/* ==========================================================================
   夕岚科技 - 企业官网单页样式
   设计主题：科技蓝
   ========================================================================== */

/* ---------- 设计变量 ---------- */
:root {
  --primary: #0b5fff;
  --primary-dark: #0847c0;
  --navy: #081a3d;
  --cyan: #00d4ff;
  --bg-light: #f4f8ff;
  --bg-white: #ffffff;
  --text-main: #1a2333;
  --text-sub: #5a6b85;
  --border: #e3ebf7;
  --shadow-sm: 0 4px 16px rgba(11, 95, 255, 0.08);
  --shadow-md: 0 12px 32px rgba(11, 95, 255, 0.14);
  --shadow-lg: 0 24px 56px rgba(6, 47, 138, 0.18);
  --radius: 12px;
  --radius-lg: 20px;
  --gradient: linear-gradient(135deg, #0b5fff 0%, #00d4ff 100%);
  --font: "PingFang SC", "Microsoft YaHei", "Segoe UI", Arial, sans-serif;
}

/* ---------- 基础重置 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--text-main);
  background: var(--bg-white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

ul,
ol {
  list-style: none;
}

img {
  max-width: 100%;
  display: block;
}

button {
  font-family: inherit;
  cursor: pointer;
}

.container {
  width: 100%;
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 32px;
}

section {
  scroll-margin-top: 90px;
}

/* ---------- 通用标题 ---------- */
.section {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 72px 0;
}

.section--light {
  background: #ffffff;
}

.section-head {
  text-align: center;
  margin-bottom: 56px;
}

.section-head .tag {
  display: inline-block;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
  background: rgba(11, 95, 255, 0.08);
  padding: 7px 20px;
  border-radius: 30px;
  margin-bottom: 16px;
  letter-spacing: 2px;
}

.section-head h2 {
  font-size: 38px;
  font-weight: 700;
  color: var(--navy);
  line-height: 1.25;
  position: relative;
  padding-bottom: 18px;
}

.section-head h2::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 0;
  transform: translateX(-50%);
  width: 48px;
  height: 3px;
  background: var(--primary);
  border-radius: 2px;
}

.section-head .desc {
  margin-top: 12px;
  color: var(--text-sub);
  font-size: 15px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 30px;
  border-radius: 40px;
  font-size: 15px;
  font-weight: 600;
  border: none;
  transition: all 0.3s ease;
  cursor: pointer;
}

.btn--primary {
  background: #0b5fff;
  color: #fff;
  box-shadow: 0 8px 24px rgba(11, 95, 255, 0.32);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(11, 95, 255, 0.42);
  background: #084edf;
}

.btn--ghost {
  background: transparent;
  color: #fff;
  border: 1.5px solid rgba(255, 255, 255, 0.65);
}

.btn--ghost:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: #fff;
}

.btn--outline {
  background: #ffffff;
  color: var(--primary);
  border: 1.5px solid var(--primary);
}

.btn--outline:hover {
  background: var(--primary);
  color: #ffffff;
}

/* ==========================================================================
   顶部导航
   ========================================================================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: #ffffff;
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.04);
  transition: box-shadow 0.3s ease;
}

.site-header.scrolled {
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
}

.site-header .header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 90px;
}

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

.logo img {
  height: 42px;
  width: auto;
  display: block;
}

.main-nav ul {
  display: flex;
  align-items: center;
  gap: 6px;
}

.main-nav a {
  color: #334155;
  font-size: 15px;
  padding: 10px 20px;
  border-radius: 6px;
  position: relative;
  font-weight: 500;
  transition: color 0.25s ease;
}

.main-nav a:hover,
.main-nav a.active {
  color: #0b5fff;
}

.main-nav a.active::after {
  content: "";
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: 0;
  height: 2px;
  background: #0b5fff;
  border-radius: 2px;
}

.header-cta {
  display: flex;
  align-items: center;
  gap: 16px;
}

.header-cta .btn {
  padding: 12px 28px;
  font-size: 15px;
  border-radius: 8px;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--navy);
  border-radius: 2px;
  transition: all 0.3s ease;
}

