body {
  margin: 0;
  font-family: Arial, sans-serif;
  line-height: 1.6;
  background-color: #d4eaf8;
}

.container {
  max-width: 1500px; 
  margin: 0 auto;    
  padding: 0 15px;   
}

/* ===== HEADER ===== */
.header {
  background-image: url('images/header_top.jpg');
  background-size: cover;
  background-repeat: no-repeat;
  background-position: center;
  padding: 5px 20px;
}

.header-top {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 40px;
}

.header-left {
  margin-top: 10px;
  display: flex;
  align-items: center;
  gap: 15px;
}

.header-info-group {
  display: flex;
  flex-direction: column; 
  justify-content: center;
  align-items: flex-start; 
  gap: 6px; 
}

.header-block {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo img {
  height: 50px;
}

.slogan img {
  height: 50px;
}

.header-item {
  display: flex;
  align-items: center;
  font-size: 15px;
  line-height: 1;
  padding: 0;
  margin-top: 3px;
}

.header-item a {
  text-decoration: none;
  color: black;
}

@keyframes iconBounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-3px);
  }
}

.icon {
  width: 18px;
  height: 18px;
  margin-right: 6px;
  animation: iconBounce 1.5s infinite;
  display: inline-block;
  vertical-align: middle;
}

/* ===== LINE WIDTH ===== */
.blue-divider {
  height: 4px; 
  background-color: #8fc0db; 
  width: 100%;
  margin: 0 auto;
}

/* ===== BANNER ===== */
.banner-full {
  width: 100vw;           
  max-width: 100%;        
  height: 20%;
  overflow: hidden;
}

.banner-image {
  width: 100%;
  height: auto;
  display: block;
}

.banner-img {
  text-align: center;
}

.banner-img img {
  width: 150px;
  height: 150px;
  object-fit: contain;
  margin-bottom: 10px;
}
/* ===== WHY ===== */
.why{
  text-align: center;
   background-color: white;
   padding: 40px;
}
.why h1, 
.why p {
  margin: 0;
}

 /* ===== section-divider ===== */ /* thanh ngang nằm dưới */
.section-divider-why {
  width: 180px;
  height: 7px;
  background-color: #90dbff;
  margin: 0 auto 20px auto;
  border-radius: 2px;
}

.companys {
  display: flex;
  justify-content: space-around;
  margin-top: 10px;
}

.company {
  width: 30%;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}
/* ===== GIỚI THIỆU ===== */
.hero-signature {
  display: flex;
  align-items: center;
  justify-content: center; 
  background: linear-gradient(#030435, #090734, #0f3b99) ;
  padding: 80px 40px;
  flex-wrap: wrap;
  gap: 60px; 
  text-align: left; 
}

.hero-content {
  max-width: 800px;
  color: white;
  display: flex;
  flex-direction: column;
  align-items: center; 
  text-align: center; 
}

.hero-content h1 {
  font-size: 48px;
  line-height: 1.4;
  color: #ffffff;
  margin-bottom: 10px;
}

.hero-content h1 span {
  color: #90dbff;
  font-weight: bold;
}

.hero-content p {
  font-size: 18px;
  color: #e0e0e0;
  margin: 20px 0 30px;
}

.btn-primary {
  background-color: #90dbff;
  color: #000f62;
  padding: 14px 28px;
  border-radius: 10px;
  text-decoration: none;
  font-weight: bold;
  transition: background-color 0.3s ease, color 0.3s ease;
  font-size: 16px;
  display: inline-block;
}

.btn-primary:hover {
  background-color: #ffffff;
  color: #000f62;
}

.hero-visual img:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 24px rgba(0,0,0,0.12);
}

.hero-visual img {
  height: 100%;
  width: 300px;
  border-radius: 12px;
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.3);
}

/* ===== GIỚI THIỆU Chat Bảo Mật ===== */
.digital-signature-feature {
  background-color: white;
  padding: 30px 20px;
  text-align: center;
}

.digital-signature-feature h2 {
  font-size: 38px;
  margin-bottom: 40px;
  color: black;
}

