/* TTP (Tera Term Pilot) LP
 * インラインスタイルを使わない前提で設計している。
 * CSP は style-src 'self' のみ許可しているため、style属性・<style>要素は禁止。
 */

:root {
  --bg: #ffffff;
  --bg-soft: #f5f7fa;
  --bg-code: #12171f;
  --fg: #161a1f;
  --fg-muted: #5b6672;
  --fg-invert: #e8eef5;
  --border: #e3e8ee;
  --border-strong: #cfd7e0;
  --accent: #0b6b7a;
  --accent-hover: #095866;
  --accent-soft: #e6f4f6;
  --ok: #17683f;
  --ok-soft: #e8f5ee;
  --ng: #a4271b;
  --ng-soft: #fdecea;
  --warn: #7a4b00;
  --warn-soft: #fdf3e2;
  --radius: 12px;
  --radius-sm: 8px;
  --max: 980px;
  --font: system-ui, -apple-system, "Segoe UI", "Hiragino Kaku Gothic ProN",
    "Noto Sans JP", Meiryo, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Cascadia Code",
    "Courier New", monospace;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.8;
  text-rendering: optimizeLegibility;
}

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

a {
  color: var(--accent);
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--accent-hover);
}

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
  border-radius: 4px;
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 20px;
}

.skip-link {
  position: absolute;
  left: -9999px;
}

.skip-link:focus {
  left: 8px;
  top: 8px;
  z-index: 100;
  background: var(--bg);
  padding: 8px 12px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
}

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 60px;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
  letter-spacing: 0.02em;
}

.brand:hover {
  color: var(--fg);
}

.brand-text {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
}

.brand small {
  font-weight: 500;
  font-size: 12px;
  color: var(--fg-muted);
  letter-spacing: 0.04em;
}

.nav {
  display: flex;
  align-items: center;
  gap: 18px;
  font-size: 14px;
  flex-wrap: wrap;
}

.nav a {
  color: var(--fg-muted);
  text-decoration: none;
}

.nav a:hover {
  color: var(--accent);
}

/* .nav a の color 指定より優先させる */
.nav a.btn,
.nav a.btn:hover {
  color: #fff;
}

/* ---------- buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: #fff;
  font-weight: 700;
  font-size: 15px;
  text-decoration: none;
  border: 1px solid var(--accent);
  transition: background 0.15s ease;
}

.btn:hover {
  background: var(--accent-hover);
  color: #fff;
}

.btn-ghost {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--border-strong);
}

.btn-ghost:hover {
  background: var(--accent-soft);
  color: var(--accent-hover);
}

.btn-sm {
  padding: 8px 14px;
  font-size: 13px;
}

/* ---------- layout ---------- */

main {
  display: block;
}

section {
  padding: 56px 0;
  border-bottom: 1px solid var(--border);
}

section:last-of-type {
  border-bottom: 0;
}

.section-soft {
  background: var(--bg-soft);
}

h1,
h2,
h3,
h4 {
  line-height: 1.4;
  margin: 0 0 16px;
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(26px, 4.4vw, 42px);
  letter-spacing: 0.005em;
}

h2 {
  font-size: clamp(21px, 2.8vw, 28px);
}

h3 {
  font-size: 18px;
}

p {
  margin: 0 0 16px;
}

.lead {
  font-size: 17px;
  color: var(--fg-muted);
}

.eyebrow {
  display: inline-block;
  margin-bottom: 12px;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.06em;
}

/* ---------- hero ---------- */

.hero {
  padding: 64px 0 56px;
  border-bottom: 1px solid var(--border);
  background:
    radial-gradient(1100px 420px at 12% -12%, #eaf6f8 0%, transparent 62%),
    var(--bg);
}

.hero h1 {
  margin-bottom: 18px;
}

.hero h1 span {
  display: block;
  color: var(--accent);
}

.hero .lead {
  max-width: 640px;
  font-size: 17px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 28px;
}

.hero-note {
  margin-top: 14px;
  font-size: 13px;
  color: var(--fg-muted);
}

.kv {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 40px;
  list-style: none;
  padding: 0;
}

