/* ========================================
   一筆跑 - APP 介紹頁樣式
   版型參考 bp.aipost.tw/intro（導覽列、Hero＋手機＋浮動卡、交錯區塊、步驟、FAQ、CTA），
   配色改用一筆跑 design tokens：橘＝行動、萊姆＝分數、琥珀＝點亮。
   ======================================== */

:root {
  --yb-primary: #ff6b2c;
  --yb-primary-dark: #e5561a;
  --yb-primary-light: #fff1ea;
  --yb-on-primary: #0b0e13; /* 橘底用黑字（同 App 的 on-accent），白字對比僅約 2.9:1 */
  --yb-primary-text: #b8420f; /* 淺底上的橘色小字，對比約 5:1 */
  --yb-primary-large: #e5561a; /* 大字標題用 */
  --yb-primary-alpha: rgba(255, 107, 44, 0.12);
  --yb-lime: #d4ff3a;
  --yb-amber: #ffb547;
  --yb-info: #3b82f6;
  --yb-friend: #7c5cf0;
  --yb-dark: #0b0e13;
  --yb-dark-card: #171c24;
  --yb-dark-border: #2e3745;
  --yb-text: #1e293b;
  --yb-text-second: #64748b;
  --yb-text-light: #64748b;
  --yb-bg: #f8fafc;
  --yb-card: #ffffff;
  --yb-border: #e2e8f0;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

body {
  font-family: "Noto Sans TC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--yb-text-second);
  background: var(--yb-card);
  overflow-x: hidden;
  line-height: 1.6;
}

.yb-container { width: 100%; max-width: 1120px; margin: 0 auto; padding: 0 20px; }

/* ---------- 公告列 ---------- */
.yb-announce-bar {
  border-bottom: 1px solid #1b222c;
  display: flex; align-items: center; justify-content: center; gap: 8px;
  padding: 8px 16px; background: var(--yb-dark); color: var(--yb-lime);
  font-size: 13px; font-weight: 600; text-align: center;
}
.yb-announce-bar b { color: #fff; }

/* ---------- 導覽列 ---------- */
.yb-navbar {
  position: sticky; top: 0; z-index: 50;
  background: rgba(11, 14, 19, 0.9);
  backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.yb-navbar .yb-container { display: flex; align-items: center; justify-content: space-between; min-height: 60px; }
.yb-logo { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 17px; color: #f4f6f9; }
.yb-logo img { width: 32px; height: 32px; border-radius: 8px; }
.yb-nav-links { display: flex; align-items: center; gap: 24px; }
.yb-nav-links a { font-size: 14px; font-weight: 500; color: #c3cbd6; transition: color 0.2s; }
.yb-nav-links a:hover { color: var(--yb-lime); }
.yb-nav-btn {
  background: var(--yb-primary); color: var(--yb-on-primary) !important; border-radius: 20px;
  font-weight: 600; padding: 8px 20px; transition: all 0.2s; white-space: nowrap;
}
.yb-nav-btn:hover { background: #ff8247; box-shadow: 0 4px 12px rgba(229, 86, 26, 0.4); }
.yb-burger { display: none; width: 44px; height: 44px; border: 0; background: transparent; cursor: pointer; border-radius: 12px; flex-direction: column; align-items: center; justify-content: center; gap: 5px; }
.yb-burger span { display: block; width: 22px; height: 2px; background: #f4f6f9; border-radius: 2px; transition: transform 0.2s, opacity 0.2s; }
.yb-burger[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.yb-burger[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.yb-burger[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
.yb-burger:focus-visible, .yb-nav-links a:focus-visible, .yb-btn:focus-visible { outline: 3px solid var(--yb-info); outline-offset: 2px; }
@media (max-width: 860px) {
  .yb-navbar .yb-container { position: relative; }
  .yb-burger { display: flex; }
  .yb-nav-links {
    display: none; position: absolute; top: 100%; left: 0; right: 0; flex-direction: column; align-items: stretch; gap: 0;
    background: #0f131a; border-bottom: 1px solid var(--yb-dark-border); box-shadow: 0 12px 24px rgba(0, 0, 0, 0.4); padding: 8px 20px 16px;
  }
  .yb-nav-links.open { display: flex; }
  .yb-nav-links a { padding: 14px 0; font-size: 16px; border-bottom: 1px solid var(--yb-dark-border); }
  .yb-nav-links a.yb-nav-btn { margin-top: 12px; text-align: center; border-bottom: 0; padding: 12px 20px; }
}