.ds-block {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 80px;
  margin: 0 40px;
  flex-wrap: wrap;
}

.ds-image {
  flex: 1;
  max-width: 600px;
  min-width: 300px;
  height: 100%;
}

.ds-image img {
  width: 50%;
  height: auto;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.ds-text {
  flex: 1;
  min-width: 300px;
  text-align: left;
  color: black;
}

.ds-text h3 {
  font-size: 24px;
  margin-bottom: 10px;
  color: black;
}

.ds-text p {
  text-align: justify;
  font-size: 16px;
  line-height: 1.6;
  margin-bottom: 10px;
  text-indent: 30px; /* thụt đầu dòng 30px */
}

/* ===== LỢI ÍCH & LÝ DO ===== */
.why-choose {
  text-align: center;
  background-color: white;
  padding: 40px;
}

.why-choose h1{
  margin: 0;
}
.why-choose p {
  margin-top: 0;
  text-align: justify;
   text-indent: 30px; /* thụt đầu dòng 30px */
}

.reasons {
  display: flex;
  justify-content: space-around;
  margin-top: 10px;
}

.reason {
  width: 30%;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* ===== section-divider ===== */ /* thanh ngang nằm dưới */
.section-divider {
  width: 140px;
  height: 7px;
  background-color: #90dbff;
  margin: 0 auto 20px auto;
  border-radius: 2px;
}

/* ===== section-divider ===== */ /* thanh ngang nằm dưới */
.section-divider-benefit {
  width: 130px;
  height: 7px;
  background-color: #90dbff;
  margin: 0 auto 20px auto;
  border-radius: 2px;
}

/* ===== Tính năng ===== */
.signature-process {
  background-color: white;
  padding: 30px 20px;
  text-align: center;
}

.right {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 80px;
  margin: 0 40px;
  flex-wrap: wrap;
}

.product-box {
   flex: 1;
  max-width: 600px;
  min-width: 300px;
  height: 100%;
}

.product-box img {
 width: 400px;
  height: auto;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.version {
  text-align: center;
  font-size: 28px;
  font-weight: bold;
  color: #2a75a9;
}

.highlight {
  background-color: #2a75a9;
  color: #fff;
  text-align: center;
  padding: 8px;
  font-weight: bold;
  margin: 15px 0;
}

.features {
  background-color: white;
  padding: 15px;
  border-radius: 8px;
}

.features h3 {
  margin-top: 0;
  margin-bottom: 10px;
  font-size: 20px;
}

.features ul {
  margin: 0;
  padding-left: 20px;
}

.features ul li {
  text-align: left;
  margin-bottom: 8px;
  line-height: 1.5;
}

/* ===== các tính năng ===== */
.chat-feature {
  background-color: white;
  padding: 30px 20px;
  text-align: center;
}

.chat-feature h1 {
  margin: 0;
}

/* ===== section-divider ===== */ /* thanh ngang nằm dưới */
.section-divider-feature {
  width: 250px;
  height: 7px;
  background-color: #90dbff;
  margin: 0 auto 20px auto;
  border-radius: 2px;
}

.chat-block {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 80px;
  margin: 0 40px;
  flex-wrap: wrap;
}

.mess-block{
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 80px;
  margin: 0 40px;
  flex-wrap: wrap;
}

.chat-image {
  flex: 1;
  max-width: 600px;
  min-width: 300px;
  height: 100%;
}

.mess-image {
  flex: 1;
  max-width: 600px;
  min-width: 300px;
  height: 100%;
}

.chat-image img {
  width: 50%;
  height: auto;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.mess-image img {
  width: 50%;
  height: auto;
  border-radius: 16px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.chat-text {
  flex: 1;
  min-width: 300px;
  text-align: left;
  color: black;
}

.mess-text {
  flex: 1;
  min-width: 300px;
  text-align: left;
  color: black;
}

