/* ============ 减肥日记 · 设计系统 ============ */
:root{
  --green:#2F9E62;
  --green-dark:#1F7A48;
  --green-light:#E4F3EA;
  --orange:#F2994A;
  --orange-dark:#E07B2F;
  --pebble:#FAF9F6;
  --pebble-dark:#F1EEE7;
  --ink:#1A2B22;
  --muted:#6B7B72;
  --line:#E4E0D6;
  --red:#E05D5D;
  --white:#fff;
  --font-heading:'Outfit','Noto Sans SC',sans-serif;
  --font-body:'Inter','Noto Sans SC',-apple-system,sans-serif;
  --radius:16px;
  --radius-lg:24px;
  --max-width:1100px;
  --shadow:0 4px 20px rgba(26,43,34,.08);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--font-body);background:var(--pebble);color:var(--ink);-webkit-font-smoothing:antialiased;line-height:1.6}
a{text-decoration:none;color:inherit}
img{max-width:100%}

/* ============ Loader ============ */
.loader{position:fixed;inset:0;background:var(--pebble);z-index:9999;display:flex;align-items:center;justify-content:center;transition:opacity .4s,visibility .4s}
.loader::after{content:'';width:40px;height:40px;border-radius:50%;border:3px solid var(--green-light);border-top-color:var(--green);animation:spin 1s linear infinite}
.loader.done{opacity:0;visibility:hidden}
@keyframes spin{to{transform:rotate(360deg)}}

/* ============ Nav ============ */
.nav{position:fixed;top:0;left:0;right:0;z-index:100;display:flex;align-items:center;justify-content:space-between;padding:18px 32px;background:rgba(250,249,246,.85);backdrop-filter:blur(12px);border-bottom:1px solid transparent;transition:all .3s}
.nav.scrolled{background:rgba(250,249,246,.97);box-shadow:0 2px 16px rgba(26,43,34,.08);padding:12px 32px}
.nav-logo{display:flex;align-items:center;gap:10px;font-family:var(--font-heading);font-weight:900;font-size:18px;color:var(--green-dark)}
.nav-logo-mark{width:34px;height:34px;border-radius:10px;background:var(--green);color:var(--white);display:flex;align-items:center;justify-content:center}
.nav-logo-mark svg{width:20px;height:20px}
.nav-links{display:flex;align-items:center;gap:6px;list-style:none}
.nav-links a{padding:8px 14px;border-radius:10px;font-size:14px;font-weight:500;color:var(--muted);transition:all .2s}
.nav-links a:hover{color:var(--green-dark);background:var(--green-light)}
.nav-links .nav-btn{background:var(--green);color:var(--white);font-weight:600}
.nav-links .nav-btn:hover{background:var(--green-dark);color:var(--white)}
.nav-mobile{display:none;background:none;border:none;cursor:pointer;width:42px;height:42px;flex-direction:column;align-items:center;justify-content:center;gap:5px}
.nav-mobile span{width:22px;height:2px;background:var(--ink);border-radius:2px;transition:all .3s}
.nav-mobile.active span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-mobile.active span:nth-child(2){opacity:0}
.nav-mobile.active span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

/* ============ Hero ============ */
.hero{position:relative;padding:140px 32px 90px;background:linear-gradient(150deg,var(--green-dark) 0%,var(--green) 55%,#57B57F 100%);overflow:hidden;color:var(--white);text-align:center}
.hero-bg{position:absolute;inset:0;opacity:.12;background-image:radial-gradient(circle at 20% 30%,#fff 1px,transparent 1px),radial-gradient(circle at 70% 60%,#fff 1px,transparent 1px),radial-gradient(circle at 40% 80%,#fff 1px,transparent 1px),radial-gradient(circle at 85% 20%,#fff 1px,transparent 1px),radial-gradient(circle at 10% 70%,#fff 1px,transparent 1px);background-size:140px 140px}
.hero-inner{position:relative;max-width:var(--max-width);margin:0 auto}
.hero-kicker{font-family:var(--font-heading);font-size:13px;letter-spacing:4px;opacity:.7;margin-bottom:14px;font-weight:600}
.hero h1{font-family:var(--font-heading);font-size:clamp(44px,7vw,76px);font-weight:900;letter-spacing:-2px;line-height:1.05;margin-bottom:16px}
.hero-sub{font-size:17px;line-height:1.8;opacity:.9;margin-bottom:32px}
.hero-actions{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.btn-primary{display:inline-flex;align-items:center;gap:8px;background:var(--white);color:var(--green-dark);font-weight:700;font-size:15px;padding:13px 28px;border-radius:50px;border:none;cursor:pointer;transition:all .25s;box-shadow:0 4px 16px rgba(0,0,0,.15)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 8px 24px rgba(0,0,0,.2)}
.btn-ghost{display:inline-flex;align-items:center;gap:8px;background:transparent;color:var(--white);font-weight:600;font-size:15px;padding:13px 28px;border-radius:50px;border:2px solid rgba(255,255,255,.5);cursor:pointer;transition:all .25s}
.btn-ghost:hover{background:rgba(255,255,255,.15);border-color:#fff}

