/* ===========================================================
   SectionZero.ai — base styles
   Palette: primary blue #1e3f68, white dominant, silver accent
   =========================================================== */

:root {
  --blue:        #1e3f68;
  --blue-deep:   #15293f;
  --blue-soft:   #e9eef5;
  --ink:         #1d2430;   /* dark gray for "Zero.ai" + body headings */
  --text:        #3c4250;
  --muted:       #6b7280;
  --silver:      #c7ccd6;   /* accent silver */
  --silver-100:  #f4f6f9;   /* very light silver section bg */
  --silver-200:  #e7ebf1;
  --silver-300:  #d6dbe4;
  --white:       #ffffff;
  --shadow-sm:   0 1px 3px rgba(21, 41, 63, .08);
  --shadow-md:   0 10px 30px rgba(21, 41, 63, .10);
  --shadow-lg:   0 24px 60px rgba(21, 41, 63, .16);
  --radius:      14px;
  --radius-lg:   22px;
  --maxw:        1180px;
  --font:        "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-head:   "Poppins", var(--font);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  color: var(--text);
  background: var(--white);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

a { color: var(--blue); text-decoration: none; }

h1, h2, h3, h4 { font-family: var(--font-head); color: var(--ink); line-height: 1.18; font-weight: 700; }

.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.eyebrow {
  display: inline-block;
  font-size: .8rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--blue);
  background: var(--blue-soft);
  padding: 6px 14px;
  border-radius: 999px;
  margin-bottom: 18px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 1rem;
  line-height: 1;
  white-space: nowrap;
  padding: 13px 26px;
  border-radius: 10px;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: transform .15s ease, box-shadow .2s ease, background .2s ease, color .2s ease;
}
.btn-primary { background: var(--blue); color: #fff; box-shadow: var(--shadow-sm); }
.btn-primary:hover { background: var(--blue-deep); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-ghost { background: #fff; color: var(--blue); border-color: var(--silver-300); }
.btn-ghost:hover { border-color: var(--blue); transform: translateY(-2px); }
.btn-sm { padding: 10px 20px; font-size: .95rem; }

/* ===========================================================
   NAVBAR
   =========================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(150%) blur(10px);
  border-bottom: 1px solid var(--silver-200);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.brand { display: flex; align-items: center; gap: 11px; }
.brand img { width: 38px; height: auto; }
.brand-text { font-family: var(--font-head); font-size: 1.5rem; letter-spacing: -.01em; }
.navbar .brand-text { font-size: 2rem; }
.navbar .brand img { width: 42px; }
.brand-text .s1 { font-weight: 800; color: var(--blue); }      /* Section: thick + blue */
.brand-text .s2 { font-weight: 400; color: var(--ink); }       /* Zero.ai: skinny + dark */

.nav-links { display: flex; align-items: center; gap: 30px; list-style: none; }
.nav-links a {
  font-size: .98rem;
  font-weight: 500;
  color: var(--ink);
  position: relative;
  padding: 4px 0;
}
.nav-links a:not(.btn)::after {
  content: "";
  position: absolute; left: 0; bottom: -2px;
  width: 0; height: 2px; background: var(--blue);
  transition: width .22s ease;
}
.nav-links a:not(.btn):hover::after { width: 100%; }

/* Nav "Get Started" button — keep button styling, not link styling */
.nav-links a.btn { color: #fff; padding: 10px 22px; line-height: 1; white-space: nowrap; font-weight: 700; }
.nav-links a.btn:hover { color: #fff; }
.nav-links a.btn-ghost { color: var(--blue); }

.nav-toggle {
  display: none;
  background: none; border: none; cursor: pointer;
  width: 42px; height: 42px;
}
.nav-toggle span {
  display: block; width: 24px; height: 2px; margin: 5px auto;
  background: var(--ink); border-radius: 2px; transition: .25s;
}

