/* OSCION site refresh
   - restrained mobile-first layout
   - shared styles for landing, guide, and policy page
*/

:root {
  --bg: #141433;
  --bg-soft: #1c1a43;
  --surface: rgba(255, 255, 255, 0.065);
  --surface-strong: rgba(255, 255, 255, 0.09);
  --surface-solid: rgba(20, 20, 51, 0.9);
  --stroke: rgba(255, 255, 255, 0.12);
  --stroke-strong: rgba(255, 255, 255, 0.18);
  --fg: rgba(255, 255, 255, 0.95);
  --muted: rgba(255, 255, 255, 0.72);
  --muted-soft: rgba(255, 255, 255, 0.58);
  --accent: #66b6ff;
  --accent-2: #905bed;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.32);
  --shadow-soft: 0 14px 34px rgba(0, 0, 0, 0.22);
  --radius: 24px;
  --radius-sm: 18px;
  --max-site: 1160px;
  --max-copy: 760px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  background:
    radial-gradient(1200px 700px at 50% -10%, rgba(102, 182, 255, 0.12), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(144, 91, 237, 0.18), transparent 50%),
    radial-gradient(700px 500px at 0% 100%, rgba(102, 182, 255, 0.08), transparent 55%),
    var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
}

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

a:hover {
  text-decoration: underline;
}

/* Layout */

.site-shell {
  width: min(var(--max-site), calc(100% - 32px));
  margin: 0 auto;
  padding: 24px 0 72px;
}

.site-shell-narrow {
  max-width: 840px;
}

.site-shell-article {
  width: min(1240px, calc(100% - 32px));
}

.page {
  width: min(100%, 760px);
  margin: 0 auto;
}

.site-header {
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: center;
  margin-bottom: 26px;
}

.site-header-centered {
  justify-content: center;
  align-items: center;
}

.site-header-article {
  align-items: stretch;
}

.site-footer,
.footer {
  margin-top: 24px;
  text-align: center;
  color: var(--muted-soft);
  font-size: 0.95rem;
}

/* Branding */

.brand {
  display: inline-flex;
  text-decoration: none;
}

.logo {
  width: min(250px, 84vw);
  display: block;
  filter: drop-shadow(0 12px 28px rgba(0, 0, 0, 0.34));
}

/* Shared UI */

.nav-pill,
.button,
.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 11px 16px;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: var(--surface);
  color: var(--fg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  text-decoration: none;
  transition: transform 0.18s ease, background 0.18s ease, border-color 0.18s ease;
  box-shadow: var(--shadow-soft);
}

.nav-pill:hover,
.button:hover,
.pill:hover {
  transform: translateY(-1px);
  background: var(--surface-strong);
  border-color: var(--stroke-strong);
  text-decoration: none;
}

.nav-pill-strong,
.button-primary {
  background: linear-gradient(180deg, rgba(102, 182, 255, 0.22), rgba(102, 182, 255, 0.14));
  border-color: rgba(102, 182, 255, 0.4);
}

.button-secondary {
  background: rgba(255, 255, 255, 0.045);
}

.button-full {
  width: 100%;
}

.header-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.text-link {
  display: inline-flex;
  gap: 0.35rem;
  align-items: center;
  font-weight: 600;
}

.eyebrow {
  margin: 0 0 10px;
  font-family: "Barlow Condensed", system-ui, sans-serif;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
}

.eyebrow-light {
  color: rgba(255, 255, 255, 0.82);
}

.text-link-light {
  color: #fff;
}

.text-link-light:hover {
  color: #fff;
  text-decoration: underline;
}

.microcopy,
.small {
  color: var(--muted-soft);
  font-size: 0.95rem;
}

/* Panels / cards */

.panel,
.card {
  background: linear-gradient(180deg, rgba(0, 0, 0, 0.09), rgba(0, 0, 0, 0.37));
  border: 1px solid var(--stroke);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.panel {
  padding: 24px;
}

.card {
  padding: 22px;
}

.panel-hero {
  padding: clamp(24px, 4vw, 40px);
}

.summary-card,
.inner-cta,
.freq-card,
.myth-card,
.faq-item {
  background: rgba(255, 255, 255, 0.035);
  border: 1px solid var(--stroke);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.03);
}

.summary-card,
.inner-cta {
  border-radius: var(--radius-sm);
}

.summary-card {
  padding: 22px;
}

.freq-card,
.myth-card {
  padding: 18px;
  border-radius: 18px;
}

.faq-item {
  border-radius: 18px;
  padding: 0;
  overflow: hidden;
}

/* Landing page */

.stack {
  display: grid;
  gap: 16px;
}

.hero-grid,
.feature-grid,
.article-layout,
.freq-grid {
  display: grid;
  gap: 18px;
}

.hero-grid {
  align-items: stretch;
  margin-bottom: 18px;
}

.feature-grid {
  margin: 18px 0;
}

.panel.panel-start-here {
  background: linear-gradient(180deg, #905bed, #4b2296);
  border-color: rgba(255, 255, 255, 0.14);
}