.chat-text h3 {
  font-size: 24px;
  margin-bottom: 10px;
  color: black;
}

.mess-text h3 {
  font-size: 24px;
  margin-bottom: 10px;
  color: black;
}

.chat-text ul {
  margin: 0;
  padding-left: 20px;
}

.mess-text ul {
  margin: 0;
  padding-left: 20px;
}

.chat-text ul li {
  text-align: left;
  margin-bottom: 8px;
  line-height: 1.5;
}

.mess-text ul li {
  text-align: left;
  margin-bottom: 8px;
  line-height: 1.5;
}

/* ===== ĐĂNG KÝ ===== */
.trial-register {
  background-color: white;
  padding: auto;
}

.register-wrapper {
  display: flex;
  justify-content: center;
  align-items: stretch;
  max-width: 1300px;
  margin: 0 auto;
  background-color: white;
  border-radius: 10px;
  overflow: hidden;
}

.register-image {
  flex: 0.9;
  background-color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px;
}

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

.register-form {
  flex: 1.1;
  padding: 40px 50px;
  display: flex;
  flex-direction: column;
  align-items: center; 
}

.register-form form {
  width: 100%;
  max-width: 600px;
}

.register-form h2 {
  color: #0066cc;
  margin-bottom: 5px;
}

.register-form p {
  font-size: 14px;
  color: #555;
  margin-bottom: 20px;
}

.form-row {
  display: flex;
  gap: 20px;
}

.form-group {
  flex: 1;
  margin-bottom: 15px;
  display: flex;
  flex-direction: column;
}

.form-group label {
  font-weight: bold;
  margin-bottom: 5px;
  font-size: 14px;
}

.form-group input,
.form-group select {
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 6px;
}

.btn-submit {
  margin-top: 10px;
  padding: 12px;
  background-color: #c1e2ff;
  color: #000;
  font-weight: bold;
  width: 100%;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

.btn-submit:hover {
  background-color: #aad7ff;
}

.input-error {
    border: 2px solid red;
    background-color: #ffe6e6;
}

/* ===== FOOTER CAROUSEL ===== */
.footer-carousel {
  background: white;
  padding-top: 30px 20px;    /* sửa: padding-top thành padding đều */
  position: relative;
  max-width: 1500px;
  margin: 0 auto;
}

.carousel-title {
  font-weight: bold;
  text-align: center;
  font-size: 22px;            /* sửa: 20px → 22px (nổi bật hơn) */
  margin-bottom: 30px;        /* sửa: 40px → 30px (hợp lý hơn) */
  color: #000000;
}

.owl-carousel .item {
  background: #fff;
  padding: 15px;
  border-radius: 6px;
  box-shadow: 0 0 6px rgba(0,0,0,0.1);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center; 
  justify-content: center; 
  transition: transform 0.3s ease;   /* thêm hiệu ứng hover */
}

.owl-carousel .item:hover {
  transform: translateY(-5px);
}

.owl-carousel .item img {
  width: 120px;   /* sửa: thay vì width: 50% !important */
  height: auto;
  margin-bottom: 10px;
}

.carousel-item .product-title {
  margin: 10px 0 5px;
  font-weight: bold;
}

.carousel-item .price {
  color: red;
  font-weight: bold;
  font-size: 14px;
}

.product-title {
  font-weight: bold;
 font-size: 16px;   /* sửa: 18px → 16px (cân đối với ảnh) */
  color: rgb(0, 0, 0);
  text-align: center;
  margin-top: 4px;
}

.product-price {
  font-weight: bold;
  font-size: 15px;   /* sửa: 16px → 15px */
  color: #c00;
  text-align: center;
  margin-top: 4px;
}

.carousel-item .package {
  background: #0b3b5b;
  color: white;
  padding: 2px 6px;
  border-radius: 3px;
  font-weight: bold;
  font-size: 12px;
}

.carousel-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 24px;
  background: #fff;
  border: none;
  cursor: pointer;
  z-index: 1;
  padding: 6px 12px;
  border-radius: 50%;
  box-shadow: 0 0 4px rgba(0,0,0,0.2);
}