/* ===========================================================
   HERO
   =========================================================== */
.hero {
  position: relative;
  background: linear-gradient(180deg, #fff 0%, var(--silver-100) 100%);
  overflow: hidden;
  border-bottom: 1px solid var(--silver-200);
}
.hero-inner {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  align-items: center;
  gap: 40px;
  padding: 36px 0 0;   /* tighter gap under navbar; no bottom padding so photo sits flush */
}
.hero h1 { font-size: clamp(2.3rem, 4.6vw, 3.6rem); font-weight: 800; letter-spacing: -.02em; }
.hero h1 .accent { color: var(--blue); }
.hero p.lead { font-size: 1.18rem; color: var(--muted); margin: 34px 0 44px; max-width: 540px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-copy {
  align-self: stretch;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: flex-start;     /* eyebrow stays at top; controlled spacing below */
  padding: 14px 0 46px;
}
.hero-copy .eyebrow { margin-bottom: 30px; }
.hero-meta { display: flex; gap: 28px; margin-top: 34px; }
.hero-meta .stat { display: flex; flex-direction: column; }
.hero-meta .num { font-family: var(--font-head); font-weight: 800; font-size: 1.5rem; color: var(--ink); }
.hero-meta .lbl { font-size: .82rem; color: var(--muted); }

.hero-photo { position: relative; display: flex; justify-content: flex-end; align-items: flex-end; align-self: end; }
.hero-photo .blob {
  position: absolute;
  width: 108%; aspect-ratio: 1/1;
  bottom: -6%;
  background: radial-gradient(circle at 50% 45%, var(--blue) 0%, var(--blue) 38%, transparent 70%);
  opacity: .10;
  border-radius: 50%;
  z-index: 0;
}
.hero .hero-watermark {
  position: absolute;
  z-index: 0;
  width: 620px;
  max-width: none;
  left: 50.5%;
  top: 23%;
  transform: translate(-50%, -50%);
  opacity: .08;
  pointer-events: none;
  user-select: none;
}
.hero-photo img { position: relative; z-index: 1; width: auto; max-width: 100%; max-height: 720px; filter: drop-shadow(0 24px 40px rgba(21,41,63,.22)); }

/* ===========================================================
   TRUST STRIP
   =========================================================== */
.trust {
  background: var(--white);
  border-bottom: 1px solid var(--silver-200);
}
.trust-inner {
  display: flex; flex-wrap: wrap; align-items: center; justify-content: center;
  gap: 14px 44px; padding: 26px 0;
  color: var(--muted); font-size: .95rem;
}
.trust-inner strong { color: var(--ink); }
.trust-inner .dot { width: 5px; height: 5px; border-radius: 50%; background: var(--silver); }

/* ===========================================================
   SECTION GENERICS
   =========================================================== */
.section { padding: 84px 0; }
#courses { padding-top: 48px; }   /* sit closer to the hero */
.section.alt { background: var(--silver-100); }
.section-head { text-align: center; max-width: 680px; margin: 0 auto 52px; }
.section-head h2 { font-size: clamp(1.9rem, 3.2vw, 2.6rem); font-weight: 800; }
.section-head p { color: var(--muted); font-size: 1.1rem; margin-top: 14px; }

/* ---------- Course grid ---------- */
.course-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  column-gap: 28px;
  row-gap: 44px;
}
.course-card {
  background: #fff;
  border: 1px solid var(--silver-200);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex; flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .25s ease, border-color .2s ease;
}
.course-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: var(--silver-300); }
.course-thumb { aspect-ratio: 16/9; overflow: hidden; background: var(--silver-100); }
.course-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform .35s ease; }
.course-card:hover .course-thumb img { transform: scale(1.05); }
.course-body { padding: 22px 22px 24px; display: flex; flex-direction: column; flex: 1; }
.course-tag {
  align-self: flex-start;
  font-size: .72rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase;
  color: var(--blue); background: var(--blue-soft);
  padding: 4px 10px; border-radius: 6px; margin-bottom: 12px;
}
.course-body h3 { font-size: 1.18rem; margin-bottom: 8px; }
.course-body p { font-size: .96rem; color: var(--muted); flex: 1; }
.course-link {
  margin-top: 16px; font-weight: 600; font-size: .95rem; color: var(--blue);
  display: inline-flex; align-items: center; gap: 6px;
}
.course-link span { transition: transform .2s ease; }
.course-card:hover .course-link span { transform: translateX(4px); }

.courses-foot { text-align: center; margin-top: 48px; }

/* ===========================================================
   ABOUT
   =========================================================== */
.about-inner {
  display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: center;
}
.about-photo { position: relative; display: flex; justify-content: center; }
.about-photo .frame {
  position: absolute; inset: auto 0 0 0; height: 78%;
  background: linear-gradient(180deg, var(--blue-soft), transparent);
  border-radius: var(--radius-lg);
  z-index: 0;
}
.about-photo img { position: relative; z-index: 1; max-height: 460px; width: auto; filter: drop-shadow(0 18px 34px rgba(21,41,63,.2)); }
.about-text h2 { font-size: clamp(1.9rem, 3vw, 2.5rem); font-weight: 800; margin-bottom: 18px; }
.about-text p { margin-bottom: 16px; font-size: 1.05rem; }
.about-signature { font-family: var(--font-head); font-weight: 700; color: var(--blue); margin-top: 8px; }

