:root {
  --primary-color: #004ea1; /* SoftBankブルー */
  --secondary-color: #ffde00; /* ソフトバンク光・イエロー */
  --accent-color: #f7f9fc;
  --text-main: #1d1d1f;
  --text-light: #6e6e73;
  --white: #ffffff;
  --platinum: #e5e5e5;
  --success: #34c759;
  --shadow: 0 10px 40px rgba(0,0,0,0.06);
  --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'SF Pro Display', 'Inter', 'Noto Sans JP', sans-serif;
  color: var(--text-main);
  line-height: 1.6;
  background-color: var(--white);
  -webkit-font-smoothing: antialiased;
}

/* 法令順守: PRバッジ 2023ステマ規制対応 */
.legal-tag {
  background: #fdf2f2;
  color: #c53030;
  font-size: 13px;
  font-weight: 700;
  text-align: center;
  padding: 12px;
  border-bottom: 2px solid #feb2b2;
  position: relative;
  z-index: 2000;
}

/* Header */
header {
  height: 80px;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 6%;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0,0,0,0.02);
}

.logo {
  font-size: 24px;
  font-weight: 900;
  color: var(--primary-color);
  text-decoration: none;
  letter-spacing: -0.5px;
}

.logo span {
  color: var(--secondary-color);
  background: #333;
  padding: 2px 8px;
  border-radius: 4px;
  margin-left: 5px;
}

.nav {
  display: flex;
  gap: 30px;
}

.nav a {
  text-decoration: none;
  color: var(--text-main);
  font-weight: 600;
  font-size: 15px;
  transition: var(--transition);
}

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

/* Hero Section */
.hero {
  padding: 100px 6%;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  align-items: center;
  gap: 60px;
  background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  overflow: hidden;
}

.hero-sub {
  display: inline-block;
  color: var(--primary-color);
  font-weight: 800;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 2px;
  margin-bottom: 20px;
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 4.2rem);
  line-height: 1.1;
  font-weight: 900;
  margin-bottom: 25px;
  color: #000;
}

.hero-title span {
  background: linear-gradient(to right, var(--primary-color), #007aff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-p {
  font-size: 1.25rem;
  color: var(--text-light);
  margin-bottom: 40px;
  max-width: 600px;
}

.cta-box {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 20px 45px;
  border-radius: 14px;
  text-decoration: none;
  font-weight: 800;
  font-size: 18px;
  transition: var(--transition);
  cursor: pointer;
}

.btn-main {
  background: var(--primary-color);
  color: var(--white);
  box-shadow: 0 10px 25px rgba(0, 78, 161, 0.3);
}

.btn-main:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px rgba(0, 78, 161, 0.4);
}

.cashback-badge {
  background: var(--secondary-color);
  color: #000;
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 900;
  font-size: 14px;
  width: fit-content;
}

.hero-img-wrap {
  position: relative;
}

.hero-img-wrap img {
  width: 100%;
  border-radius: 30px;
  box-shadow: 0 30px 60px rgba(0,0,0,0.12);
}

/* Feature Grid */
.section {
  padding: 120px 6%;
}

.section-title {
  text-align: center;
  font-size: 2.8rem;
  font-weight: 900;
  margin-bottom: 80px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 40px;
}

.feature-card {
  padding: 50px 40px;
  background: var(--accent-color);
  border-radius: 24px;
  transition: var(--transition);
  border: 1px solid transparent;
}

.feature-card:hover {
  background: var(--white);
  border-color: var(--primary-color);
  box-shadow: var(--shadow);
  transform: translateY(-10px);
}

.icon {
  font-size: 3rem;
  margin-bottom: 25px;
  display: block;
}

/* Banner Section */
.banner-promo {
  padding: 80px 6%;
  background: var(--primary-color);
  color: var(--white);
  border-radius: 40px;
  margin: 0 6% 120px;
  display: flex;
  align-items: center;
  gap: 60px;
}

.banner-content {
  flex: 1;
}

.banner-content h2 {
  font-size: 2.5rem;
  font-weight: 900;
  margin-bottom: 20px;
}

/* FAQ */
.faq-box {
  max-width: 900px;
  margin: 0 auto;
}

.faq-item {
  margin-bottom: 20px;
  padding: 30px;
  background: var(--accent-color);
  border-radius: 16px;
}

.faq-q {
  font-weight: 800;
  font-size: 1.2rem;
  margin-bottom: 10px;
  color: var(--primary-color);
}

/* Footer */
footer {
  background: #000;
  color: var(--white);
  padding: 100px 6% 50px;
}

.footer-nav {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 60px;
  margin-bottom: 80px;
}

.footer-logo {
  font-size: 26px;
  font-weight: 900;
  margin-bottom: 20px;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 15px;
}

.footer-links a {
  color: #888;
  text-decoration: none;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--white);
}

.bottom-bar {
  border-top: 1px solid #333;
  padding-top: 50px;
  text-align: center;
  font-size: 13px;
  color: #666;
}

/* Tablet / Mobile */
@media (max-width: 992px) {
  .hero {
    grid-template-columns: 1fr;
    text-align: center;
    padding-top: 60px;
  }
  .hero-p { margin: 0 auto 40px; }
  .cta-box { align-items: center; }
  .banner-promo {
    flex-direction: column;
    text-align: center;
  }
}