/* Design tokens */
:root {
  --bg: #ffffff;
  --bg-alt: #f6f8fb;
  --text: #0f172a;
  --muted: #475569;
  --border: #e2e8f0;
  --accent: #2563eb;
  --accent-600: #1d4ed8;
  --shadow: 0 10px 30px rgba(2, 6, 23, 0.06);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}
.narrow { max-width: 800px; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.8);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.logo { font-weight: 700; color: var(--text); letter-spacing: 0.5px; }
.logo span { color: var(--accent); }

.nav { display: flex; align-items: center; gap: 18px; }
.nav a { color: var(--muted); font-weight: 500; }
.nav a:hover { color: var(--text); }
.btn-small { padding: 8px 12px; border: 1px solid var(--border); border-radius: 10px; }

.nav-toggle { display: none; background: none; border: 0; cursor: pointer; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--text); margin: 5px 0; transition: 0.3s; }

/* Sections */
.section { padding: 80px 0; }
.section.alt { background: var(--bg-alt); }
.section-title { font-size: 28px; margin: 0 0 24px; letter-spacing: 0.3px; }

/* Hero */
.hero { padding-top: 96px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 40px;
  align-items: center;
}
.headline { font-size: 42px; line-height: 1.2; margin: 0 0 10px; }
.accent { color: var(--accent); }
.tagline { color: var(--muted); font-weight: 600; margin: 0 0 12px; }
.intro { color: var(--muted); margin-bottom: 20px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.avatar { width: 280px; height: 280px; margin: 0 auto; filter: drop-shadow(var(--shadow)); object-fit: cover; object-position: center; border-radius: 50%; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 18px;
  background: var(--accent);
  color: #fff;
  border-radius: 12px;
  border: 1px solid transparent;
  transition: transform 0.15s ease, background 0.2s ease, box-shadow 0.2s;
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.25);
}
.btn:hover { background: var(--accent-600); transform: translateY(-1px); text-decoration: none; }
.btn:active { transform: translateY(0); }
.btn-ghost { background: #fff; color: var(--text); border-color: var(--border); box-shadow: none; }
.btn-ghost:hover { background: var(--bg-alt); }

/* Skills */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px 24px;
}
.skill { background: #fff; padding: 16px; border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow); }
.skill-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 10px; font-weight: 600; }
.skill-val { color: var(--muted); font-weight: 600; }
.bar { height: 8px; background: #eef2ff; border-radius: 999px; overflow: hidden; }
.bar span { display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--accent), #60a5fa); border-radius: 999px; transition: width 1s ease; }

/* Projects */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.card { background: #fff; border: 1px solid var(--border); border-radius: 14px; overflow: hidden; box-shadow: var(--shadow); display: flex; flex-direction: column; cursor: pointer; }
.card-media { aspect-ratio: 16/9; background: #eef2ff; display: flex; align-items: center; justify-content: center; border-bottom: 1px solid var(--border); }
.card-media img { width: 100%; height: 100%; object-fit: cover; }
.card-body { padding: 18px; }
.card h3 { margin: 0 0 8px; font-size: 20px; }
.card p { margin: 0 0 12px; color: var(--muted); }
.tags { display: flex; gap: 8px; flex-wrap: wrap; }
.tags span { font-size: 12px; padding: 4px 8px; background: #eef2ff; color: var(--accent-600); border-radius: 999px; border: 1px solid #dbeafe; }
.card-footer { padding: 12px 18px; border-top: 1px solid var(--border); display: flex; gap: 12px; }
.link { font-weight: 600; }
.link.disabled { color: #94a3b8; pointer-events: none; }

/* Tabs for Experience / Education */
.tabs { display: flex; gap: 8px; margin-bottom: 14px; }
.tab-btn { padding: 8px 12px; border: 1px solid var(--border); border-radius: 999px; background: #fff; color: var(--muted); font-weight: 600; cursor: pointer; }
.tab-btn[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: #fff; }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

/* Timeline */
.timeline { position: relative; margin-left: 10px; }
.timeline::before { content: ""; position: absolute; top: 0; left: 10px; bottom: 0; width: 2px; background: #dbeafe; }
.t-item { position: relative; padding-left: 36px; margin: 18px 0; }
.t-marker { position: absolute; left: 2px; top: 10px; width: 16px; height: 16px; background: #fff; border: 3px solid var(--accent); border-radius: 50%; box-shadow: 0 2px 8px rgba(2,6,23,0.1); }
.t-card { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 14px; box-shadow: var(--shadow); }
.t-header { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; margin-bottom: 6px; }
.t-meta { color: var(--muted); font-weight: 600; white-space: nowrap; }

/* Contact */
.contact-form { background: #fff; padding: 18px; border-radius: 12px; border: 1px solid var(--border); box-shadow: var(--shadow); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.form-field { display: flex; flex-direction: column; gap: 8px; margin-bottom: 12px; }
label { font-weight: 600; color: var(--muted); }
input, textarea { font: inherit; padding: 12px 12px; border: 1px solid var(--border); border-radius: 10px; outline: none; }
input:focus, textarea:focus { border-color: #bfd2fe; box-shadow: 0 0 0 4px #e0e7ff; }
.form-status { margin-top: 8px; color: var(--muted); }
.socials { display: flex; gap: 16px; margin-top: 18px; flex-wrap: wrap; }
.social { font-weight: 600; }

/* Footer */
.footer { border-top: 1px solid var(--border); padding: 20px 0; background: #fff; }
.footer-grid { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.footer a { color: var(--muted); }
.footer a:hover { color: var(--text); }

/* Project Gallery */
.project-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
  margin-top: 20px;
}
.gallery-item {
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow);
}
.gallery-item img,
.gallery-item video {
  width: 100%;
  height: 200px;
  object-fit: cover;
  display: block;
}

/* Expandable Skills */
.skills-more {
  margin-top: 20px;
  text-align: center;
}
.skills-toggle {
  background: none;
  border: 1px solid var(--accent);
  color: var(--accent);
  padding: 8px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s ease;
}
.skills-toggle:hover {
  background: var(--accent);
  color: #fff;
}
.skills-extra {
  display: none;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.skills-extra.show {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 12px;
}
.skills-extra .skill {
  background: #f8fafc;
  border: 1px solid #e2e8f0;
}

/* Reveal animations */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity 600ms ease, transform 600ms ease; }
.reveal.in-view { opacity: 1; transform: translateY(0); }

/* Responsive */
@media (max-width: 980px) {
  .projects-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-grid { grid-template-columns: 1fr; }
  .avatar { width: 220px; height: 220px; }
}
@media (max-width: 720px) {
  .nav { position: fixed; inset: 64px 0 auto 0; background: rgba(255,255,255,0.98); backdrop-filter: blur(8px); border-bottom: 1px solid var(--border); padding: 16px 20px; transform: translateY(-120%); transition: transform 0.25s ease; flex-direction: column; gap: 12px; }
  .nav.open { transform: translateY(0); }
  .nav-toggle { display: inline-block; }
  .section { padding: 64px 0; }
  .skills-grid { grid-template-columns: 1fr; }
  .projects-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
}