*, *::before, *::after {
  box-sizing: border-box;
}

/* ========== デザイントークン ========== */
:root {
  --color-primary: #7c6aed;
  --color-primary-dark: color-mix(in oklch, var(--color-primary), black 15%);
  --color-accent: #c084fc;

  --color-bg: #ffffff;
  --color-surface: #f9fafb;
  --color-text: #1f2937;
  --color-text-muted: #6b7280;
  --color-border: #e5e7eb;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.12);

  --radius: 0.5rem;
  --radius-lg: 1rem;

  --content-max: 1100px;
}

[data-theme="dark"] {
  --color-bg: #0f172a;
  --color-surface: #1e293b;
  --color-text: #f1f5f9;
  --color-text-muted: #94a3b8;
  --color-border: #334155;
}

/* ========== ベース ========== */
body {
  margin: 0;
  font-family: system-ui, -apple-system, sans-serif;
  line-height: 1.7;
  background: var(--color-bg);
  color: var(--color-text);
  transition: background 0.3s, color 0.3s;
}

.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 1.5rem;
}



h1, h2 {
  line-height: 1.3;
}

a {
  color: var(--color-primary);
  &:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
    border-radius: 2px;
  }
}

/* ========== ヘッダー ========== */
.site-header {
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--color-bg) 90%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
  z-index: 100;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 4rem;
}

.logo {
  font-size: 1.25rem;
  font-weight: bold;
  color: var(--color-text);
  text-decoration: none;
}

.nav-list {
  display: none;
  list-style: none;
  gap: 1.5rem;
  margin: 0;
  padding: 0;

  & a {
    color: var(--color-text);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;

    &:hover {
      color: var(--color-primary);
    }
  }
}

@media (min-width: 48rem) {
  .nav-list {
    display: flex;
  }
}

.theme-toggle {
  background: transparent;
  border: 1px solid var(--color-border);
  color: var(--color-text);
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 1.1rem;

  &:hover {
    background: var(--color-surface);
  }
}

/* ========== Hero ========== */
.hero {
  padding: clamp(2rem, 6vw, 4rem) 0;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: white;
  text-align: center;
}

.hero-greeting {
  font-size: 1.2rem;
  margin: 0;
  opacity: 0.9;
}

.hero-title {
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  margin: 0.5rem 0;
}

.hero-subtitle {
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  margin: 0;
  opacity: 0.95;
}

.hero-description {
  margin: 1.5rem auto;
  max-width: 32rem;
  font-size: 1.05rem;
  opacity: 0.9;
}
/* ========== セクション共通 ========== */
.section {
  padding: clamp(3rem, 8vw, 5rem) 0;
}

.section-alt {
  background: var(--color-surface);
}

.section h2 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  margin: 0 0 0.5rem;
  text-align: center;
}

.section-intro {
  text-align: center;
  color: var(--color-text-muted);
  margin: 0 0 2.5rem;
}

/* ========== 自己紹介 ========== */
.intro-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  max-width: 38rem;
  margin: 2rem auto 0;
  text-align: center;
}

.intro-text p {
  margin: 0 0 1rem;
}

.intro-text p:last-child {
  margin-bottom: 0;
}

.avatar {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  border: 4px solid var(--color-primary);
  box-shadow: var(--shadow-lg);
  object-fit: cover;
}
/* ========== Footer ========== */
.site-footer {
  background: #1e293b;
  color: #f1f5f9;
  padding: 2rem 0;
  text-align: center;
}

.social-links {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  list-style: none;
  padding: 0;
  margin: 0 0 1rem;

  & a {
    color: white;
    text-decoration: none;

    &:hover {
      color: var(--color-primary);
    }
  }
}