/* ===========================
   CSS Variables & Common Styles
   =========================== */

:root {
    /* Colors */
    --color-text-primary: #525252;
    --color-text-secondary: #686963;
    --color-accent-dark: #5b5c57;
    --color-accent-warm: #e9cabc;
    --color-bg: #f5f0eb;
    --color-white: #ffffff;
    --color-border: #ddd;

    /* Typography */
    --font-heading: 'Zen Old Mincho', 'YuMincho', 'Yu Mincho', serif;
    --font-body: 'Meiryo', 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', sans-serif;

    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 15px;
    --spacing-md: 30px;
    --spacing-lg: 50px;
    --spacing-xl: 80px;

    /* Layout */
    --max-width: 1100px;
    --max-width-narrow: 800px;
}

/* Base */
body {
    font-family: var(--font-body);
    font-size: 16px;
    font-weight: 500;
    color: var(--color-text-primary);
    background-color: var(--color-bg);
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-text-primary);
}

h1 {
    font-size: 36px;
}

h2 {
    font-size: 28px;
}

h3 {
    font-size: 22px;
}

h4 {
    font-size: 18px;
}

/* Links */
a {
    transition: opacity 0.3s ease;
}

a:hover {
    opacity: 0.7;
}

/* Container */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 25px;
}

.container-narrow {
    max-width: var(--max-width-narrow);
    margin: 0 auto;
    padding: 0 25px;
}

/* Skip Links */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--color-accent-dark);
    color: var(--color-white);
    padding: 8px 16px;
    z-index: 1000;
    font-size: 14px;
}

.skip-link:focus {
    top: 0;
}

/* Section */
.section {
    padding: var(--spacing-xl) 0;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 28px;
    text-align: center;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text-primary);
}

/* Breadcrumb */
.breadcrumb {
    padding: var(--spacing-sm) 0;
    font-size: 13px;
    color: var(--color-text-secondary);
}

.breadcrumb ol {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
    align-items: center;
}

.breadcrumb li:not(:last-child)::after {
    content: '>';
    margin-left: 4px;
    color: var(--color-text-secondary);
}

.breadcrumb a {
    color: var(--color-text-secondary);
}

.breadcrumb a:hover {
    text-decoration: underline;
}

/* Button */
.btn {
    display: inline-block;
    padding: 14px 40px;
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 500;
    text-align: center;
    border-radius: 4px;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: var(--color-accent-dark);
    color: var(--color-white);
}

.btn-primary:hover {
    opacity: 0.8;
}

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

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

/* Divider */
.divider {
    border: none;
    border-top: 1px solid var(--color-border);
    margin: var(--spacing-lg) 0;
}

/* Screen Reader Only */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* ===========================
   Responsive
   =========================== */

@media (max-width: 991px) {
    h1 { font-size: 28px; }
    h2 { font-size: 24px; }
    h3 { font-size: 20px; }

    .section {
        padding: var(--spacing-lg) 0;
    }
}

@media (max-width: 767px) {
    h1 { font-size: 24px; }
    h2 { font-size: 22px; }
    h3 { font-size: 18px; }

    body {
        font-size: 15px;
    }

    .container,
    .container-narrow {
        padding: 0 20px;
    }
}

@media (max-width: 478px) {
    h1 { font-size: 22px; }
    h2 { font-size: 20px; }
}