*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'Hiragino Sans', 'Noto Sans JP', 'Segoe UI', sans-serif; background: #ffffff; color: #1a1a1a; line-height: 1.75; }
a { text-decoration: none; color: inherit; }
:root {
  --orange: #f97316;
  --orange-light: #fff7ed;
  --orange-mid: #fed7aa;
  --red: #ef4444;
  --coral: #fb923c;
  --bg: #ffffff;
  --bg2: #fafafa;
  --gray: #6b7280;
  --dark: #111827;
  --border: #e5e7eb;
  --radius: 16px;
  --tr: 0.25s ease;
}
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: #fff; }
::-webkit-scrollbar-thumb { background: var(--orange); border-radius: 3px; }

/* NAV */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  height: 60px; background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 6%;
}
.nav-logo {
  font-weight: 900; font-size: 1.1rem;
  background: linear-gradient(135deg, var(--orange), var(--red));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.nav-links { display: flex; gap: 1.8rem; align-items: center; }
.nav-links a { font-size: 0.83rem; color: var(--gray); font-weight: 500; transition: color var(--tr); }
.nav-links a:hover { color: var(--orange); }
.nav-ham { display: none; flex-direction: column; gap: 5px; cursor: pointer; }
.nav-ham span { width: 22px; height: 2px; background: var(--dark); border-radius: 2px; }

/* HERO */
#hero {
  min-height: 100vh; padding: 80px 6% 60px;
  display: flex; align-items: center;
  background: linear-gradient(160deg, #fff7ed 0%, #ffffff 60%, #fff1f2 100%);
  position: relative; overflow: hidden;
}
#hero::before {
  content: ''; position: absolute;
  width: 600px; height: 600px; border-radius: 50%;
  background: radial-gradient(circle, rgba(249,115,22,0.1) 0%, transparent 70%);
  top: -100px; right: -100px; pointer-events: none;
}
.hero-inner { max-width: 1060px; margin: 0 auto; width: 100%; display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.hero-number { font-size: 0.75rem; font-weight: 700; letter-spacing: 3px; text-transform: uppercase; color: var(--orange); margin-bottom: 1rem; }
.hero-name { font-size: clamp(2.8rem, 5vw, 4rem); font-weight: 900; color: var(--dark); line-height: 1.05; margin-bottom: 0.5rem; }
.hero-name span { background: linear-gradient(135deg, var(--orange), var(--red)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero-role { font-size: 1.05rem; font-weight: 700; color: var(--orange); margin-bottom: 1.2rem; }
.hero-catch {
  font-size: 1.1rem; font-weight: 700; color: var(--dark);
  border-left: 4px solid var(--orange);
  padding: 0.6rem 0 0.6rem 1rem;
  margin-bottom: 1.5rem;
  background: var(--orange-light); border-radius: 0 8px 8px 0;
}
.hero-desc { font-size: 0.92rem; color: var(--gray); max-width: 420px; margin-bottom: 2rem; }
.hero-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 2.5rem; }
.hero-chip {
  background: var(--bg2); border: 1.5px solid var(--border);
  border-radius: 6px; padding: 5px 14px;
  font-size: 0.78rem; font-weight: 600; color: var(--dark);
  transition: var(--tr);
}
.hero-chip:hover { border-color: var(--orange); color: var(--orange); }

/* PROFILE PANEL */
.profile-panel {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: 20px; overflow: hidden;
  box-shadow: 0 12px 48px rgba(0,0,0,0.06);
}
.pp-header {
  background: linear-gradient(135deg, var(--orange), var(--red));
  padding: 2rem; text-align: center;
}
.pp-avatar { font-size: 3.5rem; margin-bottom: 0.8rem; }
.pp-name { font-size: 1.3rem; font-weight: 900; color: #fff; }
.pp-univ { font-size: 0.82rem; color: rgba(255,255,255,0.8); margin-top: 0.3rem; }
.pp-body { padding: 1.5rem 2rem; }
.pp-row { display: flex; align-items: center; gap: 10px; padding: 9px 0; border-bottom: 1px solid var(--border); font-size: 0.83rem; }
.pp-row:last-child { border-bottom: none; }
.pp-icon { width: 26px; text-align: center; }
.pp-lbl { color: var(--gray); width: 76px; flex-shrink: 0; }
.pp-val { font-weight: 700; color: var(--dark); }

/* SECTIONS */
section { padding: 90px 6%; }
.container { max-width: 1060px; margin: 0 auto; }
.sec-header { margin-bottom: 3rem; text-align: center; }
.sec-num { font-size: 3rem; font-weight: 900; color: var(--orange-mid); line-height: 1; margin-bottom: 0.2rem; }
.sec-en { font-size: 0.72rem; font-weight: 700; letter-spacing: 3px; text-transform: uppercase; color: var(--orange); }
.sec-ja { font-size: clamp(1.6rem, 2.5vw, 2.1rem); font-weight: 900; color: var(--dark); margin-top: 0.3rem; }
.sec-divider { width: 48px; height: 4px; background: linear-gradient(90deg, var(--orange), var(--red)); border-radius: 2px; margin: 0.8rem auto 0; }

