/* ============================================================
   CuriOS — GitHub Pages stylesheet
   ============================================================ */

/* ---------- Reset & base ---------------------------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-bg: black;
  --color-surface: #13161e;
  --color-surface-2: #1a1e28;
  --color-border: rgba(255, 255, 255, 0.08);
  --color-text: #e8eaf0;
  --color-text-muted: #8b90a0;
  --color-accent: #f98611;
  --color-accent-2: #ffd060;
  --color-green: #3ecf8e;
  --color-red: #ff6b6b;
  --color-yellow: #ffd060;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 32px rgba(0, 0, 0, 0.4);
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

img,
svg {
  display: block;
}

/* ---------- Utilities ------------------------------------- */
.container {
  width: 100%;
  max-width: 1100px;
  margin-inline: auto;
  padding-inline: 1.5rem;
}

.gradient-text {
  background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-title {
  font-size: clamp(1.6rem, 3vw, 2.25rem);
  font-weight: 700;
  text-align: center;
  margin-bottom: 0.5rem;
}

.section-sub {
  text-align: center;
  color: var(--color-text-muted);
  font-size: 1.05rem;
  margin-bottom: 3rem;
}

/* ---------- Buttons --------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.4rem;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.15s;
  white-space: nowrap;
}

.btn:hover {
  opacity: 0.88;
  transform: translateY(-1px);
}

.btn--primary {
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-2));
  color: #fff;
}

.btn--outline {
  border: 1.5px solid var(--color-border);
  color: var(--color-text);
}

.btn--outline:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.btn--ghost {
  color: var(--color-text-muted);
}

.btn--ghost:hover {
  color: var(--color-text);
  opacity: 1;
}

/* ---------- Nav ------------------------------------------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13, 15, 20, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.nav__logo {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 1.75rem;
}

.nav__links a {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.nav__links a:hover {
  color: var(--color-text);
}

/* ---------- Hero ------------------------------------------ */
.hero {
  padding: 1rem 0 2rem;
}

.hero__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 1.5rem;
}

.hero__badge {
  display: inline-block;
  background: rgba(249, 134, 17, 0.15);
  border: 1px solid rgba(249, 134, 17, 0.35);
  color: var(--color-accent);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.3rem 0.85rem;
  border-radius: 100px;
}

.hero__headline {
  font-size: clamp(1.4rem, 6vw, 2.5rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  max-width: 700px;
}

.hero__sub {
  color: var(--color-text-muted);
  font-size: 1.1rem;
  max-width: 540px;
  line-height: 1.7;
}

.hero__sub strong {
  color: var(--color-text);
}

.hero__cta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
}

.hero__video {
  margin-top: 2.5rem;
}

/* ---------- Intro chat (CSS-only animation) --------------- */
.intro-chat {
  width: 100%;
  max-width: 820px;
  margin-top: 2.25rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  background: radial-gradient(800px 320px at 50% -20%, rgba(249, 134, 17, 0.18), transparent 60%),
              var(--color-bg);
  box-shadow: var(--shadow);
  overflow: hidden;
}

/* Scroll-driven mode (enabled by JS via data-mode="scroll") */
.intro-chat[data-mode="scroll"] .intro-chat__logo,
.intro-chat[data-mode="scroll"] .intro-chat__pill,
.intro-chat[data-mode="scroll"] .intro-chat__bubble {
  animation: none !important;
}

.intro-chat[data-mode="scroll"] .intro-chat__logo,
.intro-chat[data-mode="scroll"] .intro-chat__pill {
  opacity: 1;
  transform: none;
}

.intro-chat[data-mode="scroll"] .intro-chat__bubble {
  opacity: 0;
  transform: translateY(10px);
}

.intro-chat__top {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.85rem;
  padding: 1.75rem 1.5rem 1.25rem;
}

.intro-chat__logo {
  opacity: 0;
  transform: translateY(6px);
  animation: introFadeUp 0.55s ease forwards;
  animation-delay: 0.05s;
}

.intro-chat__pill {
  opacity: 0;
  transform: translateY(6px);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  border-radius: 999px;
  padding: 0.55rem 0.9rem;
  font-size: 0.9rem;
  animation: introFadeUp 0.55s ease forwards;
  animation-delay: 0.18s;
}

