@font-face {
  font-family: "Proliatica";
  src: url("/assets/fonts/Proliatica.woff2") format("woff2");
  font-weight: normal;
  font-style: normal;
  font-display: swap;
}

:root {
  --color-sky-light: #e8f4f8;
  --color-sky: #a8d4eb;
  --color-sky-dark: #7ab8d4;
  --color-sky-deep: #5a9fc8;

  --color-mountain-far: #d1e3ed;
  --color-mountain-mid: #a8c4d4;
  --color-mountain-near: #6a9ab8;
  --color-mountain-close: #4a8aa8;

  --color-primary: #5a9fc8;
  --color-primary-light: #7ab8d4;
  --color-primary-dark: #4a8aa8;
  --color-primary-darker: #357a98;

  --color-white: #ffffff;
  --color-snow: #f5f8fa;
  --color-cloud: #e8f0f5;
  --color-mist: #c8d8e2;
  --color-slate: #7a8a94;
  --color-stone: #5a6870;
  --color-dark: #3a4850;
  --color-dark-deep: #1a2830;

  --color-accent: #6a9ab8;
  --color-success: #5a90a8;
  --color-warning: #c8a870;
  --color-error: #c87070;

  --surface-page: var(--color-snow);
  --surface-section-alt: var(--color-white);
  --surface-card: var(--color-white);
  --surface-raised: var(--color-snow);
  --surface-border: var(--color-mist);
  --surface-input: var(--color-cloud);

  --text-primary: var(--color-dark-deep);
  --text-secondary: var(--color-dark);
  --text-muted: var(--color-slate);

  --nav-scrolled-bg: rgba(255, 255, 255, 0.95);
  --nav-scrolled-text: var(--color-dark-deep);
  --nav-scrolled-link: var(--color-dark);
  --nav-scrolled-line: var(--color-dark);

  --mobile-menu-bg: var(--color-white);
  --mobile-menu-link: var(--color-dark);

  --font-display: 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-body: 'Segoe UI', system-ui, -apple-system, sans-serif;
  --font-mono: 'Consolas', 'Monaco', monospace;

  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 2rem;
  --text-4xl: 2.5rem;
  --text-5xl: 3.5rem;
  --text-6xl: 4.5rem;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  --container-max: 1200px;
  --container-padding: var(--space-6);

  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
  --transition-smooth: 500ms cubic-bezier(0.4, 0, 0.2, 1);

  --shadow-sm: 0 1px 2px rgba(58, 72, 80, 0.1);
  --shadow-md: 0 4px 12px rgba(58, 72, 80, 0.1);
  --shadow-lg: 0 8px 24px rgba(58, 72, 80, 0.12);
  --shadow-xl: 0 16px 48px rgba(58, 72, 80, 0.15);

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-full: 9999px;

  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-nav: 300;
  --z-modal: 400;
  --z-tooltip: 500;
}

[data-theme="dark"] {
  --color-white: #1e2c36;
  --color-snow: #16222a;
  --color-cloud: #243040;
  --color-mist: #2e3e4c;
  --color-slate: #8aabb8;
  --color-stone: #9ab4c0;
  --color-dark: #c8dce6;
  --color-dark-deep: #e4f0f6;

  --color-primary: #6ab4d8;
  --color-primary-light: #88c8e4;
  --color-primary-dark: #5aa0c4;
  --color-primary-darker: #4890b4;

  --color-warning: #d4b87a;
  --color-error: #d48888;

  --surface-page: #16222a;
  --surface-section-alt: #1e2c36;
  --surface-card: #1e2c36;
  --surface-raised: #243040;
  --surface-border: #2e3e4c;
  --surface-input: #243040;

  --text-primary: #e4f0f6;
  --text-secondary: #c8dce6;
  --text-muted: #8aabb8;

  --nav-scrolled-bg: rgba(22, 34, 42, 0.97);
  --nav-scrolled-text: #e4f0f6;
  --nav-scrolled-link: #c8dce6;
  --nav-scrolled-line: #c8dce6;

  --mobile-menu-bg: #1e2c36;
  --mobile-menu-link: #c8dce6;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.4);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--color-dark);
  background-color: var(--color-snow);
  overflow-x: hidden;
  letter-spacing: 0.01em;
  transition: background-color var(--transition-slow), color var(--transition-slow);
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.25;
  color: var(--color-dark-deep);
}

h1 {
  font-size: var(--text-5xl);
  letter-spacing: -0.03em;
}

h2 {
  font-size: var(--text-3xl);
  letter-spacing: -0.02em;
}

h3 {
  font-size: var(--text-xl);
  letter-spacing: -0.01em;
}

p {
  margin-bottom: var(--space-4);
  line-height: 1.75;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-primary-dark);
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section {
  padding: var(--space-24) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section-title {
  margin-bottom: var(--space-4);
  letter-spacing: -0.02em;
}

