:root {
  --bg-color: #000000;
  --bg-secondary: #121212;
  --text-color: #ffffff;
  --accent-color: #333333;
  --highlight-color: #0099ff;
  --font-base: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-color);
  color: var(--text-color);
  font-family: var(--font-base);
  line-height: 1.8;
  letter-spacing: 0.05em;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

ul {
  list-style: none;
}



/* header */
/* header */
/* header */
header {
  background-color: rgba(0, 0, 0, 0.85);
  border-bottom: 1px solid var(--accent-color);
  padding: 0 20px;
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  height: 70px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 100%;
}

header>* {
  width: auto;
}

.pj-title {
  text-decoration: none;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.pj-title h1 {
  font-size: 1.2rem;
  text-align: left;
  font-weight: 800;
  letter-spacing: 0.05em;
  margin: 0;
  line-height: 1;
}

.pj-title h1 span {
  font-size: 0.5em;
  font-weight: normal;
  color: #888;
  margin-left: 10px;
}

header>p {
  display: none;
}

nav {
  border-top: none;
}

nav ul {
  display: flex;
  gap: 20px;
  margin: 0;
  padding: 0;
}

nav li {
  flex: initial;
  min-width: auto;
}

nav a {
  display: block;
  padding: 10px 15px;
  font-size: 0.8rem;
  font-weight: bold;
  color: #aaa;
  border-radius: 4px;
  transition: all 0.3s ease;
}

nav a:hover {
  color: #fff;
  background-color: rgba(255, 255, 255, 0.1);
}


/* main */
/* main */
/* main */
.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 80px 20px;
  border-bottom: 1px solid var(--accent-color);
}

h2 {
  font-size: 2.5rem;
  margin-bottom: 40px;
  font-weight: 200;
  letter-spacing: 0.2em;
  border-left: 4px solid #fff;
  padding-left: 20px;
  line-height: 1;
}

h3 {
  font-size: 1.5rem;
  margin: 40px 0 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--accent-color);
}


/* theme */
/* theme */
/* theme */
#theme li{
  list-style-type: square;
}


/* target */
/* target */
/* target */
#target dl {
  display: grid;
  grid-template-columns:　1fr;
  gap: 20px;
  align-items: start;
}

#target dt {
  font-weight: bold;
  font-size: 1.1rem;
  color: #aaa;
  border-top: 1px solid #333;
  padding-top: 10px;
  margin-top: 10px;
}

#target dd {
  margin-bottom: 10px;
  padding-left: 20px;
  border-left: 1px solid #333;
}

#target dd:first-of-type {
  margin-top: 20px;
}




/* persona */
/* persona */
/* persona */
#persona img{
  width: 100%;
  height: auto;
  object-fit: cover;
  border-color: white;
  border-radius: 10px;
  transform: scale(0.65);
  transition: 0.2s ease;
}

#persona img:hover {
  border-color: #555;
  transform: scale(0.7);
}

/* system */
/* system */
/* system */
.system-lead {
  background-color: var(--bg-secondary);
  padding: 30px;
  margin-bottom: 50px;
  border-left: 2px solid #fff;
}

.system-lead p strong {
  color: #fff;
  border-bottom: 1px solid #fff;
}

.lead-img{
  width: 100%;
  height: auto;
  margin-top: 2rem;
  object-fit: cover;
  border-radius: 10px;
  transform: scale(0.8);
}

.system-block {
  margin-bottom: 60px;
  overflow: hidden;
}

.system-block h4 {
  font-size: 1.2rem;
  margin-bottom: 15px;
  color: #fff;
  border-bottom: 2px solid #fff;
  display: inline-block;
  padding-bottom: 5px;
}

.section-desc {
  margin-bottom: 20px;
  color: #888;
  font-size: 0.95rem;
}

.feature-item {
  background-color: #0a0a0a;
  border: 1px solid #222;
  padding: 25px;
  margin-bottom: 25px;
  transition: transform 0.3s, border-color 0.3s;
}

.feature-item:hover {
  border-color: #555;
  transform: translateY(-2px);
}

.demo-img{
  width: 100%;
  height: auto;
  object-fit: cover;
}

/* DL Layout for System Section */
.system-block dl dt {
  float: left;
  clear: left;
  width: 100%;
  font-weight: bold;
  margin-top: 20px;
  color: #ddd;
}

.system-block dl dd {
  float: left;
  width: 100%;
  margin-left: 0;
  padding-left: 15px;
  border-left: 1px solid #444;
  margin-bottom: 10px;
  color: #999;
}



/* conclusion */
/* conclusion */
/* conclusion */
#conclusion {
  text-align: center;
  border-bottom: none;
  padding-bottom: 120px;
}

#conclusion h3 {
  border: none;
  font-size: 1.8rem;
  margin-bottom: 30px;
}

#conclusion p {
  max-width: 600px;
  margin: 0 auto 20px;
  color: #ccc;
}

.conclusion-message {
  margin-top: 40px !important;
  font-weight: bold;
  color: #fff !important;
  font-size: 1.1rem;
}

.phone-mockup {
  width: 375px;
  /* スマホの横幅 */
  height: 650px;
  /* スマホの縦幅 */
  background: #000;
  border-radius: 40px;
  padding: 12px;
  /* ベゼル（枠）の太さ */
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3);
  position: relative;
  margin: 0 auto;
  border: 4px solid #333;
}

/* ノッチ（カメラ部分） */
.phone-mockup::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 150px;
  height: 25px;
  background: #000;
  border-bottom-left-radius: 16px;
  border-bottom-right-radius: 16px;
  z-index: 10;
}

/* iframe（埋め込み画面） */
.phone-screen {
  width: 100%;
  height: 100%;
  border: none;
  border-radius: 30px;
  background: #fff;
  overflow: hidden;
}

/* footer */
/* footer */
/* footer */
footer {
  background-color: var(--bg-secondary);
  padding: 40px;
  text-align: center;
  font-size: 0.8rem;
  color: #555;
}




/* responsive */
/* responsive */
/* responsive */
@media (max-width: 768px) {
  header {
    height: auto;
    /* 高さを自動に戻す */
    flex-direction: column;
    /* 縦積みに戻す */
    padding: 15px 0;
    gap: 10px;
  }

  .pj-title h1 span {
    display: block;
    margin-left: 0;
    margin-top: 5px;
    text-align: center;
  }

  nav ul {
    gap: 5px;
    flex-wrap: wrap;
    justify-content: center;
  }

  nav a {
    padding: 5px 10px;
    font-size: 0.75rem;
  }

  .pj-title h1 {
    font-size: 1.2rem;
  }

  h2 {
    font-size: 2rem;
  }

  #target dl {
    grid-template-columns: 1fr;
    gap: 5px;
  }

  #target dt {
    border-top: none;
    border-left: 3px solid #333;
    padding-left: 10px;
    margin-bottom: 5px;
  }

  #target dd {
    border-left: none;
    padding-left: 13px;
    margin-bottom: 20px;
  }

  #persona th,
  #persona td {
    display: block;
    width: 100%;
  }

  #persona th {
    margin-top: 20px;
  }
}