* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: #202230;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: #ffffff;
}

a {
  color: inherit;
}

.navbar {
  position: sticky;
  top: 0;
  z-index: 2;
  border-bottom: 1px solid #e5e7eb;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 14px 0;
}

.nav-links {
  display: flex;
  gap: 22px;
  align-items: center;
}

.header-logo {
  display: block;
  width: 132px;
  height: auto;
}

.download-button,
input[type="submit"] {
  border: 0;
  border-radius: 999px;
  padding: 10px 18px;
  color: #ffffff;
  background: #2f5bea;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
}

.masthead,
.section,
.support-page,
.privacy-page,
.student-verification-page {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.masthead {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(260px, 0.95fr);
  gap: 48px;
  align-items: center;
  padding: 72px 0 56px;
}

.masthead h1 {
  margin: 0 0 18px;
  font-size: clamp(42px, 7vw, 76px);
  line-height: 0.96;
}

.lead {
  color: #626778;
  font-size: 20px;
  line-height: 1.5;
}

.app-badge {
  width: 180px;
  height: auto;
}

.phone-stack {
  position: relative;
  max-width: 330px;
  margin: 0 auto;
}

.phone-stack img {
  display: block;
  width: 100%;
  border-radius: 28px;
  box-shadow: 0 20px 60px rgba(28, 39, 70, 0.18);
  transition: opacity 1.5s ease;
}

.phone-stack img + img {
  position: absolute;
  inset: 0;
  z-index: -1;
}

.gradient-band {
  color: #ffffff;
  background: linear-gradient(135deg, #2f5bea, #2a9d8f);
}

.gradient-band .section {
  padding: 54px 0;
  text-align: center;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  padding: 62px 0;
}

.feature {
  text-align: center;
}

.feature img {
  width: 44px;
  height: 44px;
}

.feature h3 {
  margin: 16px 0 8px;
}

.muted {
  color: #626778;
}

.plus-section {
  background: #f5f7fb;
}

.plus-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 220px;
  gap: 48px;
  align-items: center;
  padding: 58px 0;
}

.plus-logo {
  width: 180px;
}

footer {
  color: rgba(255, 255, 255, 0.72);
  background: #0c0f18;
  text-align: center;
  padding: 34px 16px;
}

footer a {
  margin: 0 8px;
}

.support-page,
.privacy-page,
.student-verification-page {
  padding: 72px 0;
  min-height: 58vh;
}

.support-form {
  display: grid;
  gap: 16px;
  max-width: 640px;
}

.form-row {
  display: grid;
  gap: 6px;
}

input,
textarea {
  width: 100%;
  border: 1px solid #cfd5e3;
  border-radius: 8px;
  padding: 12px;
  font: inherit;
}

textarea {
  min-height: 160px;
}

.error {
  color: #b42318;
}

.confirm {
  color: #027a48;
}

.privacy-policy {
  max-width: 860px;
  line-height: 1.65;
}

@media (max-width: 820px) {
  .masthead,
  .plus-inner {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 560px) {
  .nav-inner,
  .nav-links {
    align-items: flex-start;
    flex-direction: column;
  }

  .feature-grid {
    grid-template-columns: 1fr;
  }
}