:root {
  --spc-bg: #020617;
  --spc-bg-soft: #020617;
  --spc-primary: #1d4ed8;
  --spc-primary-soft: #3b82f6;
  --spc-text-main: #e5e7eb;
  --spc-text-muted: #9ca3af;
  --spc-card-bg: #020617;
  --spc-border-subtle: #1f2937;
  --spc-radius-lg: 18px;
  --spc-radius-pill: 999px;
  --spc-shadow-soft: 0 20px 60px rgba(15, 23, 42, 0.8);
}

/* Light theme overrides */
body.theme-light {
  --spc-bg: #f3f4f6;
  --spc-bg-soft: #f9fafb;
  --spc-primary: #1d4ed8;
  --spc-primary-soft: #3b82f6;
  --spc-text-main: #0f172a;
  --spc-text-muted: #6b7280;
  --spc-card-bg: #ffffff;
  --spc-border-subtle: #e5e7eb;
  --spc-shadow-soft: 0 18px 45px rgba(15, 23, 42, 0.16);
}

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

html,
body {
  margin: 0;
  padding: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background: radial-gradient(
    circle at top,
    #0b1120,
    var(--spc-bg) 60%,
    var(--spc-bg)
  );
  color: var(--spc-text-main);
}

body {
  min-height: 100vh;
}

/* Layout */

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header / nav */

.spc-nav {
  position: sticky;
  top: 0;
  z-index: 20;
  backdrop-filter: blur(18px);
  background: linear-gradient(
    to bottom,
    rgba(2, 6, 23, 0.9),
    rgba(2, 6, 23, 0.85)
  );
  border-bottom: 1px solid rgba(15, 23, 42, 0.9);
  box-shadow: 0 16px 35px rgba(15, 23, 42, 0.75);
}

body.theme-light .spc-nav {
  background: rgba(249, 250, 251, 0.95);
  border-bottom-color: #e5e7eb;
  box-shadow: 0 10px 25px rgba(15, 23, 42, 0.08);
}

.spc-nav.nav-scrolled {
  box-shadow: 0 16px 40px rgba(15, 23, 42, 0.9);
}

body.theme-light .spc-nav.nav-scrolled {
  box-shadow: 0 14px 32px rgba(15, 23, 42, 0.16);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 0.25rem;
}

/* Brand */

.brand {
  display: flex;
  align-items: center;
  text-decoration: none;
  gap: 0.8rem;
}

.logo {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  object-fit: contain;
  border: 1px solid rgba(148, 163, 184, 0.7);
  background: radial-gradient(circle at top, #1d4ed8, #020617);
}

body.theme-light .logo {
  background: #ffffff;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-name {
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--spc-text-main);
}

.brand-sub {
  font-size: 0.78rem;
  color: var(--spc-text-muted);
}

/* Nav links */

.links {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.links a {
  font-size: 0.85rem;
  text-decoration: none;
  color: var(--spc-text-muted);
  padding: 0.35rem 0.3rem;
  transition: color 0.15s ease, transform 0.15s ease;
}

.links a:hover {
  color: var(--spc-text-main);
  transform: translateY(-1px);
}

.nav-pill {
  border-radius: var(--spc-radius-pill);
  padding: 0.4rem 0.9rem;
  border: 1px solid rgba(37, 99, 235, 0.7);
  background: linear-gradient(
    135deg,
    rgba(15, 23, 42, 0.85),
    rgba(15, 23, 42, 0.95)
  );
  color: #e5edff !important;
}

body.theme-light .nav-pill {
  background: #1d4ed8;
  border-color: #1d4ed8;
  color: #f9fafb !important;
}

/* Theme toggle button */

.theme-toggle {
  border-radius: var(--spc-radius-pill);
  border: 1px solid rgba(148, 163, 184, 0.8);
  background: rgba(15, 23, 42, 0.95);
  color: var(--spc-text-main);
  font-size: 0.78rem;
  padding: 0.3rem 0.65rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  cursor: pointer;
}

body.theme-light .theme-toggle {
  background: #ffffff;
  border-color: #d1d5db;
}

.theme-icon {
  font-size: 0.9rem;
}

.theme-label {
  font-size: 0.76rem;
}

/* Mobile nav toggle */

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.15rem;
}

.nav-toggle .bar {
  display: block;
  width: 22px;
  height: 2px;
  background-color: var(--spc-text-main);
  margin: 4px 0;
  border-radius: 999px;
}

/* Hero */

.hero {
  padding: 3.25rem 0 2.75rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1.1fr);
  gap: 2.4rem;
  align-items: center;
}