/* ---------- 動畫 ---------- */
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

/* ---------- 共用：徽章、簡介、圖示、按鈕 ---------- */
/* ---------- Hero ---------- */
.yb-badge {
  display: inline-flex; align-items: center; gap: 4px;
  background: var(--yb-primary-alpha); color: var(--yb-primary-text);
  border: 1px solid rgba(255, 107, 44, 0.3); border-radius: 20px;
  padding: 5px 14px; font-size: 13px; font-weight: 600; margin-bottom: 18px;
}
.yb-hero-definition {
  font-size: 14px; line-height: 1.7; background: var(--yb-primary-light);
  border-radius: 12px; padding: 14px 16px; margin-bottom: 28px;
}
.yb-hero-definition strong { color: var(--yb-primary-text); font-weight: 700; }
.yb-benefits { display: grid; grid-template-columns: 1fr 1fr; gap: 14px 20px; margin-bottom: 28px; }
.yb-benefits li { display: flex; align-items: center; gap: 12px; }
.yb-benefits strong { display: block; font-size: 15px; color: var(--yb-text); }
.yb-benefits span.t { font-size: 13px; line-height: 1.5; display: block; }
.yb-icon {
  width: 38px; height: 38px; flex-shrink: 0; border-radius: 10px; font-size: 19px;
  background: var(--yb-primary-alpha); display: flex; align-items: center; justify-content: center;
}
.yb-icon--lime { background: rgba(160, 200, 0, 0.16); }
.yb-icon--amber { background: rgba(255, 181, 71, 0.2); }
.yb-icon--purple { background: rgba(124, 92, 240, 0.12); }
.yb-icon--blue { background: rgba(59, 130, 246, 0.12); }

.yb-cta-row { display: flex; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.yb-btn {
  display: inline-flex; align-items: center; gap: 8px; border-radius: 14px;
  padding: 13px 22px; font-weight: 700; font-size: 15px; transition: all 0.2s; border: 2px solid transparent;
}
.yb-btn--primary { background: var(--yb-primary); color: var(--yb-on-primary); }
.yb-btn--primary:hover { background: #ff8247; box-shadow: 0 6px 18px rgba(229, 86, 26, 0.35); }
.yb-btn--ghost { border-color: var(--yb-border); color: var(--yb-text); background: #fff; }
.yb-btn--ghost:hover { border-color: var(--yb-primary); color: var(--yb-primary); }
.yb-note { font-size: 12px; color: var(--yb-text-light); }

.yb-phone {
  width: 270px; border-radius: 40px; background: #0b0e13; padding: 10px;
  box-shadow: 0 30px 60px rgba(11, 14, 19, 0.28), 0 0 0 2px #2a3341;
}
.yb-phone img { border-radius: 31px; width: 100%; }
@media (max-width: 480px) { .yb-benefits { grid-template-columns: 1fr; } }

