:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --surface: #ffffff;
  --surface-muted: #f1f4f7;
  --text: #18202a;
  --muted: #66717f;
  --line: #dde3ea;
  --accent: #126b63;
  --accent-dark: #0f554f;
  --accent-soft: #e4f3f1;
  --danger: #b42318;
  --danger-soft: #fff1f0;
  --danger-line: #ffccc7;
  --shadow: 0 12px 32px rgba(21, 31, 44, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  line-height: 1.5;
}

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

button,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid rgba(221, 227, 234, 0.9);
  background: rgba(247, 248, 250, 0.92);
  backdrop-filter: blur(14px);
}

.nav,
main,
.site-footer {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.nav {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-size: 1rem;
  font-weight: 720;
}

.brand-mark {
  display: inline-flex;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  font-weight: 800;
}

.home-link,
.btn-secondary,
.btn-danger,
.btn-primary {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: 7px;
  font-size: 0.9rem;
  font-weight: 720;
  padding: 8px 13px;
  transition:
    background 160ms ease,
    border-color 160ms ease,
    color 160ms ease,
    transform 160ms ease;
}

.home-link,
.btn-secondary {
  border: 1px solid var(--line);
  background: var(--surface);
  color: var(--muted);
}

.home-link:hover,
.home-link:focus-visible,
.btn-secondary:hover,
.btn-secondary:focus-visible {
  border-color: #c6d1dc;
  background: var(--surface-muted);
  color: var(--text);
  outline: none;
}

main {
  padding: 54px 0 48px;
}

.intro {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(280px, 0.85fr);
  gap: 32px;
  align-items: end;
  padding-bottom: 34px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 760;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 0;
  font-size: clamp(2.2rem, 5vw, 4.6rem);
  line-height: 1;
  letter-spacing: 0;
}

.intro-text {
  max-width: 440px;
  margin: 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.tool-shell {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
  padding: 20px;
}

.tool-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 16px;
}

.tool-heading h2 {
  margin-bottom: 4px;
  font-size: 1.05rem;
}

.tool-heading p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.counter {
  border-radius: 6px;
  background: var(--accent-soft);
  color: var(--accent-dark);
  font-size: 0.78rem;
  font-weight: 760;
  padding: 5px 9px;
  white-space: nowrap;
}

.editor-wrap {
  display: grid;
  grid-template-columns: 18px minmax(0, 1fr);
  gap: 10px;
  align-items: stretch;
}

.line-markers {
  min-height: 420px;
  overflow: hidden;
  padding-top: 16px;
  pointer-events: none;
}

.line-dot {
  display: block;
  width: 7px;
  height: var(--line-block-height, 27.2px);
  position: relative;
}

.line-dot::before {
  content: "";
  position: absolute;
  top: var(--dot-top, 10px);
  left: 5px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: #a7c9c5;
}

.line-dot.is-empty::before {
  background: transparent;
}

#text-box {
  display: block;
  width: 100%;
  min-height: 420px;
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fbfcfd;
  color: var(--text);
  font-size: 1rem;
  line-height: 1.7;
  outline: none;
  padding: 16px;
  white-space: pre-wrap;
}

#text-box:focus {
  border-color: #a7c9c5;
  background: #ffffff;
  box-shadow: 0 0 0 3px rgba(18, 107, 99, 0.1);
}

#text-box::placeholder {
  color: #8a96a3;
}

.action-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 14px;
}

.left-actions,
.right-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.btn-primary {
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  border-color: var(--accent-dark);
  background: var(--accent-dark);
  outline: none;
  transform: translateY(-1px);
}

.btn-danger {
  border: 1px solid var(--danger-line);
  background: var(--danger-soft);
  color: var(--danger);
}

.btn-danger:hover,
.btn-danger:focus-visible {
  background: #ffe4e1;
  outline: none;
}

.status {
  min-height: 22px;
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
  padding: 24px 0 34px;
}

.site-footer p {
  margin-bottom: 0;
}

@media (max-width: 760px) {
  .intro {
    grid-template-columns: 1fr;
    gap: 16px;
    padding-bottom: 22px;
  }

  .tool-heading {
    display: block;
  }

  .counter {
    display: inline-flex;
    margin-top: 12px;
  }
}

@media (max-width: 620px) {
  .nav,
  main,
  .site-footer {
    width: min(100% - 28px, 1120px);
  }

  .nav {
    min-height: 62px;
  }

  .brand-name {
    display: none;
  }

  main {
    padding-top: 38px;
  }

  h1 {
    font-size: 2.45rem;
  }

  .tool-shell {
    padding: 16px;
  }

  .editor-wrap {
    grid-template-columns: 14px minmax(0, 1fr);
    gap: 8px;
  }

  .line-markers {
    min-height: 360px;
  }

  #text-box {
    min-height: 360px;
  }

  .site-footer {
    display: block;
  }

  .site-footer p + p {
    margin-top: 6px;
  }
}