/*
Theme Name: Shikakusankaku Log
Theme URI: https://sankakushikaku.co.jp/
Description: 合同会社さんかくしかく Practice Log 用カスタムテーマ
Author: 合同会社さんかくしかく
Version: 1.0.0
Text Domain: shikakusankaku-log
*/

/* ============================================================
   Design Tokens (from ver2/src/style.css)
   ============================================================ */
:root {
  --color-white: #ffffff;
  --color-black: #1a1a1a;
  --color-gray-light: #f5f5f5;
  --color-gray: #888888;
  --color-navy: #0F172A;

  --font-heading: 'Zen Kaku Gothic Antique', 'Yu Gothic', 'Hiragino Kaku Gothic ProN', sans-serif;
  --font-body: 'Inter', 'Noto Sans JP', sans-serif;

  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 2rem;
  --space-lg: 4rem;
  --space-xl: 8rem;
  --space-xxl: 12rem;
}

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

body {
  font-family: var(--font-body);
  color: var(--color-black);
  background-color: var(--color-white);
  line-height: 1.8;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 500;
  line-height: 1.4;
  letter-spacing: 0.05em;
}

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

a:hover { opacity: 0.7; }

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

/* ============================================================
   Layout
   ============================================================ */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section {
  padding: var(--space-xxl) 0;
}

@media (max-width: 768px) {
  .section { padding: var(--space-xl) 0; }
}

/* ============================================================
   Utilities
   ============================================================ */
.text-center { text-align: center; }
.text-gray { color: var(--color-gray); }
.text-navy { color: var(--color-navy); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-lg { margin-bottom: var(--space-lg); }
.bg-gray { background-color: var(--color-gray-light); }

/* ============================================================
   Header
   ============================================================ */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: var(--space-md) 0;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  z-index: 100;
  transition: transform 0.3s ease, padding 0.3s ease;
}

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

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

.header-logo-img {
  height: 48px;
  width: auto;
  display: block;
  transition: height 0.3s ease;
}

@media (max-width: 1024px) { .header-logo-img { height: 38px; } }
@media (max-width: 768px)  { .header-logo-img { height: 32px; } }
@media (max-width: 480px)  { .header-logo-img { height: 26px; } }

.nav {
  display: flex;
  gap: var(--space-md);
}

.nav a {
  font-size: 0.875rem;
  letter-spacing: 0.05em;
  font-weight: 500;
}

/* Hamburger */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
  z-index: 101;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-black);
  margin: 5px 0;
  transition: all 0.3s ease;
}

@media (max-width: 768px) {
  .hamburger { display: block; }
  .nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 100%;
    height: 100vh;
    background-color: rgba(255, 255, 255, 0.98);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    transition: right 0.3s ease;
    z-index: 100;
  }
  .nav.is-open { right: 0; }
  .hamburger.is-active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .hamburger.is-active span:nth-child(2) { opacity: 0; }
  .hamburger.is-active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
  .nav a { font-size: 1.25rem; padding: 1rem; }
}

/* ============================================================
   Button
   ============================================================ */
.btn {
  display: inline-block;
  padding: 1rem 3rem;
  background-color: var(--color-navy);
  color: var(--color-white);
  border: 1px solid var(--color-navy);
  font-family: var(--font-heading);
  font-size: 0.9rem;
  letter-spacing: 0.1em;
  transition: all 0.3s ease;
  cursor: pointer;
}

.btn:hover {
  background-color: var(--color-white);
  color: var(--color-navy);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-black);
  border: 1px solid var(--color-black);
}

.btn-outline:hover {
  background-color: var(--color-black);
  color: var(--color-white);
}

/* ============================================================
   Footer
   ============================================================ */
.footer {
  padding: var(--space-lg) 0;
  background-color: var(--color-gray-light);
  text-align: center;
}

.footer-nav {
  margin-bottom: var(--space-md);
  display: flex;
  justify-content: center;
  gap: var(--space-md);
}

.footer-nav a { font-size: 0.875rem; }

.copyright {
  font-size: 0.75rem;
  color: var(--color-gray);
  letter-spacing: 0.05em;
}

/* ============================================================
   Page Header
   ============================================================ */
.page-header {
  padding: var(--space-xxl) 0 var(--space-lg);
  background-color: var(--color-gray-light);
  text-align: center;
}