/* Hero：滿版地圖舞台（方向 1・Studio Dumbar「系統即畫面」）——愛心路線描線，經過的六角格依序點亮 */
.yb-hero2 { position: relative; isolation: isolate; display: flex; flex-direction: column; overflow: hidden; background: var(--yb-dark); color: #f4f6f9;
  min-height: max(640px, calc(100vh - 96px)); min-height: max(640px, calc(100svh - 96px)); }
.yb-stage { position: absolute; inset: 0; width: 100%; height: 100%; z-index: -2; }
.yb-hero2::after { content: ""; position: absolute; inset: 0; z-index: -1; pointer-events: none;
  background: linear-gradient(90deg, rgba(11,14,19,.92) 0%, rgba(11,14,19,.55) 38%, rgba(11,14,19,0) 62%),
              linear-gradient(0deg, rgba(11,14,19,.85), rgba(11,14,19,0) 28%); }
.yb-hud { position: absolute; left: clamp(20px, 4vw, 56px); top: 24px; display: flex; gap: 10px; font-family: "Barlow Condensed", sans-serif; }
.yb-chip { background: rgba(23,28,36,.78); backdrop-filter: blur(8px); -webkit-backdrop-filter: blur(8px); border: 1px solid var(--yb-dark-border); border-radius: 12px; padding: 8px 14px; }
.yb-chip b { display: block; font-size: 34px; line-height: 1; color: var(--yb-amber); font-weight: 700; }
.yb-chip--l b { color: var(--yb-lime); }
.yb-chip span { font-family: "Noto Sans TC", sans-serif; font-size: 12px; color: #9ba5b3; }
.yb-hero2-copy { margin-top: auto; padding: 120px clamp(20px, 4vw, 56px) clamp(28px, 6vh, 64px); max-width: min(760px, 92vw); }
.yb-hero2 h1 { font-weight: 900; line-height: 1.02; font-size: clamp(44px, 8vw, 120px); letter-spacing: -.02em; color: #f4f6f9; }
.yb-hero2 h1 span { display: block; }
.yb-hero2 h1 .b { color: var(--yb-lime); }
.yb-hero2-sub { margin: 22px 0 28px; font-size: clamp(16px, 1.5vw, 20px); line-height: 1.75; color: #c3cbd6; max-width: 34em; }
.yb-hero2 .yb-btn--primary { padding: 0 24px; min-height: 48px; justify-content: center; font-weight: 900; font-size: 16px; }
.yb-hero2 .yb-btn--ghost { background: transparent; color: #f4f6f9; border-color: #4a5565; padding: 0 24px; min-height: 48px; justify-content: center; font-weight: 900; font-size: 16px; }
.yb-hero2 .yb-btn--ghost:hover { border-color: var(--yb-lime); color: var(--yb-lime); }
.yb-hero2 .yb-note { margin-top: 14px; font-size: 13px; color: #9ba5b3; }
.yb-hero2-phone { position: absolute; right: clamp(20px, 5vw, 80px); bottom: clamp(28px, 7vh, 72px); width: clamp(180px, 17vw, 250px); border-radius: 30px; padding: 7px; background: #0b0e13; box-shadow: 0 0 0 2px #2a3341, 0 30px 70px rgba(0,0,0,.6); transform: rotate(4deg); }
.yb-hero2-phone img { width: 100%; height: auto; display: block; border-radius: 24px; }
@media (max-width: 860px) {
  .yb-hero2::after { background: linear-gradient(0deg, rgba(11,14,19,.95) 0%, rgba(11,14,19,.7) 45%, rgba(11,14,19,.1) 75%); }
  .yb-hero2-phone { display: none; }
  .yb-hero2-copy { padding-bottom: 36px; }
}

/* Hero 之後的簡介帶 */
.yb-intro { padding: 56px 0 8px; }
.yb-intro .yb-hero-definition { max-width: 820px; margin: 0 auto 28px; }
.yb-intro .yb-benefits { max-width: 820px; margin: 0 auto; }

/* ---------- 深色三法區塊（對應參考頁的 AI 辨識區） ---------- */
.yb-dark-section { background: var(--yb-dark); padding: 72px 0; }
.yb-dark-section .yb-section-title { color: #fff; }
.yb-dark-section .yb-section-sub { color: #9ba5b3; }
.yb-ways { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 40px; }
.yb-way {
  background: var(--yb-dark-card); border: 1px solid var(--yb-dark-border); border-radius: 18px;
  padding: 28px 24px; color: #c3cbd6;
}
.yb-way .num { font-family: "Barlow Condensed", "Noto Sans TC", sans-serif; font-size: 44px; font-weight: 800; color: var(--yb-lime); line-height: 1; }
.yb-way h3 { color: #fff; font-size: 19px; margin: 12px 0 8px; }
.yb-way p { font-size: 14px; line-height: 1.75; }
@media (max-width: 860px) { .yb-ways { grid-template-columns: 1fr; } }

/* ---------- 通用區塊 ---------- */
.yb-section { padding: 80px 0; }
.yb-section--gray { background: var(--yb-bg); }
.yb-section--warm { background: linear-gradient(180deg, #fff8f1, #fff); }
.yb-section-title { font-size: 32px; font-weight: 900; color: var(--yb-text); text-align: center; line-height: 1.3; }
.yb-section-sub { text-align: center; font-size: 16px; max-width: 640px; margin: 12px auto 0; }
.yb-kicker { display: block; text-align: center; color: var(--yb-primary-text); font-weight: 700; font-size: 13px; letter-spacing: 0.1em; margin-bottom: 8px; }

