/* ============================================================
   iSSolution — Design Tokens
   ============================================================ */
:root {
  /* Color */
  --color-bg: #F7F8F5;
  --color-surface: #FFFFFF;
  --color-warm: #E8E1D3;
  --color-secondary: #AFC8D2;
  --color-primary: #6F9992;
  --color-primary-strong: #53726D;
  --color-primary-soft: #DCE9E5;
  --color-ink: #202625;
  --color-text: #202625;
  --color-text-muted: #68716F;
  --color-text-on-ink: #F7F8F5;
  --color-text-muted-on-ink: #9AA6A3;
  --color-border: #E1E4DF;
  --color-border-on-ink: #384340;

  /* Typography */
  --font-heading: 'Outfit', 'Plus Jakarta Sans', system-ui, sans-serif;
  --font-body: 'Plus Jakarta Sans', system-ui, sans-serif;

  --fs-sm: clamp(0.875rem, 0.85rem + 0.15vw, 0.95rem);
  --fs-base: clamp(1rem, 0.96rem + 0.2vw, 1.125rem);
  --fs-md: clamp(1.15rem, 1.08rem + 0.35vw, 1.375rem);
  --fs-lg: clamp(1.6rem, 1.4rem + 1vw, 2.1rem);
  --fs-xl: clamp(2.1rem, 1.6rem + 2.2vw, 3.25rem);
  --fs-2xl: clamp(2.5rem, 1.85rem + 2.8vw, 4rem);

  /* Spacing */
  --space-section: clamp(4.5rem, 9vw, 7.5rem);
  --space-lg: clamp(2rem, 4vw, 3.5rem);
  --space-md: clamp(1.25rem, 2.5vw, 2rem);
  --space-sm: 1rem;

  --container-w: 1180px;
  --container-pad: clamp(1.25rem, 5vw, 2.5rem);

  /* Radius */
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 32px;
  --radius-pill: 999px;

  /* Shadow */
  --shadow-sm: 0 2px 8px rgba(32, 38, 37, 0.06);
  --shadow-md: 0 12px 32px rgba(32, 38, 37, 0.08);
  --shadow-lg: 0 24px 64px rgba(32, 38, 37, 0.14);

  /* Motion */
  --ease-flow: cubic-bezier(0.22, 1, 0.36, 1);
  --dur-fast: 220ms;
  --dur-med: 500ms;
  --dur-slow: 900ms;
}

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

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

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-base);
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--color-text);
}

p { color: var(--color-text); }

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

ul, ol { list-style: none; padding: 0; }

button { font: inherit; background: none; border: none; cursor: pointer; color: inherit; }

/* Focus visibility */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2.5px solid var(--color-primary-strong);
  outline-offset: 3px;
  border-radius: 4px;
}
.section--ink :is(a, button):focus-visible {
  outline-color: var(--color-secondary);
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  background: var(--color-ink);
  color: var(--color-text-on-ink);
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-sm);
  z-index: 1000;
  transition: top var(--dur-fast) var(--ease-flow);
}
.skip-link:focus {
  top: 1rem;
}

.container {
  max-width: var(--container-w);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

main > section[id] {
  scroll-margin-top: 84px;
}

.section {
  padding-block: var(--space-section);
}

.section--ink {
  background: var(--color-ink);
  color: var(--color-text-on-ink);
}
.section--ink h1, .section--ink h2, .section--ink h3 { color: var(--color-text-on-ink); }
.section--ink p { color: var(--color-text-muted-on-ink); }

.section-head {
  max-width: 40rem;
  margin-bottom: var(--space-lg);
}
.section-head__heading {
  font-size: var(--fs-xl);
}
.section-head__sub {
  margin-top: 0.75rem;
  font-size: var(--fs-md);
  color: var(--color-text-muted);
}

/* ============================================================
   Buttons & Links
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--fs-base);
  border-radius: var(--radius-pill);
  padding: 0.9rem 1.75rem;
  transition: transform var(--dur-fast) var(--ease-flow), box-shadow var(--dur-fast) var(--ease-flow), background-color var(--dur-fast) var(--ease-flow);
  white-space: nowrap;
}
.btn-primary {
  background: var(--color-ink);
  color: var(--color-text-on-ink);
  box-shadow: var(--shadow-sm);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.btn-on-ink {
  background: var(--color-bg);
  color: var(--color-ink);
  box-shadow: var(--shadow-sm);
}
.btn-on-ink:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}
.btn-lg { padding: 1.05rem 2.25rem; font-size: var(--fs-md); }
.btn-sm { padding: 0.65rem 1.4rem; font-size: var(--fs-sm); }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 600;
  color: var(--color-primary-strong);
  padding-block: 0.9rem;
}
.link-arrow span {
  transition: transform var(--dur-fast) var(--ease-flow);
  display: inline-block;
}
.link-arrow:hover span { transform: translateX(4px); }

