/* VARIABLES */
:root {
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, 
               'Segoe UI', Roboto, Helvetica, Arial, sans-serif;

  --color-text: #1a1a1a;
  --color-muted: #6b7280;
  --color-primary: #4da3ff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-main);
  color: var(--color-text);
  line-height: 1.6;
  background: #ffffff;
  -webkit-font-smoothing: antialiased;
}

.hero h1 {
  font-size: 42px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 15px;
}

.hero .sub {
  font-size: 17px;
  font-weight: 400;
  color: var(--color-muted);
  opacity: 0.85;
  line-height: 1.7;
}

.card h3 {
  font-size: 18px;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
}

.card p {
  font-size: 15px;
  color: var(--color-muted);
  line-height: 1.6;
}

.card span {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
  color: var(--color-primary);
}

h1, h2, h3 {
  text-rendering: optimizeLegibility;
}


/* GLOBAL STYLES */
html {
  scroll-behavior: smooth;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Arial, sans-serif;
}

body {
  background: linear-gradient(180deg, #f5f9ff 0%, #ffffff 100%);
  color: #1a1a1a;
}

/* HEADER */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: #ffffff;
  padding: 16px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: 0 4px 20px rgba(0,0,0,0.04);
}

/* HEADER LEFT */
.header-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-img {
  width: 36px;
  height: 36px;
  object-fit: contain;
}

.logo-text {
  font-size: 20px;
  font-weight: 700;
  color: #111;
}

/* NAV */
.nav {
  display: flex;
  gap: 32px;
  align-items: center;
}

.nav a {
  position: relative;
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  color: #2c2c2c;
  padding: 6px 2px;
  transition: color 0.3s ease;
}

/* NAV POSITION RELATIVE */
/* underline */
.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 0;
  height: 3px;
  border-radius: 6px;
  background: linear-gradient(90deg, #4da3ff, #7b61ff);
  transition: width 0.35s ease;
}

/* hover */
.nav a:hover {
  color: #4da3ff;
}

.nav a:hover::after {
  width: 100%;
}

/* active */
.nav a.active {
  color: #4da3ff;
}

.nav a.active::after {
  width: 100%;
}


/* HEADER RIGHT */
.header-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

.lang-switch span {
  cursor: pointer;
  font-size: 14px;
  opacity: 0.6;
}

.lang-switch .active {
  font-weight: 600;
  opacity: 1;
}

.lang-item {
  text-decoration: none;
  color: inherit;
}


.header-cta {
  padding: 10px 18px;
  background: linear-gradient(135deg, #35d0ba, #4da3ff);
  color: #fff;
  border-radius: 999px;
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: 0.3s;
}

.header-cta:hover {
  opacity: 0.85;
  transform: translateY(-1px);
}

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

  .header {
    padding: 14px 20px;
  }
}

/* ============================= */
/* LANGUAGE SWITCH ADVANCED */
/* ============================= */

.lang-switch {
  position: relative;
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  user-select: none;
}

/* Current language */
.lang-current {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 999px;
  background: #f6f8fb;
  transition: all 0.3s ease;
}

.lang-current img {
  width: 18px;
  height: 12px;
  object-fit: cover;
  border-radius: 2px;
}

.lang-current span {
  font-size: 13px;
  font-weight: 600;
  opacity: 1;
}

/* Hover current */
.lang-current:hover {
  background: #eef2ff;
}

/* Dropdown menu */
.lang-menu {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  width: 180px;
  background: #ffffff;
  border-radius: 14px;
  box-shadow: 0 18px 40px rgba(0,0,0,0.08);
  padding: 8px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all 0.3s ease;
  z-index: 999;
}

/* Open state */
.lang-switch.open .lang-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

/* Language item */
.lang-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 10px;
  font-size: 14px;
  transition: background 0.25s ease;
}

.lang-item img {
  width: 22px;
  height: 14px;
  object-fit: cover;
  border-radius: 2px;
}

/* Hover item */
.lang-item:hover {
  background: #f2f5ff;
}

/* Active language */
.lang-item.active {
  background: linear-gradient(135deg, #4da3ff, #7b61ff);
  color: #fff;
}

.lang-item.active img {
  filter: brightness(1.1);
}

/* Hide old simple lang switch text style */
.lang-switch span {
  opacity: 1;
}

/* Mobile adjustments */
@media (max-width: 900px) {
  .lang-menu {
    right: -10px;
  }
}



/* HERO */
.hero {
  text-align: center;
  padding: 100px 20px;
  background: linear-gradient(135deg, #eef4ff 0%, #ffffff 60%);
}

