/* ============================================================
   CALEB'S SPACE — Main Stylesheet
   Color System (from "生命科学 × 人文探索" AI consultation)
   ============================================================ */

/* ---- CSS CUSTOM PROPERTIES ---- */
:root {
  /* Brand */
  --brand:        #EF6C00;   /* Warm Orange — main CTA, logo */
  --brand-light:  #FFF3E0;
  --brand-dark:   #BF360C;

  /* Section A — Daily Life */
  --life:         #8D6E63;   /* Taupe Brown — 土壤/陶土 */
  --life-light:   #EFEBE9;
  --life-dark:    #5D4037;

  /* Section B — Travel */
  --travel:       #5C6BC0;   /* Indigo — 天空/深海 */
  --travel-light: #E8EAF6;
  --travel-dark:  #283593;

  /* Section C — Professional (Core) */
  --pro:          #43A047;   /* Emerald Green — 活细胞/叶绿素 */
  --pro-light:    #E8F5E9;
  --pro-dark:     #1B5E20;

  /* Section D — Thinking */
  --think:        #FF8A65;   /* Soft Amber — 晨光/智慧之光 */
  --think-light:  #FBE9E7;
  --think-dark:   #BF360C;

  /* Neutrals */
  --bg:           #FAFAFA;
  --surface:      #FFFFFF;
  --text-primary: #263238;
  --text-secondary:#78909C;
  --divider:      #ECEFF1;
  --border:       #CFD8DC;

  /* Typography */
  --font-serif:   "Noto Serif SC", Georgia, serif;
  --font-sans:    "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;

  /* Spacing */
  --radius-sm:    6px;
  --radius:       12px;
  --radius-lg:    20px;
  --shadow-sm:    0 2px 8px rgba(38,50,56,.08);
  --shadow:       0 4px 20px rgba(38,50,56,.12);
  --shadow-lg:    0 8px 40px rgba(38,50,56,.16);
  --transition:   0.25s cubic-bezier(.4,0,.2,1);
}

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

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

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

.desktop-br { display: block; }
@media (max-width: 640px) { .desktop-br { display: none; } }

/* ============================================================
   HEADER / NAV
   ============================================================ */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(250,250,250,.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--divider);
  transition: box-shadow var(--transition);
}
.site-header.scrolled { box-shadow: var(--shadow-sm); }

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-primary);
}
.logo-icon { font-size: 1.4rem; }
.logo-text { letter-spacing: .02em; }

.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.nav-link {
  padding: 6px 14px;
  border-radius: 99px;
  font-size: .9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: background var(--transition), color var(--transition);
  position: relative;
}
.nav-link:hover { color: var(--text-primary); background: var(--divider); }
.nav-life:hover    { background: var(--life-light);   color: var(--life-dark); }
.nav-travel:hover  { background: var(--travel-light); color: var(--travel-dark); }
.nav-pro:hover     { background: var(--pro-light);    color: var(--pro-dark); }
.nav-think:hover   { background: var(--think-light);  color: var(--think-dark); }

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.hamburger span {
  display: block;
  width: 22px; height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

@media (max-width: 768px) {
  .hamburger { display: flex; }
  .main-nav {
    position: fixed;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    background: var(--surface);
    padding: 12px 16px 20px;
    border-bottom: 1px solid var(--divider);
    box-shadow: var(--shadow);
    transform: translateY(-120%);
    opacity: 0;
    transition: transform var(--transition), opacity var(--transition);
    pointer-events: none;
  }
  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }
  .nav-link { padding: 12px 16px; border-radius: var(--radius-sm); }
}

/* ============================================================
   BUTTONS
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 11px 26px;
  border-radius: 99px;
  font-size: .95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  letter-spacing: .02em;
}
.btn-primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 2px 12px rgba(239,108,0,.35);
}
.btn-primary:hover {
  background: var(--brand-dark);
  box-shadow: 0 4px 20px rgba(239,108,0,.45);
  transform: translateY(-1px);
}
.btn-ghost {
  background: transparent;
  color: var(--text-primary);
  border: 1.5px solid var(--border);
}
.btn-ghost:hover {
  background: var(--surface);
  border-color: var(--text-primary);
  transform: translateY(-1px);
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding: 80px 0 60px;
}