/* ============================================================
   Header / Navigation
   ============================================================ */
.site-header {
  position: fixed;
  inset-inline: 0;
  top: 0;
  z-index: 100;
  background: transparent;
  transition: background-color var(--dur-med) var(--ease-flow), box-shadow var(--dur-med) var(--ease-flow), backdrop-filter var(--dur-med) var(--ease-flow);
}
.site-header.is-scrolled {
  background: rgba(247, 248, 245, 0.85);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
}
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 1.1rem;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
}
.brand__mark {
  height: 34px;
  width: auto;
}
.brand__word {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 1.15rem;
  color: var(--color-text);
}

.nav__list {
  display: flex;
  align-items: center;
  gap: clamp(1.25rem, 2.5vw, 2.25rem);
}
.nav__link {
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  padding: 0.4rem 0.1rem;
  position: relative;
  transition: color var(--dur-fast) var(--ease-flow);
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 0; right: 100%;
  bottom: 0;
  height: 2px;
  background: var(--color-primary-strong);
  border-radius: 2px;
  transition: right var(--dur-med) var(--ease-flow);
}
.nav__link:hover,
.nav__link.is-active {
  color: var(--color-text);
}
.nav__link:hover::after,
.nav__link.is-active::after {
  right: 0;
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
}
.nav-toggle__bar {
  display: block;
  width: 22px;
  height: 2px;
  margin-inline: auto;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--dur-fast) var(--ease-flow), opacity var(--dur-fast) var(--ease-flow);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  display: none;
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  position: relative;
  padding-top: clamp(7rem, 18vw, 10rem);
  padding-bottom: clamp(3.5rem, 8vw, 5rem);
  min-height: 100svh;
  display: flex;
  align-items: center;
  background:
    radial-gradient(60% 50% at 85% 12%, var(--color-primary-soft) 0%, transparent 65%),
    radial-gradient(45% 40% at 10% 85%, var(--color-warm) 0%, transparent 70%);
}
.hero__inner {
  display: grid;
  grid-template-areas: "visual" "text";
  gap: clamp(2rem, 6vw, 3rem);
  align-items: center;
}
.hero__text { grid-area: text; text-align: center; }
.hero__visual { grid-area: visual; display: flex; justify-content: center; }

.hero__heading {
  font-size: var(--fs-2xl);
  max-width: 18ch;
  margin-inline: auto;
}
.hero__sub {
  margin-top: 1.25rem;
  font-size: var(--fs-md);
  color: var(--color-text-muted);
  max-width: 34ch;
  margin-inline: auto;
}
.hero__actions {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
}

.hero-stage {
  position: relative;
  width: 280px;
  height: 224px;
  transform: scale(0.85);
}
.hero-stage__line { position: absolute; inset: 0; width: 100%; height: 100%; }
.hero-stage__logo {
  position: absolute;
  left: 50%; top: 50%;
  transform: translate(-50%, -50%);
  width: 78%;
  height: auto;
  filter: drop-shadow(0 14px 28px rgba(32, 38, 37, 0.12));
}
.hero-stage__dot {
  position: absolute;
  left: 0; top: 0;
  width: 8px;
  height: 8px;
  margin: -4px 0 0 -4px;
  border-radius: 50%;
  background: var(--color-primary-strong);
  offset-path: path("M50 230 C 40 160, 110 100, 190 125 C 260 147, 230 205, 165 195 C 108 186, 120 110, 195 82 C 280 51, 362 95, 352 162 C 345 213, 278 244, 210 222");
  offset-rotate: 0deg;
  box-shadow: 0 0 0 6px rgba(83, 114, 109, 0.15);
}
@media (prefers-reduced-motion: no-preference) {
  .hero-stage__dot {
    animation: travel-flow 11s linear infinite;
  }
}
@keyframes travel-flow {
  0% { offset-distance: 0%; opacity: 0; }
  6% { opacity: 1; }
  94% { opacity: 1; }
  100% { offset-distance: 100%; opacity: 0; }
}

