/* ─── Font Faces ─── */

@font-face {
  font-family: 'Polin';
  src: url('fonts/polin-regular-a4b02422ae439f9f58e7.ttf') format('truetype');
  font-weight: 400;
  font-display: swap;
}

@font-face {
  font-family: 'Polin';
  src: url('fonts/polin-medium-562e4ef62794adc21baf.ttf') format('truetype');
  font-weight: 500;
  font-display: swap;
}

@font-face {
  font-family: 'Polin';
  src: url('fonts/polin-semibold-52f76f5a4f432703904e.ttf') format('truetype');
  font-weight: 600;
  font-display: swap;
}

@font-face {
  font-family: 'Polin';
  src: url('fonts/polin-bold-665beb3c77b02611d5ab.ttf') format('truetype');
  font-weight: 700;
  font-display: swap;
}

@font-face {
  font-family: 'Polin';
  src: url('fonts/polin-extrabold-cbc27543f6713a51b08c.ttf') format('truetype');
  font-weight: 800;
  font-display: swap;
}

/* ─── Reset & Variables ─── */

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

:root {
  --white: #ffffff;
  --black: #0a0a0a;
  --gray-50: #fafafa;
  --gray-100: #f0f0f0;
  --gray-200: #e4e4e4;
  --gray-400: #a0a0a0;
  --gray-500: #6e6e6e;
  --gray-600: #4a4a4a;
  --font: 'Polin', 'Heebo', sans-serif;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out: cubic-bezier(0.33, 1, 0.68, 1);
  --nav-height: 80px;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  font-weight: 400;
  color: var(--black);
  background: var(--white);
  line-height: 1.7;
  font-size: 18px;
  overflow-x: hidden;
}

::selection {
  background: var(--black);
  color: var(--white);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 48px;
}

/* ─── Navbar — Linktree Capsule Style ─── */

.navbar {
  position: fixed;
  top: 0;
  right: 0;
  left: 0;
  z-index: 1000;
  padding: 16px 24px 0;
}

.nav-pill {
  max-width: 620px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
  padding: 0 28px;
  background: var(--white);
  border-radius: 1000px;
  border: 1px solid rgba(0, 0, 0, 0.08);
  transition: background 0.4s var(--ease), border-color 0.4s var(--ease);
}

.navbar.navbar-dark .nav-pill {
  background: rgba(10, 10, 10, 0.95);
  border-color: rgba(255, 255, 255, 0.1);
}

.navbar.navbar-dark .nav-logo-img {
  filter: invert(1);
}

.navbar.navbar-dark .nav-links a {
  color: rgba(255, 255, 255, 0.6);
}

.navbar.navbar-dark .nav-links a:hover {
  color: var(--white);
}

.navbar.navbar-dark .nav-toggle span {
  background: var(--white);
}

.nav-logo {
  display: flex;
  align-items: center;
  text-decoration: none;
  flex-shrink: 0;
}

.nav-logo-img {
  height: 20px;
  width: auto;
  transition: filter 0.4s var(--ease);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
  margin: 0;
}

.nav-links a {
  text-decoration: none;
  color: var(--gray-600);
  font-size: 14px;
  font-weight: 500;
  transition: color 0.25s var(--ease);
  white-space: nowrap;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 12px;
  border-radius: 50%;
  transition: background 0.25s var(--ease);
}

.nav-toggle:hover {
  background: var(--gray-50);
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--black);
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease), background 0.4s var(--ease);
}

.nav-toggle.active span:first-child {
  transform: translateY(3.25px) rotate(45deg);
}

.nav-toggle.active span:last-child {
  transform: translateY(-3.25px) rotate(-45deg);
}

/* ─── Hero ─── */

.hero {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  padding-top: var(--nav-height);
  position: relative;
  overflow: hidden;
}

.hero-dark {
  background: var(--black);
  color: var(--white);
}

.hero-content {
  max-width: 900px;
  padding: 80px 0 120px;
}

.hero-label {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gray-400);
  margin-bottom: 32px;
}

.hero-dark .hero-label {
  color: rgba(255, 255, 255, 0.35);
}

.hero-title {
  font-size: clamp(44px, 6.5vw, 84px);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 0;
}

.hero-dark .hero-title {
  color: var(--white);
}

.hero-title-secondary {
  background: linear-gradient(135deg, var(--gray-400), var(--gray-200));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-dark .hero-title-secondary {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.4), rgba(255, 255, 255, 0.15));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-line {
  width: 64px;
  height: 2px;
  background: var(--black);
  margin: 40px 0;
}

.hero-dark .hero-line {
  background: var(--white);
}

.hero-subtitle {
  font-size: clamp(17px, 2vw, 21px);
  font-weight: 400;
  line-height: 1.85;
  color: var(--gray-500);
  max-width: 580px;
}

.hero-dark .hero-subtitle {
  color: rgba(255, 255, 255, 0.5);
}

/* ─── Falling Pattern ─── */

.falling-pattern {
  position: absolute;
  inset: 0;
  overflow: hidden;
  z-index: 0;
}