/* subtle dot grid */
.hero-bg-grid {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, var(--divider) 1.5px, transparent 1.5px);
  background-size: 28px 28px;
  opacity: .7;
  pointer-events: none;
}

/* gradient overlay bottom */
.hero::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 160px;
  background: linear-gradient(to bottom, transparent, var(--bg));
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
  animation: fadeUp .8s ease both;
}

.hero-eyebrow {
  font-size: .85rem;
  letter-spacing: .15em;
  text-transform: uppercase;
  color: var(--brand);
  font-weight: 600;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 24px; height: 2px;
  background: var(--brand);
  border-radius: 2px;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 5vw, 3.4rem);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: 24px;
}

.hero-highlight {
  color: var(--brand);
  position: relative;
}
.hero-highlight::after {
  content: '';
  position: absolute;
  left: 0; bottom: -4px;
  width: 100%; height: 3px;
  background: linear-gradient(to right, var(--brand), var(--pro));
  border-radius: 3px;
  transform: scaleX(0);
  transform-origin: left;
  animation: underlineIn 1s .6s ease forwards;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.9;
  margin-bottom: 36px;
}

.hero-cta {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}

/* DNA decoration */
.hero-dna {
  position: absolute;
  right: 80px;
  top: 50%;
  transform: translateY(-50%);
  width: 120px;
  height: 400px;
  z-index: 1;
  pointer-events: none;
  animation: floatDNA 6s ease-in-out infinite;
}
@media (max-width: 900px) { .hero-dna { display: none; } }

/* ============================================================
   SECTIONS OVERVIEW
   ============================================================ */
.sections-overview {
  padding: 100px 0 80px;
}

.section-heading {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
}
.section-heading.center { text-align: center; }
.section-sub {
  font-size: .95rem;
  color: var(--text-secondary);
  margin-bottom: 56px;
}
.section-sub.center { text-align: center; }

.cards-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

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

/* Card base */
.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 32px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1.5px solid var(--divider);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  overflow: hidden;
  cursor: pointer;
}
.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  border-radius: 4px 4px 0 0;
}
.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

/* Card color variants */
.card-life::before   { background: linear-gradient(to right, var(--life), #A1887F); }
.card-life:hover     { border-color: var(--life); }
.card-travel::before { background: linear-gradient(to right, var(--travel), #7986CB); }
.card-travel:hover   { border-color: var(--travel); }
.card-pro::before    { background: linear-gradient(to right, var(--pro), #66BB6A); }
.card-pro:hover      { border-color: var(--pro); }
.card-think::before  { background: linear-gradient(to right, var(--think), #FFAB91); }
.card-think:hover    { border-color: var(--think); }

/* Professional card special treatment */
.card-pro {
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pro-light) 100%);
}

.card-icon-wrap {
  width: 48px; height: 48px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
}
.card-icon-wrap svg { width: 26px; height: 26px; }

.card-life   .card-icon-wrap { background: var(--life-light);   color: var(--life); }
.card-travel .card-icon-wrap { background: var(--travel-light); color: var(--travel); }
.card-pro    .card-icon-wrap { background: var(--pro-light);    color: var(--pro); }
.card-think  .card-icon-wrap { background: var(--think-light);  color: var(--think); }

.card-label {
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.card-life   .card-label { color: var(--life); }
.card-travel .card-label { color: var(--travel); }
.card-pro    .card-label { color: var(--pro); }
.card-think  .card-label { color: var(--think); }

.card-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
}

.card-desc {
  font-size: .9rem;
  color: var(--text-secondary);
  line-height: 1.75;
  flex: 1;
}

.card-meta {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag {
  font-size: .75rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 99px;
}
.tag-life   { background: var(--life-light);   color: var(--life-dark); }
.tag-travel { background: var(--travel-light); color: var(--travel-dark); }
.tag-pro    { background: var(--pro-light);    color: var(--pro-dark); }
.tag-think  { background: var(--think-light);  color: var(--think-dark); }