.intro-chat__thread {
  padding: 0 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  text-align: left;
}

.intro-chat__bubble {
  max-width: 76%;
  padding: 0.75rem 0.95rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
  font-size: 0.95rem;
  line-height: 1.55;
  text-align: left;
  overflow-wrap: anywhere;
  word-break: break-word;
  opacity: 0;
  transform: translateY(10px);
  animation: bubbleIn 0.45s ease forwards;
  animation-delay: var(--d, 0s);
  will-change: transform, opacity;
}

.intro-chat__bubble a {
  overflow-wrap: anywhere;
  word-break: break-word;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.intro-chat__bubble code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  padding: 0.05em 0.35em;
  border-radius: 6px;
  background: rgba(0, 0, 0, 0.22);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.intro-chat__bubble--system {
  align-self: flex-start;
  background: var(--color-surface);
  color: var(--color-text);
  border-top-left-radius: var(--radius-sm);
}

.intro-chat__bubble--user {
  align-self: flex-end;
  background: var(--color-text);
  color: var(--color-bg);
  border-color: rgba(255, 255, 255, 0.22);
  border-top-right-radius: var(--radius-sm);
}

.intro-chat__bubble--typing {
  align-self: flex-start;
  width: 84px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  background: var(--color-surface);
  color: var(--color-text-muted);
  border-top-left-radius: var(--radius-sm);
  --hold: 0.75s;
  animation:
    bubbleIn 0.35s ease forwards,
    bubbleOut 0.25s ease forwards;
  animation-delay:
    var(--d, 0s),
    calc(var(--d, 0s) + var(--hold));
}

.intro-chat__dot {
  width: 7px;
  height: 7px;
  border-radius: 999px;
  background: var(--color-text-muted);
  opacity: 0.7;
  animation: typingDot 1.05s ease-in-out infinite;
}

.intro-chat__dot:nth-child(2) { animation-delay: 0.15s; }
.intro-chat__dot:nth-child(3) { animation-delay: 0.3s; }

@keyframes introFadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes bubbleIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes bubbleOut {
  to {
    opacity: 0;
    transform: translateY(-6px);
  }
}

@keyframes typingDot {
  0%, 100% { transform: translateY(0); opacity: 0.55; }
  50% { transform: translateY(-4px); opacity: 0.95; }
}

@media (prefers-reduced-motion: reduce) {
  .intro-chat__logo,
  .intro-chat__pill,
  .intro-chat__bubble {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .intro-chat__dot {
    animation: none;
  }

  .intro-chat__bubble--typing {
    display: none;
  }
}

/* ---------- Terminal -------------------------------------- */
.terminal {
  width: 100%;
  max-width: 620px;
  margin-top: 1rem;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow);
  text-align: left;
}

.terminal__bar {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.65rem 1rem;
  background: var(--color-surface-2);
  border-bottom: 1px solid var(--color-border);
}

.terminal__dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.terminal__dot--red    { background: var(--color-red); }
.terminal__dot--yellow { background: var(--color-yellow); }
.terminal__dot--green  { background: var(--color-green); }

.terminal__title {
  flex: 1;
  text-align: center;
  font-size: 0.78rem;
  color: var(--color-text-muted);
}

.terminal__body {
  background: var(--color-surface);
  padding: 1.25rem 1.25rem 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 2;
}

.terminal__prompt {
  color: var(--color-accent);
  margin-right: 0.5rem;
}

.terminal__line--system {
  color: var(--color-text-muted);
}

.terminal__cursor {
  animation: blink 1.1s step-end infinite;
  color: var(--color-accent);
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

/* ---------- Features -------------------------------------- */
.features {
  padding: 5rem 0;
  border-top: 1px solid var(--color-border);
}

/* ---------- Demo ------------------------------------------ */
.demo {
  padding: 5rem 0;
  border-top: 1px solid var(--color-border);
}

.demo__grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
}

.demo__col {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.demo__video {
  width: 100%;
  display: block;
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
  box-shadow: var(--shadow);
  margin-bottom: 1rem;
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

@media (min-width: 1024px) {
  #apps .features__grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  transition: border-color 0.2s, transform 0.2s;
}

