/* ========================================
   霁间 JIJIAN 官网样式
   东方极简 · 敏感肌专研
   ======================================== */

/* ---------- CSS Variables ---------- */
:root {
  /* 色调：霁色 - 雨过天青，明净克制 */
  --color-primary: #39494C;      /* 霁墨色 - 主色调，克制沉稳 */
  --color-accent: #8FA79A;      /* 霁青色 - 点缀，留白透气 */
  --color-accent-light: #C5D0C8;/* 浅霁青 - 辅助 */
  --color-accent-warm: #B5A99A; /* 霁金 - 一点点温度 */

  /* 背景：暖象牙白，非纯白 */
  --color-bg: #F7F5F2;          /* 主背景 */
  --color-bg-warm: #EFECEA;     /* 微暖背景 */
  --color-white: #FFFFFF;

  /* 文字 */
  --color-text: #1A1A1A;        /* 近墨黑，暖调 */
  --color-text-secondary: #4A4A4A; /* 次要文字 */
  --color-muted: #888888;       /* 辅助文字 */

  /* 边框 */
  --color-border: #E2DED8;
  --color-border-light: #EDEBE8;

  /* 字体 */
  --font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "LantingHei SC", "Microsoft YaHei", sans-serif;

  /* 间距 */
  --spacing-xs: 6px;
  --spacing-sm: 12px;
  --spacing-md: 20px;
  --spacing-lg: 40px;
  --spacing-xl: 72px;
  --spacing-xxl: 120px;

  /* 尺寸 */
  --max-width: 1100px;
  --nav-height: 68px;
}

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

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

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

ul { list-style: none; }
img { max-width: 100%; display: block; }

/* ---------- Typography ---------- */
h1 {
  font-size: 2rem;
  font-weight: 300;
  letter-spacing: 0.25em;
  line-height: 1.4;
  color: var(--color-text);
}

h2 {
  font-size: 1.5rem;
  font-weight: 300;
  letter-spacing: 0.12em;
  color: var(--color-text);
}

h3 {
  font-size: 1.125rem;
  font-weight: 400;
  letter-spacing: 0.06em;
}

p {
  font-size: 0.9375rem;
  line-height: 2;
  color: var(--color-text-secondary);
}

/* ---------- Page Header ---------- */
.page-header {
  padding: calc(var(--nav-height) + var(--spacing-xl)) 0 var(--spacing-xl);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border-light);
  text-align: center;
}

.page-header h1 {
  font-size: 1.5rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  margin-bottom: var(--spacing-xs);
}

.page-header p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

.page-header-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-xs);
}

.page-title {
  font-size: 1.5rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  color: var(--color-text);
}

.page-subtitle {
  font-size: 0.8125rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

/* ---------- Container ---------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

/* ---------- Navigation ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-height);
  background: rgba(247, 245, 242, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 1000;
  border-bottom: 1px solid var(--color-border-light);
}

.nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.25em;
  color: var(--color-text);
}

.nav-logo span {
  font-weight: 600;
  letter-spacing: 0.3em;
  margin-right: 2px;
}

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-links a {
  font-size: 0.8125rem;
  color: var(--color-muted);
  letter-spacing: 0.08em;
  transition: color 0.2s;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-text);
  border-bottom-color: var(--color-accent);
}

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

.nav-toggle span {
  width: 18px;
  height: 1px;
  background: var(--color-text);
  transition: all 0.3s;
}

/* ---------- Mobile Nav ---------- */
@media (max-width: 768px) {
  .nav-toggle { display: flex; }

  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0; right: 0;
    background: rgba(247, 245, 242, 0.97);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    flex-direction: column;
    padding: var(--spacing-md) var(--spacing-lg);
    gap: var(--spacing-sm);
    border-bottom: 1px solid var(--color-border);
    transform: translateY(calc(-100% - var(--nav-height)));
    opacity: 0;
    visibility: hidden;
    transition: transform 0.28s cubic-bezier(0.4, 0, 0.2, 1),
                opacity 0.28s cubic-bezier(0.4, 0, 0.2, 1),
                visibility 0.28s;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-links a {
    padding: var(--spacing-sm) 0;
    font-size: 0.9375rem;
  }
}

/* ---------- Hero ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding-top: var(--nav-height);
  position: relative;
  background: var(--color-bg);
}

/* 留白分割线，借鉴至本极简 */
.hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 1px;
  height: 60px;
  background: var(--color-border);
}

.hero-logo {
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.35em;
  color: var(--color-text);
  margin-bottom: var(--spacing-sm);
}

.hero-slogan {
  font-size: 0.8125rem;
  color: var(--color-muted);
  letter-spacing: 0.2em;
  font-weight: 300;
}

