/* kojen-5 — 科見 × 程式忍者 AI 情境實戰美語 設計系統 */
:root {
  --ink: #0e1430;
  --ink-2: #1c2550;
  --indigo: #3a46e0;
  --indigo-2: #6b73ff;
  --violet: #8b5cf6;
  --coral: #ff6b5c;
  --amber: #ffb020;
  --mint: #19c37d;
  --paper: #ffffff;
  --cloud: #f5f6fc;
  --cloud-2: #eceefb;
  --line: #e2e5f3;
  --muted: #5b6186;
  --text: #1a1f3d;
  --radius: 18px;
  --radius-lg: 28px;
  --shadow-sm: 0 2px 10px rgba(20, 25, 60, .06);
  --shadow: 0 14px 40px rgba(30, 36, 100, .12);
  --shadow-lg: 0 30px 80px rgba(30, 36, 100, .22);
  --maxw: 1140px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang TC",
    "Noto Sans TC", "Microsoft JhengHei", Roboto, Helvetica, Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--paper);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
h1, h2, h3 { line-height: 1.2; margin: 0 0 .4em; letter-spacing: -.01em; }
p { margin: 0 0 1em; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }
.center { text-align: center; }
.muted { color: var(--muted); }

/* ---------- 導覽列 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav__in {
  max-width: var(--maxw); margin: 0 auto; padding: 12px 22px;
  display: flex; align-items: center; gap: 20px;
}
.brand { display: flex; align-items: center; gap: 11px; font-weight: 800; font-size: 18px; }
.brand__mark {
  width: 38px; height: 38px; border-radius: 11px;
  display: grid; place-items: center; font-size: 20px;
  background: linear-gradient(135deg, var(--indigo), var(--violet));
  color: #fff; box-shadow: var(--shadow-sm);
}
.brand small { display: block; font-size: 11px; font-weight: 600; color: var(--muted); letter-spacing: .08em; }
.nav__links { margin-left: auto; display: flex; gap: 26px; align-items: center; }
.nav__links a { font-weight: 600; font-size: 15px; color: var(--ink-2); }
.nav__links a:hover { color: var(--indigo); }
.nav__links .btn { color: #fff; }
.nav__links .btn--ghost { color: var(--indigo); }
@media (max-width: 820px) { .nav__links a:not(.btn) { display: none; } }

/* ---------- 按鈕 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 13px 24px; border-radius: 999px; border: 0; cursor: pointer;
  font: inherit; font-weight: 700; font-size: 15px;
  background: linear-gradient(135deg, var(--indigo), var(--violet));
  color: #fff; box-shadow: 0 10px 26px rgba(58, 70, 224, .34);
  transition: transform .15s ease, box-shadow .15s ease, opacity .15s;
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 16px 34px rgba(58, 70, 224, .42); }
.btn:active { transform: translateY(0); }
.btn--ghost {
  background: #fff; color: var(--indigo); border: 1.5px solid var(--line);
  box-shadow: var(--shadow-sm);
}
.btn--ghost:hover { border-color: var(--indigo-2); box-shadow: var(--shadow); }
.btn--coral { background: linear-gradient(135deg, var(--coral), var(--amber)); box-shadow: 0 10px 26px rgba(255, 107, 92, .34); }
.btn--lg { padding: 16px 32px; font-size: 16px; }
.btn--block { width: 100%; justify-content: center; }
.btn[disabled] { opacity: .5; cursor: not-allowed; transform: none; }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden;
  background:
    radial-gradient(900px 500px at 85% -10%, rgba(139, 92, 246, .22), transparent 60%),
    radial-gradient(700px 500px at 5% 10%, rgba(255, 107, 92, .16), transparent 55%),
    linear-gradient(180deg, #0e1430 0%, #141b43 55%, #1a2150 100%);
  color: #fff;
}
.hero__in { max-width: var(--maxw); margin: 0 auto; padding: 78px 22px 96px;
  display: grid; grid-template-columns: 1.08fr .92fr; gap: 54px; align-items: center; }
@media (max-width: 900px) { .hero__in { grid-template-columns: 1fr; gap: 36px; padding: 54px 22px 70px; } }
.pill {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 7px 15px; border-radius: 999px; font-size: 13px; font-weight: 700;
  background: rgba(255, 255, 255, .12); border: 1px solid rgba(255, 255, 255, .22);
  backdrop-filter: blur(6px); margin-bottom: 22px;
}
.hero h1 { font-size: clamp(34px, 5vw, 56px); font-weight: 900; margin-bottom: 18px; }
.hero h1 .grad {
  background: linear-gradient(120deg, var(--amber), var(--coral) 55%, var(--indigo-2));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.hero__lead { font-size: clamp(16px, 2.3vw, 20px); color: #c9cdf0; max-width: 540px; }
.hero__cta { display: flex; gap: 14px; flex-wrap: wrap; margin-top: 30px; }
.hero__stats { display: flex; gap: 30px; margin-top: 40px; flex-wrap: wrap; }
.hero__stats b { display: block; font-size: 30px; font-weight: 900; }
.hero__stats span { font-size: 13px; color: #a6abdb; }

