@import url('https://fonts.googleapis.com/css2?family=Space+Mono:wght@400;700&display=swap');

/* ============================================================
   CSS 自定义属性
   ============================================================ */
:root {
  --c-black: #000000;
  --c-white: #ffffff;
  --c-grey-100: #f5f5f5;
  --c-grey-200: #e8e8e8;
  --c-grey-400: #999999;
  --c-grey-600: #555555;
  --c-accent: #000000;
  --ff-mono: 'Space Mono', 'Courier New', Courier, monospace;
  --ff-sans: var(--ff-mono);
  --fw-regular: 400;
  --fw-bold: 700;
  --base: 8px;
  --sp-1: 8px;
  --sp-2: 16px;
  --sp-3: 24px;
  --sp-4: 32px;
  --sp-5: 40px;
  --sp-6: 48px;
  --sp-8: 64px;
  --sp-10: 80px;
  --sp-12: 96px;
  --max-w: 1200px;
  --border: 1px solid var(--c-black);
  --radius: 0;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--ff-mono);
  font-weight: var(--fw-regular);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--c-black);
  background: var(--c-white);
  overflow-x: hidden;
}

a {
  color: var(--c-black);
  text-decoration: underline;
  text-underline-offset: 3px;
}

a:hover, a:focus {
  text-decoration: none;
  outline: 2px solid var(--c-black);
  outline-offset: 2px;
}

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

ul, ol {
  list-style: none;
}

/* ============================================================
   Grid Container
   ============================================================ */
.grid-container {
  width: 100%;
  max-width: var(--max-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--sp-4);
  padding-right: var(--sp-4);
}

/* ============================================================
   Site Header — two-row: brand + nav
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--c-black);
  color: var(--c-white);
}

.header-brand {
  border-bottom: 1px solid rgba(255,255,255,0.15);
  padding: var(--sp-2) 0;
}

.brand-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
}

.brand-link {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: var(--c-white);
  gap: var(--sp-2);
}

.brand-link:hover, .brand-link:focus {
  outline-color: var(--c-white);
  text-decoration: none;
}

.brand-logo {
  height: 40px;
  width: auto;
}

.brand-text {
  font-family: var(--ff-mono);
  font-weight: var(--fw-bold);
  font-size: 1.125rem;
  letter-spacing: 0.02em;
  color: var(--c-white);
  white-space: nowrap;
}

/* Header search */
.header-search {
  flex-shrink: 0;
}

.header-search form {
  display: flex;
  gap: 0;
  border: 1px solid rgba(255,255,255,0.4);
}

.header-search input[type="search"] {
  background: transparent;
  border: none;
  color: var(--c-white);
  font-family: var(--ff-mono);
  font-size: 0.875rem;
  padding: var(--sp-1) var(--sp-2);
  width: 220px;
  outline: none;
}

.header-search input[type="search"]::placeholder {
  color: rgba(255,255,255,0.5);
}

.header-search button {
  background: var(--c-white);
  border: none;
  color: var(--c-black);
  font-family: var(--ff-mono);
  font-weight: var(--fw-bold);
  font-size: 0.875rem;
  padding: var(--sp-1) var(--sp-2);
  cursor: pointer;
  min-height: 40px;
  min-width: 40px;
  transition: background 0.15s, color 0.15s;
}

.header-search button:hover {
  background: var(--c-grey-200);
}

/* Nav row — structure: nav > p > a */
.header-nav {
  padding: 0;
}

.header-nav nav {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.header-nav nav::-webkit-scrollbar {
  display: none;
}

.header-nav nav > p {
  display: flex;
  gap: 0;
  white-space: nowrap;
  padding: 0;
  margin: 0;
}

.header-nav nav > p > a {
  display: block;
  color: rgba(255,255,255,0.8);
  text-decoration: none;
  font-family: var(--ff-mono);
  font-size: 0.8125rem;
  font-weight: var(--fw-regular);
  padding: var(--sp-2) var(--sp-3);
  border-right: 1px solid rgba(255,255,255,0.1);
  min-height: 44px;
  display: flex;
  align-items: center;
  letter-spacing: 0.01em;
  transition: background 0.15s, color 0.15s;
}