.card:hover {
  border-color: rgba(249, 134, 17, 0.4);
  transform: translateY(-2px);
}

.card__icon {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}

.card__title {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.card__body {
  color: var(--color-text-muted);
  font-size: 0.92rem;
  line-height: 1.6;
}

/* ---------- How it works ---------------------------------- */
.how {
  padding: 5rem 0;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.steps {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 2rem;
  max-width: 700px;
  margin-inline: auto;
  counter-reset: steps;
}

.step {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
}

.step__number {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1.5px solid var(--color-accent);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step__content h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

.step__content p {
  color: var(--color-text-muted);
  font-size: 0.93rem;
}

.step__content code {
  font-family: var(--font-mono);
  background: var(--color-surface-2);
  padding: 0.1em 0.4em;
  border-radius: 4px;
  font-size: 0.85em;
  color: var(--color-accent-2);
}

/* ---------- Commands table -------------------------------- */
.commands {
  padding: 5rem 0;
  border-top: 1px solid var(--color-border);
}

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.tabs__input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.tabs__label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1rem;
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: rgba(255, 255, 255, 0.03);
  color: var(--color-text-muted);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  transition: transform 0.15s, opacity 0.2s, border-color 0.2s, color 0.2s;
  user-select: none;
}

.tabs__label:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

#commands-tab-system:checked + .tabs__label,
#commands-tab-browser:checked + .tabs__label {
  color: var(--color-text);
  border-color: rgba(249, 134, 17, 0.35);
  background: rgba(249, 134, 17, 0.12);
}

.tabs__panels {
  width: 100%;
}

.tabs__panel {
  display: none;
}

#commands-tab-system:checked ~ .tabs__panels .tabs__panel--system {
  display: block;
}

#commands-tab-browser:checked ~ .tabs__panels .tabs__panel--browser {
  display: block;
}

.table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-border);
}

.cmd-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.cmd-table th,
.cmd-table td {
  padding: 0.85rem 1.25rem;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

.cmd-table th {
  background: var(--color-surface);
  color: var(--color-text-muted);
  font-weight: 600;
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.cmd-table tbody tr:last-child td {
  border-bottom: none;
}

.cmd-table tbody tr:hover td {
  background: var(--color-surface);
}

.cmd-table code {
  font-family: var(--font-mono);
  color: var(--color-accent-2);
  font-size: 0.9em;
}

/* ---------- Repos ----------------------------------------- */
.repos {
  padding: 5rem 0;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.repos__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.repo-card {
  display: block;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  transition: border-color 0.2s, transform 0.2s;
}

.repo-card:hover {
  border-color: rgba(249, 134, 17, 0.5);
  transform: translateY(-2px);
}

.repo-card__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.repo-card__icon {
  width: 28px;
  height: 28px;
  color: var(--color-accent);
}

.repo-card__arrow {
  font-size: 1.1rem;
  color: var(--color-text-muted);
}

.repo-card__name {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  font-family: var(--font-mono);
}

.repo-card__desc {
  color: var(--color-text-muted);
  font-size: 0.92rem;
  margin-bottom: 1rem;
  line-height: 1.6;
}

.repo-card__tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.tag {
  background: rgba(249, 134, 17, 0.1);
  border: 1px solid rgba(249, 134, 17, 0.25);
  color: var(--color-accent);
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.2rem 0.6rem;
  border-radius: 100px;
}

/* ---------- Footer ---------------------------------------- */
.footer {
  border-top: 1px solid var(--color-border);
  padding: 2.5rem 0;
}

.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  text-align: center;
}

.footer__logo {
  font-weight: 800;
  font-size: 1.1rem;
  background: linear-gradient(135deg, var(--color-accent), var(--color-accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.footer__tagline {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.footer__link {
  color: var(--color-accent);
  font-size: 0.88rem;
  font-weight: 500;
  transition: opacity 0.2s;
}

.footer__link:hover {
  opacity: 0.75;
}

/* ---------- Responsive ------------------------------------ */
@media (max-width: 640px) {
  .nav__links a:not(.btn) {
    display: none;
  }

  .hero {
    padding: 4rem 0 3rem;
  }

  .step {
    gap: 1rem;
  }

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