.card-arrow {
  font-size: 1.1rem;
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity var(--transition), transform var(--transition);
  align-self: flex-end;
}
.card-life   .card-arrow { color: var(--life); }
.card-travel .card-arrow { color: var(--travel); }
.card-pro    .card-arrow { color: var(--pro); }
.card-think  .card-arrow { color: var(--think); }

.card:hover .card-arrow {
  opacity: 1;
  transform: translateX(0);
}

/* ============================================================
   FEATURED ARTICLES
   ============================================================ */
.featured {
  padding: 80px 0;
  background: var(--surface);
  border-top: 1px solid var(--divider);
}

.posts-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-top: 40px;
}

.post-row {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 24px 0;
  border-bottom: 1px solid var(--divider);
  transition: background var(--transition);
  position: relative;
  padding-left: 16px;
}
.post-row:last-child { border-bottom: none; }
.post-row:hover { background: var(--bg); margin: 0 -24px; padding-left: 40px; padding-right: 24px; border-radius: var(--radius); }

.post-cat-dot {
  position: absolute;
  left: 0;
  top: 32px;
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}
.post-life   .post-cat-dot { background: var(--life); }
.post-travel .post-cat-dot { background: var(--travel); }
.post-pro    .post-cat-dot { background: var(--pro); }
.post-think  .post-cat-dot { background: var(--think); }

.post-info { flex: 1; display: flex; flex-direction: column; gap: 6px; }

.post-cat-label {
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .1em;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: 4px;
  width: fit-content;
}
.cat-life   { background: var(--life-light);   color: var(--life-dark); }
.cat-travel { background: var(--travel-light); color: var(--travel-dark); }
.cat-pro    { background: var(--pro-light);    color: var(--pro-dark); }
.cat-think  { background: var(--think-light);  color: var(--think-dark); }

.post-title {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.5;
  transition: color var(--transition);
}
.post-title:hover { color: var(--brand); }

.post-excerpt {
  font-size: .88rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.post-date {
  font-size: .8rem;
  color: var(--text-secondary);
  white-space: nowrap;
  padding-top: 22px;
  opacity: .7;
}

@media (max-width: 600px) {
  .post-row { flex-direction: column; gap: 8px; }
  .post-date { padding-top: 0; }
}

/* ============================================================
   ABOUT STRIP
   ============================================================ */
.about-strip {
  padding: 100px 0;
  background: linear-gradient(135deg, var(--pro-light) 0%, var(--brand-light) 100%);
  border-top: 1px solid var(--divider);
}

.about-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

@media (max-width: 768px) {
  .about-inner { grid-template-columns: 1fr; gap: 40px; }
}

.about-text h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 20px;
  color: var(--text-primary);
}
.about-text p {
  font-size: .95rem;
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: 14px;
}
.about-text .btn { margin-top: 8px; }

.about-card-wrap {
  display: flex;
  justify-content: center;
}

.about-badge-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 360px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.badge-row {
  display: flex;
  align-items: center;
  gap: 14px;
}
.badge-icon { font-size: 1.6rem; width: 40px; text-align: center; }
.badge-title { font-size: .95rem; font-weight: 600; color: var(--text-primary); }
.badge-sub   { font-size: .8rem; color: var(--text-secondary); margin-top: 2px; }

.badge-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding-top: 4px;
  border-top: 1px solid var(--divider);
}
.badge-tag {
  font-size: .75rem;
  font-weight: 500;
  color: var(--pro);
  background: var(--pro-light);
  padding: 3px 10px;
  border-radius: 99px;
}

/* ============================================================
   PAGE HEADERS (for sub-pages)
   ============================================================ */
.page-hero {
  padding: 140px 0 80px;
  position: relative;
  overflow: hidden;
}
.page-hero::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 60px;
  background: linear-gradient(to bottom, transparent, var(--bg));
}
.page-hero-life   { background: linear-gradient(135deg, var(--life-light), #FFF8F6); }
.page-hero-travel { background: linear-gradient(135deg, var(--travel-light), #F5F6FF); }
.page-hero-pro    { background: linear-gradient(135deg, var(--pro-light), var(--brand-light)); }
.page-hero-think  { background: linear-gradient(135deg, var(--think-light), #FFF8F6); }