.hero-en {
  font-size: 0.6875rem;
  color: var(--color-accent);
  letter-spacing: 0.4em;
  margin-top: var(--spacing-xs);
  font-weight: 300;
}

/* ---------- Section ---------- */
.section {
  padding: var(--spacing-xxl) 0;
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.section-title h2 {
  font-weight: 300;
  letter-spacing: 0.15em;
  margin-bottom: var(--spacing-sm);
}

.section-title p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
}

/* ---------- Values ---------- */
.values {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--color-border-light);
  border: 1px solid var(--color-border-light);
}

.value-item {
  background: var(--color-bg);
  padding: var(--spacing-xl) var(--spacing-lg);
  text-align: center;
}

.value-item:hover {
  background: var(--color-white);
  transition: background 0.3s;
}

.value-icon {
  width: 44px;
  height: 44px;
  color: var(--color-accent);
  margin: 0 auto var(--spacing-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.value-item h3 {
  font-size: 0.9375rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  color: var(--color-text);
  margin-bottom: var(--spacing-sm);
}

.value-item p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  line-height: 1.9;
}

@media (max-width: 768px) {
  .values { grid-template-columns: 1fr; }
}

/* ---------- Products Preview ---------- */
.products-preview {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-sm);
}

.product-card {
  background: var(--color-white);
  padding: var(--spacing-lg);
  border: 1px solid var(--color-border-light);
  transition: border-color 0.3s, box-shadow 0.3s;
}

.product-card:hover {
  border-color: var(--color-accent-light);
  box-shadow: 0 4px 24px rgba(57,73,76,0.08);
}

.product-name {
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

.product-effect {
  font-size: 0.8125rem;
  color: var(--color-accent);
  margin-bottom: var(--spacing-sm);
  letter-spacing: 0.05em;
}

.product-brief {
  font-size: 0.8125rem;
  color: var(--color-muted);
  line-height: 1.8;
}

.product-link {
  display: inline-block;
  margin-top: var(--spacing-md);
  font-size: 0.75rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
  transition: color 0.2s;
}

.product-link:hover {
  color: var(--color-text);
}

@media (max-width: 768px) {
  .products-preview { grid-template-columns: 1fr; }
}

/* ---------- Origin ---------- */
.origin {
  background: var(--color-white);
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
}

.origin-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
  align-items: center;
}

.origin-text h3 {
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.12em;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.origin-list {
  border-top: 1px solid var(--color-border-light);
}

.origin-list li {
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--color-border-light);
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-sm);
  line-height: 1.7;
}

.origin-list li::before {
  content: '—';
  color: var(--color-accent);
  flex-shrink: 0;
  font-size: 0.75rem;
  margin-top: 2px;
}

.origin-visual {
  aspect-ratio: 4/3;
  background: var(--color-bg-warm);
  border: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

/* 产区示意 — CSS-only 细线网格 + 三点 */
.origin-visual::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--color-border-light) 1px, transparent 1px),
    linear-gradient(90deg, var(--color-border-light) 1px, transparent 1px);
  background-size: 40px 40px;
  opacity: 0.6;
}

.origin-dots {
  display: flex;
  flex-direction: column;
  gap: 18px;
  position: relative;
  z-index: 1;
}

.origin-dot {
  display: flex;
  align-items: center;
  gap: 12px;
}

.origin-dot-mark {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent);
  flex-shrink: 0;
}

.origin-dot-line {
  width: 32px;
  height: 1px;
  background: var(--color-accent-light);
}

.origin-dot-label {
  font-size: 0.6875rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
}

@media (max-width: 768px) {
  .origin-content { grid-template-columns: 1fr; }
  .origin-visual { order: -1; }
}

/* ---------- Trust ---------- */
.trust-list {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  flex-wrap: wrap;
}

.trust-item {
  text-align: center;
  min-width: 180px;
  padding: var(--spacing-md);
}

.trust-item .number {
  font-size: 1rem;
  color: var(--color-accent);
  margin-bottom: var(--spacing-xs);
  letter-spacing: 0.05em;
  font-weight: 300;
}

.trust-item .label {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---------- CTA ---------- */
.cta-section {
  text-align: center;
  padding: var(--spacing-xxl) 0;
  background: var(--color-white);
  border-top: 1px solid var(--color-border-light);
}

.cta-section h2 {
  font-size: 1.25rem;
  font-weight: 300;
  letter-spacing: 0.15em;
  margin-bottom: var(--spacing-sm);
}

.cta-section p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  margin-bottom: var(--spacing-lg);
}

