/* ========================================
   ErosAI · 爱欧罗思 — 主页样式
   ======================================== */

/* ===== CSS Variables ===== */
:root {
  /* Brand Colors */
  --c-primary: #6C5CE7;
  --c-primary-dark: #5849C4;
  --c-primary-light: #8B7FF0;
  --c-secondary: #E84393;
  --c-secondary-dark: #C73B7E;
  --c-accent: #FDCB6E;
  --c-accent-dark: #E8B84D;

  /* Neutral Colors */
  --c-dark: #0F0F1E;
  --c-darker: #08081A;
  --c-dark-2: #1A1A2E;
  --c-dark-3: #252540;
  --c-light: #F8F9FF;
  --c-light-2: #F0F2F8;
  --c-white: #FFFFFF;
  --c-gray: #6B7280;
  --c-gray-light: #9CA3AF;
  --c-gray-lighter: #E5E7EB;
  --c-border: rgba(0, 0, 0, 0.06);

  /* Gradients */
  --grad-primary: linear-gradient(135deg, #6C5CE7 0%, #E84393 100%);
  --grad-primary-soft: linear-gradient(135deg, rgba(108, 92, 231, 0.1) 0%, rgba(232, 67, 147, 0.1) 100%);
  --grad-hero: radial-gradient(ellipse at top, #1A1A3E 0%, #0F0F1E 50%, #08081A 100%);
  --grad-cta: linear-gradient(135deg, #6C5CE7 0%, #9B59B6 50%, #E84393 100%);
  --grad-text: linear-gradient(135deg, #6C5CE7 0%, #E84393 100%);
  --grad-text-light: linear-gradient(135deg, #A78BFA 0%, #F472B6 100%);

  /* Typography */
  --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Consolas', monospace;

  /* Layout */
  --container-max: 1200px;
  --section-padding: 100px 0;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 24px;
  --radius-xl: 32px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.10);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.15);
  --shadow-xl: 0 30px 80px rgba(0, 0, 0, 0.20);
  --shadow-glow: 0 0 40px rgba(108, 92, 231, 0.25);
  --shadow-glow-pink: 0 0 40px rgba(232, 67, 147, 0.20);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.06);

  /* Transitions */
  --t-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --t-normal: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --t-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  --t-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--c-dark);
  background: var(--c-white);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

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

.section {
  padding: var(--section-padding);
}

/* ===== Section Header ===== */
.section-tag {
  display: inline-block;
  padding: 6px 16px;
  background: var(--grad-primary-soft);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 600;
  color: var(--c-primary);
  letter-spacing: 0.5px;
  margin-bottom: 16px;
}

.section-tag.center {
  display: block;
  width: fit-content;
  margin-left: auto;
  margin-right: auto;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  line-height: 1.3;
  letter-spacing: -0.5px;
  color: var(--c-dark);
  margin-bottom: 16px;
}

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

.section-desc {
  font-size: 1.05rem;
  color: var(--c-gray);
  line-height: 1.8;
  max-width: 600px;
}

.section-desc.center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

/* ===== Gradient Text ===== */
.gradient-text {
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.gradient-text-light {
  background: var(--grad-text-light);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.3px;
  transition: var(--t-normal);
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn-sm {
  padding: 8px 20px;
  font-size: 14px;
}

.btn-lg {
  padding: 15px 36px;
  font-size: 16px;
}

.btn-primary {
  background: var(--grad-primary);
  color: var(--c-white);
  box-shadow: 0 4px 20px rgba(108, 92, 231, 0.35);
}

.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #5849C4 0%, #C73B7E 100%);
  opacity: 0;
  transition: var(--t-normal);
  z-index: 0;
}

.btn-primary > * {
  position: relative;
  z-index: 1;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(108, 92, 231, 0.45);
}

.btn-primary:hover::before {
  opacity: 1;
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.08);
  color: var(--c-white);
  border: 1px solid rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(10px);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.4);
  transform: translateY(-2px);
}

.btn-outline-light {
  background: transparent;
  color: var(--c-white);
  border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-outline-light:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.6);
  transform: translateY(-2px);
}

/* ===== Navigation ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 18px 0;
  transition: var(--t-normal);
}

