/* Koko Agent — the app's "Mist" theme (Outfit + Fraunces, teal #0f766e). The SDK band is its developer counterpart (#0A84FF). */
:root {
  --bg: #f3f6f8;
  --bg-2: #e9f0f1;
  --surface: rgba(255, 255, 255, 0.82);
  --line: rgba(28, 48, 56, 0.12);
  --text: #1a2b33;
  --muted: #5a717c;
  --accent: #0f766e;
  --accent-2: #0d9488;
  --on-accent: #fff;
  --nav-bg: rgba(243, 246, 248, 0.78);
  --radius: 20px;
  --font: 'Outfit', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
  --font-display: 'Fraunces', 'Songti SC', 'Noto Serif SC', 'STSong', serif;
}

body { background: radial-gradient(80% 60% at 100% 0%, rgba(13, 148, 136, 0.08), transparent 60%), var(--bg); }
h1, h2, h3 { font-weight: 560; letter-spacing: -0.015em; }
.lang-zh h1, .lang-zh h2 { font-weight: 600; }
.card h3 { font-family: var(--font); font-weight: 600; letter-spacing: 0; }
.eyebrow { font-family: var(--font); letter-spacing: 0.12em; }
.btn--ghost { background: rgba(255, 255, 255, 0.7); }

.hero { padding: 140px 0 80px; }
.hero__grid { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr); gap: 56px; align-items: center; }
.pill { display: inline-flex; align-items: center; gap: 8px; padding: 6px 14px; border-radius: 999px; background: rgba(15, 118, 110, 0.1); color: var(--accent); font-size: 13.5px; font-weight: 600; }
.pill__dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent-2); animation: pulse 2s infinite; }
@keyframes pulse { 50% { box-shadow: 0 0 0 6px rgba(13, 148, 136, 0); } 0% { box-shadow: 0 0 0 0 rgba(13, 148, 136, 0.45); } }
.hero__title { margin-top: 24px; font-size: clamp(40px, 5.2vw, 74px); line-height: 1.08; }
.hero__title span { display: block; }
.hero__title .accent { color: var(--accent); font-style: italic; }
.lang-zh .hero__title .accent { font-style: normal; }
.hero__copy .lead { margin-top: 26px; }
.hero__visual { position: relative; margin: 0; border-radius: 28px; overflow: visible; }
.hero__visual picture img { width: 100%; aspect-ratio: 4 / 3.4; object-fit: cover; object-position: 55% 50%; border-radius: 28px; box-shadow: 0 50px 100px -50px rgba(20, 40, 50, 0.45); }

.chat { position: absolute; left: -28px; bottom: -44px; width: min(380px, 88%); padding: 16px; border-radius: 22px; background: rgba(255, 255, 255, 0.86); backdrop-filter: blur(20px) saturate(160%); -webkit-backdrop-filter: blur(20px) saturate(160%); border: 1px solid rgba(255, 255, 255, 0.9); box-shadow: 0 30px 70px -30px rgba(20, 40, 50, 0.45); font-size: 14px; display: flex; flex-direction: column; gap: 10px; min-height: 300px; }
.chat__head { display: flex; align-items: center; gap: 8px; padding-bottom: 8px; border-bottom: 1px solid var(--line); }
.chat__head img { width: 24px; height: 24px; border-radius: 6px; }
.chat__live { width: 7px; height: 7px; border-radius: 50%; background: #2f9e6b; margin-left: auto; }
.chat [data-step] { opacity: 0; transform: translateY(8px); transition: opacity 0.45s var(--ease), transform 0.45s var(--ease); }
.chat [data-step].is-on { opacity: 1; transform: none; }
.chat__msg { padding: 10px 14px; border-radius: 16px; line-height: 1.5; }
.chat__msg--user { align-self: flex-end; max-width: 88%; background: #d7efe9; border-bottom-right-radius: 6px; }
.chat__msg--bot { display: flex; gap: 8px; background: #fff; border: 1px solid var(--line); border-bottom-left-radius: 6px; }
.chat__msg--bot svg { width: 18px; height: 18px; flex: none; color: #2f9e6b; margin-top: 2px; }
.chat__step { display: flex; align-items: center; gap: 10px; color: var(--muted); font-size: 13px; padding-left: 4px; }
.chat__spin { width: 12px; height: 12px; border-radius: 50%; border: 2px solid rgba(15, 118, 110, 0.25); border-top-color: var(--accent); animation: spin 0.9s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.chat__input { margin-top: auto; display: flex; align-items: center; gap: 8px; padding: 8px 8px 8px 14px; border-radius: 999px; background: #fff; border: 1px solid var(--line); color: var(--muted); font-size: 13px; }
.chat__input i { margin-left: auto; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; background: var(--accent); color: #fff; }
.chat__input svg { width: 15px; height: 15px; }

.card { backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); }
.can { position: relative; overflow: hidden; }
.can::after { content: '“'; position: absolute; right: 18px; top: -6px; font: 400 88px/1 var(--font-display); color: rgba(15, 118, 110, 0.12); }
.can__q { margin-top: 8px; font-family: var(--font-display); font-size: 17px !important; color: var(--text) !important; line-height: 1.5; }

