/**
 * Shard - メインスタイルシート (最適化版)
 */

@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;700&family=Poppins:wght@400;600&display=swap');

:root {
    --primary: #5d5dff;
    --primary-light: #7577ff;
    --primary-dark: #4a47ff;
    --secondary: #33363a;
    --accent: #4f46e5;
    --light: #f8fafc;
    --dark: #1e293b;
    --gray: #64748b;
    --gray-light: #e2e8f0;
    --gray-dark: #334155;
    --gradient-primary: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    --gradient-blue: linear-gradient(135deg, #4cc9f0 0%, #4361ee 100%);
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #f0f9ff;
    --dark-color: #1e293b;
    --text-color: #334155;
    --light-color: #f8fafc;
    --border-color: #e2e8f0;
    --success-color: #10b981;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    --transition: all 0.3s ease;
    --border-radius: 8px;
}

* {margin: 0; padding: 0; box-sizing: border-box;}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    font-size: 1rem;
    color: var(--dark);
    background-color: #fff;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    margin-bottom: 1rem;
    font-weight: 700;
    line-height: 1.2;
    color: var(--dark);
}

h1, .h1 {font-size: 2.5rem;}
h2, .h2 {font-size: 2rem;}
h3, .h3 {font-size: 1.75rem;}
h4, .h4 {font-size: 1.5rem;}
h5, .h5 {font-size: 1.25rem;}
h6, .h6 {font-size: 1rem;}

p {margin-bottom: 1rem;}
a {color: var(--primary-color); text-decoration: none; transition: var(--transition);}
a:hover {color: var(--primary-dark);}
img {max-width: 100%; height: auto;}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

.row {
    display: flex;
    flex-wrap: wrap;
    margin: -15px;
}

.col-lg-6 {width: 100%; padding: 15px;}
@media (min-width: 992px) {.col-lg-6 {width: 50%;}}

/* ユーティリティクラス */
.align-items-center {align-items: center;}
.mb-0 {margin-bottom: 0 !important;}
.mb-1 {margin-bottom: 0.25rem !important;}
.mb-2 {margin-bottom: 0.5rem !important;}
.mb-3 {margin-bottom: 1rem !important;}
.mb-4 {margin-bottom: 1.5rem !important;}
.mb-5 {margin-bottom: 3rem !important;}
.mt-3 {margin-top: 1rem !important;}
.mt-4 {margin-top: 1.5rem !important;}
.mt-5 {margin-top: 3rem !important;}
.me-3 {margin-right: 1rem !important;}
.me-4 {margin-right: 1.5rem !important;}
.py-4 {padding-top: 1.5rem !important; padding-bottom: 1.5rem !important;}
.p-4 {padding: 1.5rem !important;}
.text-center {text-align: center;}
.text-danger {color: var(--danger-color);}
.w-100 {width: 100% !important;}
.fw-bold {font-weight: 700;}
.img-fluid {max-width: 100%; height: auto;}
.rounded {border-radius: var(--border-radius);}
.d-flex {display: flex;}
.flex-column {flex-direction: column;}

/* ヘッダー */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    transition: var(--transition);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
}

.logo {display: flex; align-items: center;}
.logo img {height: 40px; margin-right: 0.5rem;}
.navbar-brand {font-size: 1.5rem; font-weight: 700; color: var(--dark-color);}
.navbar-brand:hover {color: var(--primary-color);}
.navbar {display: flex; align-items: center;}
.nav-menu {display: flex; list-style: none; margin: 0; padding: 0;}
.nav-item {margin-left: 1.5rem;}

.nav-link {
    color: var(--text-color);
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
}

.nav-link:hover {color: var(--primary-color);}
.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

.nav-link:hover::after {width: 100%;}
.nav-link.active {color: var(--primary-color);}
.nav-link.active::after {width: 100%;}

.hamburger {display: none; cursor: pointer;}
.hamburger span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--dark-color);
    margin: 5px 0;
    transition: var(--transition);
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: var(--transition);
        box-shadow: 0 10px 15px rgba(0, 0, 0, 0.1);
        padding: 2rem 0;
    }
    .nav-menu.active {left: 0;}
    .nav-item {margin: 1rem 0;}
    .hamburger {display: block;}
    .hamburger.active span:nth-child(2) {opacity: 0;}
    .hamburger.active span:nth-child(1) {transform: translateY(8px) rotate(45deg);}
    .hamburger.active span:nth-child(3) {transform: translateY(-8px) rotate(-45deg);}
}

/* ボタン */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 30px;
    text-align: center;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
}

.btn-primary {background-color: var(--primary-color); color: white;}
.btn-primary:hover {background-color: var(--primary-dark); color: white;}
.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}
.btn-outline:hover {background-color: var(--primary-color); color: white;}
.btn-sm {padding: 0.5rem 1rem; font-size: 0.875rem;}

/* フッター */
.footer {
    background-color: var(--dark-color);
    color: white;
    padding: 3rem 0 1rem;
}

/* レスポンシブスタイル */
@media (max-width: 1200px) {
    .container {max-width: 960px;}
    html {font-size: 15px;}
}

@media (max-width: 992px) {
    .container {max-width: 720px;}
    html {font-size: 14px;}
}

@media (max-width: 768px) {
    .container {max-width: 540px;}
    html {font-size: 14px;}
    section {padding: 3rem 0;}
}

@media (max-width: 576px) {
    .container {max-width: 100%; padding: 0 1.5rem;}
    html {font-size: 14px;}
}

/* 言語ガイドレイアウト */
.language-guide-content {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
}

.language-guide-main {flex: 1 1 65%; min-width: 0;}
.language-guide-sidebar {flex: 0 1 30%; min-width: 250px;}

@media (max-width: 992px) {
    .language-guide-content {flex-direction: column;}
    .language-guide-main, .language-guide-sidebar {flex: 1 1 100%;}
}

/* 目次スタイル */
.toc-wrapper {
    margin-bottom: 2rem;
    position: static !important; /* 固定位置を無効化 */
}
.toc-list {
    list-style: none; 
    padding-left: 0;
    position: static !important; /* 固定位置を無効化 */
}
.toc-list .nav-link {
    padding: 0.5rem 1rem;
    border-left: 2px solid var(--gray-light);
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}
.toc-list .nav-link:hover,
.toc-list .nav-link.active {
    border-left: 2px solid var(--primary);
    background-color: rgba(93, 93, 255, 0.05);
}