/* ================================================================
   longhorizons — longhorizons.in
   Rikpunj Kumar | Strategic Advisor + Writer
   Stack: Vanilla HTML / CSS / JS
   Direction B — Steel: Deep Slate (#101418) + Steel Blue (#4A8FA8)
   Typography: IBM Plex Serif / Sans / Mono
   ================================================================ */

/* ─── IBM Plex Font System ─── */
@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Serif:ital,wght@0,300;0,400;0,500;1,300;1,400;1,500&family=IBM+Plex+Sans:wght@300;400;500;600&family=IBM+Plex+Mono:wght@400;500&display=swap');

/* ─── CSS Custom Properties (Design Tokens) ─── */
:root {
  /* Dark mode — default | Direction B: Deep Slate + Steel Blue */
  --bg-primary:    #101418;
  --bg-secondary:  #151A1F;
  --bg-card:       #1A2028;
  --border:        #232C36;
  --border-hover:  #2E3D4C;
  --text-primary:  #E8EDF2;
  --text-secondary:#8A9AAC;
  --text-muted:    #4A5C6C;
  --accent:        #4A8FA8;
  --accent-light:  #6AAEC8;
  --accent-dim:    #2A5F78;
  --nav-bg:        rgba(16, 20, 24, 0.92);
  --shadow:        0 8px 40px rgba(0,0,0,0.45);
}

[data-theme="light"] {
  --bg-primary:    #FFFFFF;
  --bg-secondary:  #F2F6F8;
  --bg-card:       #E6EEF2;
  --border:        #C8D8E4;
  --border-hover:  #A8BFD0;
  --text-primary:  #0F1C26;
  --text-secondary:#4A6070;
  --text-muted:    #8A9FAC;
  --accent:        #2A6882;
  --accent-light:  #4A8FA8;
  --accent-dim:    #2A6882;
  --nav-bg:        rgba(255, 255, 255, 0.92);
  --shadow:        0 8px 40px rgba(0,0,0,0.08);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'IBM Plex Sans', sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.35s ease, color 0.35s ease;
}

img {
  max-width: 100%;
  display: block;
}

/* ─── Typography ─── */
h1, h2, h3, h4, h5 {
  font-family: 'IBM Plex Serif', serif;
  font-weight: 400;
  line-height: 1.12;
  letter-spacing: -0.015em;
  color: var(--text-primary);
}

h1 { font-size: clamp(3rem, 7vw, 6rem); }
h2 { font-size: clamp(2.2rem, 4.5vw, 3.6rem); }
h3 { font-size: clamp(1.5rem, 2.5vw, 2.2rem); }
h4 { font-size: clamp(1.1rem, 1.8vw, 1.5rem); }

p {
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-secondary);
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

strong { color: var(--text-primary); font-weight: 500; }

/* ─── Layout ─── */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 2.5rem;
}

.container--narrow {
  max-width: 740px;
  margin: 0 auto;
  padding: 0 2.5rem;
}

/* ─── Navigation ─── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 200;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
  transition: background 0.35s ease, border-color 0.35s ease;
}

.nav__inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 2.5rem;
  height: 70px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo { text-decoration: none; display: flex; flex-direction: column; gap: 2px; }

.nav__logo-name {
  font-family: 'IBM Plex Serif', serif;
  font-size: 1.2rem;
  font-weight: 400;
  color: var(--accent);
  letter-spacing: 0.06em;
  line-height: 1;
  text-transform: none;
  font-variant: normal;
}

/* ─── Brand name — lowercase, no transforms ─── */
.brand-sc {
  font-family: 'IBM Plex Serif', serif;
  font-variant: normal;
  text-transform: none;
  letter-spacing: 0.06em;
}

.nav__logo-sub {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.58rem;
  font-weight: 400;
  color: var(--text-muted);
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.nav__right {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 2.2rem;
  list-style: none;
}

.nav__links a {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  transition: color 0.2s ease;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--accent);
  border-bottom-color: var(--accent-dim);
}

/* Theme toggle */
.theme-toggle {
  background: none;
  border: 1px solid var(--border);
  cursor: pointer;
  padding: 0.35rem 0.9rem;
  border-radius: 2rem;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.66rem;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.theme-toggle:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
}

/* Hamburger */
.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 1.5px;
  background: var(--text-secondary);
  transition: all 0.25s ease;
}

/* ─── Sections ─── */
.section {
  padding: 8rem 0;
}

.section--sm {
  padding: 5rem 0;
}

/* ─── Accent / Label elements ─── */
.label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  display: block;
  margin-bottom: 1.4rem;
}

.accent-line {
  width: 44px;
  height: 2px;
  background: var(--accent);
  margin-bottom: 1.8rem;
}

hr.divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 5rem 0;
}

/* ─── Buttons ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.85rem 2rem;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  border: 1px solid;
  cursor: pointer;
  transition: all 0.25s ease;
  white-space: nowrap;
}

