:root {
  /* Design tokens – spacing */
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 5rem;
  --gap: var(--space-lg);

  /* Design tokens – typography */
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.75rem;

  /* Colors & layout */
  --primary: #2f4b7c;
  --primary-light: #4f6aa6;
  --accent-soft: #f0f4ff;
  --background: #ffffff;
  --background-light: #f7f9fc;
  --text: #3a3e45;
  --muted: #6c7685;
  --hero-bg: url('https://tabmark.app/images/hero.png');
  --max-width: 1400px;
  --feature-img-max: 360px;
}

/* Global reset & utilities */
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  /* Always show vertical scrollbar (even if content fits) */
  overflow-y: scroll;
}
body {
  margin: 0;
  padding: 0;
  font-family: 'Inter', sans-serif;
  background: var(--background);
  color: var(--text);
  line-height: 1.6;
}
body.no-scroll {
  overflow: hidden; /* hide all overflow */
  height: 100vh; /* ensure body cannot stretch beyond viewport */
}
/* hide the back-to-top whenever the menu is open */
body.no-scroll #back-to-top {
  display: none !important; /* JS adds display:block inline, so we need important */
  /* or: visibility: hidden; pointer-events: none; opacity: 0; */
}

h1,
h2,
h3,
h4,
h5,
h6 {
  line-height: 1.2;
}

a {
  text-decoration: none;
  color: inherit;
}
img {
  display: block;
  width: 100%;
  height: auto;
}

form {
  display: flex;
  align-items: center;
  flex-wrap: wrap; /* allow items to wrap onto new rows */
  gap: 1rem; /* optional spacing between items */
  max-width: 400px;
}

@media (max-width: 600px) {
  form > * {
    /* stack the input and button on mobile */
    width: 100%;
  }
}

input[type='email'],
input[type='text'],
input[type='password'] {
  flex: 1 1 auto;
  min-width: 0;
  padding: 0.75rem 1rem;
  border: 1px solid #ddd;
  border-radius: 0.375rem;
  font-size: 1rem;
  font-family: 'Inter', sans-serif;
}
input[type='email']:focus,
input[type='text']:focus,
input[type='password']:focus {
  border-color: #2680cc;
  box-shadow: 0 0 0 3px rgba(38, 128, 204, 0.3);
  outline: none;
}

button.cta-btn {
  flex: 0 0 auto;
  padding: 0.75rem 1.25rem;
  border-radius: 0.375rem;
  background-color: #2680cc;
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s ease;
  white-space: nowrap;
}
button.cta-btn:hover {
  background-color: #1f639f;
}

.text-center {
  text-align: center;
  margin: 0 auto;
}

.container {
  width: 90%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--gap);
}

.container-inner {
  padding: var(--gap) 0;
}

/* Skip-to-content */
.skip-link {
  position: absolute;
  top: -3rem;
  left: 0;
  background: var(--primary);
  color: #fff;
  padding: var(--space-sm) var(--space-md);
  z-index: 200;
  transition: top 0.3s, left 0.3s;
}
.skip-link:focus {
  top: 0;
  left: var(--space-md);
}

/* Screen-reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Focus outlines */
a:focus,
button:focus {
  outline: 2px dashed var(--primary);
  outline-offset: 4px;
}

/* HEADER & NAV */
header {
  position: sticky;
  top: 0;
  background: var(--background);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.05);
  z-index: 100;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--gap) 0;
}
.logo {
  height: 36px;
}

/* Nav links + underline on non-CTA */
nav {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* .nav-menu a::after {
  content: '';
  position: absolute;
  width: 100%;
  transform: scaleX(0);
  height: 2px;
  bottom: -4px;
  left: 0;
  background-color: #2b477e;
  transform-origin: bottom right;
  transition: transform 0.3s ease-out;
} */

nav a {
  position: relative;
  color: var(--muted);
  font-weight: 500;
  font-size: var(--font-size-sm);
  text-decoration: none;
}
nav a:not(.cta-btn)::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.3s ease;
}
nav a:not(.cta-btn):hover::after,
nav a:not(.cta-btn):focus::after,
nav a.active:not(.cta-btn)::after {
  width: 100%;
}
nav a.cta-btn {
  background: var(--primary);
  color: #fff;
  padding: var(--space-sm) var(--space-md);
  border-radius: 6px;
  font-weight: 600;
  transition: background 0.2s ease;
}
nav a.cta-btn:hover {
  background: var(--primary-light);
}

/* Hamburger toggle (hidden on desktop) */
.nav-toggle {
  display: none;
  background: transparent;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  margin-left: auto;
  margin-right: 0;
  color: var(--muted);
  position: relative;
  width: 32px;
  height: 32px;
  font-size: 24px;
  transition: transform 0.3s ease;
}
@media (max-width: 640px) {
  .header-inner {
    padding: var(--space-md) var(--gap);
  }
  .nav-toggle {
    display: block;
  }
  .nav-toggle.open {
    transform: rotate(90deg);
  }
  .nav-menu {
    display: none;
    flex-direction: column;
    width: 100%;
    background: var(--background);
    position: absolute;
    top: 100%;
    left: 0;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    height: 100vh;
    padding: 20px;
    overflow-y: auto;
  }
  .nav-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--background);
    flex-direction: column;
    transform: translateY(-100%);
    transition: transform 0.3s ease;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);

    opacity: 0;
  }
  .nav-menu.open {
    transform: translateY(0);
    display: flex;
    opacity: 1;
  }