.scroll-cue {
  position: absolute;
  left: 50%;
  bottom: clamp(1.25rem, 3vw, 2rem);
  transform: translateX(-50%);
  display: none;
}
.scroll-cue__chevron {
  display: block;
  width: 12px;
  height: 12px;
  border-right: 2px solid var(--color-text-muted);
  border-bottom: 2px solid var(--color-text-muted);
  transform: rotate(45deg);
}
@media (prefers-reduced-motion: no-preference) {
  .scroll-cue { animation: cue-bob 2.4s var(--ease-flow) infinite; }
}
@keyframes cue-bob {
  0%, 100% { transform: translate(-50%, 0); }
  50% { transform: translate(-50%, 6px); }
}

/* ============================================================
   Scroll reveal
   ============================================================ */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
}
[data-reveal].is-visible {
  opacity: 1;
  transform: none;
  transition: opacity var(--dur-slow) var(--ease-flow), transform var(--dur-slow) var(--ease-flow);
}

/* ============================================================
   Philosophy
   ============================================================ */
.philosophy__intro {
  max-width: 42rem;
  margin-inline: auto;
  text-align: center;
  margin-bottom: clamp(3rem, 7vw, 5rem);
}
.philosophy__heading { font-size: var(--fs-xl); }
.philosophy__sub {
  margin-top: 1rem;
  font-size: var(--fs-md);
  color: var(--color-text-muted);
}

.flow-sequence {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
  max-width: 24rem;
  margin-inline: auto;
  position: relative;
  padding-left: 1.5rem;
  border-left: 2px dashed var(--color-border);
}
.flow-step {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.flow-step__marker {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-primary);
  flex-shrink: 0;
  margin-left: -1.55rem;
  box-shadow: 0 0 0 4px var(--color-bg);
}
.flow-step--loop .flow-step__marker { background: var(--color-primary-strong); }
.flow-step__label {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--fs-md);
}
.flow-sequence__note {
  text-align: center;
  margin-top: 2rem;
  color: var(--color-text-muted);
  font-size: var(--fs-sm);
  font-style: italic;
}

/* ============================================================
   Programs
   ============================================================ */
.program-grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: 1fr;
}
.program-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: clamp(1.75rem, 4vw, 2.5rem);
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur-med) var(--ease-flow), box-shadow var(--dur-med) var(--ease-flow);
}
.program-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}
.program-card__level {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 2.25rem;
  color: var(--color-primary-strong);
  margin-bottom: 0.75rem;
}
.program-card__title {
  font-size: var(--fs-md);
  margin-bottom: 0.5rem;
}
.program-card__desc {
  color: var(--color-text-muted);
}

/* ============================================================
   Learning Experience
   ============================================================ */
.learning-steps {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  position: relative;
}
.learning-step {
  position: relative;
  padding-left: 1.75rem;
  border-left: 2px solid var(--color-border);
}
.learning-step__number {
  display: block;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.5rem;
  color: var(--color-secondary);
  margin-bottom: 0.5rem;
}
.learning-step__title {
  font-size: var(--fs-lg);
  margin-bottom: 0.5rem;
}
.learning-step__desc {
  color: var(--color-text-muted);
  max-width: 32ch;
}

/* ============================================================
   Why iSSolution
   ============================================================ */
.why-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}
.why-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: clamp(1.5rem, 3vw, 2rem);
  transition: transform var(--dur-med) var(--ease-flow), box-shadow var(--dur-med) var(--ease-flow), border-color var(--dur-med) var(--ease-flow);
}
.why-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}
.why-card__icon {
  width: 32px;
  height: 32px;
  color: var(--color-primary-strong);
  margin-bottom: 1rem;
}
.why-card__title {
  font-size: var(--fs-md);
  margin-bottom: 0.4rem;
}
.why-card__desc {
  color: var(--color-text-muted);
}

/* ============================================================
   Mentor / About
   ============================================================ */
.mentor__inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(2rem, 6vw, 3.5rem);
  align-items: center;
}
.mentor-frame {
  aspect-ratio: 5 / 4;
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, var(--color-primary-soft) 0%, var(--color-warm) 100%);
  position: relative;
  overflow: hidden;
}
.mentor-frame__line {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}
.mentor__heading {
  font-size: var(--fs-xl);
  margin-bottom: 1.25rem;
}
.mentor__desc {
  color: var(--color-text-muted);
  font-size: var(--fs-md);
  max-width: 34ch;
}
.mentor__desc + .mentor__desc { margin-top: 1rem; }