/* Hero 右側對話示意卡 */
.chat {
  background: rgba(255, 255, 255, .06); border: 1px solid rgba(255, 255, 255, .14);
  border-radius: var(--radius-lg); padding: 22px; box-shadow: var(--shadow-lg);
  backdrop-filter: blur(8px);
}
.chat__head { display: flex; align-items: center; gap: 10px; margin-bottom: 16px; font-weight: 700; }
.chat__dot { width: 10px; height: 10px; border-radius: 50%; background: var(--mint); box-shadow: 0 0 0 4px rgba(25,195,125,.2); }
.bubble { padding: 12px 15px; border-radius: 15px; margin-bottom: 11px; font-size: 15px; max-width: 86%; }
.bubble--sys { background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.14); }
.bubble--zh { background: rgba(255, 176, 32, .18); border: 1px solid rgba(255,176,32,.4); margin-left: auto; }
.bubble--coach { background: rgba(107, 115, 255, .22); border: 1px solid rgba(107,115,255,.5); }
.bubble--en { background: var(--mint); color: #042818; margin-left: auto; font-weight: 700; }
.bubble small { display:block; opacity:.75; font-size:11px; margin-bottom:3px; font-weight:700; letter-spacing:.05em; }

/* ---------- 區塊通用 ---------- */
section { padding: 84px 0; }
.sec-tag { color: var(--indigo); font-weight: 800; letter-spacing: .12em; font-size: 13px; text-transform: uppercase; }
.sec-title { font-size: clamp(26px, 3.6vw, 40px); font-weight: 900; margin: 8px 0 14px; }
.sec-lead { color: var(--muted); max-width: 640px; margin: 0 auto; font-size: 17px; }
.bg-cloud { background: var(--cloud); }

/* 方法循環 */
.loop { display: grid; grid-template-columns: repeat(5, 1fr); gap: 14px; margin-top: 48px; }
@media (max-width: 860px) { .loop { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .loop { grid-template-columns: 1fr; } }
.loop__step {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 18px; text-align: center; box-shadow: var(--shadow-sm); position: relative;
}
.loop__n {
  width: 40px; height: 40px; border-radius: 12px; margin: 0 auto 14px;
  display: grid; place-items: center; font-weight: 900; font-size: 18px; color: #fff;
  background: linear-gradient(135deg, var(--indigo), var(--violet));
}
.loop__step h3 { font-size: 17px; }
.loop__step p { font-size: 14px; color: var(--muted); margin: 0; }

/* 卡片格 */
.grid { display: grid; gap: 22px; }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 900px) { .grid--3 { grid-template-columns: 1fr 1fr; } }
@media (max-width: 640px) { .grid--3, .grid--2 { grid-template-columns: 1fr; } }

.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px; box-shadow: var(--shadow-sm); transition: transform .18s, box-shadow .18s;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.card__ico { font-size: 34px; margin-bottom: 12px; }
.card h3 { font-size: 20px; }
.card p { color: var(--muted); margin: 0; font-size: 15px; }

/* 情境卡 */
.scn { display: grid; gap: 20px; }
.scn-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm); transition: transform .18s, box-shadow .18s;
  display: flex; flex-direction: column;
}
.scn-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.scn-card__top {
  padding: 26px; background: linear-gradient(135deg, var(--cloud-2), #fff);
  display: flex; align-items: center; gap: 14px;
}
.scn-card__emoji {
  width: 58px; height: 58px; border-radius: 16px; display: grid; place-items: center;
  font-size: 30px; background: #fff; box-shadow: var(--shadow-sm);
}
.scn-card__body { padding: 0 26px 24px; flex: 1; display: flex; flex-direction: column; }
.scn-card__body p { color: var(--muted); font-size: 14px; flex: 1; }
.tag {
  display: inline-block; padding: 4px 11px; border-radius: 999px; font-size: 12px; font-weight: 700;
  background: var(--cloud-2); color: var(--ink-2); margin: 0 6px 6px 0;
}
.tag--mode { background: rgba(25,195,125,.14); color: #0b7a4d; }