.cta-btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  background: var(--color-text);
  color: var(--color-white);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  transition: opacity 0.2s, background 0.2s;
}

.cta-btn:hover {
  background: var(--color-primary);
  opacity: 1;
}

.cta-btn-ghost {
  display: inline-block;
  padding: 10px var(--spacing-lg);
  background: transparent;
  color: var(--color-text);
  font-size: 0.75rem;
  letter-spacing: 0.2em;
  border: 1px solid var(--color-border);
  transition: border-color 0.2s, color 0.2s;
}

.cta-btn-ghost:hover {
  border-color: var(--color-text);
  color: var(--color-text);
}

/* ---------- Product Detail ---------- */
.product-detail {
  padding: var(--spacing-xl) 0;
  border-bottom: 1px solid var(--color-border-light);
}

.product-detail:last-child { border-bottom: none; }

.product-detail-inner {
  display: grid;
  grid-template-columns: 1fr 1.5fr;
  gap: var(--spacing-xl);
  align-items: start;
}

.product-visual {
  aspect-ratio: 1;
  background: var(--color-white);
  border: 1px solid var(--color-border-light);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-accent);
  font-size: 0.6875rem;
  letter-spacing: 0.2em;
}

.product-info h3 {
  font-size: 1.25rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  margin-bottom: var(--spacing-xs);
}

.product-info .effect {
  font-size: 0.8125rem;
  color: var(--color-accent);
  margin-bottom: var(--spacing-md);
  letter-spacing: 0.08em;
}

.product-info .desc {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 2;
}

.product-info .ingredients,
.product-info .origin-info {
  margin-top: var(--spacing-md);
  padding-top: var(--spacing-md);
  border-top: 1px solid var(--color-border-light);
}

.product-info h4 {
  font-size: 0.75rem;
  font-weight: 400;
  letter-spacing: 0.15em;
  color: var(--color-muted);
  margin-bottom: var(--spacing-xs);
  text-transform: uppercase;
}

.product-info .ingredients p,
.product-info .origin-info p {
  font-size: 0.8125rem;
  color: var(--color-text-secondary);
  line-height: 1.9;
}

@media (max-width: 768px) {
  .product-detail-inner { grid-template-columns: 1fr; gap: var(--spacing-md); }
}

/* ---------- About Page ---------- */
.about-intro {
  max-width: 680px;
  margin: 0 auto;
  text-align: center;
  padding: var(--spacing-xxl) 0;
}

.about-intro p {
  font-size: 1rem;
  line-height: 2.2;
  color: var(--color-text-secondary);
}

.principles {
  background: var(--color-white);
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
  padding: var(--spacing-xxl) 0;
}

.principle-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--color-border-light);
  border: 1px solid var(--color-border-light);
  max-width: 800px;
  margin: 0 auto;
}

.principle-item {
  background: var(--color-white);
  padding: var(--spacing-lg);
}

.principle-item h3 {
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  color: var(--color-text);
  margin-bottom: var(--spacing-sm);
}

.principle-item p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  line-height: 1.9;
}

.story {
  padding: var(--spacing-xxl) 0;
}

.story-content {
  max-width: 680px;
  margin: 0 auto;
}

.story-content p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 2.1;
  margin-bottom: var(--spacing-md);
}

@media (max-width: 768px) {
  .principle-list { grid-template-columns: 1fr; }
}

/* ---------- Guide Page ---------- */
.guide-list {
  display: flex;
  flex-direction: column;
  gap: 1px;
  background: var(--color-border-light);
  border: 1px solid var(--color-border-light);
  max-width: 800px;
  margin: 0 auto;
}

.guide-item {
  background: var(--color-white);
  padding: var(--spacing-lg);
  transition: background 0.2s;
}

.guide-item:hover {
  background: var(--color-bg);
}

.guide-item h3 {
  font-size: 0.9375rem;
  font-weight: 400;
  letter-spacing: 0.08em;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

.guide-item .date {
  font-size: 0.75rem;
  color: var(--color-muted);
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-sm);
}

.guide-item p {
  font-size: 0.8125rem;
  color: var(--color-muted);
  line-height: 1.8;
}

.guide-item .read-more {
  display: inline-block;
  margin-top: var(--spacing-sm);
  font-size: 0.75rem;
  color: var(--color-accent);
  letter-spacing: 0.05em;
}

/* ---------- Contact Page ---------- */
.contact-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
}

.contact-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: var(--spacing-xl) var(--spacing-lg);
  background: var(--color-white);
  border: 1px solid var(--color-border-light);
  transition: box-shadow 0.3s, border-color 0.3s;
}

.contact-card:hover {
  box-shadow: 0 4px 20px rgba(0,0,0,0.06);
  border-color: var(--color-accent-light);
}