/* 移动端导航 */
@media (max-width: 960px) {
  .main-nav {
    position: fixed;
    top: 90px;
    left: 0;
    width: 100%;
    background: #ffffff;
    padding: 16px 24px 24px;
    transform: translateY(-120%);
    transition: transform 0.35s ease;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  }

  .main-nav.open {
    transform: translateY(0);
  }

  .main-nav ul {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .main-nav a {
    display: block;
    width: 100%;
    padding: 12px 8px;
    font-size: 16px;
    color: var(--text-main);
  }

  .main-nav a.active::after {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }
}

/* ==========================================================================
   页脚
   ========================================================================== */
.site-footer {
  background: #0a1120;
  color: rgba(255, 255, 255, 0.7);
}

.footer-main {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.5fr;
  gap: 48px;
  padding: 80px 0 60px;
}

.footer-logo {
  margin-bottom: 18px;
}

.footer-logo img {
  height: 42px;
  width: auto;
  display: block;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 20px;
}

.footer-social {
  display: flex;
  gap: 12px;
}

.footer-social a {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  transition: all 0.3s ease;
}

.footer-social a:hover {
  background: var(--primary);
  color: #ffffff;
}

.footer-links h4,
.footer-subscribe h4 {
  font-size: 16px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 20px;
}

.footer-links ul li {
  margin-bottom: 12px;
}

.footer-links ul li a {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.78);
  transition: color 0.3s ease;
  position: relative;
  padding-left: 14px;
}

.footer-links ul li a::before {
  content: ">";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 12px;
  color: currentColor;
}

.footer-links ul li a:hover {
  color: var(--cyan);
}

.footer-subscribe p {
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 16px;
}

.subscribe-form {
  display: flex;
  margin-bottom: 12px;
}

.subscribe-form input {
  flex: 1;
  padding: 12px 16px;
  font-size: 14px;
  color: var(--text-main);
  background: #ffffff;
  border: none;
  border-radius: 8px 0 0 8px;
  outline: none;
}

.subscribe-form input::placeholder {
  color: #aab3c2;
}

.subscribe-form button {
  width: 48px;
  border: none;
  background: var(--primary);
  color: #ffffff;
  font-size: 16px;
  border-radius: 0 8px 8px 0;
  cursor: pointer;
  transition: background 0.3s ease;
}

.subscribe-form button:hover {
  background: var(--primary-dark);
}

.privacy-note {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding: 24px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
}

.footer-legal {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-legal a {
  color: rgba(255, 255, 255, 0.55);
  transition: color 0.3s ease;
}

.footer-legal a:hover {
  color: var(--cyan);
}

@media (max-width: 900px) {
  .footer-main {
    grid-template-columns: 1fr 1fr;
    gap: 40px 24px;
    padding: 56px 0 40px;
  }
}

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

  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

/* ==========================================================================
   Hero（首页）
   ========================================================================== */
.hero {
  background: linear-gradient(135deg, #f7fbff 0%, #ffffff 50%, #f5faff 100%);
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: 120px 0 80px;
  position: relative;
  overflow: hidden;
}

.hero-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

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

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  color: var(--primary);
  background: rgba(11, 95, 255, 0.08);
  border: 1px solid rgba(11, 95, 255, 0.2);
  padding: 7px 20px;
  border-radius: 30px;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: 64px;
  line-height: 1.15;
  font-weight: 800;
  margin-bottom: 26px;
  color: var(--navy);
  letter-spacing: -1.5px;
}

.hero h1 .gradient-text {
  background: linear-gradient(90deg, var(--primary), var(--cyan));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-text > p {
  font-size: 19px;
  color: var(--text-sub);
  margin-bottom: 44px;
  line-height: 1.8;
  max-width: 560px;
}

.hero-actions {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 52px;
}

.hero-actions .btn {
  padding: 15px 32px;
  border-radius: 10px;
  font-size: 16px;
}

.hero-actions .btn--primary span {
  margin-left: 4px;
}

.hero-actions .btn--outline {
  gap: 10px;
}

.hero-actions .play-icon {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary);
  color: #ffffff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
}

