/* ===== Base ===== */

:root {
  --accent: #2c3e50;
  --accent-soft: #5c6b77;
  --bg: #f3f5f7;
  --card-bg: #ffffff;
  --border: #e3e6ea;
}

body {
  font-family: -apple-system, BlinkMacSystemFont,
               "Hiragino Kaku Gothic ProN",
               "Yu Gothic", "Meiryo", sans-serif;
  background: var(--bg);
  color: #2a2a2a;
  margin: 0;
  line-height: 1.9;
  letter-spacing: 0.02em;
}

.container {
  max-width: 760px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

/* ===== Navigation ===== */

.main-nav {
  display: flex;
  gap: 1.8rem;
  margin-bottom: 2.5rem;
  font-size: 0.92rem;
  border-bottom: 1px solid var(--border);
  padding-bottom: 0.8rem;
}

.main-nav a {
  text-decoration: none;
  color: var(--accent-soft);
  transition: all 0.2s ease;
}

.main-nav a:hover {
  color: var(--accent);
}

.main-nav a.active {
  font-weight: 600;
  color: var(--accent);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 3px;
}

/* ===== Headings ===== */

h1 {
  font-weight: 600;
  font-size: 1.5rem;
  margin-bottom: 1.8rem;
  letter-spacing: 0.05em;
}

h2 {
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 1rem;
}

/* ===== Entries ===== */

.entry {
  background: var(--card-bg);
  padding: 2rem 2.2rem;
  border-radius: 14px;
  box-shadow: 0 6px 20px rgba(0,0,0,0.04);
  margin-bottom: 3.5rem;
  transition: transform 0.2s ease;
}

.entry:hover {
  transform: translateY(-2px);
}

.entry h2 {
  margin-top: 0;
  color: var(--accent);
}

/* ===== Links ===== */

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

/* ===== Navigation Blocks ===== */

.nav {
  margin: 2rem 0;
  text-align: center;
  font-size: 0.95rem;
}

.nav a {
  margin: 0 1rem;
  color: var(--accent-soft);
}

.nav a:hover {
  color: var(--accent);
}

/* ===== Selectors ===== */

.month-selector,
.week-selector {
  margin: 1rem 0 2.5rem 0;
}

.month-selector select,
.week-selector input {
  padding: 6px 8px;
  font-size: 0.95rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: #fff;
}

.month-selector button {
  padding: 6px 12px;
  font-size: 0.9rem;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #fff;
  cursor: pointer;
  transition: background 0.2s ease;
}

.month-selector button:hover {
  background: #f0f2f4;
}

/* ===== Footer ===== */

.footer {
  text-align: center;
  color: #999;
  font-size: 0.85rem;
  margin-top: 5rem;
}