* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  scroll-behavior: smooth;
}

body {
  font-family: 'Segoe UI', sans-serif;
  background: #0f172a;
  color: #e2e8f0;
  transition: background 0.3s ease, color 0.3s ease;
}

a {
  color: #38bdf8;
  text-decoration: none;
}

.container {
  max-width: 1000px;
  margin: auto;
  padding: 40px 20px;
}

/* DARK/LIGHT MODE STYLES */
body.light {
  background: #f8fafc;
  color: #000000;
}

body.light a {
  color: #0ea5e9;
}

body.light nav {
  background: rgba(248, 250, 252, 0.9);
  border-bottom: 1px solid #cbd5e1;
}

body.light .hero .btn {
  color: #000000;
}

/* NAV */
nav {
  position: sticky;
  top: 0;
  background: rgba(15, 23, 42, 0.9);
  backdrop-filter: blur(10px);
  padding: 15px 20px;
  display: flex;
  justify-content: space-between;
  z-index: 100;
  border-bottom: 1px solid #1e293b;
  transition: background 0.3s ease, border-color 0.3s ease;
}

nav a {
  margin-left: 20px;
  font-size: 14px;
}

.toggle-btn {
  padding: 6px 12px;
  border-radius: 6px;
  background: #38bdf8;
  color: #0f172a;
  font-weight: bold;
  cursor: pointer;
  border: none;
  transition: background 0.3s ease;
}

.toggle-btn:hover {
  background: #0ea5e9;
}

.active {
  color: #ffffff;
  font-weight: bold;
  border-bottom: 2px solid #38bdf8;
  padding-bottom: 2px;
}

.hero {
  text-align: center;
  padding: 80px 20px 40px;
}

.hero h1 {
  font-size: 42px;
  margin-bottom: 10px;
}

.hero p {
  color: #94a3b8;
  margin-bottom: 20px;
  transition: color 0.3s ease;
}

.btn {
  display: inline-block;
  padding: 10px 18px;
  background: #38bdf8;
  color: #0f172a;
  border-radius: 6px;
  font-weight: bold;
  margin: 5px;
  transition: background 0.3s ease;
}

.btn:hover {
  background: #0ea5e9;
}

/* SECTION */
section {
  margin-top: 60px;
}

h2 {
  margin-bottom: 20px;
  border-left: 4px solid #38bdf8;
  padding-left: 10px;
}

#about p {
  margin-bottom: 20px;
  line-height: 1.7;
}

#about p:last-child {
  margin-bottom: 0;
}

/* CARD */
.card {
  background: #1e293b;
  padding: 20px;
  border-radius: 10px;
  margin-bottom: 20px;
  transition: transform 0.2s ease, background 0.3s ease;
}

body.light .card {
  background: #e2e8f0;
  color: #000000;
}

.card:hover {
  transform: translateY(-5px);
}

.card-header {
  display: flex;
  justify-content: space-between;
  font-size: 14px;
  margin-bottom: 10px;
  color: #94a3b8;
  transition: color 0.3s ease;
}

body.light .card-header {
  color: #64748b;
}

.card h3 {
  margin-bottom: 10px;
}

ul {
  padding-left: 20px;
}

li {
  margin-bottom: 6px;
}

/* SKILLS */
.skills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.skill {
  background: #334155;
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 13px;
}

body.light .skill {
  background: #cbd5e1;
}

/* FOOTER */
footer {
  text-align: center;
  margin-top: 60px;
  padding: 20px;
  color: #64748b;
  font-size: 14px;
  transition: color 0.3s ease;
}

body.light footer {
  color: #475569;
}

body.light nav a {
  color: #1e293b;
}

body.light .active {
  color: #000000;
  border-bottom: 2px solid #0ea5e9;
}