/* 功能卡 */
.yb-features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 44px; }
.yb-card {
  background: var(--yb-card); border: 1px solid var(--yb-border); border-radius: 18px; padding: 26px 24px;
  transition: transform 0.2s, box-shadow 0.2s;
}
.yb-card:hover { transform: translateY(-3px); box-shadow: 0 12px 30px rgba(15, 23, 42, 0.08); }
.yb-card .yb-icon { width: 46px; height: 46px; font-size: 24px; border-radius: 12px; margin-bottom: 14px; }
.yb-card h3 { font-size: 18px; color: var(--yb-text); margin-bottom: 8px; }
.yb-card p { font-size: 14px; line-height: 1.75; }
@media (max-width: 860px) { .yb-features { grid-template-columns: 1fr; } }
@media (min-width: 861px) and (max-width: 1000px) { .yb-features { grid-template-columns: repeat(2, 1fr); } }

/* 左右交錯的展示列 */
.yb-showcase { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.yb-showcase + .yb-showcase { margin-top: 72px; }
.yb-showcase--rev .yb-showcase-text { order: 2; }
.yb-showcase h3 { font-size: 28px; color: var(--yb-text); line-height: 1.35; margin: 4px 0 14px; }
.yb-showcase p { font-size: 16px; line-height: 1.8; margin-bottom: 14px; }
.yb-checks li { position: relative; padding-left: 28px; margin-bottom: 10px; font-size: 15px; }
.yb-checks li::before {
  content: "✓"; position: absolute; left: 0; top: 1px; width: 20px; height: 20px; border-radius: 50%;
  background: var(--yb-primary); color: var(--yb-on-primary); font-size: 12px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.yb-shot { display: flex; justify-content: center; }
.yb-shot .yb-phone { width: 250px; }
@media (max-width: 860px) {
  .yb-showcase { grid-template-columns: 1fr; gap: 28px; }
  .yb-showcase--rev .yb-showcase-text { order: 0; }
  .yb-showcase h3 { font-size: 24px; }
  .yb-section { padding: 56px 0; }
  .yb-section-title { font-size: 26px; }
}

/* 數字帶 */
.yb-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 40px; }
.yb-stat { text-align: center; background: #fff; border: 1px solid var(--yb-border); border-radius: 16px; padding: 22px 12px; }
.yb-stat b { display: block; font-size: 34px; font-weight: 900; color: var(--yb-primary-large); line-height: 1.1; }
.yb-stat span { font-size: 13px; }
@media (max-width: 700px) { .yb-stats { grid-template-columns: repeat(2, 1fr); } }

/* 三種人 */
.yb-personas { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 44px; }
.yb-persona { background: #fff; border: 1px solid var(--yb-border); border-radius: 18px; padding: 28px 24px; text-align: center; }
.yb-persona .face { font-size: 40px; margin-bottom: 8px; }
.yb-persona h3 { font-size: 18px; color: var(--yb-text); margin-bottom: 8px; }
.yb-persona p { font-size: 14px; line-height: 1.75; }
@media (max-width: 860px) { .yb-personas { grid-template-columns: 1fr; } }

/* 步驟 */
.yb-steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-top: 44px; counter-reset: s; }
.yb-step { text-align: center; padding: 0 6px; }
.yb-step::before {
  counter-increment: s; content: counter(s);
  display: flex; align-items: center; justify-content: center; margin: 0 auto 14px;
  width: 52px; height: 52px; border-radius: 50%; background: var(--yb-primary); color: var(--yb-on-primary);
  font-size: 22px; font-weight: 900; box-shadow: 0 6px 16px rgba(255, 107, 44, 0.35);
}
.yb-step h3 { font-size: 17px; color: var(--yb-text); margin-bottom: 6px; }
.yb-step p { font-size: 14px; line-height: 1.7; }
@media (max-width: 860px) { .yb-steps { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .yb-steps { grid-template-columns: 1fr; } }

