@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

/* ========== CSS Custom Properties ========== */
:root {
  --color-primary: #1a2744;
  --color-accent: #3da5d9;
  --color-accent-hover: #2e8fbf;
  --color-light-bg: #f5f7fa;
  --color-white: #ffffff;
  --color-text: #333333;
  --color-text-light: #666666;
  --color-border: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.12);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --max-width: 1200px;
  --header-height: 72px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--color-text);
  background-color: var(--color-white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

img {
  max-width: 100%;
  height: auto;
}

ul {
  list-style: none;
}

/* ========== Header ========== */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: var(--header-height);
  background-color: var(--color-white);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(20px, 4vw, 48px);
  box-shadow: var(--shadow-sm);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
}

.header-left img {
  height: 44px;
  width: auto;
}

.header-left h1 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
  white-space: nowrap;
  letter-spacing: -0.02em;
}

/* Desktop Nav */
.header-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.header-nav a {
  color: var(--color-text);
  font-size: 0.9rem;
  font-weight: 500;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition);
  white-space: nowrap;
}

.header-nav a:hover {
  background-color: var(--color-light-bg);
  color: var(--color-accent);
}

.header-nav a.active {
  background-color: var(--color-primary);
  color: var(--color-white);
}

/* Language Flags */
.language-flags {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: 16px;
  padding-left: 16px;
  border-left: 1px solid var(--color-border);
}

.language-flags img {
  width: 24px;
  height: auto;
  border-radius: 2px;
  opacity: 0.7;
  cursor: default;
  transition: opacity var(--transition);
}

.language-flags img:hover {
  opacity: 1;
}

/* Hamburger Button */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
  z-index: 1100;
}

.hamburger span {
  display: block;
  width: 100%;
  height: 2.5px;
  background-color: var(--color-primary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.hamburger.open span:nth-child(1) {
  transform: translateY(7.5px) rotate(45deg);
}

.hamburger.open span:nth-child(2) {
  opacity: 0;
}

.hamburger.open span:nth-child(3) {
  transform: translateY(-7.5px) rotate(-45deg);
}

/* Mobile Nav Overlay */
.mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  right: -100%;
  width: 280px;
  height: 100vh;
  background-color: var(--color-white);
  z-index: 1050;
  padding: 100px 32px 40px;
  box-shadow: var(--shadow-lg);
  transition: right var(--transition);
  overflow-y: auto;
}

.mobile-nav.open {
  right: 0;
}

.mobile-nav a {
  display: block;
  color: var(--color-text);
  font-size: 1.05rem;
  font-weight: 500;
  padding: 14px 0;
  border-bottom: 1px solid var(--color-border);
  transition: color var(--transition), padding-left var(--transition);
}

.mobile-nav a:hover,
.mobile-nav a.active {
  color: var(--color-accent);
  padding-left: 8px;
}

.mobile-nav .mobile-flags {
  display: flex;
  gap: 12px;
  margin-top: 24px;
  padding-top: 16px;
}

.mobile-nav .mobile-flags img {
  width: 28px;
  border-radius: 2px;
  opacity: 0.7;
  cursor: default;
}

.mobile-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.4);
  z-index: 1040;
  opacity: 0;
  transition: opacity var(--transition);
}

.mobile-overlay.open {
  opacity: 1;
}

/* ========== Main Content ========== */
main {
  padding-top: var(--header-height);
}

/* ========== Hero Section ========== */
.hero-section {
  position: relative;
  width: 100%;
  min-height: 360px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-primary) 0%, #243b5e 50%, var(--color-accent) 100%);
}

.hero-section img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.25;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 60px 24px;
  max-width: var(--max-width);
}

.hero-content h2 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.hero-content p {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: rgba(255, 255, 255, 0.85);
  max-width: 640px;
  margin: 0 auto;
  font-weight: 300;
}

/* ========== Sections ========== */
.section {
  padding: 64px 24px;
  max-width: var(--max-width);
  margin: 0 auto;
}

.section-alt {
  background-color: var(--color-light-bg);
}

.section-alt .section {
  padding: 64px 24px;
}

.section h2 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.section h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-primary);
  margin-top: 32px;
  margin-bottom: 12px;
}

.section p {
  font-size: 1.05rem;
  color: var(--color-text-light);
  line-height: 1.75;
  margin-bottom: 16px;
  max-width: 800px;
}

.section ul {
  list-style: none;
  padding: 0;
  margin: 16px 0 24px;
  max-width: 800px;
}

.section ul li {
  position: relative;
  padding: 10px 0 10px 24px;
  font-size: 1.05rem;
  color: var(--color-text-light);
  line-height: 1.6;
}

.section ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 18px;
  width: 8px;
  height: 8px;
  background-color: var(--color-accent);
  border-radius: 50%;
}