.navbar.scrolled {
  padding: 12px 0;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: var(--shadow-sm);
  border-bottom: 1px solid var(--c-border);
}

.nav-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.5px;
}

.logo-icon {
  width: 36px;
  height: 36px;
}

.logo-text {
  color: var(--c-dark);
}

.navbar:not(.scrolled) .logo-text {
  color: var(--c-white);
}

.logo-accent {
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-menu {
  display: flex;
  gap: 32px;
}

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--c-white);
  opacity: 0.85;
  transition: var(--t-fast);
  position: relative;
  padding: 4px 0;
}

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

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--grad-primary);
  border-radius: 2px;
  transition: var(--t-normal);
}

.nav-link:hover,
.nav-link.active {
  opacity: 1;
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--c-white);
  border-radius: 2px;
  transition: var(--t-normal);
}

.navbar.scrolled .nav-toggle span {
  background: var(--c-dark);
}

.nav-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  background: var(--grad-hero);
  padding: 120px 0 60px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.5;
}

.blob-1 {
  width: 500px;
  height: 500px;
  background: var(--c-primary);
  top: -100px;
  left: -100px;
  animation: blob-float 20s ease-in-out infinite;
}

.blob-2 {
  width: 400px;
  height: 400px;
  background: var(--c-secondary);
  bottom: -50px;
  right: -50px;
  animation: blob-float 25s ease-in-out infinite reverse;
}

.blob-3 {
  width: 350px;
  height: 350px;
  background: var(--c-accent);
  top: 40%;
  left: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.2;
  animation: blob-float 30s ease-in-out infinite;
}

@keyframes blob-float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  25% { transform: translate(50px, -50px) scale(1.1); }
  50% { transform: translate(-30px, 30px) scale(0.95); }
  75% { transform: translate(-50px, -30px) scale(1.05); }
}

.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 70%);
}

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

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  margin-bottom: 32px;
  animation: fade-in-up 0.8s ease forwards;
}

.badge-dot {
  width: 8px;
  height: 8px;
  background: #4ADE80;
  border-radius: 50%;
  box-shadow: 0 0 10px rgba(74, 222, 128, 0.6);
  animation: pulse 2s ease infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.7; transform: scale(1.3); }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -1.5px;
  color: var(--c-white);
  margin-bottom: 24px;
  animation: fade-in-up 0.8s ease 0.1s forwards;
  opacity: 0;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.8;
  margin-bottom: 40px;
  animation: fade-in-up 0.8s ease 0.2s forwards;
  opacity: 0;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  animation: fade-in-up 0.8s ease 0.3s forwards;
  opacity: 0;
}

.hero-scroll {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  margin-top: 60px;
  color: rgba(255, 255, 255, 0.4);
  font-size: 12px;
  letter-spacing: 2px;
  animation: fade-in-up 0.8s ease 0.4s forwards;
  opacity: 0;
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, rgba(255, 255, 255, 0.4), transparent);
  position: relative;
  overflow: hidden;
}

.scroll-line::after {
  content: '';
  position: absolute;
  top: -40px;
  left: 0;
  width: 100%;
  height: 40px;
  background: linear-gradient(to bottom, transparent, var(--c-white));
  animation: scroll-down 2s ease infinite;
}

@keyframes scroll-down {
  0% { top: -40px; }
  100% { top: 40px; }
}

@keyframes fade-in-up {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Stats Section ===== */
.stats {
  padding: 60px 0;
  background: var(--c-white);
  border-bottom: 1px solid var(--c-border);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.stat-item {
  text-align: center;
  padding: 20px;
}

.stat-number {
  font-size: 2.8rem;
  font-weight: 800;
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -1px;
  line-height: 1.2;
}

.stat-label {
  font-size: 14px;
  color: var(--c-gray);
  font-weight: 500;
  margin-top: 4px;
}

/* ===== About Section ===== */
.about {
  background: var(--c-light);
}

.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.about-visual {
  position: relative;
  height: 420px;
}

.about-card-stack {
  position: relative;
  width: 100%;
  height: 100%;
}

.about-card {
  position: absolute;
  background: var(--c-white);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-md);
  transition: var(--t-normal);
  border: 1px solid var(--c-border);
}

