/* ==========================================================================
   BASE.CSS - 基本スタイル、リセット、CSS変数
   ========================================================================== */

/* ==========================================================================
   1. CSS VARIABLES (デザインシステム)
   ========================================================================== */
:root {
    --color-white: #ffffff;
    --color-primary: #0F172A; /* 深みのある紺色 */
    --color-accent: #C5A059;  /* シャンパンゴールド */
    --color-text-body: #334155;
    --color-text-muted: rgba(15, 23, 42, 0.5);
    --color-bg-ivory: #F9F9FB;
    --color-border: rgba(15, 23, 42, 0.08);
    
    --font-serif: 'Playfair Display', 'Noto Serif JP', serif;
    --font-sans: 'Noto Sans JP', sans-serif;
    
    --spacing-section: 160px;
    --spacing-hero: 160px;
    --transition-main: 1.2s cubic-bezier(0.16, 1, 0.3, 1);
    --transition-fast: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ==========================================================================
   2. BASE STYLES & RESET
   ========================================================================== */
* { 
    margin: 0; 
    padding: 0; 
    box-sizing: border-box; 
}

html { 
    scroll-behavior: smooth; 
}

body {
    font-family: var(--font-sans);
    background-color: var(--color-white);
    color: var(--color-primary);
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
    word-break: break-all;
}

/* 背景テクスチャ */
body::before {
    content: "";
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3BaseFilter id='filter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/baseFilter%3E%3Crect width='100%25' height='100%25' filter='url(%23filter)'/%3E%3C/svg%3E");
    opacity: 0.02;
    pointer-events: none;
    z-index: 9999;
}

/* 基本タイポグラフィ */
h1, h2, h3, h4 { 
    font-family: var(--font-serif); 
    font-weight: 400; 
    line-height: 1.3; 
}

a { 
    text-decoration: none; 
    color: inherit; 
    transition: color var(--transition-fast); 
}

ul, ol { 
    list-style: none; 
}

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

button { 
    cursor: pointer; 
    border: none; 
    background: none; 
    font-family: inherit; 
}

/* コンテナ */
.container {
    max-width: 1300px;
    margin: 0 auto;
    padding: 0 40px;
}

/* Revealアニメーション */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity var(--transition-main), transform var(--transition-main);
}

.reveal.active { 
    opacity: 1; 
    transform: translateY(0); 
}

/* セクション共通スタイル */
.section { 
    padding: var(--spacing-section) 0; 
    position: relative; 
    overflow: hidden; 
}

.section-label {
    display: flex; 
    align-items: center; 
    gap: 16px; 
    margin-bottom: 32px;
    font-size: 10px; 
    font-weight: 700; 
    letter-spacing: 0.5em; 
    text-transform: uppercase; 
    color: var(--color-text-muted);
}

.section-label::before { 
    content: ""; 
    width: 32px; 
    height: 1px; 
    background: var(--color-accent); 
    opacity: 0.5; 
}

.section-title { 
    font-size: clamp(32px, 5vw, 48px); 
    margin-bottom: 32px; 
    color: var(--color-primary); 
}

.section-title span { 
    color: var(--color-accent); 
    font-style: italic; 
    font-weight: 300; 
}

.section-intro { 
    font-size: 18px; 
    color: var(--color-text-body); 
    max-width: 800px; 
    margin-bottom: 80px; 
    font-weight: 300; 
}

/* レスポンシブ */
@media (max-width: 768px) {
    .container { 
        padding: 0 24px; 
    }
}