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

:root {
  --clr-bg:      #0f1117;
  --clr-surface: #181b23;
  --clr-border:  #282d3a;
  --clr-text:    #e2e4e9;
  --clr-muted:   #9ca3af;
  --clr-accent:  #6366f1;
  --clr-accent2: #818cf8;
  --clr-white:   #ffffff;
  --font:        'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--clr-bg);
  color: var(--clr-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--clr-accent2); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 960px; margin: 0 auto; padding: 0 1.5rem; }

/* ── Header ──────────────────────────────────────────────────────── */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(15,17,23,.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--clr-border);
  padding: .75rem 0;
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; }

.logo { display: flex; align-items: center; gap: .5rem; font-weight: 700; font-size: 1.1rem; color: var(--clr-white); }
.logo:hover { text-decoration: none; }
.logo-mark { color: var(--clr-accent); font-size: 1.25rem; }
.logo-accent { color: var(--clr-muted); font-weight: 400; }

.site-nav { display: flex; align-items: center; gap: 1.25rem; }
.site-nav a { color: var(--clr-muted); font-size: .9rem; font-weight: 500; }
.site-nav a:hover { color: var(--clr-white); text-decoration: none; }

/* ── Buttons ─────────────────────────────────────────────────────── */
.btn {
  display: inline-block; padding: .6rem 1.25rem; border-radius: 8px;
  font-weight: 600; font-size: .9rem; transition: all .2s;
}
.btn-primary { background: var(--clr-accent); color: var(--clr-white); }
.btn-primary:hover { background: var(--clr-accent2); text-decoration: none; }
.btn-white { background: var(--clr-white); color: var(--clr-bg); }
.btn-white:hover { opacity: .9; text-decoration: none; }

/* ── Hero ────────────────────────────────────────────────────────── */
.hero {
  padding: 5rem 0 4rem;
  text-align: center;
  background: linear-gradient(180deg, var(--clr-surface) 0%, var(--clr-bg) 100%);
}
.hero h1 { font-size: 3rem; font-weight: 800; letter-spacing: -.02em; margin: .5rem 0; }
.hero-badge {
  display: inline-block; padding: .3rem .8rem; border-radius: 999px;
  background: rgba(99,102,241,.15); color: var(--clr-accent2);
  font-size: .8rem; font-weight: 600; letter-spacing: .04em; text-transform: uppercase;
}
.hero-sub { max-width: 560px; margin: 1rem auto 0; color: var(--clr-muted); font-size: 1.1rem; }

/* ── Sections ────────────────────────────────────────────────────── */
.section { padding: 4rem 0; }
.section-alt { background: var(--clr-surface); }

.section-title {
  font-size: 1.6rem; font-weight: 700; margin-bottom: 1.5rem;
  position: relative; padding-bottom: .5rem;
}
.section-title::after {
  content: ''; position: absolute; bottom: 0; left: 0;
  width: 48px; height: 3px; border-radius: 2px; background: var(--clr-accent);
}

.section p { color: var(--clr-muted); max-width: 720px; line-height: 1.75; }

/* ── Skills grid ─────────────────────────────────────────────────── */
.skills-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px,1fr)); gap: 1.25rem; }
.skill-card {
  background: var(--clr-bg); border: 1px solid var(--clr-border); border-radius: 10px;
  padding: 1.25rem;
}
.skill-card h3 { font-size: 1rem; font-weight: 600; margin-bottom: .4rem; color: var(--clr-white); }
.skill-card p { font-size: .88rem; color: var(--clr-muted); }

/* ── Timeline ────────────────────────────────────────────────────── */
.timeline { display: flex; flex-direction: column; gap: 2rem; }
.timeline-item {
  border-left: 2px solid var(--clr-accent);
  padding-left: 1.5rem; position: relative;
}
.timeline-item::before {
  content: ''; position: absolute; left: -6px; top: 6px;
  width: 10px; height: 10px; border-radius: 50%; background: var(--clr-accent);
}
.timeline-header { margin-bottom: .5rem; }
.timeline-header h3 { font-size: 1.1rem; font-weight: 600; color: var(--clr-white); }
.timeline-meta { font-size: .85rem; color: var(--clr-muted); }
.timeline-item ul { list-style: disc; padding-left: 1.25rem; }
.timeline-item li { font-size: .92rem; color: var(--clr-muted); margin-bottom: .3rem; }

/* ── Certifications grid ─────────────────────────────────────────── */
.cert-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px,1fr)); gap: 1rem; }
.cert-card {
  background: var(--clr-bg); border: 1px solid var(--clr-border); border-radius: 10px;
  padding: 1rem 1.25rem; font-size: .92rem; font-weight: 500; color: var(--clr-white);
}

/* ── CTA Band ────────────────────────────────────────────────────── */
.section-cta-band {
  padding: 4rem 0; text-align: center;
  background: linear-gradient(135deg, var(--clr-accent) 0%, #4f46e5 100%);
}
.section-cta-band h2 { font-size: 1.8rem; font-weight: 700; color: var(--clr-white); }
.section-cta-band p { color: rgba(255,255,255,.8); margin: .5rem 0 1.5rem; }

/* ── Footer ──────────────────────────────────────────────────────── */
.site-footer { padding: 2rem 0; text-align: center; border-top: 1px solid var(--clr-border); }
.site-footer p { font-size: .85rem; color: var(--clr-muted); }

/* ── Responsive ──────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .hero h1 { font-size: 2rem; }
  .skills-grid, .cert-grid { grid-template-columns: 1fr; }
}