.header-nav nav > p > a:first-child {
  border-left: none;
}

.header-nav nav > p > a:hover,
.header-nav nav > p > a:focus {
  background: rgba(255,255,255,0.1);
  color: var(--c-white);
  outline: none;
  text-decoration: none;
}

/* ============================================================
   Hero — 100vh + clip-path bottom
   ============================================================ */
.hero {
  position: relative;
  width: 100%;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
  background: var(--c-black);
}

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

.hero-media--blank {
  background: linear-gradient(135deg, #111 0%, #333 50%, #000 100%);
}

.hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.55;
}

.hero-content {
  position: relative;
  z-index: 2;
  padding-bottom: var(--sp-12);
  padding-top: var(--sp-10);
}

.hero-text {
  max-width: 700px;
}

.hero-eyebrow {
  font-family: var(--ff-mono);
  font-size: 0.75rem;
  font-weight: var(--fw-bold);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.6);
  margin-bottom: var(--sp-2);
}

.hero h1 {
  font-family: var(--ff-mono);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: var(--fw-bold);
  color: var(--c-white);
  line-height: 1.15;
  margin-bottom: var(--sp-3);
  letter-spacing: -0.01em;
}

.hero-sub {
  font-size: 1.0625rem;
  color: rgba(255,255,255,0.75);
  margin-bottom: var(--sp-5);
  max-width: 560px;
}

.hero-btn {
  display: inline-block;
  background: var(--c-white);
  color: var(--c-black);
  font-family: var(--ff-mono);
  font-weight: var(--fw-bold);
  font-size: 0.9375rem;
  padding: var(--sp-2) var(--sp-5);
  text-decoration: none;
  border: 2px solid var(--c-white);
  min-height: 48px;
  line-height: 1;
  display: inline-flex;
  align-items: center;
  transition: background 0.15s, color 0.15s;
}

.hero-btn:hover, .hero-btn:focus {
  background: transparent;
  color: var(--c-white);
  outline: none;
}

/* Clip path — slanted bottom edge */
.hero-clip {
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 80px;
  background: var(--c-white);
  clip-path: polygon(0 100%, 100% 0%, 100% 100%);
  z-index: 3;
}

/* ============================================================
   Page Banner (non-home pages)
   ============================================================ */
.page-banner {
  background: var(--c-black);
  color: var(--c-white);
  padding: var(--sp-8) 0 var(--sp-6);
}

.page-banner h1 {
  font-family: var(--ff-mono);
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: var(--fw-bold);
  line-height: 1.2;
  margin-top: var(--sp-2);
  letter-spacing: -0.01em;
}

.page-banner time {
  display: block;
  margin-top: var(--sp-2);
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.55);
}

/* ============================================================
   Breadcrumb
   ============================================================ */
.breadcrumb {
  font-size: 0.8125rem;
  color: rgba(255,255,255,0.5);
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
  margin-bottom: var(--sp-2);
}

.breadcrumb a {
  color: rgba(255,255,255,0.65);
  text-decoration: underline;
}

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

.breadcrumb span {
  color: rgba(255,255,255,0.5);
}

/* Breadcrumb in main content (light bg) */
main .breadcrumb {
  color: var(--c-grey-600);
  margin-bottom: var(--sp-4);
}

main .breadcrumb a {
  color: var(--c-grey-600);
}

main .breadcrumb a:hover {
  color: var(--c-black);
}

main .breadcrumb span {
  color: var(--c-grey-400);
}

/* ============================================================
   Main layout — wrap > section > div (structure contract)
   ============================================================ */
main {
  padding: var(--sp-8) 0;
}

main > .wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--sp-4);
}

main > .wrap > section {
  width: 100%;
}

main > .wrap > section > div {
  width: 100%;
}

/* Content + aside layout: aside LEFT, content RIGHT */
.content-with-aside {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: var(--sp-8);
  align-items: start;
}