.btn--gold {
  background: var(--accent);
  border-color: var(--accent);
  color: #0A1218;
}
.btn--gold:hover {
  background: var(--accent-light);
  border-color: var(--accent-light);
  color: #0A1218;
}

.btn--outline {
  background: transparent;
  border-color: var(--border);
  color: var(--text-secondary);
}
.btn--outline:hover {
  border-color: var(--accent-dim);
  color: var(--accent);
}

/* ─── Cards ─── */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 2.2rem;
  transition: border-color 0.25s ease, transform 0.25s ease, box-shadow 0.25s ease;
}

.card:hover {
  border-color: var(--accent-dim);
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}

/* ─── Blog post card ─── */
.post-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 2rem 2.2rem;
  transition: border-color 0.25s ease, transform 0.25s ease;
  display: flex;
  flex-direction: column;
  gap: 0.9rem;
}

.post-card:hover {
  border-color: var(--accent-dim);
  transform: translateY(-3px);
}

.post-card__tag {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.58rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
}

.post-card__title {
  font-family: 'IBM Plex Serif', serif;
  font-size: 1.5rem;
  font-weight: 400;
  line-height: 1.25;
  color: var(--text-primary);
  transition: color 0.2s ease;
}

.post-card:hover .post-card__title { color: var(--accent-light); }

.post-card__excerpt {
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--text-secondary);
}

.post-card__meta {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.64rem;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  display: flex;
  gap: 1.2rem;
  align-items: center;
  margin-top: auto;
  padding-top: 0.5rem;
  border-top: 1px solid var(--border);
}

/* ─── Grid layouts ─── */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

/* ─── Credentials grid ─── */
.cred-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  margin-top: 3rem;
}

.cred-item {
  background: var(--bg-card);
  padding: 1.8rem 2rem;
}

.cred-item__label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.58rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.cred-item__value {
  font-family: 'IBM Plex Serif', serif;
  font-size: 1.05rem;
  color: var(--text-primary);
  line-height: 1.35;
}

.cred-item__sub {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

/* ─── Photo placeholder ─── */
.photo-placeholder {
  width: 100%;
  aspect-ratio: 4/5;
  background: var(--bg-card);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 0.6rem;
}

.photo-placeholder__initials {
  font-family: 'IBM Plex Serif', serif;
  font-size: 4rem;
  font-weight: 300;
  color: var(--accent-dim);
  line-height: 1;
}

.photo-placeholder__note {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.62rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* Photo when actual image is used */
.about-photo {
  width: 100%;
  aspect-ratio: 4/5;
  object-fit: cover;
  object-position: center top;
  border: 1px solid var(--border);
}

/* ─── Hero ─── */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 70px;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background:
    radial-gradient(ellipse 60% 50% at 80% 50%, rgba(74,143,168,0.06) 0%, transparent 70%),
    radial-gradient(ellipse 40% 40% at 20% 80%, rgba(10,18,24,0.8) 0%, transparent 100%);
  pointer-events: none;
}

/* Light mode: remove the dark vignette so text stays legible on white */
[data-theme="light"] .hero::before {
  background:
    radial-gradient(ellipse 60% 50% at 80% 50%, rgba(42,104,130,0.06) 0%, transparent 70%),
    radial-gradient(ellipse 50% 50% at 20% 80%, rgba(230,238,242,0.5) 0%, transparent 100%);
}

.hero__inner {
  position: relative;
  z-index: 1;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 2.5rem;
  width: 100%;
}

.hero__eyebrow {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.64rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 2rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.hero__eyebrow::before {
  content: '';
  display: block;
  width: 36px;
  height: 1px;
  background: var(--accent);
}

.hero__headline {
  font-family: 'IBM Plex Serif', serif;
  font-size: clamp(3.5rem, 8vw, 7.5rem);
  font-weight: 300;
  line-height: 1.0;
  letter-spacing: -0.02em;
  max-width: 800px;
  margin-bottom: 1.5rem;
}

.hero__headline em {
  font-style: italic;
  color: var(--accent);
}

.hero__sub {
  max-width: 520px;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-secondary);
  margin-bottom: 3rem;
}

.hero__ctas {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero__scroll {
  position: absolute;
  bottom: 3rem;
  left: 2.5rem;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.58rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.hero__scroll::before {
  content: '';
  display: block;
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, transparent, var(--accent-dim));
}

/* ─── Manifesto strip ─── */
.manifesto {
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 5rem 0;
  background: var(--bg-secondary);
}

.manifesto__text {
  font-family: 'IBM Plex Serif', serif;
  font-size: clamp(1.4rem, 3vw, 2.2rem);
  font-weight: 300;
  line-height: 1.55;
  color: var(--text-primary);
  max-width: 820px;
}