.section-divider {
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  margin: 0 auto;
  border-radius: var(--radius-full);
}

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-nav);
  padding: var(--space-4) 0;
  background: transparent;
  transition: background var(--transition-base), box-shadow var(--transition-base);
}

.nav.scrolled {
  background: var(--nav-scrolled-bg);
  box-shadow: var(--shadow-md);
  backdrop-filter: blur(8px);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--container-padding);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-4);
}

.nav-logo {
  display: flex;
  align-items: center;
}

.logo-text {
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 0.02em;
  transition: color var(--transition-base);
}

.nav.scrolled .logo-text {
  color: var(--nav-scrolled-text);
}

[data-theme="dark"] .logo-text {
  color: #e4f0f6;
}

[data-theme="dark"] .nav.scrolled .logo-text {
  color: var(--nav-scrolled-text);
}

.nav-menu {
  display: flex;
  gap: var(--space-8);
  list-style: none;
}

.nav-link {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-white);
  padding: var(--space-2) 0;
  position: relative;
  transition: color var(--transition-fast);
}

.nav.scrolled .nav-link {
  color: var(--nav-scrolled-link);
}

[data-theme="dark"] .nav-link {
  color: #c8dce6;
}

[data-theme="dark"] .nav.scrolled .nav-link {
  color: var(--nav-scrolled-link);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-primary);
  transition: width var(--transition-base);
}

.nav-link:hover::after {
  width: 100%;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  border: none;
  background: rgba(255, 255, 255, 0.15);
  color: var(--color-white);
  cursor: pointer;
  transition: background var(--transition-base), color var(--transition-base), transform var(--transition-fast);
  flex-shrink: 0;
}

.theme-toggle:hover {
  background: rgba(255, 255, 255, 0.25);
  transform: scale(1.1);
}

.nav.scrolled .theme-toggle {
  background: var(--color-cloud);
  color: var(--nav-scrolled-text);
}

.nav.scrolled .theme-toggle:hover {
  background: var(--color-mist);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  width: 16px;
  height: 16px;
  transition: opacity var(--transition-fast), transform var(--transition-base);
  position: absolute;
}

.theme-toggle .icon-moon {
  opacity: 0;
  transform: rotate(90deg) scale(0.6);
}

.theme-toggle .icon-sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="dark"] .theme-toggle .icon-moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

[data-theme="dark"] .theme-toggle .icon-sun {
  opacity: 0;
  transform: rotate(-90deg) scale(0.6);
}


::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--color-snow);
}

::-webkit-scrollbar-thumb {
  background: var(--color-mist);
  border-radius: var(--radius-full);
  border: 2px solid var(--color-snow);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-slate);
}

::-webkit-scrollbar-thumb:active {
  background: var(--color-primary);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.nav-toggle-line {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-white);
  transition: background var(--transition-fast), transform var(--transition-base);
}

.nav.scrolled .nav-toggle-line {
  background: var(--nav-scrolled-line);
}

.contact {
  background: linear-gradient(180deg, var(--color-white) 0%, var(--color-sky-light) 100%);
}

[data-theme="dark"] .contact {
  background: linear-gradient(180deg, var(--color-white) 0%, #1a2830 100%);
}

.contact-content {
  text-align: center;
}

.contact-text {
  font-size: var(--text-lg);
  color: var(--color-slate);
  margin-bottom: var(--space-10);
}

.contact-links {
  display: flex;
  justify-content: center;
  gap: var(--space-8);
  flex-wrap: wrap;
}

.contact-link {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-6);
  background: var(--color-white);
  border-radius: var(--radius-lg);
  color: var(--color-dark);
  box-shadow: var(--shadow-sm);
}

.contact-link:hover {
  color: var(--color-primary);
}

.contact-icon {
  width: 20px;
  height: 20px;
  color: var(--color-primary);
}

.footer {
  background: var(--color-dark-deep);
  padding: var(--space-6) 0;
}

[data-theme="dark"] .footer {
  background: #0e1820;
}

.footer-content {
  text-align: center;
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--space-3) var(--space-6);
  margin-top: var(--space-4);
}

.footer-link {
  font-size: var(--text-sm);
  color: var(--color-slate);
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--color-white);
}

.footer-logo {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-white);
  letter-spacing: 0.02em;
}

[data-theme="dark"] .footer-logo {
  color: #e4f0f6;
}

.footer-copyright {
  font-size: var(--text-xs);
  color: var(--color-slate);
  margin-bottom: 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-8);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 500;
  border-radius: var(--radius-lg);
  border: none;
  cursor: pointer;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast), background var(--transition-fast);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0);
}

.btn-icon {
  width: 18px;
  height: 18px;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  background: var(--color-primary-dark);
  color: var(--color-white);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.btn-secondary:hover {
  background: var(--color-primary);
  color: var(--color-white);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

::selection {
  background: var(--color-primary-light);
  color: var(--color-dark-deep);
}