/* 課程方案 / 價格 */
.tracks { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; align-items: stretch; }
@media (max-width: 900px) { .tracks { grid-template-columns: 1fr; max-width: 460px; margin: 0 auto; } }
.track {
  background: #fff; border: 1.5px solid var(--line); border-radius: var(--radius-lg);
  padding: 30px; display: flex; flex-direction: column; position: relative;
}
.track--hot { border-color: var(--indigo-2); box-shadow: var(--shadow); }
.track__flag {
  position: absolute; top: -13px; left: 50%; transform: translateX(-50%);
  background: linear-gradient(135deg, var(--coral), var(--amber)); color: #fff;
  padding: 5px 16px; border-radius: 999px; font-size: 12px; font-weight: 800; letter-spacing: .05em;
}
.track h3 { font-size: 22px; }
.track__age { color: var(--indigo); font-weight: 700; font-size: 14px; margin-bottom: 14px; }
.track__price { font-size: 34px; font-weight: 900; margin: 8px 0; }
.track__price span { font-size: 15px; font-weight: 600; color: var(--muted); }
.track ul { list-style: none; padding: 0; margin: 18px 0 24px; flex: 1; }
.track li { padding: 8px 0 8px 28px; position: relative; font-size: 15px; border-top: 1px solid var(--cloud-2); }
.track li:first-child { border-top: 0; }
.track li::before { content: "✓"; position: absolute; left: 0; color: var(--mint); font-weight: 900; }

/* 合作雙方 */
.combo { display: grid; grid-template-columns: 1fr auto 1fr; gap: 24px; align-items: center; }
@media (max-width: 760px) { .combo { grid-template-columns: 1fr; } .combo__x { display:none; } }
.combo__card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg); padding: 30px; box-shadow: var(--shadow-sm); }
.combo__card h3 { font-size: 22px; }
.combo__x { font-size: 40px; font-weight: 900; color: var(--indigo-2); }

/* FAQ */
.faq { max-width: 760px; margin: 40px auto 0; }
.faq details {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 4px 22px; margin-bottom: 12px; box-shadow: var(--shadow-sm);
}
.faq summary { cursor: pointer; font-weight: 700; padding: 16px 0; list-style: none; display: flex; justify-content: space-between; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--indigo); font-size: 22px; }
.faq details[open] summary::after { content: "−"; }
.faq p { color: var(--muted); padding-bottom: 16px; margin: 0; }

/* 表單 */
.form-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 34px; box-shadow: var(--shadow); max-width: 620px; margin: 40px auto 0;
}
.field { margin-bottom: 16px; }
.field label { display: block; font-weight: 700; font-size: 14px; margin-bottom: 6px; }
.field input, .field select, .field textarea {
  width: 100%; padding: 13px 15px; border: 1.5px solid var(--line); border-radius: 12px;
  font: inherit; font-size: 15px; background: var(--cloud); transition: border .15s, background .15s;
}
.field input:focus, .field select:focus, .field textarea:focus {
  outline: 0; border-color: var(--indigo-2); background: #fff;
}
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
@media (max-width: 520px) { .row2 { grid-template-columns: 1fr; } }
.form-msg { margin-top: 14px; padding: 13px 16px; border-radius: 12px; font-weight: 600; display: none; }
.form-msg.ok { display: block; background: rgba(25,195,125,.12); color: #0b7a4d; }
.form-msg.err { display: block; background: rgba(255,107,92,.12); color: #c0392b; }

/* CTA 帶狀 */
.cta-band {
  background: linear-gradient(135deg, var(--indigo), var(--violet));
  color: #fff; border-radius: var(--radius-lg); padding: 54px; text-align: center;
  box-shadow: var(--shadow-lg);
}
.cta-band h2 { font-size: clamp(24px, 3.4vw, 36px); font-weight: 900; }
.cta-band p { color: #dfe2ff; max-width: 560px; margin: 0 auto 26px; }

/* Footer */
.footer { background: var(--ink); color: #aab0dd; padding: 48px 0 30px; }
.footer__in { display: flex; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.footer a { color: #cfd3f5; }
.footer a:hover { color: #fff; }
.footer__bottom { border-top: 1px solid rgba(255,255,255,.1); margin-top: 28px; padding-top: 20px; font-size: 13px; }

/* 動效 */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; } }