/* eOSK — marketing site (plain CSS, no build step) */

:root {
  --color-bg: #fffdf9;
  --color-text: #1c1f1a;
  --color-text-muted: #4b5147;
  --color-text-mutest: #6b7166;
  --color-border: #ece9e0;
  --color-border-strong: #e5e2d8;
  --color-card: #f9f8f3;
  --color-faq-bg: #f3f2ec;
  --color-green: #3f8f4f;
  --color-green-dark: #347a42;
  --color-green-tint: rgba(63, 143, 79, 0.1);
  --color-green-tint-strong: rgba(63, 143, 79, 0.35);
  --color-hero-panel: #eef6ee;
  --color-dark-bg: #1c1f1a;
  --color-dark-card: #2b2e28;
  --color-dark-border: #3a3d37;
  --color-dark-text-muted: #a7ab9f;
  --color-dark-text-mutest: #c9ccc4;
  --color-accent-light: #7fd394;
  --color-amber: #d0913a;
  --color-amber-dark: #a3691e;
  --font-heading: 'Fraunces', serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --max-width: 1440px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
ul { margin: 0; padding: 0; list-style: none; }
::selection { background: var(--color-green); color: #fff; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
}

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 100px;
  font-weight: 700;
  font-size: 15.5px;
  padding: 16px 28px;
  transition: background-color 0.15s ease, color 0.15s ease;
}

.btn--primary {
  background: var(--color-green);
  color: #fff;
}
.btn--primary:hover { background: var(--color-green-dark); }

.btn--secondary {
  border: 1px solid var(--color-border-strong);
  color: var(--color-text);
}
.btn--secondary:hover { background: var(--color-faq-bg); }

.btn--sm { padding: 11px 22px; font-size: 14.5px; }
.btn--block { display: block; width: 100%; text-align: center; }

/* Header / nav */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 64px;
  border-bottom: 1px solid var(--color-border);
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  flex-shrink: 0;
}

.brand__mark {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  background: var(--color-green);
  position: relative;
}

.brand__mark span {
  width: 16px;
  height: 4px;
  border-radius: 2px;
  background: var(--color-bg);
  position: absolute;
  top: 50%;
  left: 50%;
  margin: -2px 0 0 -8px;
}
.brand__mark span:first-child { transform: rotate(-28deg) translate(0, -4px); }
.brand__mark span:last-child { transform: rotate(28deg) translate(0, 4px); }

.brand__name {
  font-family: var(--font-heading);
  font-size: 23px;
  font-weight: 700;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.brand--sm { margin-bottom: 14px; }
.brand--sm .brand__mark { width: 30px; height: 30px; border-radius: 9px; }
.brand--sm .brand__mark span { width: 14px; height: 3.5px; }
.brand--sm .brand__mark span:first-child { transform: rotate(-28deg) translate(0, -3.5px); }
.brand--sm .brand__mark span:last-child { transform: rotate(28deg) translate(0, 3.5px); }
.brand--sm .brand__name { font-size: 22px; }

.nav-toggle-input { display: none; }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 34px;
  height: 34px;
  margin-left: auto;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  height: 2px;
  border-radius: 1px;
  background: var(--color-text);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
  margin-left: auto;
  font-size: 14.5px;
  font-weight: 500;
}
.nav-links a:hover { color: var(--color-green); }
.nav-links__cta { margin-left: 8px; }

/* Hero */

.hero {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
}

.hero__content {
  padding: 88px 64px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.hero__title {
  font-family: var(--font-heading);
  font-size: 60px;
  line-height: 1.02;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 28px;
  max-width: 640px;
}

.hero__lead {
  font-size: 19px;
  line-height: 1.6;
  color: var(--color-text-muted);
  margin: 0 0 40px;
  max-width: 480px;
}

.hero__actions {
  display: flex;
  gap: 14px;
  margin-bottom: 36px;
}

.hero__facts {
  display: flex;
  gap: 28px;
  color: var(--color-text-mutest);
  font-size: 13.5px;
  font-weight: 500;
}

.hero__panel {
  background: var(--color-hero-panel);
  padding: 56px 44px;
  display: flex;
  align-items: center;
}

.hero__mockup {
  background: var(--color-bg);
  border-radius: 14px;
  padding: 20px;
  width: 100%;
  box-shadow: 0 20px 45px -25px rgba(20, 30, 20, 0.25);
}