.manifesto__text em {
  color: var(--accent);
  font-style: italic;
}

/* ─── About two-column ─── */
.about-cols {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 6rem;
  align-items: start;
}

/* ─── Contact form ─── */
.form-group {
  margin-bottom: 1.6rem;
}

.form-group label {
  display: block;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.64rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-primary);
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 0.95rem;
  padding: 0.9rem 1.2rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  outline: none;
  -webkit-appearance: none;
  appearance: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-muted);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--accent-dim);
  box-shadow: 0 0 0 3px rgba(74,143,168,0.10);
}

.form-group textarea {
  min-height: 160px;
  resize: vertical;
}

.form-group select {
  cursor: pointer;
}

.form-note {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  padding-left: 1rem;
  border-left: 2px solid var(--accent-dim);
  font-style: italic;
}

/* ─── Footer ─── */
.footer {
  border-top: 1px solid var(--border);
  padding: 3rem 0;
}

.footer__inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 2.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer__left {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.7;
}

.footer__left strong {
  color: var(--text-secondary);
  font-weight: 400;
}

.footer__right {
  display: flex;
  gap: 1.8rem;
}

.footer__right a {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.64rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
}

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

/* ─── Fade-in scroll animation ─── */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.75s ease, transform 0.75s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in--d1 { transition-delay: 0.1s; }
.fade-in--d2 { transition-delay: 0.2s; }
.fade-in--d3 { transition-delay: 0.3s; }
.fade-in--d4 { transition-delay: 0.45s; }

/* ─── Page hero (inner pages) ─── */
.page-hero {
  padding-top: 140px;
  padding-bottom: 5rem;
  border-bottom: 1px solid var(--border);
}

.page-hero__label {
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.5rem;
  display: block;
}

.page-hero__title {
  font-family: 'IBM Plex Serif', serif;
  font-size: clamp(2.8rem, 6vw, 5rem);
  font-weight: 300;
  line-height: 1.08;
  margin-bottom: 1.5rem;
}

.page-hero__sub {
  max-width: 540px;
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ─── Blog page specific ─── */
.blog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.blog-filter {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 3.5rem;
}

.filter-btn {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.64rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.4rem 1rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.filter-btn:hover,
.filter-btn.active {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(74,143,168,0.08);
}

/* ─── Subscribe strip ─── */
.subscribe-strip {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  padding: 4rem;
  text-align: center;
  margin-top: 5rem;
}

.subscribe-strip h3 {
  margin-bottom: 0.8rem;
}

.subscribe-strip p {
  max-width: 480px;
  margin: 0 auto 2rem;
  font-size: 0.9rem;
}

.subscribe-form {
  display: flex;
  gap: 0;
  max-width: 420px;
  margin: 0 auto;
}

.subscribe-form input {
  flex: 1;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-right: none;
  color: var(--text-primary);
  font-family: 'IBM Plex Sans', sans-serif;
  font-size: 0.9rem;
  padding: 0.85rem 1.2rem;
  outline: none;
}

.subscribe-form input:focus {
  border-color: var(--accent-dim);
}

.subscribe-form button {
  background: var(--accent);
  border: 1px solid var(--accent);
  color: #0A1218;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0 1.5rem;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.subscribe-form button:hover {
  background: var(--accent-light);
  border-color: var(--accent-light);
}

/* ─── Utility ─── */
.text-gold { color: var(--accent); }
.text-muted { color: var(--text-muted); font-size: 0.82rem; }
.mt-sm { margin-top: 1rem; }
.mt-md { margin-top: 2rem; }
.mt-lg { margin-top: 3.5rem; }

/* ─── Responsive ─── */
@media (max-width: 900px) {
  .grid-3, .blog-grid { grid-template-columns: repeat(2, 1fr); }
  .about-cols { grid-template-columns: 1fr; gap: 3.5rem; }
  .cred-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .grid-3, .blog-grid, .grid-2 { grid-template-columns: 1fr; }
  .container, .container--narrow { padding: 0 1.5rem; }
  .nav__inner { padding: 0 1.5rem; }
  .hero__inner { padding: 0 1.5rem; }

  .nav__links {
    display: none;
    position: absolute;
    top: 70px;
    left: 0; right: 0;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 1.8rem 1.5rem;
    gap: 1.4rem;
    align-items: flex-start;
  }

  .nav__links.open { display: flex; }
  .nav__hamburger { display: flex; }

  .section { padding: 5rem 0; }
  .subscribe-strip { padding: 2.5rem 1.5rem; }
  .subscribe-form { flex-direction: column; }
  .subscribe-form input { border-right: 1px solid var(--border); border-bottom: none; }

  .hero__headline { font-size: clamp(2.8rem, 11vw, 4rem); }
  .footer__inner { flex-direction: column; }

  .hero__scroll { display: none; }
}