.hero .container {
  position: relative;
  z-index: 1;
}

.falling-layer {
  position: absolute;
  top: -100%;
  left: 0;
  width: 100%;
  height: 300%;
  will-change: transform;
  animation: fall-down linear infinite;
}

.falling-layer-1 {
  animation-duration: 25s;
  background-image:
    radial-gradient(2px 2px at 30px 40px, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(2px 2px at 160px 120px, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(2.5px 2.5px at 290px 200px, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 80px 260px, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(2px 2px at 220px 60px, rgba(255,255,255,0.45) 50%, transparent 100%),
    radial-gradient(2px 2px at 350px 300px, rgba(255,255,255,0.35) 50%, transparent 100%),
    radial-gradient(2.5px 2.5px at 450px 160px, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 120px 340px, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(2px 2px at 380px 80px, rgba(255,255,255,0.45) 50%, transparent 100%),
    radial-gradient(2px 2px at 500px 240px, rgba(255,255,255,0.35) 50%, transparent 100%);
  background-size: 550px 400px;
}

.falling-layer-2 {
  animation-duration: 18s;
  animation-delay: -8s;
  background-image:
    radial-gradient(3px 3px at 70px 90px, rgba(255,255,255,0.55) 50%, transparent 100%),
    radial-gradient(2px 2px at 200px 180px, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(2.5px 2.5px at 340px 50px, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(2px 2px at 130px 300px, rgba(255,255,255,0.35) 50%, transparent 100%),
    radial-gradient(3px 3px at 460px 140px, rgba(255,255,255,0.45) 50%, transparent 100%),
    radial-gradient(2px 2px at 260px 260px, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(2.5px 2.5px at 400px 340px, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(2px 2px at 50px 200px, rgba(255,255,255,0.35) 50%, transparent 100%);
  background-size: 500px 380px;
}

.falling-layer-3 {
  animation-duration: 35s;
  animation-delay: -15s;
  background-image:
    radial-gradient(1.5px 1.5px at 100px 60px, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 240px 220px, rgba(255,255,255,0.25) 50%, transparent 100%),
    radial-gradient(2px 2px at 370px 130px, rgba(255,255,255,0.35) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 180px 350px, rgba(255,255,255,0.2) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 430px 280px, rgba(255,255,255,0.25) 50%, transparent 100%),
    radial-gradient(2px 2px at 310px 40px, rgba(255,255,255,0.3) 50%, transparent 100%);
  background-size: 480px 420px;
}

@keyframes fall-down {
  from { transform: translateY(0); }
  to { transform: translateY(33.333%); }
}

.falling-blur {
  position: absolute;
  inset: 0;
  backdrop-filter: blur(1px);
  -webkit-backdrop-filter: blur(1px);
  background-image: radial-gradient(
    circle at 50% 50%,
    transparent 0,
    transparent 2px,
    rgba(10, 10, 10, 0.85) 2px
  );
  background-size: 8px 8px;
}

@media (prefers-reduced-motion: reduce) {
  .falling-layer {
    animation: none;
    top: 0;
    height: 100%;
  }
}

/* ─── Sections ─── */

.section {
  padding: 160px 0;
  position: relative;
}

.section-light {
  background: var(--gray-50);
}

.section-dark {
  background: var(--black);
  color: var(--white);
}

.section-dark + .section-dark {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.section-dark .text-block p {
  color: rgba(255, 255, 255, 0.6);
}

.section-dark .text-accent {
  color: var(--white);
}

.section-header {
  margin-bottom: 72px;
}

.section-label {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gray-400);
  margin-bottom: 20px;
}

.section-dark .section-label {
  color: rgba(255, 255, 255, 0.35);
}

.section-title {
  font-size: clamp(32px, 4.5vw, 56px);
  font-weight: 800;
  line-height: 1.12;
  letter-spacing: -0.025em;
  color: var(--black);
}

.section-tagline {
  font-size: clamp(18px, 2.2vw, 24px);
  font-weight: 400;
  color: rgba(255, 255, 255, 0.4);
  margin-top: 16px;
  letter-spacing: -0.01em;
}

.section-dark .section-title {
  color: var(--white);
}

#kartisim .section-title {
  font-size: clamp(44px, 6vw, 80px);
  letter-spacing: -0.035em;
}

.section-body {
  max-width: 680px;
}

#approach .section-body {
  max-width: none;
}

#approach .approach-intro {
  max-width: 680px;
}

/* ─── Text Blocks ─── */

.text-block p {
  color: var(--gray-500);
  margin-bottom: 28px;
  font-weight: 400;
  font-size: 18px;
  line-height: 1.9;
}

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

.text-emphasis {
  font-weight: 700;
  color: var(--black);
  font-size: 24px;
  line-height: 1.4;
}

.section-dark .text-emphasis {
  color: var(--white);
}

.text-accent {
  font-weight: 700;
  color: var(--black);
  font-size: 18px;
}

/* ─── Approach Section ─── */

.approach-intro {
  font-size: 18px;
  font-weight: 400;
  color: var(--gray-500);
  line-height: 1.9;
  max-width: 680px;
  margin-bottom: 72px;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 72px;
}