/* ============================================================
   Final CTA
   ============================================================ */
.cta__inner {
  text-align: center;
  max-width: 38rem;
}
.cta__heading {
  font-size: var(--fs-xl);
}
.cta__sub {
  margin-top: 1rem;
  font-size: var(--fs-md);
  margin-bottom: 2rem;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer__inner {
  padding-block: var(--space-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: 1.25rem;
}
.site-footer__mark { height: 40px; width: auto; }
.site-footer__tagline {
  color: var(--color-text-muted-on-ink);
  font-family: var(--font-heading);
  font-size: var(--fs-md);
}
.site-footer__list {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  justify-content: center;
}
.site-footer__link {
  color: var(--color-text-muted-on-ink);
  font-size: var(--fs-sm);
  transition: color var(--dur-fast) var(--ease-flow);
}
.site-footer__link:hover { color: var(--color-text-on-ink); }
.site-footer__copy {
  color: var(--color-text-muted-on-ink);
  font-size: var(--fs-sm);
  padding-top: 1rem;
  border-top: 1px solid var(--color-border-on-ink);
  width: 100%;
}

/* ============================================================
   Responsive — Tablet (≥ 640px)
   ============================================================ */
@media (min-width: 640px) {
  .program-grid { grid-template-columns: repeat(2, 1fr); }
  .why-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-stage { width: 340px; height: 272px; transform: scale(1); }
}

/* ============================================================
   Responsive — Desktop (≥ 960px)
   ============================================================ */
@media (min-width: 960px) {
  .nav-toggle { display: none !important; }
  .nav { display: block; }

  .hero__inner {
    grid-template-columns: 1.05fr 1fr;
    grid-template-areas: "text visual";
    text-align: left;
  }
  .hero__text { text-align: left; }
  .hero__heading, .hero__sub { margin-inline: 0; }
  .hero__actions { flex-direction: row; align-items: center; }
  .scroll-cue { display: block; }
  .hero-stage { width: 400px; height: 320px; transform: scale(1); }

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

  .learning-steps {
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
  }
  .learning-step { border-left: none; border-top: 2px solid var(--color-border); padding-left: 0; padding-top: 1.75rem; }

  .why-grid { grid-template-columns: repeat(5, 1fr); }

  .mentor__inner { grid-template-columns: 0.85fr 1.15fr; }

  .flow-sequence {
    flex-direction: row;
    max-width: none;
    border-left: none;
    padding-left: 0;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0.5rem;
  }
  .flow-step {
    flex-direction: column;
    gap: 0.85rem;
    text-align: center;
  }
  .flow-step:nth-child(even) { margin-top: 2.25rem; }
  .flow-step__marker { margin-left: 0; }
}

@media (min-width: 1200px) {
  .hero-stage { width: 440px; height: 352px; transform: scale(1.05); }
}

/* Hide nav links on mobile (shown via mobile-menu instead) */
@media (max-width: 959px) {
  .nav { display: none; }
  .nav__cta { display: none; }
  .nav-toggle { display: flex; }

  .mobile-menu {
    position: fixed;
    inset: 0;
    top: 0;
    background: var(--color-bg);
    padding: clamp(6rem, 20vw, 8rem) var(--container-pad) 2rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: transform var(--dur-med) var(--ease-flow), opacity var(--dur-med) var(--ease-flow), visibility 0s linear var(--dur-med);
    z-index: 90;
  }
  .mobile-menu[data-state="open"] {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
    transition: transform var(--dur-med) var(--ease-flow), opacity var(--dur-med) var(--ease-flow);
  }
  .mobile-menu__list {
    display: flex;
    flex-direction: column;
    gap: 1.75rem;
  }
  .mobile-menu__link {
    font-family: var(--font-heading);
    font-size: var(--fs-xl);
    font-weight: 600;
  }
  .mobile-menu__cta {
    align-self: flex-start;
    margin-top: 2.5rem;
  }
}

/* ============================================================
   Reduced motion — kill switch
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .hero-stage__dot,
  .scroll-cue {
    display: none;
  }
  [data-reveal] {
    opacity: 1;
    transform: none;
  }
}