.hero h1 {
  font-size: 42px;
  margin-bottom: 15px;
}

.hero .sub {
  opacity: 0.75;
  margin-bottom: 60px;
}

/* SERVICE CARDS */
.service-links {
  display: flex;
  gap: 30px;
  justify-content: center;
  flex-wrap: wrap;
}

.card {
  background: linear-gradient(180deg, #ffffff, #f6f9ff);
  padding: 35px;
  width: 290px;
  border-radius: 18px;
  text-decoration: none;
  color: #1a1a1a;
  transition: 0.35s;
  border: 1px solid #e3ebff;
  box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.card.primary {
  border: 1px solid #4da3ff;
  box-shadow: 0 15px 40px rgba(77,163,255,0.25);
}

.card:hover {
  transform: translateY(-10px);
  box-shadow: 0 20px 45px rgba(77,163,255,0.25);
}

.card h3 {
  margin-bottom: 10px;
}

.card span {
  display: inline-block;
  margin-top: 20px;
  color: #4da3ff;
  font-weight: 600;
}

/* FEATURES V2 */
/* SECTION */
.features-v2 {
  background: #f7f9fb;
  padding: 80px 20px;
}

/* HEADER */
.features-header {
  max-width: 1100px;
  margin: 0 auto 50px;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 20px;
}

.features-header h2 {
  font-size: 32px;
  line-height: 1.3;
  font-weight: 700;
  color: #0f172a;
}

.features-link {
  font-size: 15px;
  color: #2563eb;
  text-decoration: none;
  font-weight: 500;
}

.features-link:hover {
  text-decoration: underline;
}

/* GRID */
.features-grid {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

/* CARD */
.feature-card {
  background: #ffffff;
  border-radius: 18px;
  padding: 28px 26px 32px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.04);
  transition: all 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.08);
}

/* ICON */
.icon-box {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: linear-gradient(135deg, #2fd2c3, #3aa1ff);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
}

.icon-box img {
  width: 22px;
  height: 22px;
  filter: brightness(0) invert(1); /* icon trắng */
}

/* TEXT */
.feature-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: #0f172a;
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 15px;
  line-height: 1.6;
  color: #64748b;
}

/* RESPONSIVE */
@media (max-width: 900px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .features-header {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 600px) {
  .features-grid {
    grid-template-columns: 1fr;
  }

  .features-header h2 {
    font-size: 26px;
  }
}

/* ABOUT SECTION */
.about {
  padding: 100px 40px;
  background: #f8fafc;
}

.about-container {
  max-width: 1200px;
  margin: auto;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 60px;
  align-items: center;
}

/* LEFT */
.about-left h2 {
  font-size: 36px;
  margin-bottom: 20px;
}

.about-left h2 span {
  background: linear-gradient(135deg, #35d0ba, #4da3ff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.about-left p {
  color: #555;
  line-height: 1.7;
  margin-bottom: 14px;
}

.about-en {
  font-size: 14px;
  opacity: 0.85;
}

/* ACTIONS */
.about-actions {
  margin-top: 30px;
  display: flex;
  gap: 16px;
}

.btn-primary {
  padding: 12px 22px;
  background: linear-gradient(135deg, #35d0ba, #4da3ff);
  color: #fff;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 500;
}

.btn-outline {
  padding: 12px 22px;
  border: 1px solid #4da3ff;
  color: #4da3ff;
  border-radius: 999px;
  text-decoration: none;
  font-weight: 500;
}

/* RIGHT */
.about-right {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.about-card {
  background: #fff;
  padding: 30px 20px;
  border-radius: 16px;
  text-align: center;
  box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.about-card h4 {
  font-size: 28px;
  margin-bottom: 8px;
  color: #35d0ba;
}

.about-card p {
  font-size: 14px;
  color: #666;
}

/* MOBILE */
@media (max-width: 900px) {
  .about-container {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .about {
    padding: 80px 20px;
  }

  .about-right {
    grid-template-columns: 1fr;
  }
}


/* FOLLOW US SECTION */
.follow-us {
  padding: 100px 20px;
  background: linear-gradient(180deg, #ffffff 0%, #f5f9ff 100%);
}

.follow-container {
  max-width: 1200px;
  margin: auto;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 60px;
  align-items: center;
}

.follow-left h2 {
  font-size: 36px;
  margin-bottom: 15px;
}

.follow-desc {
  color: #555;
  margin-bottom: 40px;
  max-width: 500px;
}

.follow-list {
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.follow-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  background: #ffffff;
  border-radius: 14px;
  border: 1px solid #e3ebff;
  text-decoration: none;
  color: #1a1a1a;
  box-shadow: 0 8px 25px rgba(0,0,0,0.04);
  transition: 0.3s;
}