.hero__mockup-title {
  font-size: 12px;
  color: var(--color-text-mutest);
  margin-bottom: 14px;
  font-weight: 600;
}

/* Demo: mini weekly calendar (hero) */

.demo-calendar__days {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
  margin-bottom: 10px;
}
.demo-calendar__days span {
  font-size: 11px;
  color: var(--color-text-mutest);
  text-align: center;
}

.demo-calendar__slots {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 8px;
  margin-bottom: 20px;
}

.demo-calendar__slot {
  border-radius: 8px;
  padding: 8px;
  font-size: 11px;
}
.demo-calendar__slot--busy {
  background: var(--color-green-tint);
  border: 1px solid var(--color-green-tint-strong);
  color: #2f7440;
  font-weight: 600;
}
.demo-calendar__slot--free {
  background: var(--color-card);
  color: #b7bcae;
}

.hero__divider {
  height: 1px;
  background: var(--color-border);
  margin: 16px 0;
}

.hero__student {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #f9f8f3;
  border-radius: 10px;
  padding: 12px 14px;
}

.hero__student-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero__student-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: #e5e3d9;
}

.hero__student-name { font-size: 12.5px; font-weight: 600; }
.hero__student-progress-label { font-size: 11px; color: var(--color-text-mutest); }
.hero__student-percent { font-size: 11px; color: var(--color-green); font-weight: 700; }

/* Stats strip */

.stats-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--color-border);
  max-width: var(--max-width);
  margin: 56px auto 0;
  border-radius: 20px;
  overflow: hidden;
}

.stats-strip__item {
  padding: 36px 48px;
  background: var(--color-card);
}

.stats-strip__value {
  font-family: var(--font-heading);
  font-size: 30px;
  font-weight: 700;
  margin-bottom: 6px;
}

.stats-strip__label { color: var(--color-text-muted); font-size: 14.5px; }

/* Section header */

.section { padding: 110px 64px; }

.section__intro { margin-bottom: 72px; max-width: 640px; }

.section__eyebrow {
  color: var(--color-green);
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.section__title {
  font-family: var(--font-heading);
  font-size: 38px;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin: 0;
}

/* Feature rows */

.feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
  margin-bottom: 100px;
}
.feature-row:last-child { margin-bottom: 0; }

.feature-row--reverse .feature-row__demo { order: 2; }
.feature-row--reverse .feature-row__content { order: 1; }

.feature-row__icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--color-green-tint);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  margin-bottom: 20px;
}

.feature-row__title {
  font-size: 26px;
  font-weight: 700;
  margin: 0 0 14px;
  letter-spacing: -0.01em;
}

.feature-row__text {
  color: var(--color-text-muted);
  font-size: 16px;
  line-height: 1.7;
  margin: 0 0 20px;
}

.feature-row__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  color: #2a2e26;
  font-size: 15px;
}

.feature-row__demo {
  background: #fff;
  border: 1px solid var(--color-border-strong);
  border-radius: 14px;
  padding: 24px;
  box-shadow: 0 1px 3px rgba(20, 20, 10, 0.04);
}

.feature-row__demo-title {
  font-size: 12px;
  color: var(--color-text-mutest);
  margin-bottom: 14px;
}

/* Demo: instructor schedule list (feature 1) */

.demo-schedule { display: flex; flex-direction: column; gap: 8px; }

.demo-schedule__row {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--color-card);
  border-radius: 8px;
  padding: 10px 14px;
}

.demo-schedule__bar { width: 6px; height: 32px; border-radius: 3px; }
.demo-schedule__bar--confirmed { background: var(--color-green); }
.demo-schedule__bar--free { background: #d8d5c9; }
.demo-schedule__bar--pending { background: var(--color-amber); }

.demo-schedule__label { font-size: 13px; flex: 1; }
.demo-schedule__status { font-size: 11px; }
.demo-schedule__status--confirmed { color: var(--color-green); }
.demo-schedule__status--free { color: var(--color-text-mutest); }
.demo-schedule__status--pending { color: var(--color-amber-dark); }

/* Demo: chat (feature 2) */

.demo-chat { display: flex; flex-direction: column; gap: 10px; }

.demo-chat__bubble {
  max-width: 75%;
  border-radius: 12px 12px 12px 2px;
  padding: 10px 14px;
  font-size: 13.5px;
  align-self: flex-start;
  background: #f1f0e8;
}