.carousel-btn.left {
  left: 0;
}

.carousel-btn.right {
  right: 0;
}

.item {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center; 
  justify-content: center; 
}

/* ===== WHY CHOOSE ===== */
.hero-section {
  position: relative;
  height: 400px;
  overflow: hidden;
}

.background-video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover; 
  z-index: 0;
}

.overlay {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 100%;
  color: white;
  text-align: center;
  background: rgba(0, 0, 0, 0.4); 
  padding: 0 auto;
}
/* ===== FOOTER ===== */
.footer {
  color: black;
  font-family: Arial, sans-serif;
  position: relative; 
  overflow: hidden; 
}

.footer-container {
  display: flex;
  flex-wrap: nowrap;
  justify-content: space-between;
  max-width: 1200px;
  margin: 0 auto;
  position: relative;
  z-index: 1;
}

.footer-col {
  flex: 1 1 180px;
  margin: 10px;
}

.footer-col h3 {
  font-size: 14px;
  margin-bottom: 10px;
  border-bottom: 1px solid rgb(255, 255, 255);
  padding-bottom: 5px;
  text-transform: uppercase;
}

.icon-heading {
  display: flex;
  align-items: center; 
  gap: 6px;
  font-weight: bold;
  border-bottom: 2px solid black;
  padding-bottom: 5px;
}

.icon-heading span {
  color: white;
}

.icon-title {
  width: 20px;
  height: 20px;
}

.footer-col ul {
  list-style: none;
  padding: 0;
  text-align: left; /* tất cả nội dung trong ul căn trái */
}

.footer-col ul li {
  margin-bottom: 8px;
  font-size: 18px;
  color: rgb(255, 255, 255);
  line-height: 1.6; /* cho đều khoảng cách giữa các dòng */
}

.footer-link {
  color: rgb(255, 255, 255);
  text-decoration: none;
  transition: color 0.3s ease, text-decoration 0.3s ease;
}

.footer-link:hover {
  color: #007BFF; 
}

.contact p {
  font-size: 20px;
  line-height: 1.6;
  color: rgb(255, 255, 255);
  text-align: left; /* tất cả nội dung trong ul căn trái */
}

.logoSOF {
  width: 100%;
  max-width: 150px;
  height: auto;
  margin:  0 auto 10px auto;
  display: block;
}

.slogan {
  font-style: italic;
  color: rgb(255, 255, 255);
}

.map-section iframe {
  width: 100% !important;
  max-width: 100%;
  height: 350px;
  border: 0;
  display: block;
}

/* ===== COPYRIGHT ===== */
.copyright {
  padding: 20px;
  background-color: #3087fe;
  color: white;
  text-align: center;
  font-size: 13px;
  font-weight: bold;
}

/* ===== BACK TO TOP BUTTON ===== */
#backtop {
  width: 50px;
  height: 50px;
  background-color: #9cd9ee;
  color: #fff;
  display: none;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  position: fixed;
  bottom: 40px;
  right: 20px;
  font-size: 1.5rem;
  cursor: pointer;
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
  transition: background-color 0.3s ease, transform 0.3s ease;
}

#backtop:hover {
  background-color: #2196f3;
  transform: translateY(-3px);
}

/* ===== ICON ZALO, PHONE ===== */
@keyframes bouncePulse {
0% {
transform: scale(1) translateY(0);
box-shadow: 0 0 0 0 rgba(33, 150, 243, 0.6);
}
25% {
transform: scale(1.1) translateY(-10px);
box-shadow: 0 0 10px 5px rgba(33, 150, 243, 0.3);
}
50% {
transform: scale(1) translateY(0);
box-shadow: 0 0 0 0 rgba(33, 150, 243, 0.6);
}
75% {
transform: scale(1.05) translateY(-5px);
box-shadow: 0 0 6px 3px rgba(33, 150, 243, 0.4);
}
100% {
transform: scale(1) translateY(0);
box-shadow: 0 0 0 0 rgba(33, 150, 243, 0.6);
}
}
.contact-buttons {
position: fixed;
top: 50%;
right: 20px; /* Chuyển qua bên phải */
transform: translateY(-50%);
display: flex;
flex-direction: column;
gap: 15px;
z-index: 1000;
}
.contact-icon {
width: 56px;
height: 56px;
border-radius: 50%;
display: flex;
justify-content: center;
align-items: center;
animation: bouncePulse 1.4s infinite ease-in-out;
box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
transition: transform 0.3s ease;
}
.contact-icon:hover {
transform: scale(1.2);
}
.contact-icon img {
width: 30px;
height: 30px;
object-fit: contain;
pointer-events: none;
filter: brightness(0) invert(1);
}
.zalo-icon {
background-color: #2196f3;
}
.phone-icon {
background-color: #2196f3;
}