/* SELF PR */
#selfpr { background: var(--bg); }
.pr-box {
  background: var(--orange-light); border: 1px solid var(--orange-mid);
  border-radius: var(--radius); padding: 2.5rem; margin-bottom: 2rem;
  position: relative;
}
.pr-box::before { content: '"'; font-size: 6rem; color: var(--orange-mid); position: absolute; top: -1rem; left: 1.5rem; line-height: 1; font-family: serif; }
.pr-box-text { font-size: 0.97rem; color: #374151; line-height: 1.9; padding-top: 1rem; }
.pr-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
.pr-c {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.5rem;
  transition: var(--tr); position: relative; overflow: hidden;
}
.pr-c::after { content: ''; position: absolute; bottom: 0; left: 0; right: 0; height: 3px; background: linear-gradient(90deg, var(--orange), var(--red)); opacity: 0; transition: var(--tr); }
.pr-c:hover::after { opacity: 1; }
.pr-c:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(0,0,0,0.07); }
.pr-c-icon { font-size: 2rem; margin-bottom: 0.8rem; }
.pr-c-title { font-size: 0.95rem; font-weight: 800; color: var(--dark); margin-bottom: 0.5rem; }
.pr-c-body { font-size: 0.82rem; color: var(--gray); }

/* EDUCATION */
#education { background: var(--bg2); }
.edu-cards { display: flex; flex-direction: column; gap: 1rem; max-width: 720px; margin: 0 auto; }
.edu-card {
  display: grid; grid-template-columns: auto 1fr;
  gap: 0; overflow: hidden;
  border-radius: var(--radius); border: 1px solid var(--border);
  transition: var(--tr);
}
.edu-card:hover { border-color: var(--orange); box-shadow: 0 4px 16px rgba(249,115,22,0.1); }
.edu-card-accent { width: 6px; background: linear-gradient(to bottom, var(--orange), var(--red)); }
.edu-card-body { padding: 1.4rem 1.8rem; background: var(--bg); }
.edu-yr { font-size: 0.76rem; font-weight: 700; color: var(--orange); margin-bottom: 0.3rem; }
.edu-school { font-size: 1rem; font-weight: 800; color: var(--dark); }
.edu-dept { font-size: 0.84rem; color: var(--gray); }
.edu-note { font-size: 0.8rem; color: var(--orange); font-weight: 700; margin-top: 0.4rem; }

/* RESEARCH */
#research { background: var(--bg); }
.research-wrap { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.r-card {
  background: #fffaf5; border: 1px solid var(--border);
  border-radius: var(--radius); padding: 2rem;
  transition: var(--tr);
}
.r-card:hover { border-color: var(--orange); }
.r-label { font-size: 0.72rem; font-weight: 700; color: var(--orange); letter-spacing: 1px; margin-bottom: 0.4rem; }
.r-title { font-size: 1rem; font-weight: 800; color: var(--dark); margin-bottom: 0.8rem; }
.r-body { font-size: 0.86rem; color: var(--gray); margin-bottom: 1.2rem; }
.r-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.r-tag { background: var(--orange-light); border: 1px solid var(--orange-mid); color: var(--orange); border-radius: 4px; padding: 2px 10px; font-size: 0.74rem; font-weight: 700; }

/* INTERNSHIP */
#internship { background: var(--bg2); }
.i-list { display: flex; flex-direction: column; gap: 1rem; }
.i-card {
  background: var(--bg); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.8rem 2rem;
  transition: var(--tr); position: relative;
}
.i-card:hover { border-color: var(--orange); box-shadow: 0 4px 20px rgba(249,115,22,0.08); }
.i-top { display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem; margin-bottom: 0.6rem; flex-wrap: wrap; }
.i-title { font-size: 1rem; font-weight: 800; color: var(--dark); }
.i-badge { background: linear-gradient(135deg, var(--orange), var(--red)); color: #fff; border-radius: 4px; padding: 3px 10px; font-size: 0.72rem; font-weight: 700; white-space: nowrap; }
.i-meta { display: flex; gap: 1rem; font-size: 0.8rem; color: var(--gray); margin-bottom: 0.8rem; flex-wrap: wrap; }
.i-meta span { display: flex; align-items: center; gap: 4px; }
.i-desc { font-size: 0.88rem; color: #374151; margin-bottom: 0.8rem; }
.i-tags { display: flex; flex-wrap: wrap; gap: 6px; }
.i-tag { background: var(--orange-light); color: var(--orange); border-radius: 4px; padding: 2px 9px; font-size: 0.74rem; font-weight: 600; }