.hero-stats {
  display: flex;
  gap: 56px;
  flex-wrap: wrap;
}

.hero-stats .stat h3 {
  font-size: 42px;
  font-weight: 800;
  color: var(--primary);
  line-height: 1;
}

.hero-stats .stat p {
  font-size: 15px;
  color: var(--text-sub);
  margin: 8px 0 0;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  height: 540px;
  object-fit: cover;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

@media (max-width: 960px) {
  .hero-content {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 40px;
  }

  .hero-text > p {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .hero-visual img {
    height: 320px;
  }
}

@media (max-width: 640px) {
  .hero h1 {
    font-size: 36px;
  }

  .hero-stats {
    gap: 28px;
  }
}

/* ---------- 动画 ---------- */
@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ==========================================================================
   服务卡片
   ========================================================================== */
.service-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.service-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: all 0.35s ease;
  position: relative;
  overflow: hidden;
}

.service-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient);
  opacity: 0;
  transition: opacity 0.35s ease;
}

.service-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.service-card:hover::before {
  opacity: 1;
}

.service-card .icon-wrap {
  width: 60px;
  height: 60px;
  border-radius: 10px;
  background: rgba(11, 95, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}

.service-card .icon-wrap img {
  width: 28px;
  height: 28px;
}

.service-card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 10px;
}

.service-card p {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.8;
  margin-bottom: 18px;
}

.service-card .learn-more {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 14px;
  font-weight: 500;
  color: var(--primary);
  text-decoration: none;
  transition: gap 0.3s ease;
}

.service-card .learn-more:hover {
  gap: 8px;
}

@media (max-width: 900px) {
  .service-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .service-grid {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   关于我们
   ========================================================================== */
.about-wrap {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 56px;
  align-items: center;
}

.about-media {
  position: relative;
}

.about-media img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  width: 100%;
  height: 420px;
  object-fit: cover;
}

.about-experience {
  position: absolute;
  left: 24px;
  bottom: -28px;
  display: flex;
  align-items: center;
  gap: 12px;
  background: #ffffff;
  padding: 20px 28px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
}

.about-experience strong {
  font-size: 36px;
  font-weight: 800;
  color: var(--primary);
  line-height: 1;
}

.about-experience span {
  font-size: 14px;
  color: var(--text-sub);
}

.about-content h2 {
  font-size: 32px;
  font-weight: 700;
  color: var(--navy);
  line-height: 1.3;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 16px;
}

.about-content h2::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 48px;
  height: 3px;
  background: var(--primary);
  border-radius: 2px;
}

.about-desc {
  color: var(--text-sub);
  font-size: 15px;
  line-height: 1.9;
  margin-bottom: 28px;
}

.about-features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px 20px;
  margin-bottom: 32px;
}

.feature-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.feature-icon {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
  border-radius: 50%;
  background: var(--primary);
  color: #ffffff;
  font-size: 13px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-top: 2px;
}

.feature-item h4 {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 6px;
}

.feature-item p {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.6;
}

.about-content .btn {
  border-radius: 8px;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 600;
}

@media (max-width: 900px) {
  .about-wrap {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about-media img {
    height: 280px;
  }

  .about-experience {
    left: 16px;
    bottom: -24px;
    padding: 16px 22px;
  }

  .about-experience strong {
    font-size: 30px;
  }

  .about-features {
    grid-template-columns: 1fr;
    gap: 18px;
  }
}

/* ==========================================================================
   客户案例
   ========================================================================== */
.case-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.case-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 14px;
  overflow: hidden;
  transition: all 0.35s ease;
}

.case-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-6px);
}

.case-card .case-media {
  height: 220px;
  overflow: hidden;
  position: relative;
  border-radius: 14px 14px 0 0;
  margin: -1px -1px 0;
}

.case-card .case-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
  border-radius: 14px 14px 0 0;
}

.case-card:hover .case-media img {
  transform: scale(1.06);
}

.case-card .case-tag {
  position: absolute;
  top: 16px;
  left: 16px;
  display: inline-block;
  font-size: 12px;
  font-weight: 500;
  padding: 5px 14px;
  border-radius: 30px;
  color: #ffffff;
}