.section-centered {
  text-align: center;
}

.section-centered p {
  margin-left: auto;
  margin-right: auto;
}

/* ========== Grid Cards ========== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  margin-top: 40px;
}

.grid-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  text-align: center;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition);
}

.grid-item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.grid-item h3 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 10px;
}

.grid-item p {
  font-size: 0.95rem;
  color: var(--color-text-light);
  line-height: 1.5;
}

/* ========== Hero Frames (About page) ========== */
.hero-frames {
  width: 100%;
  overflow: hidden;
  background-color: #000;
  border-radius: var(--radius-md);
  margin: 32px 0;
}

.hero-frames img {
  width: 100%;
  height: auto;
  object-fit: cover;
  display: block;
}

/* ========== FAQ Styles ========== */
.faq-search {
  margin: 0 auto;
  padding: 40px 24px 0;
  max-width: 600px;
  text-align: center;
}

.faq-search input {
  width: 100%;
  padding: 14px 20px;
  font-size: 1rem;
  font-family: 'Inter', sans-serif;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
  background: var(--color-white);
}

.faq-search input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(61, 165, 217, 0.15);
}

.faq-list {
  margin: 24px auto 0;
  max-width: 800px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 0 24px 64px;
}

.faq-item {
  background: var(--color-light-bg);
  padding: 18px 24px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
  font-weight: 500;
  color: var(--color-primary);
}

.faq-item:hover {
  background: #e3edf7;
  transform: translateX(4px);
}

/* ========== Back Button ========== */
.back-button {
  display: inline-block;
  padding: 12px 24px;
  margin-top: 24px;
  background-color: var(--color-light-bg);
  color: var(--color-primary);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: var(--radius-sm);
  transition: background var(--transition), transform var(--transition);
  box-shadow: var(--shadow-sm);
}

.back-button:hover {
  background-color: #e3edf7;
  color: var(--color-primary);
  transform: translateX(-2px);
}

/* ========== Footer ========== */
footer {
  background-color: var(--color-primary);
  color: rgba(255, 255, 255, 0.7);
  text-align: center;
  padding: 32px 24px;
  font-size: 0.875rem;
  margin-top: 64px;
}

footer strong {
  color: var(--color-white);
  font-weight: 600;
}

/* ========== Scroll Reveal ========== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ========== Responsive ========== */
@media (max-width: 900px) {
  .header-nav {
    display: none;
  }

  .language-flags {
    display: none;
  }

  .hamburger {
    display: flex;
  }

  .mobile-nav {
    display: block;
  }

  .mobile-overlay {
    display: block;
  }

  .hero-section {
    min-height: 260px;
  }

  .section {
    padding: 40px 20px;
  }

  .grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .grid-item {
    padding: 24px 20px;
  }
}

/* ========== Dark Mode Toggle Button ========== */
.dark-mode-toggle {
  background: none;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
  font-size: 1.2rem;
  color: var(--color-text);
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
}

.dark-mode-toggle:hover {
  background: var(--color-light-bg);
}

/* ========== Dark Mode ========== */
body.dark-mode {
  --color-primary: #e2e8f0;
  --color-accent: #5bbee8;
  --color-accent-hover: #7dcef0;
  --color-text: #e2e8f0;
  --color-text-light: #a0aec0;
  --color-bg: #0f172a;
  --color-white: #1e293b;
  --color-light-bg: #1e293b;
  --color-border: #334155;
}

body.dark-mode {
  background-color: #0f172a;
}

body.dark-mode header {
  background: #1e293b;
  border-bottom-color: #334155;
}

body.dark-mode .grid-item {
  background: #1e293b;
  border-color: #334155;
}

body.dark-mode .grid-item:hover {
  border-color: #5bbee8;
}

body.dark-mode footer {
  background: #0b1120;
}

body.dark-mode .hero-section {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}

body.dark-mode .section-alt {
  background: #1e293b;
}

body.dark-mode .mobile-nav {
  background: #1e293b;
}

body.dark-mode .hamburger span {
  background: #e2e8f0;
}

body.dark-mode .faq-item {
  background: #1e293b;
}

body.dark-mode .faq-item:hover {
  background: #334155;
}

body.dark-mode .faq-search input {
  background: #1e293b;
  border-color: #334155;
  color: #e2e8f0;
}

body.dark-mode .back-button {
  background: #334155;
  color: #e2e8f0;
}

body.dark-mode .back-button:hover {
  background: #475569;
}

@media (max-width: 480px) {
  .header-left h1 {
    font-size: 1.05rem;
  }

  .header-left img {
    height: 36px;
  }

  .hero-content h2 {
    font-size: 1.5rem;
  }

  .section h2 {
    font-size: 1.4rem;
  }
}