  .nav-menu a {
    display: block;
    margin: var(--gap) 0;
    font-size: var(--font-size-lg);
  }
}

/* LAYOUT */
main.page {
  padding: var(--space-lg) var(--space-4xl);
  max-width: 1220px;
  margin: 0 auto;
}

@media (max-width: 640px) {
  main.page {
    padding: var(--space-md) var(--space-lg);
  }
}

/* HERO */
.hero {
  background-color: #2680cc;
  background: var(--hero-bg) center/cover no-repeat;
  /*background: linear-gradient(135deg, #2680cc 0%, #cae5fe 100%);*/
  padding: var(--space-4xl) 0;
  text-align: center;
  color: #fff;
  position: relative;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0; /* top/right/bottom/left = 0 */
  background: rgba(0, 0, 0, 0.5); /* tweak opacity to taste */
  z-index: 1;
}

.hero .content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 4rem 1rem;
}

.hero::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
}
.hero .container {
  position: relative;
  z-index: 1;
}
.hero h1 {
  font-family: 'Poppins', sans-serif;
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 700;
  margin-bottom: var(--space-md);
}
.hero p {
  font-size: var(--font-size-lg);
  max-width: 600px;
  margin: 0 auto var(--space-xl);
}
.btn-primary {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  padding: var(--space-sm) var(--space-2xl);
  font-size: var(--font-size-md);
  border-radius: 8px;
  transition: background 0.2s ease, transform 0.1s ease;
}
.btn-primary:hover {
  background: var(--primary-light);
  transform: translateY(-1px);
}

/* FEATURES */
.feature-block:nth-of-type(even) {
  background: var(--accent-soft);
}
.feature-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  padding: var(--space-3xl) var(--gap);
  max-width: var(--max-width);
  margin: 0 auto;
}
.feature-block:nth-of-type(even) .feature-content {
  direction: rtl;
}
.feature-block:nth-of-type(even) .feature-text {
  direction: ltr;
  text-align: left;
}
.feature-text h2 {
  font-size: var(--font-size-xl);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: var(--space-sm);
}
.feature-text p {
  font-size: var(--font-size-md);
  color: var(--muted);
  margin-bottom: var(--space-md);
}
.feature-text ul {
  list-style: none;
  padding: 0;
  margin: 0;
}
.feature-text ul li {
  position: relative;
  padding-left: var(--space-md);
  margin-bottom: var(--space-sm);
  font-size: var(--font-size-sm);
}
.feature-text ul li::before {
  content: '›';
  position: absolute;
  left: 0;
  top: 0;
  color: var(--primary);
  font-weight: bold;
}
.feature-image {
  display: flex;
  justify-content: center;
  align-items: center;
}
.feature-image img {
  max-width: var(--feature-img-max);
  border-radius: 12px;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.feature-image img:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
}

/* Fade-in */
.fade-in-up {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Center images on mobile */
@media (max-width: 1024px) {
  .feature-content {
    grid-template-columns: 1fr;
    justify-items: center;
  }
}

/* DOWNLOAD */
#download {
  background: var(--background-light);
  text-align: center;
  padding: var(--space-3xl) var(--gap);
}
.download-card {
  background: #fff;
  border: 1px solid var(--primary);
  border-radius: 12px;
  padding: var(--space-2xl);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.05);
  max-width: 600px;
  margin: 0 auto;
}
.download-card h2 {
  font-size: var(--font-size-xl);
  letter-spacing: 0.05em;
  color: var(--primary);
  margin: 0 0 var(--space-md);
  text-transform: uppercase;
}
.download-card p {
  color: var(--muted);
  margin-bottom: var(--space-lg);
}
.download-card small {
  display: block;
  margin-top: var(--space-xl);
  font-size: var(--font-size-sm);
  color: var(--muted);
}
.btn-ghost {
  display: inline-block;
  border: 2px dashed var(--primary);
  color: var(--primary);
  padding: var(--space-sm) var(--space-2xl);
  border-radius: 8px;
  margin-bottom: var(--space-sm);
  pointer-events: none; /* keeps it non-clickable */
  opacity: 1; /* full contrast on the text */
}
.btn-ghost:hover {
  opacity: 0.8;
  border-style: solid;
}

form#signup-form {
  width: 80%;
  margin: 0 auto;
}

@media (max-width: 640px) {
  form#signup-form {
  }
}

@media (max-width: 640px) {
  .download-card {
    padding: var(--space-2xl) var(--gap);
  }
}

.thank-you {
  text-align: center;
  font-size: var(--font-size-xl);
}

/* FOOTER & BACK TO TOP */
footer {
  border-top: 1px solid #eee;
  color: var(--muted);
  padding: var(--space-xl) 0;
  text-align: center;
}
.footer-nav {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}
.footer-nav a {
  font-size: var(--font-size-sm);
  color: var(--muted);
}
.footer-nav a:hover {
  color: var(--primary);
}
#back-to-top {
  position: fixed;
  bottom: var(--space-2xl);
  right: var(--space-2xl);
  display: none;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  width: var(--space-2xl);
  height: var(--space-2xl);
  font-size: var(--font-size-md);
  cursor: pointer;
  opacity: 0.7;
  transition: opacity 0.3s;
  z-index: 150;
}
#back-to-top:hover {
  opacity: 1;
}

.logo-row {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: var(--space-4xl) 0;
}

.logo-row > div {
  flex-shrink: 1;
}

.logo-row > div img {
  height: 100px;
}

.logo-row > div.plus-icon {
  font-size: 64px;
  margin-left: 20px;
}