/* ============================================================
   Aside / Sidebar
   ============================================================ */
.sidebar {
  position: sticky;
  top: 120px;
}

.sidebar-inner {
  border: var(--border);
  padding: var(--sp-3);
}

.sidebar-inner small {
  display: block;
  font-size: 0.6875rem;
  font-weight: var(--fw-bold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-grey-400);
  margin-bottom: var(--sp-1);
}

.sidebar-inner h3 {
  font-family: var(--ff-mono);
  font-size: 1rem;
  font-weight: var(--fw-bold);
  margin-bottom: var(--sp-3);
  border-bottom: var(--border);
  padding-bottom: var(--sp-2);
}

.sidebar-inner ul {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-inner ul li a {
  display: block;
  font-size: 0.875rem;
  padding: 6px var(--sp-1);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: border-color 0.12s, padding-left 0.12s;
}

.sidebar-inner ul li a:hover,
.sidebar-inner ul li a:focus {
  border-left-color: var(--c-black);
  padding-left: var(--sp-2);
  outline: none;
}

/* ============================================================
   Content Main
   ============================================================ */
.content-main {
  min-width: 0;
}

.content-main h1 {
  font-family: var(--ff-mono);
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  font-weight: var(--fw-bold);
  line-height: 1.2;
  margin-bottom: var(--sp-3);
  letter-spacing: -0.01em;
}

.meta-date {
  font-size: 0.8125rem;
  color: var(--c-grey-400);
  margin-bottom: var(--sp-4);
  font-family: var(--ff-mono);
}

/* ============================================================
   Prose (rich text content from page.content)
   ============================================================ */
.prose {
  font-size: 1rem;
  line-height: 1.75;
}

.prose h2 {
  font-family: var(--ff-mono);
  font-size: 1.375rem;
  font-weight: var(--fw-bold);
  margin-top: var(--sp-6);
  margin-bottom: var(--sp-2);
  padding-top: var(--sp-3);
  border-top: 2px solid var(--c-black);
}

.prose h3 {
  font-size: 1.125rem;
  font-weight: var(--fw-bold);
  margin-top: var(--sp-4);
  margin-bottom: var(--sp-2);
}

.prose p {
  margin-bottom: var(--sp-3);
}

.prose ul, .prose ol {
  margin-bottom: var(--sp-3);
  padding-left: var(--sp-3);
}

.prose ul li {
  list-style: square;
  margin-bottom: var(--sp-1);
}

.prose ol li {
  list-style: decimal;
  margin-bottom: var(--sp-1);
}

.prose a {
  font-weight: var(--fw-bold);
  color: var(--c-black);
}

.prose blockquote {
  border-left: 4px solid var(--c-black);
  padding-left: var(--sp-3);
  margin: var(--sp-4) 0;
  color: var(--c-grey-600);
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--sp-4);
  font-size: 0.9375rem;
}

.prose th, .prose td {
  border: var(--border);
  padding: var(--sp-2) var(--sp-3);
  text-align: left;
}

.prose th {
  background: var(--c-black);
  color: var(--c-white);
  font-weight: var(--fw-bold);
}

.prose tr:nth-child(even) td {
  background: var(--c-grey-100);
}

/* ============================================================
   small eyebrow before h2/h3 (structural contract)
   ============================================================ */
small + h2,
small + h3 {
  margin-top: var(--sp-1);
}

section > .grid-container > small,
.home-rankings small,
.home-compares small {
  display: block;
  font-size: 0.6875rem;
  font-weight: var(--fw-bold);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--c-grey-400);
  margin-bottom: var(--sp-1);
}

/* ============================================================
   Home — content section
   ============================================================ */
.home-content-section {
  margin-bottom: var(--sp-8);
}

.home-content-section > div {
  max-width: 800px;
}

.home-prose {
  border-top: 2px solid var(--c-black);
  padding-top: var(--sp-4);
}