.contact-card-icon {
  width: 44px;
  height: 44px;
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  color: var(--color-accent);
}

.contact-card-icon svg {
  width: 20px;
  height: 20px;
}

.contact-card-label {
  font-size: 0.6875rem;
  color: var(--color-muted);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: var(--spacing-xs);
}

.contact-card-value {
  font-size: 1rem;
  color: var(--color-text);
  line-height: 1.6;
}

.contact-card-value a {
  color: var(--color-text);
  text-decoration: none;
  transition: color 0.2s;
}

.contact-card-value a:hover {
  color: var(--color-accent);
}

.contact-tip {
  text-align: center;
  padding: var(--spacing-lg);
  background: var(--color-bg);
  border-top: 1px solid var(--color-border-light);
  border-bottom: 1px solid var(--color-border-light);
  color: var(--color-muted);
  font-size: 0.8125rem;
  line-height: 2;
}

.contact-tip p {
  margin: 0;
}

@media (max-width: 768px) {
  .contact-cards { grid-template-columns: 1fr; }
}

/* ---------- Footer ---------- */
.footer {
  background: var(--color-text);
  color: var(--color-white);
  padding: var(--spacing-lg) 0;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--spacing-lg);
  padding-bottom: var(--spacing-lg);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-brand {
  font-size: 0.875rem;
  font-weight: 400;
  letter-spacing: 0.25em;
  color: var(--color-white);
  margin-bottom: var(--spacing-sm);
}

.footer-desc {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.35);
  line-height: 1.8;
}

.footer-col h4 {
  font-size: 0.6875rem;
  font-weight: 400;
  letter-spacing: 0.15em;
  color: rgba(255,255,255,0.3);
  margin-bottom: var(--spacing-sm);
  text-transform: uppercase;
}

.footer-col a {
  display: block;
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.5);
  padding: 3px 0;
  transition: color 0.2s;
}

.footer-col a:hover {
  color: rgba(255,255,255,0.9);
}

@media (max-width: 768px) {
  .footer-content { grid-template-columns: 1fr 1fr; gap: var(--spacing-md); }
  .footer-bottom { padding: var(--spacing-md) 0; }
  .footer-beian-line { flex-direction: column; gap: 6px; }
  .beian-divider { display: none; }
}

/* ---------- Page Header ---------- */
.page-header {
  padding: calc(var(--nav-height) + var(--spacing-xl)) 0 var(--spacing-lg);
  text-align: center;
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border-light);
}

.page-header h1 {
  font-size: 1.5rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  margin-bottom: var(--spacing-xs);
}

.page-header p {
  font-size: 0.8125rem;
  color: var(--color-muted);
}

/* ---------- Utility ---------- */
.text-accent { color: var(--color-accent); }
.text-muted { color: var(--color-muted); }
.text-center { text-align: center; }
.mt-lg { margin-top: var(--spacing-lg); }

/* ---------- Regulatory Notice ---------- */
.regulatory-notice {
  background: var(--color-bg);
  border: 1px solid var(--color-border-light);
  border-radius: 8px;
  padding: var(--spacing-lg);
  font-size: 0.8125rem;
  color: var(--color-muted);
  line-height: 1.8;
}

.regulatory-notice p {
  margin-bottom: 8px;
  color: var(--color-muted);
}

.regulatory-notice p:last-child { margin-bottom: 0; }

.regulatory-notice a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: var(--color-bg); }
::-webkit-scrollbar-thumb { background: var(--color-border); }
::-webkit-scrollbar-thumb:hover { background: var(--color-accent-light); }


/* ---------- Footer Bottom ---------- */
.footer-bottom {
  padding: var(--spacing-lg) 0;
  text-align: center;
}

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

.footer-copyright-line {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.35);
  letter-spacing: 0.05em;
}

.footer-beian-line {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.35);
}

.footer-beian-line a {
  color: rgba(255,255,255,0.35);
  transition: color 0.2s;
}

.footer-beian-line a:hover {
  color: rgba(255,255,255,0.65);
}

.beian-divider {
  color: rgba(255,255,255,0.15);
  user-select: none;
}

.beian-icon {
  height: 9px;
  width: auto;
  vertical-align: -1px;
  margin-right: 4px;
}

/* ---------- Page Header ---------- */

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: var(--spacing-lg);
  right: var(--spacing-lg);
  width: 40px;
  height: 40px;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s, box-shadow 0.2s;
  z-index: 900;
}

.back-to-top svg {
  width: 16px;
  height: 16px;
  color: var(--color-text);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  box-shadow: 0 2px 12px rgba(57,73,76,0.12);
}