.panel-start-here h2,
.panel-start-here p,
.panel-start-here li {
  color: #fff;
}

.panel-link {
  display: block;
  color: inherit;
  text-decoration: none;
}

.panel-link:hover,
.panel-link:focus-visible {
  text-decoration: none;
}

.panel-link:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.75);
  outline-offset: 3px;
}

.panel-start-here .text-link {
  font-size: 1.08rem;
  font-weight: 700;
  margin-top: 1.1rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.cta-row-tight {
  margin-top: 18px;
}

.feature-card h2,
.feature-copy h2 {
  max-width: 17ch;
}

.feature-list,
.toc-list,
.references-list {
  margin: 0;
  padding-left: 1.2rem;
}

.feature-list li,
.references-list li {
  margin-bottom: 0.55rem;
}

.panel-feature {
  display: grid;
  gap: 18px;
  align-items: center;
}

.feature-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.feature-grid-muted .feature-card {
  background: rgba(0, 0, 0, 0.011);
  border-color: rgba(0, 0, 0, 0.05);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.34);
}

.feature-grid-muted .feature-card h2 {
  opacity: 0.92;
}

.feature-grid-muted .feature-card p {
  color: var(--muted-soft);
}

.feature-grid-muted .eyebrow {
  color: rgba(102, 182, 255, 0.82);
}

/* Type */

h1,
h2,
h3,
summary {
  font-family: "Barlow Condensed", system-ui, sans-serif;
  color: #fff;
}

h1 {
  margin: 0 0 10px;
  font-size: clamp(2.35rem, 7vw, 4.35rem);
  line-height: 0.98;
  letter-spacing: 0.01em;
  text-transform: uppercase;
}

h2 {
  margin: 0 0 14px;
  font-size: clamp(1.55rem, 4vw, 2.25rem);
  line-height: 1.02;
  letter-spacing: 0.01em;
}

h3 {
  margin: 0 0 8px;
  font-size: clamp(1.05rem, 2.5vw, 1.35rem);
  line-height: 1.1;
  text-transform: uppercase;
}

.lede,
.article-dek {
  max-width: 62ch;
  font-size: clamp(1.05rem, 1rem + 0.35vw, 1.28rem);
  color: var(--muted);
}

/* Article layout */

.article-layout {
  align-items: start;
}

.toc-card {
  position: sticky;
  top: 18px;
}

.toc-list {
  list-style: none;
  padding-left: 0;
  margin-top: 0;
}

.toc-list li {
  margin-bottom: 0.55rem;
}

.toc-list a {
  color: var(--muted);
}

.article-card {
  padding: clamp(20px, 3vw, 34px);
}

.article-hero {
  padding-bottom: 22px;
  border-bottom: 1px solid var(--stroke);
  margin-bottom: 24px;
}

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  color: var(--muted-soft);
  font-size: 0.92rem;
}

.meta-row span {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.meta-row span:not(:last-child)::after {
  content: "•";
  color: var(--muted-soft);
  margin-left: 0.5rem;
}

.prose {
  max-width: var(--max-copy);
}

.prose p,
.prose ul,
.prose ol,
.prose .freq-grid,
.prose .myth-stack,
.prose .faq-stack,
.prose .references-list,
.prose .inner-cta {
  margin-top: 0;
  margin-bottom: 1.1rem;
}

.prose p,
.prose li {
  color: #dbdbdb;
}

.prose strong,
.prose h2,
.prose h3 {
  color: #ffffff;
}

.prose section {
  position: relative;
}

.prose section+section {
  margin-top: 3rem;
}

.prose section:not(:first-child) {
  padding-top: 1.4rem;
  border-top: 1px solid rgba(255, 255, 255, 0.07);
}

.prose section>h2 {
  margin-bottom: 1.1rem;
}

.prose section>p:first-of-type {
  color: var(--fg);
}

.prose ul,
.prose ol {
  padding-left: 1.25rem;
}

.prose li {
  margin-bottom: 0.5rem;
}

.prose sup {
  line-height: 0;
  font-size: 0.75em;
}

.prose sup a {
  color: var(--accent);
  text-decoration: none;
}

/* Article feature blocks */

.summary-card-featured {
  background: linear-gradient(180deg, #4f2a8d, #210f42);
  border: 1px solid rgba(255, 255, 255, 0.16);
  box-shadow: var(--shadow);
}

.summary-card-featured h2,
.summary-card-featured p,
.summary-card-featured li {
  color: #fff;
}

.summary-card-featured sup a {
  color: rgba(255, 255, 255, 0.9);
}

.summary-card-featured .button-secondary {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 255, 255, 0.22);
}

.summary-card-featured .button-secondary:hover {
  background: rgba(255, 255, 255, 0.18);
  border-color: rgba(255, 255, 255, 0.28);
}