.hero-text h1 {
  font-size: clamp(2rem, 3vw, 2.6rem);
  margin: 0.3rem 0 0.8rem;
  line-height: 1.2;
}

.hero-text .accent {
  display: block;
  color: #bfdbfe;
}

body.theme-light .hero-text .accent {
  color: #1d4ed8;
}

.hero-text .lead {
  font-size: 0.95rem;
  color: var(--spc-text-muted);
  max-width: 28rem;
  margin-bottom: 1.6rem;
}

.eyebrow {
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: #93c5fd;
  margin-bottom: 0.1rem;
}

/* CTA buttons */

.cta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1.1rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.3rem;
  border-radius: var(--spc-radius-pill);
  font-size: 0.9rem;
  font-weight: 500;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.14s ease, box-shadow 0.14s ease, background 0.14s ease,
    border-color 0.14s ease;
}

.btn.solid {
  background: linear-gradient(
    135deg,
    var(--spc-primary),
    var(--spc-primary-soft)
  );
  color: #f9fafb;
  box-shadow: 0 16px 40px rgba(37, 99, 235, 0.45);
}

.btn.solid:hover {
  transform: translateY(-1px);
  box-shadow: 0 20px 45px rgba(30, 64, 175, 0.7);
}

.btn.outline {
  border-color: rgba(148, 163, 184, 0.7);
  background: rgba(15, 23, 42, 0.95);
  color: var(--spc-text-main);
}

body.theme-light .btn.outline {
  background: #ffffff;
}

.btn.outline:hover {
  border-color: rgba(191, 219, 254, 0.85);
}

/* Meta strip and back link */

.meta-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 0.3rem;
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  color: var(--spc-text-muted);
  background: rgba(15, 23, 42, 0.9);
  border-radius: var(--spc-radius-pill);
  padding: 0.35rem 0.75rem;
  border: 1px solid rgba(31, 41, 55, 0.85);
}

body.theme-light .meta-item {
  background: #ffffff;
  border-color: #e5e7eb;
}

.dot {
  width: 8px;
  height: 8px;
  border-radius: 999px;
}

.dot.online {
  background-color: #22c55e;
}

.dot.secure {
  background-color: #3b82f6;
}

.back-eduease {
  margin-top: 0.9rem;
  font-size: 0.8rem;
}

.back-eduease a {
  color: #bfdbfe;
  text-decoration: none;
}

body.theme-light .back-eduease a {
  color: #1d4ed8;
}

#download-btn {
  color: var(--spc-text-main);
}

/* Hero panel */

.hero-panel {
  background: radial-gradient(
    circle at top left,
    rgba(37, 99, 235, 0.2),
    rgba(15, 23, 42, 0.98)
  );
  border-radius: 22px;
  border: 1px solid rgba(148, 163, 184, 0.6);
  box-shadow: var(--spc-shadow-soft);
  padding: 1.4rem 1.2rem;
}

body.theme-light .hero-panel {
  background: #ffffff;
  border-color: #e5e7eb;
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.1rem;
  font-size: 0.78rem;
}

.panel-title {
  color: var(--spc-text-muted);
}

.panel-badge {
  border-radius: var(--spc-radius-pill);
  padding: 0.25rem 0.7rem;
  background: rgba(15, 23, 42, 0.98);
  border: 1px solid rgba(129, 140, 248, 0.9);
  color: #e5edff;
}

body.theme-light .panel-badge {
  background: #1d4ed8;
  border-color: #1d4ed8;
}

.panel-body {
  border-radius: 16px;
  background: rgba(15, 23, 42, 0.98);
  border: 1px solid rgba(31, 41, 55, 0.9);
  padding: 0.9rem 0.95rem;
  font-size: 0.8rem;
}

body.theme-light .panel-body {
  background: #f9fafb;
  border-color: #e5e7eb;
}

.panel-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 0.1rem;
  border-bottom: 1px dashed rgba(55, 65, 81, 0.85);
}

body.theme-light .panel-row {
  border-bottom-color: #d1d5db;
}

.panel-row:last-child {
  border-bottom: none;
}

.panel-row span {
  color: var(--spc-text-muted);
}

.panel-row .value {
  font-weight: 500;
  color: var(--spc-text-main);
}

.panel-footer {
  margin-top: 1rem;
  text-align: right;
}

.panel-link {
  font-size: 0.82rem;
  text-decoration: none;
  color: #bfdbfe;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

body.theme-light .panel-link {
  color: #1d4ed8;
}

.panel-link .arrow {
  font-size: 0.95rem;
}

/* Section headers */

.section-header {
  text-align: center;
  margin-bottom: 1.8rem;
}

.section-header h2 {
  font-size: 1.4rem;
  margin-bottom: 0.3rem;
}

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

/* Features */

.features {
  padding: 2.75rem 0 2.2rem;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem;
}