/* ============================================================
   Home — Ranking list (ul > li > div — structure contract)
   ============================================================ */
.home-rankings,
.home-compares {
  padding: var(--sp-10) 0;
  border-top: var(--border);
}

.home-rankings h2,
.home-compares h2 {
  font-family: var(--ff-mono);
  font-size: 1.75rem;
  font-weight: var(--fw-bold);
  margin-bottom: var(--sp-6);
}

.ranking-list,
.compare-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-4);
}

.ranking-list > li,
.compare-list > li {
  display: block;
}

.rank-card,
.compare-card {
  border: var(--border);
  padding: var(--sp-4);
  height: 100%;
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
  transition: transform 0.15s, box-shadow 0.15s;
}

.rank-card:hover,
.compare-card:hover {
  transform: translateY(-2px);
  box-shadow: 4px 4px 0 var(--c-black);
}

.rank-card h3,
.compare-card h3 {
  font-size: 1.0625rem;
  font-weight: var(--fw-bold);
}

.rank-card h3 a,
.compare-card h3 a {
  text-decoration: none;
  color: var(--c-black);
}

.rank-card h3 a:hover,
.compare-card h3 a:hover {
  text-decoration: underline;
}

.rank-card p,
.compare-card p {
  font-size: 0.875rem;
  color: var(--c-grey-600);
  flex-grow: 1;
}

.rank-card .sub-links {
  display: flex;
  flex-direction: column;
  gap: 4px;
  border-top: 1px solid var(--c-grey-200);
  padding-top: var(--sp-2);
}

.rank-card .sub-links li a {
  font-size: 0.8125rem;
  color: var(--c-grey-600);
}

.card-link {
  font-size: 0.8125rem;
  font-weight: var(--fw-bold);
  text-decoration: none;
  letter-spacing: 0.03em;
  color: var(--c-black);
  margin-top: auto;
  display: inline-block;
}

.card-link:hover {
  text-decoration: underline;
}

/* ============================================================
   Ranking page — review items (ul > li > div structure)
   ============================================================ */
.review-items {
  margin-top: var(--sp-6);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}

.review-items > li {
  display: block;
}

.review-item {
  display: grid;
  grid-template-columns: 56px 1fr auto;
  gap: var(--sp-3);
  align-items: start;
  border: var(--border);
  padding: var(--sp-3) var(--sp-4);
  transition: transform 0.15s, box-shadow 0.15s;
}

.review-item:hover {
  transform: translateX(4px);
  box-shadow: -4px 0 0 var(--c-black);
}

.rank-num {
  font-family: var(--ff-mono);
  font-size: 1.75rem;
  font-weight: var(--fw-bold);
  color: var(--c-grey-200);
  line-height: 1;
  padding-top: 4px;
}

.review-item-body h3 {
  font-size: 1.0625rem;
  font-weight: var(--fw-bold);
  margin-bottom: var(--sp-1);
}

.review-item-body h3 a {
  text-decoration: none;
  color: var(--c-black);
}

.review-item-body h3 a:hover {
  text-decoration: underline;
}

.review-item-body p {
  font-size: 0.875rem;
  color: var(--c-grey-600);
}

.review-item-body time {
  display: block;
  font-size: 0.75rem;
  color: var(--c-grey-400);
  margin-top: var(--sp-1);
}

/* ============================================================
   Review page hero
   ============================================================ */
.review-hero {
  margin-bottom: var(--sp-5);
  border: var(--border);
  overflow: hidden;
}

.review-hero-img {
  width: 100%;
  max-height: 400px;
  object-fit: cover;
}

/* ============================================================
   Compare prose — table emphasis
   ============================================================ */
.compare-prose table th {
  background: var(--c-black);
  color: var(--c-white);
}

/* ============================================================
   FAQ prose — definition-style
   ============================================================ */
.faq-prose h2 {
  font-size: 1.125rem;
  margin-top: var(--sp-5);
  background: var(--c-grey-100);
  padding: var(--sp-2) var(--sp-3);
  border-left: 4px solid var(--c-black);
  border-top: none;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  background: var(--c-black);
  color: var(--c-white);
  margin-top: var(--sp-10);
}