.page-hero-eyebrow {
  font-size: .8rem;
  letter-spacing: .15em;
  text-transform: uppercase;
  font-weight: 700;
  margin-bottom: 14px;
}
.life-color   { color: var(--life); }
.travel-color { color: var(--travel); }
.pro-color    { color: var(--pro); }
.think-color  { color: var(--think); }
.brand-color  { color: var(--brand); }

.page-hero-title {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: 16px;
}
.page-hero-desc {
  font-size: 1rem;
  color: var(--text-secondary);
  max-width: 600px;
  line-height: 1.85;
}

/* ============================================================
   PLACEHOLDER CONTENT (sub-pages coming soon)
   ============================================================ */
.coming-soon {
  padding: 80px 0 120px;
}
.coming-soon-inner {
  text-align: center;
  max-width: 480px;
  margin: 0 auto;
}
.coming-soon-icon { font-size: 4rem; margin-bottom: 24px; }
.coming-soon-title {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}
.coming-soon-desc {
  font-size: .95rem;
  color: var(--text-secondary);
  line-height: 1.85;
  margin-bottom: 32px;
}

/* ============================================================
   ARTICLE GRID (for sub-pages)
   ============================================================ */
.articles-section {
  padding: 60px 0 100px;
}
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
  margin-top: 40px;
}
.article-card {
  background: var(--surface);
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--divider);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
}
.article-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.article-card-cover {
  height: 180px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  position: relative;
  overflow: hidden;
}
.article-card-cover-life   { background: var(--life-light); }
.article-card-cover-travel { background: var(--travel-light); }
.article-card-cover-pro    { background: var(--pro-light); }
.article-card-cover-think  { background: var(--think-light); }

.article-card-body {
  padding: 20px 22px 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.article-card-title {
  font-family: var(--font-serif);
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.55;
}
.article-card-excerpt {
  font-size: .85rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 12px;
  border-top: 1px solid var(--divider);
  font-size: .8rem;
  color: var(--text-secondary);
}

/* ============================================================
   BLOCKQUOTE / HIGHLIGHT (for article pages)
   ============================================================ */
.blockquote-think {
  background: var(--think-light);
  border-left: 4px solid var(--think);
  padding: 20px 24px;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 24px 0;
  font-style: italic;
  color: var(--text-primary);
  font-size: 1.05rem;
  line-height: 1.8;
}

/* ============================================================
   FOOTER
   ============================================================ */
.site-footer {
  background: var(--text-primary);
  color: rgba(255,255,255,.7);
  padding: 60px 0 40px;
}
.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  text-align: center;
}
.footer-inner .logo-text { color: #fff; font-size: 1.1rem; }
.footer-inner .logo-icon { font-size: 1.4rem; }
.footer-brand {
  display: flex;
  align-items: center;
  gap: 8px;
}
.footer-desc {
  font-size: .88rem;
  color: rgba(255,255,255,.5);
  max-width: 400px;
  line-height: 1.7;
}
.footer-links {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}
.footer-links a {
  padding: 5px 14px;
  border-radius: 99px;
  font-size: .83rem;
  color: rgba(255,255,255,.6);
  transition: background var(--transition), color var(--transition);
}
.footer-links a:hover {
  background: rgba(255,255,255,.1);
  color: #fff;
}
.footer-copy {
  font-size: .78rem;
  color: rgba(255,255,255,.3);
  padding-top: 8px;
}

/* ============================================================
   ANIMATIONS
   ============================================================ */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(28px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes underlineIn {
  to { transform: scaleX(1); }
}
@keyframes floatDNA {
  0%, 100% { transform: translateY(-50%) rotate(0deg); }
  50%       { transform: translateY(calc(-50% - 18px)) rotate(2deg); }
}

/* Scroll reveal helper */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .6s ease, transform .6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}