.card {
  background: radial-gradient(
    circle at top,
    rgba(37, 99, 235, 0.12),
    rgba(15, 23, 42, 0.98)
  );
  border-radius: var(--spc-radius-lg);
  border: 1px solid rgba(31, 41, 55, 0.9);
  padding: 1.2rem 1rem 1.1rem;
  box-shadow: 0 16px 35px rgba(15, 23, 42, 0.85);
  transition: transform 0.16s ease, box-shadow 0.16s ease,
    border-color 0.16s ease;
}

body.theme-light .card {
  background: #ffffff;
  border-color: #e5e7eb;
  box-shadow: 0 14px 32px rgba(15, 23, 42, 0.12);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.92);
  border-color: rgba(59, 130, 246, 0.9);
}

body.theme-light .card:hover {
  box-shadow: 0 20px 45px rgba(15, 23, 42, 0.16);
}

.card-icon {
  width: 34px;
  height: 34px;
  border-radius: 12px;
  background: rgba(15, 23, 42, 0.96);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 0.7rem;
  font-size: 1.15rem;
}

body.theme-light .card-icon {
  background: #1d4ed8;
  color: #f9fafb;
}

.card h3 {
  margin: 0 0 0.4rem;
  font-size: 1rem;
}

.card p {
  font-size: 0.86rem;
  color: var(--spc-text-muted);
  margin-bottom: 0.9rem;
}

.card .more {
  font-size: 0.8rem;
  text-decoration: none;
  color: #bfdbfe;
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
}

body.theme-light .card .more {
  color: #1d4ed8;
}

/* How it works */

.how-it-works {
  padding: 2.5rem 0 2.8rem;
  border-top: 1px solid rgba(15, 23, 42, 0.92);
}

body.theme-light .how-it-works {
  border-top-color: #e5e7eb;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1.2rem;
}

.step {
  background: rgba(15, 23, 42, 0.98);
  border-radius: var(--spc-radius-lg);
  border: 1px solid rgba(31, 41, 55, 0.9);
  padding: 1rem;
  font-size: 0.85rem;
}

body.theme-light .step {
  background: #ffffff;
  border-color: #e5e7eb;
}

.step-number {
  width: 26px;
  height: 26px;
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  background: radial-gradient(circle at top, #1d4ed8, #020617);
  color: #e5edff;
}

/* Footer */

.footer {
  padding: 1.2rem 0 1.8rem;
  border-top: 1px solid rgba(15, 23, 42, 0.95);
  background: rgba(2, 6, 23, 0.96);
}

body.theme-light .footer {
  background: #f9fafb;
  border-top-color: #e5e7eb;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.8rem;
  color: var(--spc-text-muted);
}

/* Reveal animations */

.reveal {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.45s ease-out, transform 0.45s ease-out;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal.delay-1 {
  transition-delay: 0.08s;
}

.reveal.delay-2 {
  transition-delay: 0.16s;
}

.reveal.delay-3 {
  transition-delay: 0.22s;
}

/* Responsive */

@media (max-width: 991.98px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .hero-panel {
    margin-top: 1.3rem;
  }

  .features-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .steps-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .links {
    position: absolute;
    top: 56px;
    right: 1.25rem;
    flex-direction: column;
    align-items: flex-start;
    background: rgba(15, 23, 42, 0.97);
    padding: 0.75rem 1rem;
    border-radius: 14px;
    border: 1px solid rgba(31, 41, 55, 0.9);
    box-shadow: 0 12px 30px rgba(15, 23, 42, 0.9);
    min-width: 200px;
    display: none;
  }

  body.theme-light .links {
    background: #ffffff;
    border-color: #e5e7eb;
    box-shadow: 0 12px 30px rgba(15, 23, 42, 0.18);
  }

  .links.open {
    display: flex;
  }

  .nav-toggle {
    display: block;
  }

  /* Center hero and footer on mobile */
  .hero-text,
  .hero-text .lead,
  .section-header {
    text-align: center;
    margin-left: auto;
    margin-right: auto;
  }

  .cta,
  .meta-strip,
  .back-eduease {
    justify-content: center;
  }

  .footer-inner {
    justify-content: center;
  }
}

@media (max-width: 639.98px) {
  .features-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .steps-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .footer-inner {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }
}