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

.about-card-1 {
  top: 0;
  left: 0;
  width: 240px;
  z-index: 3;
}

.about-card-2 {
  top: 80px;
  right: 0;
  width: 240px;
  z-index: 2;
}

.about-card-3 {
  bottom: 0;
  left: 40px;
  width: 240px;
  z-index: 1;
}

.about-card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: var(--c-white);
}

.about-card-1 .about-card-icon { background: linear-gradient(135deg, #6C5CE7, #8B7FF0); }
.about-card-2 .about-card-icon { background: linear-gradient(135deg, #E84393, #F472B6); }
.about-card-3 .about-card-icon { background: linear-gradient(135deg, #FDCB6E, #F0A500); }

.about-card-icon svg {
  width: 24px;
  height: 24px;
}

.about-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--c-dark);
}

.about-card p {
  font-size: 14px;
  color: var(--c-gray);
}

.about-features {
  margin-top: 28px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.about-feature {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 15px;
  color: var(--c-dark);
  line-height: 1.6;
}

.check-icon {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  background: var(--grad-primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--c-white);
  margin-top: 2px;
}

.check-icon svg {
  width: 14px;
  height: 14px;
}

/* ===== Applications Section ===== */
.applications {
  background: var(--c-white);
}

.app-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  margin-top: 48px;
}

.app-card {
  position: relative;
  background: var(--c-white);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  border: 1px solid var(--c-border);
  transition: var(--t-normal);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.app-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--card-grad, var(--grad-primary));
  opacity: 0;
  transition: var(--t-normal);
}

.app-card::after {
  content: '';
  position: absolute;
  bottom: -100px;
  right: -100px;
  width: 200px;
  height: 200px;
  background: var(--card-grad, var(--grad-primary));
  border-radius: 50%;
  filter: blur(60px);
  opacity: 0;
  transition: var(--t-normal);
  z-index: 0;
}

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

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

.app-card:hover::after {
  opacity: 0.08;
}

.app-card > * {
  position: relative;
  z-index: 1;
}

.app-card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  background: var(--card-grad, var(--grad-primary));
  color: var(--c-white);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
  transition: var(--t-normal);
}

.app-card:hover .app-card-icon {
  transform: scale(1.1) rotate(-5deg);
}

.app-card-icon svg {
  width: 28px;
  height: 28px;
}

.app-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.app-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--c-dark);
  letter-spacing: -0.3px;
}

.app-card-status {
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 100px;
  letter-spacing: 0.3px;
}

.app-card-status.online {
  background: rgba(74, 222, 128, 0.12);
  color: #16A34A;
}

.app-card-status.beta {
  background: rgba(253, 203, 110, 0.18);
  color: #B45309;
}

.app-card-status.soon {
  background: rgba(156, 163, 175, 0.15);
  color: var(--c-gray);
}

.app-card-desc {
  font-size: 14px;
  color: var(--c-gray);
  line-height: 1.7;
  margin-bottom: 16px;
}

.app-card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.app-card-tag {
  font-size: 12px;
  padding: 4px 12px;
  background: var(--c-light-2);
  border-radius: 100px;
  color: var(--c-gray);
  font-weight: 500;
}

.app-card-link {
  margin-top: auto;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
  color: var(--c-primary);
  transition: var(--t-fast);
}

.app-card-link svg {
  width: 16px;
  height: 16px;
  transition: var(--t-fast);
}

.app-card-link:hover {
  gap: 10px;
}

.app-card-link.disabled {
  color: var(--c-gray-light);
  cursor: not-allowed;
}

.app-card-link.disabled:hover {
  gap: 6px;
}

/* ===== Features Section ===== */
.features {
  background: var(--c-light);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 48px;
}

.feature-card {
  background: var(--c-white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  border: 1px solid var(--c-border);
  transition: var(--t-normal);
}