.demo-chat__bubble--own {
  align-self: flex-end;
  background: var(--color-green);
  color: #fff;
  font-weight: 500;
  border-radius: 12px 12px 2px 12px;
}

.demo-chat__footer {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border);
  font-size: 11px;
  color: var(--color-text-mutest);
}

/* Demo: progress bar chart (feature 3) */

.demo-chart {
  display: flex;
  align-items: flex-end;
  gap: 14px;
  height: 120px;
  margin-bottom: 14px;
}

.demo-chart__bar {
  flex: 1;
  background: linear-gradient(to top, var(--color-green), rgba(63, 143, 79, 0.25));
  border-radius: 6px 6px 0 0;
}

.demo-chart__labels {
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: var(--color-text-mutest);
}

/* Demo: route map (feature 4) */

.demo-route {
  height: 180px;
  border-radius: 10px;
  background: repeating-linear-gradient(135deg, #f4f3ee, #f4f3ee 12px, #eeece3 12px, #eeece3 24px);
  position: relative;
  overflow: hidden;
}
.demo-route svg { width: 100%; height: 100%; position: absolute; inset: 0; }

.demo-route__meta {
  display: flex;
  justify-content: space-between;
  margin-top: 14px;
  font-size: 12px;
  color: var(--color-text-muted);
}

/* Demo: PKK link (feature 5) */

.demo-pkk {
  background: #fff;
  border: 1px solid var(--color-border-strong);
  border-radius: 14px;
  padding: 32px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 20px;
  box-shadow: 0 1px 3px rgba(20, 20, 10, 0.04);
}

.demo-pkk__card {
  border-radius: 12px;
  padding: 18px 20px;
  text-align: center;
  flex: 1 1 140px;
  min-width: 0;
  max-width: 180px;
}
.demo-pkk__card--source {
  background: var(--color-card);
  border: 1px solid var(--color-border);
}
.demo-pkk__card--target {
  background: var(--color-green-tint);
  border: 1px solid rgba(63, 143, 79, 0.3);
}
.demo-pkk__card-label { font-size: 11px; margin-bottom: 6px; }
.demo-pkk__card-value { font-size: 14px; font-weight: 700; }
.demo-pkk__arrow { font-size: 22px; color: var(--color-green); }

/* Benefits (dark split) */

.benefits { background: var(--color-dark-bg); color: var(--color-bg); padding: 110px 64px; }
.benefits .section__eyebrow { color: var(--color-accent-light); }

.benefits__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.benefits__card {
  background: var(--color-dark-card);
  border-radius: 18px;
  padding: 44px;
}

.benefits__card-label {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-accent-light);
  letter-spacing: 0.05em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.benefits__card-title { font-size: 23px; font-weight: 700; margin: 0 0 24px; }

.benefits__list { display: flex; flex-direction: column; gap: 18px; }
.benefits__list-item { display: flex; gap: 14px; }
.benefits__list-icon { color: var(--color-accent-light); font-size: 18px; }
.benefits__list-title { font-weight: 600; font-size: 15px; margin-bottom: 2px; }
.benefits__list-text { color: var(--color-dark-text-muted); font-size: 13.5px; }

/* Pricing */

.pricing__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.pricing__lead { color: var(--color-text-muted); font-size: 17px; line-height: 1.6; margin: 0 0 28px; max-width: 440px; }

.pricing__list { display: flex; flex-direction: column; gap: 12px; font-size: 15px; color: #2a2e26; }

.pricing__card {
  background: var(--color-bg);
  border: 1px solid var(--color-border-strong);
  border-radius: 20px;
  padding: 48px;
  box-shadow: 0 1px 3px rgba(20, 20, 10, 0.04);
}

.pricing__card-label {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-green);
  margin-bottom: 16px;
}

.pricing__price {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 4px;
}
.pricing__price-value { font-family: var(--font-heading); font-size: 52px; font-weight: 700; }
.pricing__price-period { font-size: 14px; color: var(--color-text-mutest); }

.pricing__divider { height: 1px; background: var(--color-border); margin: 28px 0; }

.pricing__card-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  font-size: 14.5px;
  color: #2a2e26;
  margin: 0 0 32px;
}

/* FAQ */

.faq { background: var(--color-faq-bg); padding: 110px 64px; }
.faq .container { max-width: 840px; }
.faq .section__intro { margin-bottom: 56px; }
.faq .section__title { font-size: 34px; }

