/* ── CSS Variables ───────────────────────────────────────────────────────── */
:root {
    --python-color: #3776AB;
    --sql-color:    #F29111;
    --web-color:    #E44D26;
    --r-color:      #276DC3;
    --db-color:     #6366F1;
    --primary:      #1565C0;
    --hero-bg:      #0f1b35;
}

/* ── Reset / Base ────────────────────────────────────────────────────────── */
* { box-sizing: border-box; }

body {
    font-family: 'Poppins', sans-serif;
    color: #222;
    margin: 0;
    padding: 0;
    background: #f5f7fa;
}

/* ── Navbar ──────────────────────────────────────────────────────────────── */
nav.top-nav {
    background: var(--hero-bg);
    padding: 0 32px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 12px rgba(0,0,0,0.35);
}
nav.top-nav .brand {
    font-size: 1.25rem;
    font-weight: 700;
    color: white;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}
nav.top-nav .brand span.accent { color: #64b5f6; }

nav.top-nav .nav-links {
    display: flex;
    align-items: center;
    gap: 24px;
}
nav.top-nav .nav-links a {
    color: #cfd8dc;
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 500;
    transition: color 0.2s;
}
nav.top-nav .nav-links a:hover { color: white; }
nav.top-nav .nav-links a.btn-outline {
    border: 1px solid #64b5f6;
    color: #64b5f6;
    padding: 5px 16px;
    border-radius: 20px;
    font-size: 0.82rem;
}
nav.top-nav .nav-links a.btn-outline:hover {
    background: #64b5f6;
    color: #0f1b35;
}

/* ── Hero (shared base) ──────────────────────────────────────────────────── */
.hero {
    background: linear-gradient(135deg, var(--hero-bg) 0%, #162950 55%, #1a3a6e 100%);
    color: white;
    text-align: center;
}
.hero h1 {
    font-weight: 800;
    margin: 0 0 12px;
}
.hero h1 em {
    font-style: normal;
    color: #64b5f6;
}

/* ── Sandbox color backgrounds ───────────────────────────────────────────── */
.python-bg { background: var(--python-color); }
.sql-bg    { background: var(--sql-color); }
.web-bg    { background: var(--web-color); }
.r-bg      { background: var(--r-color); }
.db-bg     { background: var(--db-color); }

/* ── Footer ──────────────────────────────────────────────────────────────── */
footer {
    background: #0f1b35;
    color: #90a4ae;
    padding: 36px 20px 24px;
    text-align: center;
    font-size: 0.85rem;
}
footer a { color: #64b5f6; text-decoration: none; }
footer a:hover { text-decoration: underline; }
footer .footer-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 14px;
    flex-wrap: wrap;
}

/* ── Hamburger ───────────────────────────────────────────────────────────── */
.hamburger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.hamburger span {
    display: block;
    width: 24px;
    height: 2px;
    background: #cfd8dc;
    border-radius: 2px;
    transition: all 0.25s;
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ── Mobile Menu ─────────────────────────────────────────────────────────── */
.mobile-menu {
    display: none;
    flex-direction: column;
    background: #162950;
    left: 0;
    right: 0;
    z-index: 99;
    box-shadow: 0 6px 16px rgba(0,0,0,0.35);
    border-top: 1px solid rgba(255,255,255,0.08);
}
.mobile-menu.open { display: flex; }
.mobile-menu a {
    color: #cfd8dc;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    padding: 14px 24px;
    border-bottom: 1px solid rgba(255,255,255,0.07);
    transition: background 0.2s, color 0.2s;
}
.mobile-menu a:last-child { border-bottom: none; }
.mobile-menu a:hover { background: rgba(100,181,246,0.1); color: white; }
.mobile-menu a.btn-outline {
    color: #64b5f6;
    border-bottom: none;
    padding-top: 16px;
    padding-bottom: 16px;
}

/* ── Shared responsive ───────────────────────────────────────────────────── */
@media (max-width: 720px) {
    nav.top-nav .nav-links { display: none; }
    .hamburger { display: flex; }
}