/* ================================
   Minimal, Modern, Responsive CSS
   ================================ */

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

* {
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Helvetica, Arial, sans-serif;
  line-height: 1.7;
  color: var(--text-main);
  background: radial-gradient(1200px 600px at 10% -10%, rgba(79,70,229,0.12), transparent 40%),
              radial-gradient(800px 500px at 90% 10%, rgba(6,182,212,0.12), transparent 45%),
              var(--bg-main);
}

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

a {
  color: #2563eb;
  text-decoration: none;
}

/* ---- VARIABLES ---- */
:root {
  --max-width: 1100px;

  /* Brand palette */
  --accent: #4f46e5;      /* indigo-600 */
  --accent-2: #06b6d4;    /* cyan-500 */
  --accent-3: #22c55e;    /* green-500 */

  /* Surfaces */
  --bg-main: #0b1020;     /* deep slate */
  --bg-section-1: #0b1020;
  --bg-section-2: #0f172a;
  --bg-section-3: #0b1220;
  --bg-card: #0f172a;

  /* Text */
  --text-main: #e5e7eb;
  --text-muted: #9ca3af;

  /* Effects */
  --border: rgba(255,255,255,0.08);
  --shadow-sm: 0 8px 24px rgba(0,0,0,0.25);
  --shadow-lg: 0 18px 60px rgba(0,0,0,0.35);
}

@media (prefers-color-scheme: light) {
  :root {
    --bg-main: #f8fafc;
    --bg-section-1: #f8fafc;
    --bg-section-2: #eef2ff;
    --bg-section-3: #ecfeff;
    --bg-card: #ffffff;
    --text-main: #0f172a;
    --text-muted: #475569;
    --border: rgba(15,23,42,0.08);
    --shadow-sm: 0 10px 30px rgba(15,23,42,0.12);
    --shadow-lg: 0 24px 70px rgba(15,23,42,0.18);
  }
}

/* ---- LAYOUT ---- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

section {
  padding: 6rem 0;
}

/* Section theming */
#about { background: linear-gradient(180deg, var(--bg-section-1), var(--bg-section-2)); }
#projects { background: linear-gradient(180deg, var(--bg-section-2), var(--bg-section-3)); }
#contact { background: linear-gradient(180deg, var(--bg-section-3), var(--bg-section-1)); }

.section-text {
  max-width: 65ch;
  color: var(--text-muted);
}

/* ---- HEADER ---- */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 15, 35, 0.6);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

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

.logo {
  font-weight: 600;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  gap: 1.25rem;
  font-size: 0.95rem;
}

.nav-links a {
  color: var(--text-muted);
}

.nav-links a:hover {
  color: var(--accent);
}

/* ---- HERO ---- */
.hero {
  padding: 7rem 0 6rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3.5rem;
  align-items: center;
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 3.4rem);
  line-height: 1.05;
  letter-spacing: -0.04em;
  margin-bottom: 1.5rem;
}

.hero p {
  color: var(--text-muted);
  max-width: 56ch;
  margin-bottom: 2rem;
}

.hero-card {
  background: linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.02));
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: 1.75rem;
  box-shadow: var(--shadow-lg);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
  align-items: center;
}

.hero h1 {
  font-size: clamp(2.1rem, 4.5vw, 3.1rem);
  line-height: 1.08;
  letter-spacing: -0.035em;
  margin-bottom: 1.25rem;
}

.hero p {
  color: var(--text-muted);
  max-width: 52ch;
  margin-bottom: 1.75rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-card {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1.5rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ---- BUTTONS ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.25rem;
  border-radius: 999px;
  font-weight: 500;
  border: 1px solid var(--border);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #ffffff;
  box-shadow: 0 10px 30px rgba(79,70,229,0.35);
}

.btn.secondary {
  background: transparent;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.btn:hover {
  transform: translateY(-1px);
}

.btn.primary {
  background: var(--accent);
  color: #ffffff;
  border-color: var(--accent);
}

.btn.primary:hover {
  background: var(--accent-dark);
}

.btn.secondary:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* ---- PROJECTS ---- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.75rem;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 1.25rem;
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.card h3 {
  margin-bottom: 0.5rem;
}

.card p {
  color: var(--text-muted);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}

.card h3 {
  font-size: 1rem;
  margin-bottom: 0.5rem;
}

.card p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* ---- FOOTER ---- */
footer {
  background: var(--bg-section-1);
  border-top: 1px solid var(--border);
  padding: 3rem 0;
  color: var(--text-muted);
}

/* ---- RESPONSIVE ---- */
@media (max-width: 768px) {
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .nav-links {
    gap: 0.75rem;
    font-size: 0.9rem;
  }
}