.faq__list { display: flex; flex-direction: column; gap: 14px; }

.faq__item {
  background: var(--color-bg);
  border: 1px solid var(--color-border-strong);
  border-radius: 14px;
  padding: 26px 30px;
}

.faq__question { font-weight: 700; font-size: 16px; margin-bottom: 8px; }
.faq__answer { color: var(--color-text-muted); font-size: 14.5px; line-height: 1.6; }

/* Final CTA */

.final-cta { padding: 100px 64px; text-align: center; }
.final-cta__title { font-family: var(--font-heading); font-size: 40px; font-weight: 700; letter-spacing: -0.01em; margin: 0 0 20px; }
.final-cta__lead { color: var(--color-text-muted); font-size: 17px; margin: 0 0 36px; }
.final-cta__actions { display: flex; gap: 14px; justify-content: center; }

/* Footer */

.site-footer { background: var(--color-dark-bg); color: var(--color-bg); padding: 72px 64px 32px; }

.footer__grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--color-dark-border);
}

.footer__about { color: var(--color-dark-text-muted); font-size: 14px; line-height: 1.6; max-width: 260px; margin: 0 0 18px; }

.footer__socials { display: flex; gap: 10px; }
.footer__social {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  background: var(--color-dark-card);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
}

.footer__heading {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-accent-light);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.footer__links { display: flex; flex-direction: column; gap: 11px; font-size: 14px; color: var(--color-dark-text-mutest); }
.footer__links a:hover { color: #fff; }

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
  font-size: 13px;
  color: #7d8177;
}
.footer__bottom-links { display: flex; gap: 24px; }
.footer__bottom-links a:hover { color: #fff; }

/* =========================================================================
   Responsive
   ========================================================================= */

@media (max-width: 1080px) {
  .site-header,
  .section,
  .benefits,
  .faq,
  .final-cta,
  .site-footer {
    padding-left: 32px;
    padding-right: 32px;
  }

  .hero__content { padding: 64px 32px; }
  .hero__panel { padding: 32px; }
  .hero__title { font-size: 46px; }

  .footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px 24px;
  }
  .footer__grid > div:first-child { grid-column: 1 / -1; }
}

@media (max-width: 860px) {
  .site-header { flex-wrap: wrap; }
  .nav-toggle { display: flex; }

  .nav-links {
    flex-basis: 100%;
    flex-direction: column;
    align-items: flex-start;
    gap: 18px;
    margin-left: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.25s ease, margin-top 0.25s ease;
  }
  .nav-links__cta { margin-left: 0; }

  .nav-toggle-input:checked ~ .nav-links {
    max-height: 320px;
    margin-top: 20px;
  }

  .hero { grid-template-columns: 1fr; }
  .hero__panel { order: -1; }
  .hero__facts { flex-wrap: wrap; row-gap: 8px; }

  .stats-strip { grid-template-columns: 1fr; margin-top: 40px; }

  .feature-row,
  .feature-row--reverse {
    grid-template-columns: 1fr;
    gap: 32px;
    margin-bottom: 64px;
  }
  .feature-row--reverse .feature-row__demo,
  .feature-row--reverse .feature-row__content {
    order: initial;
  }

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

  .pricing__grid { grid-template-columns: 1fr; gap: 40px; }

  .section__title { font-size: 30px; }
}

@media (max-width: 560px) {
  .site-header,
  .section,
  .benefits,
  .faq,
  .final-cta,
  .site-footer {
    padding-left: 20px;
    padding-right: 20px;
  }

  .section,
  .benefits,
  .faq { padding-top: 64px; padding-bottom: 64px; }

  .demo-pkk { padding: 24px 16px; }
  .demo-pkk__arrow { transform: rotate(90deg); }

  .hero__content { padding: 40px 20px; }
  .hero__panel { padding: 20px; }
  .hero__title { font-size: 34px; }
  .hero__lead { font-size: 17px; }
  .hero__actions { flex-direction: column; align-items: stretch; }

  .final-cta { padding: 64px 20px; }
  .final-cta__title { font-size: 28px; }
  .final-cta__actions { flex-direction: column; }

  .stats-strip__item { padding: 28px 24px; }

  .feature-row__title { font-size: 22px; }

  .benefits__card { padding: 28px; }

  .pricing__card { padding: 32px 24px; }

  .footer__grid { grid-template-columns: 1fr; }
  .footer__grid > div:first-child { grid-column: auto; }

  .footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
}