/* ============ Section ============ */
.section{padding:70px 24px}
.section-alt{background:var(--pebble-dark)}
.section-inner{max-width:var(--max-width);margin:0 auto}
.section-head{text-align:center;margin-bottom:36px}
.sec-label{font-size:12px;font-weight:700;letter-spacing:3px;text-transform:uppercase;color:var(--green)}
.section-head h2{font-family:var(--font-heading);font-size:clamp(28px,4vw,38px);font-weight:800;letter-spacing:-1px;color:var(--ink);margin-top:6px}
.head-actions{display:flex;gap:10px;justify-content:center;margin-top:16px}
.btn-small{background:var(--white);border:1px solid var(--line);color:var(--muted);font-size:13px;font-weight:600;padding:7px 16px;border-radius:50px;cursor:pointer;transition:all .2s}
.btn-small:hover{color:var(--green-dark);border-color:var(--green)}
.btn-danger:hover{color:var(--red);border-color:var(--red)}

/* ============ Stats ============ */
.stats-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px}
.stat-card{background:var(--white);border:1px solid var(--line);border-radius:var(--radius);padding:24px 16px;text-align:center;transition:all .25s}
.stat-card:hover{transform:translateY(-4px);box-shadow:var(--shadow)}
.stat-card.highlight{background:linear-gradient(150deg,var(--green),var(--green-dark));border-color:transparent;color:var(--white)}
.stat-icon{font-size:26px;margin-bottom:8px}
.stat-val{font-family:var(--font-heading);font-size:32px;font-weight:900;line-height:1.1}
.stat-card.highlight .stat-val{color:#fff}
.stat-lbl{font-size:12px;color:var(--muted);margin-top:4px}
.stat-card.highlight .stat-lbl{color:rgba(255,255,255,.85)}
.stat-sub{font-size:11px;color:var(--line);margin-top:6px}
.stat-card.highlight .stat-sub{color:rgba(255,255,255,.6)}

/* ============ Chart ============ */
.chart-card{background:var(--white);border:1px solid var(--line);border-radius:var(--radius-lg);padding:28px}
.chart-toolbar{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;margin-bottom:20px}
.chart-title{font-family:var(--font-heading);font-weight:700;font-size:16px}
.chart-legend{display:flex;gap:16px;font-size:12px;color:var(--muted)}
.chart-legend .dot{display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:5px}
.chart-wrap{width:100%;overflow-x:auto}
.chart-wrap canvas{display:block;width:100%;min-width:560px;height:auto}
.chart-note{font-size:12px;color:var(--muted);margin-top:14px;text-align:center}

/* ============ Check-in ============ */
.checkin-grid{display:grid;grid-template-columns:1.4fr 1fr;gap:24px}
.checkin-form-card,.checkin-tip-card{background:var(--white);border:1px solid var(--line);border-radius:var(--radius-lg);padding:28px}
.checkin-form-card h3,.checkin-tip-card h3{font-family:var(--font-heading);font-size:18px;font-weight:800;margin-bottom:20px;color:var(--green-dark)}
.form-row{margin-bottom:16px}
.form-row label{display:block;font-size:13px;font-weight:600;color:var(--muted);margin-bottom:6px}
.form-row input[type=date],.form-row input[type=number],.form-row input[type=text],.form-row textarea{width:100%;padding:11px 14px;border:1.5px solid var(--line);border-radius:10px;font-size:14px;font-family:var(--font-body);background:var(--pebble);color:var(--ink);transition:border-color .2s;outline:none}
.form-row input:focus,.form-row textarea:focus{border-color:var(--green);background:#fff}
.form-row textarea{resize:vertical}
.pill-group{display:flex;flex-wrap:wrap;gap:8px}
.pill{padding:7px 14px;border-radius:50px;border:1.5px solid var(--line);background:var(--pebble);font-size:13px;cursor:pointer;transition:all .2s;color:var(--muted)}
.pill:hover{border-color:var(--green)}
.pill.active{background:var(--green);color:#fff;border-color:var(--green)}
.btn-block{width:100%;justify-content:center;margin-top:4px}
.form-hint{font-size:13px;margin-top:10px;color:var(--green);min-height:20px;font-weight:500}
.tip-box{background:var(--green-light);border-radius:12px;padding:16px;font-size:14px;line-height:1.7;color:var(--green-dark)}
.goal-progress-card{margin-top:20px;background:var(--pebble);border-radius:12px;padding:18px}
.goal-progress-card h4{font-family:var(--font-heading);font-size:15px;margin-bottom:12px;color:var(--ink)}
.progress-track{height:12px;background:var(--line);border-radius:50px;overflow:hidden}
.progress-fill{height:100%;background:linear-gradient(90deg,var(--green),var(--orange));border-radius:50px;transition:width .6s ease}
.progress-text{font-size:13px;color:var(--muted);margin-top:8px}