/* CTA block */
.footer-cta {
  padding: var(--sp-10) 0;
  border-bottom: 1px solid rgba(255,255,255,0.15);
}

.cta-inner {
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

.cta-label {
  font-size: 0.75rem;
  font-weight: var(--fw-bold);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
}

.footer-cta h2 {
  font-family: var(--ff-mono);
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: var(--fw-bold);
  color: var(--c-white);
  line-height: 1.2;
}

.cta-btn {
  display: inline-flex;
  align-items: center;
  background: var(--c-white);
  color: var(--c-black);
  font-family: var(--ff-mono);
  font-weight: var(--fw-bold);
  font-size: 0.9375rem;
  padding: var(--sp-2) var(--sp-5);
  text-decoration: none;
  border: 2px solid var(--c-white);
  min-height: 48px;
  align-self: flex-start;
  margin-top: var(--sp-3);
  transition: background 0.15s, color 0.15s;
}

.cta-btn:hover, .cta-btn:focus {
  background: transparent;
  color: var(--c-white);
  outline: none;
}

/* Footer main */
.footer-main {
  padding: var(--sp-8) 0 var(--sp-4);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-8);
  margin-bottom: var(--sp-6);
}

.footer-brand-col address {
  font-style: normal;
  font-size: 0.9375rem;
  line-height: 1.6;
  color: rgba(255,255,255,0.8);
}

.footer-brand-col address strong {
  display: block;
  font-size: 1.0625rem;
  color: var(--c-white);
  margin-bottom: var(--sp-2);
}

.footer-links-col ul {
  display: flex;
  flex-direction: column;
  gap: var(--sp-1);
}

.footer-links-col ul li a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.7);
  text-decoration: none;
  padding: 4px 0;
  display: block;
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: color 0.12s;
}

.footer-links-col ul li a:hover,
.footer-links-col ul li a:focus {
  color: var(--c-white);
  outline: none;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.15);
  padding-top: var(--sp-3);
}

.footer-bottom p {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.4);
}

.footer-bottom a {
  color: rgba(255,255,255,0.6);
}

/* ============================================================
   Scroll Reveal (JS class applied)
   ============================================================ */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}

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

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ============================================================
   Responsive: Tablet (max 960px)
   ============================================================ */
@media (max-width: 960px) {
  .content-with-aside {
    grid-template-columns: 200px 1fr;
    gap: var(--sp-5);
  }

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

  .header-search input[type="search"] {
    width: 160px;
  }
}

/* ============================================================
   Responsive: Mobile (max 640px)
   ============================================================ */
@media (max-width: 640px) {
  :root {
    --sp-4: 24px;
    --sp-8: 48px;
    --sp-10: 56px;
    --sp-12: 64px;
  }

  .grid-container {
    padding-left: var(--sp-3);
    padding-right: var(--sp-3);
  }

  .brand-text {
    font-size: 0.9375rem;
  }

  .header-search {
    display: none;
  }

  .header-nav nav > p > a {
    font-size: 0.75rem;
    padding: var(--sp-2) var(--sp-2);
  }

  .hero {
    min-height: 100vh;
  }

  .hero h1 {
    font-size: 1.75rem;
  }

  .hero-clip {
    height: 48px;
  }

  .content-with-aside {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
    order: 2;
  }

  .content-main {
    order: 1;
  }

  .ranking-list,
  .compare-list {
    grid-template-columns: 1fr;
  }

  .review-item {
    grid-template-columns: 44px 1fr;
  }

  .review-item .card-link {
    grid-column: 1 / -1;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-5);
  }

  .page-banner {
    padding: var(--sp-6) 0 var(--sp-4);
  }
}

/* ============================================================
   Hover micro-interactions
   ============================================================ */
@media (prefers-reduced-motion: no-preference) {
  .rank-card,
  .compare-card,
  .review-item {
    will-change: transform;
  }
}