.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: transparent;
}

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  color: var(--c-white);
}

.feature-icon svg {
  width: 28px;
  height: 28px;
}

.feature-icon-1 { background: linear-gradient(135deg, #6C5CE7, #8B7FF0); }
.feature-icon-2 { background: linear-gradient(135deg, #E84393, #F472B6); }
.feature-icon-3 { background: linear-gradient(135deg, #00B894, #00CEC9); }
.feature-icon-4 { background: linear-gradient(135deg, #FDCB6E, #F0A500); }

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--c-dark);
}

.feature-card p {
  font-size: 14px;
  color: var(--c-gray);
  line-height: 1.7;
}

/* ===== CTA Section ===== */
.cta-section {
  padding: 80px 0;
  background: var(--c-white);
}

.cta-box {
  position: relative;
  background: var(--c-darker);
  border-radius: var(--radius-xl);
  padding: 80px 40px;
  text-align: center;
  overflow: hidden;
}

.cta-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.cta-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.3;
}

.cta-blob-1 {
  width: 300px;
  height: 300px;
  background: var(--c-primary);
  top: -50px;
  left: -50px;
}

.cta-blob-2 {
  width: 300px;
  height: 300px;
  background: var(--c-secondary);
  bottom: -50px;
  right: -50px;
}

.cta-content {
  position: relative;
  z-index: 1;
}

.cta-title {
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 800;
  color: var(--c-white);
  line-height: 1.3;
  letter-spacing: -1px;
  margin-bottom: 16px;
}

.cta-desc {
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 32px;
}

.cta-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
}

/* ===== Footer ===== */
.footer {
  background: var(--c-darker);
  color: rgba(255, 255, 255, 0.7);
  padding: 80px 0 30px;
}

.footer .logo-text {
  color: var(--c-white);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand .nav-logo {
  margin-bottom: 16px;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 20px;
  max-width: 320px;
}

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

.social-link {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.6);
  transition: var(--t-normal);
}

.social-link:hover {
  background: var(--grad-primary);
  color: var(--c-white);
  transform: translateY(-3px);
}

.footer-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--c-white);
  margin-bottom: 20px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-links a,
.footer-links span {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.5);
  transition: var(--t-fast);
}

.footer-links a:hover {
  color: var(--c-white);
}

.footer-contact-item {
  display: flex;
  align-items: center;
  gap: 8px;
  color: rgba(255, 255, 255, 0.5);
}

.footer-contact-item svg {
  flex-shrink: 0;
  color: var(--c-primary-light);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.4);
}

.footer-icp a {
  color: rgba(255, 255, 255, 0.4);
  transition: var(--t-fast);
}

.footer-icp a:hover {
  color: rgba(255, 255, 255, 0.7);
}

/* ===== Back to Top ===== */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--grad-primary);
  color: var(--c-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: var(--t-normal);
}

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

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}

/* ===== Scroll Reveal Animation ===== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1), transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .about-grid {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about-visual {
    height: 360px;
    max-width: 500px;
    margin: 0 auto;
  }

  .app-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 768px) {
  .nav-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 75%;
    max-width: 320px;
    height: 100vh;
    background: var(--c-white);
    flex-direction: column;
    padding: 100px 32px 40px;
    gap: 8px;
    box-shadow: -10px 0 40px rgba(0, 0, 0, 0.1);
    transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 999;
  }

  .nav-menu.active {
    right: 0;
  }

  .nav-menu .nav-link {
    color: var(--c-dark);
    font-size: 18px;
    padding: 12px 0;
    display: block;
    border-bottom: 1px solid var(--c-border);
    opacity: 1;
  }

  .nav-actions .btn-primary {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .navbar:not(.scrolled) .nav-toggle span {
    background: var(--c-white);
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 1.8rem;
  }

  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .stat-number {
    font-size: 2.2rem;
  }

  .app-grid {
    grid-template-columns: 1fr;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .hero-actions .btn {
    width: 100%;
    max-width: 280px;
  }

  .cta-actions {
    flex-direction: column;
    align-items: center;
  }

  .cta-actions .btn {
    width: 100%;
    max-width: 280px;
  }

  .cta-box {
    padding: 50px 24px;
  }

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

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .about-card {
    width: 200px !important;
    padding: 20px;
  }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 0.95rem;
  }

  .stats-grid {
    grid-template-columns: 1fr;
  }
}