.case-tag.tag-blue { background: #0b5fff; }
.case-tag.tag-cyan { background: #06b6d4; }
.case-tag.tag-orange { background: #f59e0b; }
.case-tag.tag-purple { background: #8b5cf6; }
.case-tag.tag-green { background: #10b981; }

.case-card .case-body {
  padding: 22px 24px 24px;
}

.case-card .case-body h3 {
  font-size: 18px;
  color: var(--navy);
  margin-bottom: 10px;
}

.case-card .case-body p {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.8;
  margin-bottom: 14px;
}

.case-card .case-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 14px;
  font-weight: 500;
  color: var(--primary);
  text-decoration: none;
  transition: gap 0.3s ease;
}

.case-card .case-link:hover {
  gap: 8px;
}

.cases-section .section-foot,
#cases .section-foot {
  text-align: center;
  margin-top: 48px;
}

#cases .section-foot .btn {
  padding: 12px 28px;
  border-radius: 8px;
  font-size: 15px;
  border: 1.5px solid var(--border);
  color: var(--primary);
}

#cases .section-foot .btn:hover {
  border-color: var(--primary);
  background: rgba(11, 95, 255, 0.04);
}

@media (max-width: 900px) {
  .case-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 560px) {
  .case-grid {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   联系我们
   ========================================================================== */
.contact-wrap {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 30px;
  align-items: stretch;
  max-width: 1100px;
  margin: 0 auto;
}

.contact-card {
  background: #f5f7fa;
  border-radius: var(--radius-lg);
  padding: 32px;
  height: 100%;
}

.contact-card .card-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 24px;
}

.contact-right {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

/* 表单 */
.contact-form .form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.contact-form .form-group {
  margin-bottom: 20px;
}

.contact-form label {
  display: block;
  font-size: 14px;
  color: var(--text-main);
  margin-bottom: 8px;
}

.contact-form input,
.contact-form textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: 14px;
  color: var(--text-main);
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
  color: #aab3c2;
}

.contact-form input:focus,
.contact-form textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(11, 95, 255, 0.1);
}

.contact-form textarea {
  resize: vertical;
  min-height: 120px;
}

.btn--send {
  width: 100%;
  padding: 14px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius);
}

/* 联系信息 */
.contact-list li {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 20px;
}

.contact-list li:last-child {
  margin-bottom: 0;
}

.contact-icon {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  border-radius: 50%;
  background: rgba(11, 95, 255, 0.1);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
}

.contact-detail b {
  display: block;
  font-size: 15px;
  color: var(--navy);
  margin-bottom: 4px;
}

.contact-detail span {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.6;
}

/* 联系二维码 */
.qr-list-item {
  display: flex;
  gap: 16px;
  margin-top: 8px;
  align-items: flex-start;
}

.qr-list-item .qr-item {
  flex: 1;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.qr-list-item .qr-item .qr-box {
  background: #ffffff;
  border-radius: 10px;
  padding: 5px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 10px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100px;
  height: 100px;
}

.qr-list-item .qr-item .qr-box img {
  max-width: 90px;
  max-height: 90px;
  width: auto;
  height: auto;
  border-radius: 6px;
  border: 1px solid var(--border);
  display: block;
}

.qr-list-item .qr-item > span {
  font-size: 13px;
  color: var(--text-sub);
}

.contact-divider {
  height: 1px;
  background: var(--border);
  margin: 4px 0 12px;
  list-style: none;
}

@media (max-width: 900px) {
  .contact-wrap {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .contact-form .form-row {
    grid-template-columns: 1fr;
  }
}

/* ==========================================================================
   返回顶部按钮
   ========================================================================== */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 48px;
  height: 48px;
  border: none;
  border-radius: 50%;
  background: var(--primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: 0 6px 20px rgba(11, 95, 255, 0.3);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all 0.35s ease;
  z-index: 999;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: #084edf;
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(11, 95, 255, 0.4);
}

@media (max-width: 560px) {
  .back-to-top {
    right: 16px;
    bottom: 16px;
    width: 44px;
    height: 44px;
    line-height: 44px;
    font-size: 18px;
  }
}