.kv li {
  padding: 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
}

.kv strong {
  display: block;
  font-size: 17px;
  margin-bottom: 4px;
}

.kv span {
  font-size: 13px;
  color: var(--fg-muted);
  line-height: 1.6;
  display: block;
}

/* ---------- before / after ---------- */

.ba {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  align-items: start;
}

.panel {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg);
}

.panel-head {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  font-size: 13px;
  font-weight: 700;
  border-bottom: 1px solid var(--border);
  background: var(--bg-soft);
}

.panel-head .tag {
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 999px;
  letter-spacing: 0.04em;
}

.tag-ng {
  background: var(--ng-soft);
  color: var(--ng);
}

.tag-ok {
  background: var(--ok-soft);
  color: var(--ok);
}

.panel pre {
  margin: 0;
  padding: 16px;
  overflow-x: auto;
  background: var(--bg-code);
  color: var(--fg-invert);
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.7;
  tab-size: 2;
}

.panel pre .c {
  color: #8b9bab;
}

.panel pre .bad {
  color: #ff9d92;
  font-weight: 700;
}

.panel pre .good {
  color: #7fe0a8;
  font-weight: 700;
}

.panel-foot {
  padding: 12px 16px;
  font-size: 13px;
  color: var(--fg-muted);
  border-top: 1px solid var(--border);
}

/* ---------- cards ---------- */

.grid {
  display: grid;
  gap: 20px;
}

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

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

.card {
  padding: 22px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
}

.card h3 {
  margin-bottom: 8px;
  font-size: 17px;
}

.card p {
  margin: 0;
  font-size: 14px;
  color: var(--fg-muted);
  line-height: 1.75;
}

.card .num {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  font-weight: 700;
}

/* ---------- table ---------- */

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

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  min-width: 620px;
}

caption {
  caption-side: top;
  text-align: left;
  padding: 14px 16px 0;
  font-size: 13px;
  color: var(--fg-muted);
}

th,
td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

thead th {
  background: var(--bg-soft);
  font-size: 13px;
  white-space: nowrap;
}

tbody th {
  font-weight: 600;
  white-space: nowrap;
}

tbody tr:last-child th,
tbody tr:last-child td {
  border-bottom: 0;
}

td.mark {
  text-align: center;
  font-weight: 700;
  white-space: nowrap;
}

.m-ok {
  color: var(--ok);
}

.m-ng {
  color: var(--ng);
}

.m-half {
  color: var(--warn);
}

.m-na {
  color: var(--fg-muted);
  font-weight: 500;
}

.table-note {
  margin: 12px 0 0;
  font-size: 12.5px;
  color: var(--fg-muted);
}

/* ---------- screenshots ---------- */

.figures {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

figure {
  margin: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--bg-soft);
}

figure img {
  display: block;
  width: 100%;
}

figcaption {
  padding: 10px 14px;
  font-size: 12.5px;
  color: var(--fg-muted);
  background: var(--bg);
  border-top: 1px solid var(--border);
}

/* 1枚だけ見せたい図版（署名警告など） */
.figure-single {
  max-width: 520px;
  margin: 0 auto 24px;
}

/* ---------- steps ---------- */

ol.steps {
  list-style: none;
  counter-reset: step;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 16px;
}

ol.steps > li {
  counter-increment: step;
  position: relative;
  padding: 18px 18px 18px 58px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
}

ol.steps > li::before {
  content: counter(step);
  position: absolute;
  left: 18px;
  top: 18px;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

ol.steps h3 {
  margin: 0 0 6px;
  font-size: 16px;
}

ol.steps p {
  margin: 0;
  font-size: 14px;
  color: var(--fg-muted);
}

/* ---------- callout ---------- */

.callout {
  padding: 16px 20px;
  border-radius: var(--radius);
  border: 1px solid var(--border-strong);
  background: var(--bg-soft);
  font-size: 14px;
  line-height: 1.75;
}