/* ===========================================================
   CTA BAND
   =========================================================== */
.cta-band { background: var(--blue); color: #fff; padding: 70px 0; text-align: center; }
.cta-band h2 { color: #fff; font-size: clamp(1.8rem, 3vw, 2.4rem); }
.cta-band p { color: #cfdbe9; max-width: 560px; margin: 14px auto 30px; font-size: 1.1rem; }
.cta-band .btn-primary { background: #fff; color: var(--blue); }
.cta-band .btn-primary:hover { background: var(--silver-100); }

/* ===========================================================
   FOOTER
   =========================================================== */
.footer { background: var(--blue-deep); color: #aab6c6; padding: 60px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 1.6fr 1fr 1fr 1fr; gap: 40px; }
.footer-brand .brand-text .s1 { color: #fff; }
.footer-brand .brand-text .s2 { color: #aab6c6; }
.footer-brand p { margin-top: 16px; font-size: .95rem; max-width: 280px; }
.footer h4 { color: #fff; font-size: .82rem; letter-spacing: .1em; text-transform: uppercase; margin-bottom: 16px; }
.footer ul { list-style: none; }
.footer ul li { margin-bottom: 10px; }
.footer ul a { color: #aab6c6; font-size: .95rem; }
.footer ul a:hover { color: #fff; }
.footer-bottom {
  margin-top: 44px; padding-top: 22px; border-top: 1px solid rgba(255,255,255,.1);
  display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px;
  font-size: .88rem;
}
.footer-bottom a { color: #aab6c6; }
.footer-bottom a:hover { color: #fff; }

/* ===========================================================
   SIMPLE CONTENT PAGES (privacy / sitemap)
   =========================================================== */
.page-hero { background: var(--silver-100); border-bottom: 1px solid var(--silver-200); padding: 56px 0; }
.page-hero h1 { font-size: clamp(2rem, 3.4vw, 2.8rem); }
.page-hero p { color: var(--muted); margin-top: 10px; }
.prose { max-width: 800px; margin: 56px auto; }
.prose h2 { font-size: 1.4rem; margin: 34px 0 12px; }
.prose p, .prose li { color: var(--text); margin-bottom: 12px; }
.prose ul { padding-left: 22px; margin-bottom: 16px; }
.sitemap-wrap { margin: 56px auto; }
.sitemap-cols { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; text-align: left; }
.sitemap-cols h3 { margin-bottom: 14px; color: var(--blue); }
.sitemap-cols ul { list-style: none; padding-left: 0; margin: 0; }
.sitemap-cols li { margin-bottom: 10px; }
.sitemap-cols li a { color: var(--text); }
.sitemap-cols li a:hover { color: var(--blue); }

/* ---------- reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ===========================================================
   RESPONSIVE
   =========================================================== */
@media (max-width: 960px) {
  .course-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-inner { grid-template-columns: 1fr; gap: 10px; padding: 56px 0 40px; }
  .hero-photo { order: -1; }
  .hero-photo img { max-height: 380px; }
  .hero p.lead { margin-inline: auto; }
  .hero-cta, .hero-meta { justify-content: center; }
  .hero { text-align: center; }
  .about-inner { grid-template-columns: 1fr; gap: 32px; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
  .sitemap-cols { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 720px) {
  .nav-links {
    position: fixed; inset: 72px 0 auto 0;
    flex-direction: column; align-items: flex-start;
    background: #fff; padding: 18px 24px 26px; gap: 4px;
    border-bottom: 1px solid var(--silver-200);
    box-shadow: var(--shadow-md);
    transform: translateY(-130%); transition: transform .3s ease;
  }
  .nav-links.open { transform: translateY(0); }
  .nav-links li { width: 100%; }
  .nav-links a { display: block; padding: 12px 0; width: 100%; }
  .nav-links .btn { margin-top: 8px; }
  .nav-toggle { display: block; }
}
@media (max-width: 560px) {
  .course-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .sitemap-cols { grid-template-columns: 1fr; }
  .hero-meta { flex-wrap: wrap; gap: 18px; }
}