/* Tablet (<=1024px) */
@media (max-width: 1024px) {
  .header-top {
    flex-direction: column;
    gap: 10px;
  }

  .companys,
  .reasons {
    flex-direction: column;
    align-items: center;
  }

  .company,
  .reason {
    width: 90%;
    margin-bottom: 20px;
  }

  .ds-block {
    flex-direction: column;
    gap: 30px;
  }

  .ds-image img {
    width: 80%;
  }

  .left img {
    width: 100%;
  }
}

/* Mobile (<=768px) */
@media (max-width: 768px) {
  .hero-content h1 {
    font-size: 28px;
  }

  .hero-content p {
    font-size: 16px;
  }

  .btn-primary {
    padding: 10px 20px;
    font-size: 14px;
  }

  .register-wrapper {
    flex-direction: column;
  }

  .register-image {
    padding: 20px;
  }

  .form-row {
    flex-direction: column;
    gap: 10px;
  }

  .carousel-item {
    min-width: 140px;
  }

  .map-section iframe {
    width: 100%;
    height: 250px;
  }
}

/* Mobile nhỏ (<=480px) */
@media (max-width: 480px) {
  .logo img,
  .slogan img {
    height: 36px;
  }

  .overlay h1 {
    font-size: 1.6rem;
  }

  .overlay p {
    font-size: 0.9rem;
  }

  .hero-visual img {
    width: 100%;
    max-width: 280px;
  }

  .product-box img {
    width: 260px;
  }

  .version {
    font-size: 20px;
  }
}

/* Tablet and smaller thêm vô thứ 7 */
@media (max-width: 768px) {
  .footer-container {
    flex-direction: column;
    align-items: center;
    padding: 20px;
  }

  .footer-col {
    width: 100%;
    max-width: 100%;
    padding: 10px 20px;
    text-align: center;
  }

  .footer-col ul {
    text-align: left;
  }

  .footer-col ul li {
    font-size: 14px;
  }

  .contact p {
    text-align: center;
  }

  .logoSOF {
    margin: 0 auto 10px auto;
  }

  .map-section iframe {
    height: 200px;
  }
}

/* Mobile nhỏ (<=480px) */
@media (max-width: 480px) {
  .footer-col h3 {
    font-size: 13px;
  }

  .footer-col ul li {
    font-size: 12px;
  }

  .contact p {
    font-size: 16px;
  }

  .copyright {
    font-size: 11px;
    padding: 10px;
  }
}

/* === Responsive thêm ngày 9/9 === */
@media (max-width: 1024px) {
  .carousel-title {
    font-size: 20px;
  }
  .owl-carousel .item img {
    width: 100px;
  }
}

@media (max-width: 768px) {
  .carousel-title {
    font-size: 18px;
  }
  .owl-carousel .item {
    padding: 10px;
  }
  .owl-carousel .item img {
    width: 80px;
  }
  .product-title {
    font-size: 14px;
  }
  .product-price {
    font-size: 13px;
  }
}

@media (max-width: 480px) {
  .carousel-title {
    font-size: 16px;
    margin-bottom: 20px;
  }
  .owl-carousel .item {
    padding: 8px;
  }
  .owl-carousel .item img {
    width: 70px;
  }
  .product-title {
    font-size: 13px;
  }
  .product-price {
    font-size: 12px;
  }
}