.step-card {
  padding: 40px 36px;
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 16px;
  background: var(--white);
  transition: border-color 0.4s var(--ease), box-shadow 0.4s var(--ease), transform 0.4s var(--ease);
}

.step-card:hover {
  border-color: rgba(0, 0, 0, 0.15);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.04);
  transform: translateY(-2px);
}

.step-number {
  display: block;
  font-size: 56px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--gray-100);
  margin-bottom: 24px;
  direction: ltr;
  text-align: left;
  transition: color 0.4s var(--ease);
}

.step-card:hover .step-number {
  color: var(--black);
}

.step-title {
  font-size: 19px;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--black);
  letter-spacing: -0.01em;
}

.step-desc {
  font-size: 15px;
  font-weight: 400;
  color: var(--gray-500);
  line-height: 1.8;
}

.approach-result {
  font-size: 24px;
  font-weight: 700;
  color: var(--black);
  padding-top: 32px;
  border-top: 2px solid var(--black);
  max-width: 680px;
}

/* ─── Footer ─── */

.footer {
  padding: 56px 0;
  background: var(--black);
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.footer-content {
  display: flex;
  align-items: center;
  justify-content: center;
}

.footer-text {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.3);
  font-weight: 500;
  letter-spacing: 0.02em;
}

/* ─── Reveal Animations ─── */

.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 1s var(--ease-out), transform 1s var(--ease-out);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 {
  transition-delay: 0.12s;
}

.reveal-delay-2 {
  transition-delay: 0.24s;
}

.reveal-delay-3 {
  transition-delay: 0.36s;
}

.steps-grid .step-card:nth-child(1) { transition-delay: 0s; }
.steps-grid .step-card:nth-child(2) { transition-delay: 0.1s; }
.steps-grid .step-card:nth-child(3) { transition-delay: 0.2s; }
.steps-grid .step-card:nth-child(4) { transition-delay: 0.3s; }

/* ─── Responsive ─── */

@media (max-width: 768px) {
  :root {
    --nav-height: 80px;
  }

  body {
    font-size: 16px;
  }

  .container {
    padding: 0 24px;
  }

  .navbar {
    padding: 10px 12px 0;
  }

  .nav-pill {
    height: 56px;
    padding: 0 20px;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: 0;
    left: 0;
    bottom: 0;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 36px;
    background: var(--white);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.4s var(--ease);
    z-index: -1;
  }

  .navbar.navbar-dark .nav-links {
    background: var(--black);
  }

  .nav-links.open {
    opacity: 1;
    pointer-events: all;
  }

  .nav-links a {
    font-size: 28px;
    font-weight: 700;
    color: var(--black);
  }

  .navbar.navbar-dark .nav-links a {
    color: var(--white);
  }

  .hero-content {
    padding: 40px 0 80px;
  }

  .hero-label {
    margin-bottom: 20px;
    font-size: 11px;
  }

  .hero-line {
    width: 40px;
    margin: 24px 0;
  }

  .hero-subtitle {
    font-size: 16px;
    line-height: 1.75;
  }

  .section {
    padding: 80px 0;
  }

  .section-header {
    margin-bottom: 40px;
  }

  .section-title {
    font-size: clamp(28px, 7vw, 40px);
  }

  .section-dark .section-title {
    font-size: clamp(32px, 9vw, 56px);
  }

  .section-label {
    font-size: 11px;
    margin-bottom: 14px;
  }

  .section-tagline {
    font-size: 16px;
    margin-top: 10px;
  }

  .steps-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .step-card {
    padding: 28px 24px;
  }

  .step-number {
    font-size: 40px;
    margin-bottom: 14px;
  }

  .step-title {
    font-size: 17px;
    margin-bottom: 8px;
  }

  .step-desc {
    font-size: 14px;
  }

  .approach-intro {
    font-size: 16px;
    margin-bottom: 48px;
  }

  .approach-result {
    font-size: 18px;
    padding-top: 20px;
  }

  .text-emphasis {
    font-size: 18px;
  }

  .text-block p {
    font-size: 16px;
    margin-bottom: 20px;
    text-align: right;
  }

  .approach-intro,
  .section-tagline,
  .step-desc {
    text-align: right;
  }

  .text-accent {
    font-size: 16px;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 20px;
  }

  .navbar {
    padding: 8px 8px 0;
  }

  .nav-pill {
    height: 48px;
    padding: 0 16px;
  }

  .nav-logo-img {
    height: 17px;
  }

  .hero-content {
    padding: 24px 0 56px;
  }

  .hero-title {
    font-size: clamp(36px, 10vw, 52px);
  }

  .section {
    padding: 64px 0;
  }

  .steps-grid {
    gap: 12px;
  }

  .step-card {
    padding: 24px 20px;
  }

  .step-number {
    font-size: 36px;
    margin-bottom: 12px;
  }

  .footer {
    padding: 40px 0;
  }
}