/* 比較表 */
.yb-table-wrap { overflow-x: auto; margin-top: 40px; border-radius: 16px; border: 1px solid var(--yb-border); background: #fff; }
.yb-table { width: 100%; border-collapse: collapse; min-width: 560px; font-size: 14px; }
.yb-table th, .yb-table td { padding: 14px 16px; text-align: center; border-bottom: 1px solid var(--yb-border); }
.yb-table th:first-child, .yb-table td:first-child { text-align: left; color: var(--yb-text); font-weight: 600; }
.yb-table thead th { background: var(--yb-bg); color: var(--yb-text); font-size: 14px; }
.yb-table thead th.me { background: var(--yb-primary); color: var(--yb-on-primary); }
.yb-table td.me { background: var(--yb-primary-light); color: var(--yb-primary-text); font-weight: 700; }
.yb-table tr:last-child td { border-bottom: 0; }

/* FAQ */
.yb-faq { max-width: 760px; margin: 40px auto 0; }
.yb-faq details { background: #fff; border: 1px solid var(--yb-border); border-radius: 14px; margin-bottom: 12px; padding: 0 20px; }
.yb-faq summary { cursor: pointer; padding: 18px 0; font-weight: 700; color: var(--yb-text); font-size: 16px; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
.yb-faq summary::-webkit-details-marker { display: none; }
.yb-faq summary::after { content: "+"; color: var(--yb-primary-text); font-size: 22px; line-height: 1; font-weight: 700; }
.yb-faq details[open] summary::after { content: "–"; }
.yb-faq details p { padding: 0 0 18px; font-size: 14px; line-height: 1.8; }

/* 下載 CTA */
.yb-cta-section { background: var(--yb-dark); text-align: center; padding: 84px 0; }
.yb-cta-title { font-size: 40px; font-weight: 900; color: #fff; }
.yb-cta-title em { font-style: normal; color: var(--yb-lime); }
.yb-cta-section p { color: #9ba5b3; margin: 12px auto 28px; max-width: 540px; }
.yb-cta-section .yb-cta-row { justify-content: center; }
.yb-cta-section .yb-cta-hint { font-size: 13px; margin: 14px auto 0; }
.yb-cta-section .yb-btn--ghost { background: transparent; color: #fff; border-color: #4a5565; }
.yb-cta-section .yb-btn--ghost:hover { color: var(--yb-lime); border-color: var(--yb-lime); }

/* 下載 QR（只在桌機顯示；手機直接點上方按鈕） */
.yb-qr-row { display: flex; justify-content: center; gap: 28px; margin-top: 36px; }
.yb-qr-item { text-align: center; }
.yb-qr-item img { width: 132px; height: 132px; padding: 8px; background: #fff; border-radius: 14px; image-rendering: pixelated; }
.yb-qr-item figcaption { margin-top: 10px; font-size: 13px; line-height: 1.5; color: #c3cbd6; }
@media (max-width: 767px) { .yb-qr-row { display: none; } }

/* 版本紀錄 */
.yb-changelog { max-width: 760px; margin: 36px auto 0; background: #fff; border: 1px solid var(--yb-border); border-radius: 18px; padding: 24px 28px; }
.yb-changelog .date { display: inline-block; font-size: 12px; font-weight: 700; color: var(--yb-primary-dark); background: var(--yb-primary-alpha); border-radius: 12px; padding: 3px 12px; margin-bottom: 14px; }
.yb-changelog li { position: relative; padding-left: 26px; margin-bottom: 10px; font-size: 14px; line-height: 1.7; }
.yb-changelog li::before { content: "✓"; position: absolute; left: 0; color: var(--yb-primary); font-weight: 800; }

/* Footer */
.yb-footer { padding: 32px 0; text-align: center; font-size: 13px; color: var(--yb-text-light); border-top: 1px solid var(--yb-border); }

.yb-announce-bar a { text-decoration: underline; }

.yb-en-summary { max-width: 760px; margin: 16px auto 0; font-size: 14px; line-height: 1.7; color: var(--yb-text-light); text-align: center; }
.yb-footer-links { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 20px; margin-bottom: 12px; }
.yb-footer-links a { color: inherit; text-decoration: underline; }
.yb-footer p { margin: 0; }