/* ============ Timeline ============ */
.timeline{max-width:760px;margin:0 auto}
.timeline-empty{text-align:center;color:var(--muted);padding:40px 20px;background:var(--white);border:1px dashed var(--line);border-radius:var(--radius);font-size:14px}
.tl-item{display:flex;gap:18px;background:var(--white);border:1px solid var(--line);border-radius:var(--radius);padding:18px 20px;margin-bottom:14px;position:relative;transition:all .2s}
.tl-item:hover{box-shadow:var(--shadow)}
.tl-date{flex-shrink:0;width:86px;text-align:center;padding:10px 6px;background:var(--green-light);border-radius:10px}
.tl-date .d{font-family:var(--font-heading);font-size:22px;font-weight:900;color:var(--green-dark);line-height:1}
.tl-date .m{font-size:11px;color:var(--green-dark);margin-top:3px}
.tl-body{flex:1}
.tl-weight{font-family:var(--font-heading);font-size:20px;font-weight:900;color:var(--ink)}
.tl-weight .delta{font-size:14px;margin-left:6px;font-weight:700}
.delta.down{color:var(--green)}
.delta.up{color:var(--red)}
.delta.flat{color:var(--muted)}
.tl-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}
.tl-tag{font-size:11px;padding:3px 10px;border-radius:50px;background:var(--pebble);color:var(--muted);border:1px solid var(--line)}
.tl-tag.sport{background:var(--green-light);color:var(--green-dark);border-color:transparent}
.tl-note{font-size:13px;color:var(--muted);margin-top:6px}
.tl-del{position:absolute;top:12px;right:12px;background:none;border:none;color:var(--line);font-size:16px;cursor:pointer;opacity:0;transition:opacity .2s}
.tl-item:hover .tl-del{opacity:1}
.tl-del:hover{color:var(--red)}

/* ============ Goal ============ */
.goal-card{max-width:480px;margin:0 auto;background:var(--white);border:1px solid var(--line);border-radius:var(--radius-lg);padding:32px}

/* ============ Footer ============ */
.footer{background:var(--green-dark);color:rgba(255,255,255,.85);padding:48px 24px 24px;text-align:center}
.footer-logo{display:flex;align-items:center;justify-content:center;gap:10px;font-family:var(--font-heading);font-weight:800;font-size:20px;color:#fff;margin-bottom:12px}
.footer p{font-size:14px;opacity:.8;margin-bottom:24px}
.footer-bottom{font-size:12px;opacity:.5;border-top:1px solid rgba(255,255,255,.15);padding-top:20px}

/* ============ Reveal ============ */
.reveal{opacity:0;transform:translateY(24px);transition:opacity .6s ease,transform .6s ease}
.reveal.visible{opacity:1;transform:translateY(0)}

/* ============ Responsive ============ */
@media(max-width:968px){
  .stats-grid{grid-template-columns:repeat(3,1fr)}
  .checkin-grid{grid-template-columns:1fr}
}
@media(max-width:600px){
  .nav{padding:14px 18px}
  .nav-mobile{display:flex}
  .nav-links{position:fixed;top:62px;left:0;right:0;flex-direction:column;background:var(--pebble);padding:16px;gap:4px;box-shadow:0 8px 24px rgba(26,43,34,.1);transform:translateY(-130%);transition:transform .3s;border-radius:0 0 16px 16px}
  .nav-links.open{transform:translateY(0)}
  .nav-links a{display:block;text-align:center;padding:12px}
  .hero{padding:120px 18px 70px}
  .stats-grid{grid-template-columns:repeat(2,1fr)}
  .hero-actions{flex-direction:column;align-items:center}
  .tl-date{width:70px}
}