.section-feature {
  padding: 24px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 22px;
  background: rgba(0, 0, 0, 0.335);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.025);
}

.section-feature.section-feature-soft {
  background: rgba(0, 0, 0, 0.125);
  border-color: rgba(0, 0, 0, 0.08);
}

.section-feature>h2 {
  margin-bottom: 1rem;
}

.section-feature>p:last-child,
.section-feature>ul:last-child,
.section-feature>ol:last-child,
.section-feature>div:last-child {
  margin-bottom: 0;
}

#common-binaural-beat-frequencies .freq-grid,
#common-myths-and-misconceptions .myth-stack,
#faq .faq-stack {
  margin-top: 1.35rem;
}

#what-binaural-beats-feel-like ul,
#how-to-listen-safely ul,
#how-to-try-binaural-beats-for-yourself ol {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--stroke);
  border-radius: 18px;
  padding: 18px 18px 18px 2.2rem;
}

#faq,
#final-thoughts,
#references {
  margin-top: 0.5rem;
}

#final-thoughts {
  padding: 22px 24px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

#references {
  padding-top: 0.25rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

/* Article subcomponents */

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

.freq-card h3 {
  font-size: 1.08rem;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  list-style: none;
  padding-left: 0;
}

.tag-list li {
  margin: 0;
  padding: 10px 14px;
  border-radius: 18px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.05);
  color: var(--fg);
  line-height: 1.45;
  min-width: 0;
}

#how-do-binaural-beats-work .tag-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

#how-do-binaural-beats-work .tag-list li {
  border-radius: 999px;
  padding: 12px 18px;
}

.myth-stack,
.faq-stack {
  display: grid;
  gap: 12px;
}

.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 16px 18px;
  font-size: 1.12rem;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item p {
  padding: 0 18px 18px;
  margin: 0;
  color: var(--muted);
}

.references-list a {
  word-break: break-word;
}

/* Misc */

.hgroup {
  margin: 8px 0 18px;
  text-align: center;
}

.hr {
  height: 1px;
  border: 0;
  background: var(--stroke);
  margin: 22px 0;
}

/* Responsive */

@media (min-width: 760px) {
  .site-shell {
    width: min(var(--max-site), calc(100% - 48px));
    padding-top: 34px;
  }

  .site-header {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

  .site-header-centered {
    flex-direction: column;
    justify-content: center;
    align-items: center;
  }

  .site-header-article {
    margin-bottom: 28px;
  }

  .hero-grid {
    grid-template-columns: minmax(0, 1.45fr) minmax(300px, 0.9fr);
  }

  .feature-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .panel-feature {
    grid-template-columns: minmax(0, 1.35fr) auto;
  }

  .article-layout {
    grid-template-columns: 280px minmax(0, 1fr);
  }

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

  .freq-card-wide {
    grid-column: span 2;
  }

  .toc-card {
    max-height: calc(100vh - 36px);
    overflow: auto;
  }
}

@media (max-width: 759px) {
  .article-layout {
    grid-template-columns: 1fr;
  }

  .toc-card {
    position: static;
    top: auto;
    max-height: none;
    overflow: visible;
    margin-bottom: 16px;
  }

  .toc-list {
    display: grid;
    gap: 0.35rem;
  }

  .meta-row span::after {
    content: none !important;
  }

  .nav-pill,
  .button {
    width: 100%;
  }

  .header-actions,
  .cta-row,
  .feature-actions {
    flex-direction: column;
  }

  .brand,
  .site-header,
  .site-header-article {
    align-items: center;
  }
}

@media (max-width: 640px) {
  .logo {
    width: min(180px, 58vw);
  }

  #how-do-binaural-beats-work .tag-list li {
    border-radius: 20px;
    padding: 14px 16px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .nav-pill,
  .button,
  .pill {
    transition: none;
  }
}

/* Oscion Labs */

.site-shell-labs {
  max-width: 980px;
}

.labs-hero {
  display: grid;
  gap: 18px;
  margin-bottom: 18px;
}

.labs-grid {
  display: grid;
  gap: 18px;
  margin: 18px 0 0;
}

.lab-card {
  display: grid;
  gap: 12px;
  align-content: start;
}

.lab-card h2 {
  max-width: none;
}

.lab-status {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  width: fit-content;
  padding: 8px 12px;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.lab-status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 14px rgba(102, 182, 255, 0.45);
}

.lab-status-muted .lab-status-dot {
  background: rgba(255, 255, 255, 0.4);
  box-shadow: none;
}

.lab-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 4px;
}

.lab-note {
  margin: 0;
  color: var(--muted-soft);
  font-size: 0.95rem;
}

.lab-page-copy {
  max-width: 60ch;
}

.lab-frame-card {
  display: grid;
  gap: 14px;
}

.lab-frame-card .button {
  width: fit-content;
}

@media (min-width: 760px) {
  .labs-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}