.callout p:last-child {
  margin-bottom: 0;
}

.callout-warn {
  border-color: #e8cf9a;
  background: var(--warn-soft);
  color: #4d3200;
}

.callout-warn a {
  color: inherit;
}

/* ---------- faq ---------- */

.faq-list {
  display: grid;
  gap: 12px;
}

details.faq {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg);
  padding: 4px 18px;
}

details.faq summary {
  cursor: pointer;
  padding: 14px 0;
  font-weight: 700;
  font-size: 15px;
  list-style: none;
}

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

details.faq summary::before {
  content: "Q. ";
  color: var(--accent);
  font-family: var(--mono);
  font-size: 13px;
}

details.faq[open] summary {
  border-bottom: 1px solid var(--border);
}

details.faq .answer {
  padding: 14px 0;
  font-size: 14.5px;
  color: var(--fg-muted);
}

details.faq .answer p:last-child {
  margin-bottom: 0;
}

/* ---------- cta ---------- */

.cta {
  text-align: center;
  padding: 64px 0;
  background: var(--bg-soft);
  border-top: 1px solid var(--border);
}

.cta h2 {
  margin-bottom: 12px;
}

.cta .lead {
  max-width: 620px;
  margin: 0 auto 28px;
}

.cta-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---------- article (sub pages) ---------- */

.crumbs {
  font-size: 12.5px;
  color: var(--fg-muted);
  padding: 18px 0 0;
}

.crumbs ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin: 0;
  padding: 0;
}

.crumbs li::after {
  content: "/";
  margin-left: 6px;
  color: var(--border-strong);
}

.crumbs li:last-child::after {
  content: "";
}

.article {
  padding: 40px 0 64px;
}

.article h1 {
  margin-bottom: 20px;
}

.article h2 {
  margin-top: 48px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.article h2:first-of-type {
  margin-top: 32px;
  border-top: 0;
  padding-top: 0;
}

.article h3 {
  margin-top: 28px;
}

.article ul,
.article ol {
  padding-left: 1.3em;
  margin: 0 0 16px;
}

.article li {
  margin-bottom: 6px;
}

.article code {
  font-family: var(--mono);
  font-size: 0.9em;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 5px;
}

.article pre {
  margin: 0 0 20px;
  padding: 16px;
  overflow-x: auto;
  background: var(--bg-code);
  color: var(--fg-invert);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.7;
}

.article pre code {
  background: transparent;
  border: 0;
  padding: 0;
  color: inherit;
  font-size: inherit;
}

.article blockquote {
  margin: 0 0 20px;
  padding: 4px 0 4px 18px;
  border-left: 4px solid var(--border-strong);
  color: var(--fg-muted);
  font-size: 14.5px;
}

.next-links {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 48px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.next-links a {
  display: block;
  padding: 18px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--fg);
  background: var(--bg);
}

.next-links a:hover {
  border-color: var(--accent);
  color: var(--fg);
}

.next-links span {
  display: block;
  font-size: 12px;
  color: var(--fg-muted);
  margin-bottom: 4px;
}

.next-links strong {
  font-size: 15px;
  color: var(--accent);
}

.updated {
  margin-top: 40px;
  font-size: 12.5px;
  color: var(--fg-muted);
}

/* ---------- footer ---------- */

.site-footer {
  padding: 40px 0 56px;
  border-top: 1px solid var(--border);
  font-size: 12.5px;
  color: var(--fg-muted);
}

.disclaimer {
  max-width: 760px;
  line-height: 1.8;
}

.footer-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  margin: 20px 0 0;
}

.footer-meta a {
  color: var(--fg-muted);
}

/* ---------- responsive ---------- */

@media (max-width: 820px) {
  .kv,
  .grid-3,
  .grid-2,
  .ba,
  .figures,
  .next-links {
    grid-template-columns: 1fr;
  }

  section {
    padding: 44px 0;
  }

  .hero {
    padding: 44px 0 40px;
  }

  .nav {
    gap: 12px;
    font-size: 13px;
  }
}

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

  * {
    transition: none !important;
  }
}