.follow-item:hover {
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(77,163,255,0.2);
}

.follow-item .icon {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4da3ff, #7b6cff);
  color: #fff;
  text-align: center;
  line-height: 34px;
  font-weight: bold;
  margin-right: 15px;
}

.follow-item .icon.yt {
  background: linear-gradient(135deg, #ff4d4d, #ff7a7a);
}

.follow-item .icon.support {
  background: linear-gradient(135deg, #2ed8b6, #6cead1);
}

.follow-item span:nth-child(2) {
  flex: 1;
  font-weight: 500;
}

.follow-item .arrow {
  color: #4da3ff;
  font-size: 18px;
}
.follow-right {
  display: flex;
  justify-content: center;
  align-items: center;
}

.illus-orbit {
  position: relative;
  width: 300px;
  height: 300px;
  animation: orbitRotate 20s linear infinite;
}

 /* ILLUSTRATION CORE */
.follow-right {
  display: flex;
  justify-content: center;
  align-items: center;
}

.illus-field {
  position: relative;
  width: 450px;
  height: 450px;
}

/* HALO ÁNH SÁNG */
.logo-halo {
  position: absolute;
  inset: 50%;
  width: 200px;
  height: 200px;
  transform: translate(-50%, -50%);
  border-radius: 50%;

  background: radial-gradient(
    circle,
    rgba(120, 160, 255, 0.35) 0%,
    rgba(120, 160, 255, 0.18) 35%,
    rgba(120, 160, 255, 0.08) 55%,
    rgba(120, 160, 255, 0.02) 70%,
    transparent 75%
  );

  filter: blur(12px);
  animation: halo-pulse 6s ease-in-out infinite;
  z-index: 1;
}

/* LOGO */
.logo-center {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 200px;
  height: auto;
  transform: translate(-50%, -50%);
  z-index: 3;
}

/* HALO THỞ NHẸ */
@keyframes halo-pulse {
  0%,100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 0.8;
  }
  50% {
    transform: translate(-50%, -50%) scale(1.08);
    opacity: 1;
  }
}

.particle {
  position: absolute;
  background: rgba(120,160,255,0.45);
  animation: blink ease-in-out infinite,
             drift ease-in-out infinite;
  pointer-events: none;
}

.particle.circle {
  border-radius: 50%;
}

.particle.square {
  border-radius: 6px;
}

/* nhấp nháy */
@keyframes blink {
  0%   { opacity: 0.15; }
  50%  { opacity: 0.9; }
  100% { opacity: 0.15; }
}

/* dao động rộng */
@keyframes drift {
  0%   { transform: translate(0,0); }
  50%  { transform: translate(60px,-60px); }
  100% { transform: translate(-60px,60px); }
}



/* FOOTER ADVANCED */
.footer-advanced {
  background: linear-gradient(180deg, #ffffff 0%, #f2f7ff 100%);
  color: #1a1a1a;
  padding: 70px 80px 30px;
  font-size: 14px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr repeat(4, 1fr);
  gap: 40px;
  border-bottom: 1px solid #e3ebff;
  padding-bottom: 45px;
}

.footer-logo .logo-text {
  font-size: 30px;
  font-weight: 800;
  letter-spacing: 2px;
  margin-bottom: 18px;
}

.footer-logo .social a {
  display: inline-block;
  margin-right: 10px;
  width: 34px;
  height: 34px;
  background: linear-gradient(135deg, #4da3ff, #7b6cff);
  color: #fff;
  text-align: center;
  line-height: 34px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  transition: 0.3s;
}

.footer-logo .social a:hover {
  transform: translateY(-3px);
  opacity: 0.9;
}

.footer-col h4 {
  font-size: 15px;
  margin-bottom: 18px;
}

.footer-col a {
  display: block;
  color: #555;
  text-decoration: none;
  margin-bottom: 12px;
  transition: 0.3s;
}

.footer-col a:hover {
  color: #4da3ff;
}

.contact {
  padding: 100px 20px;
  background: linear-gradient(135deg, #f6faff, #eef3ff);
  color: #1a1a1a;
}

.contact-container {
  max-width: 1100px;
  margin: auto;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 60px;
}

.contact-info h2 {
  font-size: 36px;
  margin-bottom: 15px;
}

.contact-sub {
  color: #555;
  margin-bottom: 30px;
  line-height: 1.6;
}

.contact-info ul {
  list-style: none;
}

.contact-info li {
  margin-bottom: 15px;
  font-size: 15px;
}

.contact-info a {
  color: #4da3ff;
  text-decoration: none;
}

.contact-info a:hover {
  text-decoration: underline;
}


/* FORM BOX */
* {
  box-sizing: border-box;
  font-family: Arial, Helvetica, sans-serif;
}

body {
  background: #f5f7fa;
}

#contactForm {
  max-width: 420px;
  margin: 40px auto;
  padding: 25px;
  background: #ffffff;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
  animation: fadeIn 0.6s ease;
}