.page-title { font-size: 3rem; }

@media (max-width: 768px) {
  .page-title { font-size: 2rem; }
}

/* ============================================================
   Section Title
   ============================================================ */
.section-title {
  font-size: 2.5rem;
  margin-bottom: var(--space-lg);
  font-weight: 400;
}

@media (max-width: 768px) {
  .section-title {
    font-size: 2rem;
    margin-bottom: var(--space-md);
  }
}

/* ============================================================
   Practice Log Grid & Cards
   ============================================================ */
.log-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-md);
}

.log-card {
  display: block;
  background-color: var(--color-gray-light);
  padding: var(--space-md);
  transition: background-color 0.3s ease, color 0.3s ease;
}

.log-card:hover {
  background-color: var(--color-navy);
  color: var(--color-white);
  opacity: 1;
}

.log-card:hover .log-meta,
.log-card:hover .log-excerpt {
  color: rgba(255, 255, 255, 0.8);
}

.log-cat {
  display: inline-block;
  padding: 0.2rem 0.8rem;
  font-size: 0.75rem;
  font-weight: 700;
  margin-bottom: var(--space-sm);
  background-color: var(--color-white);
  color: var(--color-black);
}

.log-meta {
  font-size: 0.8rem;
  color: var(--color-gray);
  margin-bottom: var(--space-xs);
}

.log-title {
  font-size: 1.1rem;
  line-height: 1.5;
}

.log-excerpt {
  font-size: 0.875rem;
  color: var(--color-gray);
  margin-top: var(--space-sm);
  line-height: 1.7;
}

/* Category Filter */
.category-filter {
  display: flex;
  justify-content: center;
  gap: var(--space-sm);
  flex-wrap: wrap;
  margin-bottom: var(--space-lg);
}

.category-filter a {
  padding: 0.5rem 1.5rem;
  border: 1px solid transparent;
  font-size: 0.875rem;
  transition: all 0.3s ease;
}

.category-filter a.is-active,
.category-filter a:hover {
  border-color: var(--color-black);
}

/* Pagination */
.pagination {
  display: flex;
  justify-content: center;
  gap: 0.25rem;
  margin-top: var(--space-lg);
}

.pagination a,
.pagination span {
  display: inline-block;
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

.pagination .current {
  border: 1px solid var(--color-black);
}

.pagination a {
  color: var(--color-gray);
}

/* ============================================================
   Single Article
   ============================================================ */
.article-header {
  text-align: center;
  padding: var(--space-xl) 0 var(--space-lg);
  border-bottom: 1px solid var(--color-gray-light);
  margin-bottom: var(--space-lg);
}

.article-title {
  font-size: 2.5rem;
  margin: var(--space-md) 0;
  line-height: 1.4;
}

@media (max-width: 768px) {
  .article-title { font-size: 1.8rem; }
}

.article-thumbnail {
  max-width: 760px;
  margin: 0 auto var(--space-lg);
}

.article-thumbnail img {
  width: 100%;
  height: auto;
}

.article-content {
  max-width: 760px;
  margin: 0 auto;
  font-size: 1.05rem;
  line-height: 2;
}

.article-content h2 {
  font-size: 1.8rem;
  margin: var(--space-lg) 0 var(--space-sm);
  padding-bottom: var(--space-xs);
  border-bottom: 2px solid var(--color-navy);
}

.article-content h3 {
  font-size: 1.4rem;
  margin: var(--space-md) 0 var(--space-xs);
}

.article-content p {
  margin-bottom: var(--space-md);
}

.article-content img {
  margin: var(--space-lg) 0;
  width: 100%;
  height: auto;
}

.article-content ul,
.article-content ol {
  margin: var(--space-sm) 0 var(--space-md) var(--space-md);
}

.article-content li {
  margin-bottom: var(--space-xs);
}

.article-content blockquote {
  border-left: 3px solid var(--color-navy);
  padding-left: var(--space-md);
  margin: var(--space-md) 0;
  color: var(--color-gray);
  font-style: italic;
}

.article-footer {
  max-width: 760px;
  margin: var(--space-xxl) auto var(--space-lg);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-gray-light);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-md);
}

.share-links {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.share-links span {
  color: var(--color-gray);
  font-size: 0.875rem;
}

/* ============================================================
   Fade-in Animation
   ============================================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}