:root {
  --blue-light: #00b3ec;
  --blue-mid: #0068b6;
  --blue-deep: #1d2087;
  --text: #222;
}

* {
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Meiryo", sans-serif;
  margin: 0;
  color: var(--text);
  line-height: 1.7;
  background: linear-gradient(160deg, var(--blue-light) 0%, var(--blue-mid) 40%, var(--blue-deep) 100%);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding-top: 62px; /* navbar分 */
}

/* --- Navbar --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 62px;
  background: rgba(0, 50, 90, 0.55);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  z-index: 100;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.nav-left {
  display: flex;
  align-items: center;
  gap: 10px;
}
.logo-box {
  width: 34px;
  height: 34px;
  border: 2px solid #fff;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
  font-size: 0.78rem;
  letter-spacing: -0.03em;
}
.nav-title {
  color: #fff;
  font-weight: 600;
  letter-spacing: .02em;
}
.nav-right a {
  color: #fff;
  text-decoration: none;
  margin-left: 18px;
  font-size: 0.9rem;
  opacity: 0.9;
  transition: opacity 0.2s ease;
}
.nav-right a:hover {
  opacity: 1;
}

header {
  text-align: center;
  color: #fff;
  padding: 46px 20px 30px;
}
header h1 {
  font-size: 2.0rem;
  margin: 0;
  letter-spacing: 0.05em;
}
header p {
  font-size: 1rem;
  opacity: 0.9;
  margin-top: 6px;
}

.container {
  display: grid;
  gap: 40px;
  max-width: 960px;
  margin: 0 auto;
  padding: 20px 20px 80px;
}

@media (min-width: 720px) {
  .container {
    grid-template-columns: 1fr 1fr;
  }
}

.card {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 16px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
  padding: 30px 26px 36px;
  text-align: left;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  backdrop-filter: blur(6px);
  animation: fadeInUp 1s ease both;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 30px rgba(0, 0, 0, 0.25);
}

.card h2 {
  font-size: 1.8rem;
  margin: 0 0 8px;
}

.card p {
  margin: 12px 0 24px;
}

.card img.hero {
  width: 100%;
  max-width: 340px;
  border-radius: 12px;
  margin: 10px 0 20px;
}

.paper-card {
  display: block;
  text-decoration: none;
  color: inherit;
}

.paper-card-inner {
  height: 100%;
  border-radius: 14px;
  border: 1px solid #e5e7eb;
  padding: 20px;
  background: linear-gradient(180deg, #ffffff 0%, #f9fafb 100%);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.paper-card-inner:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
}

.paper-card-header h3 {
  font-size: 1.15rem;
  line-height: 1.4;
  margin: 8px 0 6px;
}

.paper-badge {
  display: inline-block;
  font-size: 0.7rem;
  letter-spacing: 0.05em;
  padding: 4px 8px;
  border-radius: 6px;
  background: #1d2087;
  color: white;
  font-weight: 600;
}

.paper-desc {
  font-size: 0.9rem;
  color: #444;
  margin: 10px 0 12px;
}

.paper-points {
  padding-left: 1.1em;
  font-size: 0.85rem;
  color: #333;
  margin: 0 0 12px;
}

.paper-points li {
  margin-bottom: 4px;
}

.paper-card-footer {
  text-align: right;
  font-size: 0.85rem;
  font-weight: 600;
  color: #0068b6;
}

.link-btn {
  align-self: flex-start;
  background: var(--blue-deep);
  color: #fff;
  padding: 10px 22px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
  transition: background 0.25s ease;
}

.link-btn:hover {
  background: var(--blue-mid);
}

.card[data-mode="sme"] .link-btn {
  background: #2e7d32;
}

.card[data-mode="sme"] .link-btn:hover {
  background: #1b5e20;
}

.fusion h2 span {
  color: var(--blue-light);
}

.lean h2 span {
  color: var(--blue-deep);
}

footer {
  text-align: center;
  padding: 20px 10px 50px;
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
}

@keyframes fadeInUp {
  from {opacity: 0; transform: translateY(20px);}
  to {opacity: 1; transform: translateY(0);}
}

.card:nth-child(1) { animation-delay: 0.2s; }
.card:nth-child(2) { animation-delay: 0.4s; }

/* small screens */
@media (max-width: 540px) {
  .nav-right {
    display: none;
  }
  header {
    padding-top: 34px;
  }
}

/* --- Mode Switch --- */
.mode-switch {
  display: flex;
  justify-content: center;
  gap: 12px;
  padding: 0 20px 20px;
  max-width: 800px;
  margin: 0 auto;
}

.mode-btn {
  flex: 1;
  padding: 10px 20px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.8);
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  backdrop-filter: blur(5px);
}

.mode-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.5);
  color: #fff;
}

.mode-btn.active {
  background: rgba(255, 255, 255, 0.95);
  border-color: rgba(255, 255, 255, 0.95);
  color: var(--blue-deep);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.mode-btn[data-mode="sme"].active {
  background: rgba(232, 245, 233, 0.95);
  border-color: rgba(200, 230, 201, 0.95);
  color: #2e7d32;
}

/* Hide sections based on mode */
.card[data-mode="advanced"] {
  display: flex;
}

.card[data-mode="sme"] {
  display: none;
  background: rgba(232, 245, 233, 0.95); /* Very light green background */
}

body.sme-mode .card[data-mode="advanced"] {
  display: none;
}

body.sme-mode .card[data-mode="sme"] {
  display: flex;
}

/* Paper card mode switching */
.paper-card[data-mode="advanced"] {
  display: block;
}

.paper-card[data-mode="sme"] {
  display: none;
}

body.sme-mode .paper-card[data-mode="advanced"] {
  display: none;
}

body.sme-mode .paper-card[data-mode="sme"] {
  display: block;
}

/* SME mode paper card styling */
.paper-card[data-mode="sme"] .paper-card-inner {
  background: linear-gradient(180deg, rgba(232, 245, 233, 0.95) 0%, rgba(220, 237, 222, 0.95) 100%);
}

.paper-card[data-mode="sme"] .paper-badge {
  background: #2e7d32;
}

.paper-card[data-mode="sme"] .paper-card-footer {
  color: #2e7d32;
}