.loop { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; position: relative; }
.loop li { position: relative; padding: 28px; border-radius: var(--radius); background: var(--surface); border: 1px solid var(--line); min-width: 0; }
.loop li:not(:last-child)::after { content: '→'; position: absolute; right: -16px; top: 34px; color: var(--accent); font-size: 18px; z-index: 1; }
.loop__n { display: inline-grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; background: var(--accent); color: #fff; font-weight: 600; margin-bottom: 18px; }
.loop h3 { font-size: 24px; margin-bottom: 8px; }
.loop p { color: var(--muted); font-size: 15.5px; }
.learn { display: flex; gap: 20px; align-items: center; margin-top: 24px; padding: 26px 30px; border-radius: var(--radius); background: linear-gradient(120deg, #0f766e, #0d9488); color: #fff; }
.learn__ic { width: 52px; height: 52px; flex: none; border-radius: 16px; display: grid; place-items: center; background: rgba(255, 255, 255, 0.16); }
.learn__ic svg { width: 26px; height: 26px; }
.learn h3 { font-size: 22px; margin-bottom: 4px; }
.learn p { color: rgba(255, 255, 255, 0.82); }

.simple { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: 56px; align-items: start; }
.simple__list { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 28px 32px; }
.simple__list li { display: flex; gap: 14px; min-width: 0; }
.simple__list svg { width: 22px; height: 22px; flex: none; color: var(--accent); margin-top: 3px; }
.simple__list strong { display: block; font-size: 18px; margin-bottom: 4px; }
.simple__list span { color: var(--muted); font-size: 15.5px; }

.platforms { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; margin-top: 48px; padding-top: 36px; border-top: 1px solid var(--line); text-align: center; }
.platforms strong { display: block; font: 560 28px var(--font-display); }
.platforms span { color: var(--muted); font-size: 14.5px; }

/* SDK band */
.sdk { --accent: #0a84ff; --accent-2: #5ac8fa; --text: #eaf2ff; --muted: #8fa3bf; --line: rgba(255, 255, 255, 0.1); --surface: rgba(255, 255, 255, 0.04); --font-display: 'Inter', -apple-system, 'PingFang SC', sans-serif;
  position: relative; padding: clamp(90px, 12vw, 150px) 0; color: var(--text); background: radial-gradient(60% 50% at 80% 0%, rgba(10, 132, 255, 0.25), transparent 60%), radial-gradient(40% 40% at 0% 100%, rgba(90, 200, 250, 0.12), transparent 60%), #060b16; }
.sdk h2, .sdk h3 { font-family: var(--font-display); font-weight: 700; letter-spacing: -0.025em; }
.lang-zh .sdk h2 { letter-spacing: 0; }
.sdk__head { max-width: 820px; margin-bottom: 56px; }
.sdk__k { display: inline-grid; place-items: center; width: 26px; height: 26px; margin-right: 10px; border-radius: 7px; background: var(--accent); color: #fff; font: 700 14px var(--font-display); vertical-align: -7px; }
.sdk .eyebrow { color: var(--accent-2); }
.sdk__grid { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.6fr); gap: 48px; align-items: center; }
.sdk__grid .term + .term { margin-top: 16px; }
.sdk .term { background: rgba(3, 7, 15, 0.9); border-color: rgba(10, 132, 255, 0.25); }
.sdk .term pre { color: #c9d7ef; }
.sdk .term .k { color: #ff7ab2; } .sdk .term .s { color: #fc6a5d; } .sdk .term .f { color: #67b7ff; } .sdk .term .t { color: #5ac8fa; } .sdk .term .c { color: #6c7a90; }
.sdk__phone { display: flex; justify-content: center; }
.sdk__phone .phone { width: 260px; box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08) inset, 0 0 80px -20px rgba(10, 132, 255, 0.6); }
.sdk__features { margin-top: 64px; }
.sdk .card { backdrop-filter: none; }
.sdk .card h3 { font-size: 18px; }
.sdk__bottom { display: grid; grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.7fr); gap: 40px; margin: 64px 0; align-items: start; }
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 24px; }
.steps li { border-top: 2px solid var(--line); padding-top: 20px; min-width: 0; }
.steps__n { font: 600 13px var(--mono); color: var(--accent-2); }
.steps h3 { font-size: 19px; margin: 8px 0 6px; }
.steps p { color: var(--muted); font-size: 15px; }
.gateways { display: grid; gap: 12px; padding: 22px; border-radius: 18px; border: 1px solid var(--line); background: var(--surface); }
.gateways div { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.gateways span { font-size: 13px; color: var(--muted); }
.gateways code { font-size: 14px; color: var(--accent-2); overflow-wrap: anywhere; }
.gateways p { font-size: 13.5px; color: var(--muted); padding-top: 10px; border-top: 1px solid var(--line); }
.sdk .stats { text-align: center; }
.sdk .stats dt { color: #fff; }
.sdk .btn--primary:hover { box-shadow: 0 10px 30px -8px var(--accent); }

@media (max-width: 1000px) {
  .hero__grid, .simple, .sdk__grid, .sdk__bottom { grid-template-columns: minmax(0, 1fr); }
  .chat { left: 16px; bottom: -48px; }
  .hero { padding-bottom: 120px; }
  .loop { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .loop li::after { display: none; }
}
@media (max-width: 640px) {
  .hero { padding-top: 110px; padding-bottom: 40px; }
  .hero__visual picture img { aspect-ratio: 4 / 3; }
  .chat { position: relative; left: auto; bottom: auto; width: auto; margin: -64px 12px 0; min-height: 280px; }
  .loop, .simple__list, .steps { grid-template-columns: minmax(0, 1fr); }
  .platforms strong { font-size: 22px; }
  .learn { flex-direction: column; align-items: flex-start; }
}