
}

/* ------------------------------------------------------------
   Responsive
   ------------------------------------------------------------ */
@media (max-width: 820px) {
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 560px) {
  .brand-name {
    display: none;
  }

  .nav-links {
    gap: 1.1rem;
  }

  .hero-sub {
    font-size: 1rem;
  }

  .stat dt {
    font-size: 1.6rem;
  }

  .contact-value {
    font-size: 0.95rem;
  }
}