/* ACTIVITIES */
#activities { background: var(--bg); }
.act-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 1.2rem; }
.act-card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.6rem;
  transition: var(--tr); position: relative; overflow: hidden;
}
.act-card:hover { border-color: var(--orange); }
.act-card:hover .act-bg-num { opacity: 1; }
.act-bg-num { position: absolute; right: 1rem; bottom: 0.5rem; font-size: 4rem; font-weight: 900; color: var(--orange-mid); opacity: 0.5; transition: var(--tr); line-height: 1; }
.act-icon { font-size: 1.8rem; margin-bottom: 0.8rem; }
.act-title { font-size: 0.93rem; font-weight: 800; color: var(--dark); margin-bottom: 0.5rem; }
.act-desc { font-size: 0.81rem; color: var(--gray); }

/* SKILLS */
#skills { background: var(--bg2); }
.sk-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 1.5rem; }
.sk-box { background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.8rem; }
.sk-head { display: flex; align-items: center; gap: 8px; font-size: 0.9rem; font-weight: 800; color: var(--dark); margin-bottom: 1.2rem; padding-bottom: 0.6rem; border-bottom: 2px solid var(--orange-mid); }
.sk-row { margin-bottom: 1rem; }
.sk-top { display: flex; justify-content: space-between; font-size: 0.82rem; margin-bottom: 5px; }
.sk-pct { color: var(--orange); font-weight: 700; }
.sk-bar { height: 5px; background: var(--border); border-radius: 3px; overflow: hidden; }
.sk-fill { height: 100%; background: linear-gradient(90deg, var(--orange), var(--red)); border-radius: 3px; width: 0; transition: width 1.2s ease; }
.sk-tools { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 1rem; }
.sk-tool { background: var(--orange-light); border: 1px solid var(--orange-mid); color: var(--orange); border-radius: 4px; padding: 3px 10px; font-size: 0.74rem; font-weight: 600; }

/* CERTIFICATIONS */
#certifications { background: var(--bg); }
.cert-wrap { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 1rem; }
.cert-card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1.5rem;
  transition: var(--tr); text-align: center;
}
.cert-card:hover { border-color: var(--orange); transform: translateY(-3px); box-shadow: 0 8px 24px rgba(249,115,22,0.1); }
.cert-ico { font-size: 2.2rem; margin-bottom: 0.7rem; }
.cert-nm { font-size: 0.88rem; font-weight: 700; color: var(--dark); margin-bottom: 0.3rem; }
.cert-by { font-size: 0.74rem; color: var(--gray); margin-bottom: 0.6rem; }
.cert-yr { display: inline-block; background: linear-gradient(135deg, var(--orange), var(--red)); color: #fff; border-radius: 4px; padding: 2px 10px; font-size: 0.72rem; font-weight: 700; }

/* FOOTER */
footer {
  background: var(--dark); color: #9ca3af; padding: 3rem 6%; text-align: center;
}
.ft-nm { font-size: 1.2rem; font-weight: 900; margin-bottom: 0.4rem;
  background: linear-gradient(135deg, var(--orange), var(--red));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.ft-cp { font-size: 0.78rem; color: #4b5563; margin-top: 1.5rem; }

/* SCROLL TOP */
.stb { position: fixed; bottom: 28px; right: 28px; width: 44px; height: 44px; border-radius: 8px; background: linear-gradient(135deg, var(--orange), var(--red)); color: #fff; display: flex; align-items: center; justify-content: center; font-size: 1rem; cursor: pointer; opacity: 0; pointer-events: none; box-shadow: 0 4px 16px rgba(249,115,22,0.35); transition: var(--tr); z-index: 90; }
.stb.on { opacity: 1; pointer-events: auto; }
.stb:hover { transform: translateY(-3px); }

.fi { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fi.on { opacity: 1; transform: none; }

@media (max-width: 860px) {
  .hero-inner, .research-wrap { grid-template-columns: 1fr; }
  .hero-inner { gap: 2.5rem; }
  .hero-chips { margin-bottom: 0; }
  .pr-cards { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .nav-ham { display: flex; }
  .act-card { display: grid; grid-template-columns: auto 1fr; grid-template-rows: auto auto; column-gap: 1rem; align-items: center; }
  .act-icon { grid-column: 1; grid-row: 1; margin-bottom: 0; }
  .act-title { grid-column: 2; grid-row: 1; }
  .act-desc { grid-column: 1 / -1; grid-row: 2; }
  .act-bg-num { display: none; }
  .pr-c { display: grid; grid-template-columns: auto 1fr; grid-template-rows: auto auto; column-gap: 1rem; align-items: center; }
  .pr-c-icon { grid-column: 1; grid-row: 1; margin-bottom: 0; }
  .pr-c-title { grid-column: 2; grid-row: 1; }
  .pr-c-body { grid-column: 1 / -1; grid-row: 2; }
}
.mob-nav { display: none; position: fixed; inset: 0; z-index: 99; background: rgba(255,255,255,0.98); flex-direction: column; align-items: center; justify-content: center; gap: 2rem; }
.mob-nav.open { display: flex; }
.mob-nav a { font-size: 1.4rem; font-weight: 700; color: var(--dark); }
.mob-close { position: absolute; top: 16px; right: 6%; font-size: 1.8rem; cursor: pointer; color: var(--gray); }