.form-group {
  margin-bottom: 15px;
}

input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 8px;
  border: 1px solid #ddd;
  font-size: 14px;
  transition: all 0.3s ease;
}

input:focus {
  border-color: #007bff;
  box-shadow: 0 0 0 3px rgba(0,123,255,0.15);
  outline: none;
}

button {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 8px;
  background: linear-gradient(135deg, #007bff, #0056d2);
  color: #fff;
  font-size: 15px;
  cursor: pointer;
  transition: all 0.3s ease;
}

button:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0,123,255,0.3);
}

button.loading {
  opacity: 0.7;
  pointer-events: none;
}

.form-success {
  display: none;
  margin-top: 15px;
  color: #28a745;
  text-align: center;
  font-weight: bold;
  animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}


/* Box form */
.contact-box {
  background: #fff;
  padding: 35px;
  border-radius: 18px;
  box-shadow: 0 20px 40px rgba(0,0,0,0.08);
}

.contact-box h3 {
  margin-bottom: 5px;
  font-size: 22px;
}

.contact-box p {
  font-size: 14px;
  color: #666;
  margin-bottom: 20px;
}

.contact-box form input,
.contact-box form textarea {
  width: 100%;
  padding: 12px 15px;
  margin-bottom: 15px;
  border-radius: 10px;
  border: 1px solid #ddd;
  font-size: 14px;
}

.contact-box form textarea {
  resize: none;
  height: 100px;
}

.contact-box form button {
  width: 100%;
  padding: 14px;
  border: none;
  border-radius: 12px;
  background: linear-gradient(135deg, #4da3ff, #6f7bff);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: 0.3s;
}

.contact-box form button:hover {
  opacity: 0.9;
  transform: translateY(-2px);
}

/* Mobile */
@media (max-width: 900px) {
  .contact-container {
    grid-template-columns: 1fr;
  }
}


/* FOOTER BOTTOM */
.footer-bottom {
  display: flex;
  justify-content: space-between;
  padding-top: 25px;
  color: #777;
  font-size: 13px;
}

/* MOBILE */
@media (max-width: 900px) {
  .header {
    padding: 20px;
  }

  .footer-top {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 10px;
  }
}


/* ===== Scroll Reveal Base ===== */
.reveal {
  opacity: 0;
  transition: all 0.9s cubic-bezier(.22,.61,.36,1);
  will-change: transform, opacity;
}

/* Khi hiện */
.reveal.show {
  opacity: 1;
  transform: translate(0,0);
}

/* Bay từ dưới lên */
.reveal.up {
  transform: translateY(70px);
}

/* Từ trái sang */
.reveal.left {
  transform: translateX(-80px);
}

/* Từ phải sang */
.reveal.right {
  transform: translateX(80px);
}

/* Zoom nhẹ */
.reveal.zoom {
  transform: scale(0.9);
}

.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }
.delay-3 { transition-delay: 0.3s; }
.delay-4 { transition-delay: 0.4s; }
.delay-5 { transition-delay: 0.5s; }

/* ===== Shatter Text Effect ===== */
.shatter-text {
  display: inline-block;
  position: relative;
}

.shatter-text span {
  display: inline-block;
  will-change: transform, opacity;
  transition:
    transform 2.2s cubic-bezier(.22,.61,.36,1),
    opacity 1.8s ease;
}

/* ===== PHA 1: VỠ ===== */
.shatter-text.shatter-active span {
  filter: blur(1.5px);
  opacity: 0;
  transform:
    translate(var(--x), var(--y))
    rotate(var(--r))
    scale(0.85);
}

/* ===== PHA 3: GHÉP LẠI ===== */
.shatter-text.rebuild span {
  opacity: 1;
  transform:
    translate(0, 0)
    rotate(0)
    scale(1);
  transition:
    transform 2.6s cubic-bezier(.16,.84,.44,1),
    opacity 2.2s ease;
}

/* PAGE CONTENT STYLES */
.page-content {
  max-width: 920px;
  margin: 120px auto 100px;
  padding: 0 20px;
}

.page-content h1 {
  font-size: 36px;
  margin-bottom: 24px;
}

.page-content h2 {
  margin-top: 32px;
  font-size: 22px;
}

.page-content p {
  line-height: 1.7;
  color: #444;
}