/* =========================
   Base styles
   ========================= */

:root {
  --bg-color: #020b24;          /* dark blue */
  --heading-color: #a8ffbf;     /* pastel green */
  --text-color: #ffffff;        /* white */
  --muted-text: #d1d5db;
  --card-bg: #07132f;
  --border-soft: #1f2937;
  --max-width: 900px;
  --radius: 0.9rem;
  --shadow-soft: 0 14px 40px rgba(0, 0, 0, 0.6);
}

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

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
}

/* Accessibility: skip link */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: #111827;
  color: #f9fafb;
  padding: 0.5rem 1rem;
  border-radius: 0 0 0.5rem 0.5rem;
  z-index: 100;
}
.skip-link:focus {
  left: 0.75rem;
}

/* =========================
   Header / Navigation
   ========================= */

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(2, 11, 36, 0.95);
  border-bottom: 1px solid rgba(148, 163, 184, 0.3);
  backdrop-filter: blur(12px);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.5rem 1rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

/* simple circular mark instead of logo image */
.logo-mark {
  width: 32px;
  height: 32px;
  border-radius: 999px;
  background: radial-gradient(circle at 30% 30%, #a8ffbf, #1d4ed8);
  border: 2px solid #0b1120;
}

.main-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  font-size: 0.9rem;
}

.main-nav a {
  text-decoration: none;
  color: var(--muted-text);
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  border: 1px solid transparent;
}
.main-nav a:hover,
.main-nav a:focus {
  color: var(--text-color);
  border-color: rgba(168, 255, 191, 0.5);
  background: rgba(15, 23, 42, 0.9);
}

/* =========================
   Hero section
   ========================= */

.hero {
  padding: 3rem 1rem 2rem;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
  align-items: center;
  background: radial-gradient(circle at top left, rgba(168, 255, 191, 0.25), transparent 55%),
              radial-gradient(circle at bottom right, rgba(59, 130, 246, 0.25), transparent 55%),
              #020617;
  border-radius: 1.2rem;
  padding: 1.75rem;
  border: 1px solid rgba(148, 163, 184, 0.4);
  box-shadow: var(--shadow-soft);
}

.hero-image {
  border-radius: 999px;
  width: 200px;
  height: 200px;
  object-fit: cover;
  border: 3px solid var(--heading-color);
}

.hero-text-block {
  flex: 1;
  min-width: 220px;
}

.hero h1 {
  margin: 0 0 0.4rem;
  font-size: clamp(1.7rem, 2.7vw, 2.2rem);
  color: var(--heading-color);
}

.hero-title {
  margin: 0 0 0.5rem;
  font-size: 1rem;
  font-weight: 600;
}

.hero-sub {
  margin: 0;
  color: var(--muted-text);
  font-size: 0.95rem;
}

/* =========================
   Sections
   ========================= */

.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.8rem 1rem 0.8rem;
}

.section h2 {
  margin: 0 0 0.75rem;
  font-size: 1.25rem;
  color: var(--heading-color);
}

.section p {
  margin: 0 0 0.6rem;
}

/* Technical skills */

.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
  margin-top: 0.5rem;
}

.skill-group {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 1rem;
  border: 1px solid var(--border-soft);
}

.skill-group h3 {
  margin-top: 0;
  margin-bottom: 0.4rem;
  font-size: 1rem;
  color: var(--heading-color);
}

.skill-group ul {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.92rem;
}

.skill-group li {
  margin-bottom: 0.25rem;
}

/* Timeline (Education & Experience) */

.timeline {
  display: grid;
  gap: 1rem;
  margin-top: 0.5rem;
}

.timeline-item {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 1rem;
  border: 1px solid var(--border-soft);
}

.timeline-item h3 {
  margin: 0 0 0.3rem;
  font-size: 1rem;
  color: var(--heading-color);
}

.timeline-meta {
  margin: 0 0 0.5rem;
  font-size: 0.9rem;
  color: var(--muted-text);
}

/* Projects */

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px));
  gap: 1rem;
  margin-top: 0.5rem;
}

.project-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 1rem;
  border: 1px solid var(--border-soft);
}

.project-card h3 {
  margin-top: 0;
  margin-bottom: 0.4rem;
  font-size: 1rem;
  color: var(--heading-color);
}

.project-card p {
  margin: 0 0 0.4rem;
  font-size: 0.94rem;
}

.project-tags {
  font-size: 0.85rem;
  color: var(--muted-text);
}

/* Contact */

.contact-list {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 0;
  font-size: 0.95rem;
}

.contact-list li {
  margin-bottom: 0.3rem;
}

.contact-list a {
  color: var(--heading-color);
  text-decoration: none;
}
.contact-list a:hover,
.contact-list a:focus {
  text-decoration: underline;
}

/* =========================
   Footer
   ========================= */

.site-footer {
  max-width: var(--max-width);
  margin: 2rem auto 2.5rem;
  padding: 0 1rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--muted-text);
}

/* =========================
   Responsive tweaks
   ========================= */

@media (max-width: 650px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .main-nav {
    justify-content: flex-start;
  }
}