/* Summer — fresh teal / lime / coral (youthful) */
html[data-theme="summer"]{
  --color-bg:#F3F7F8;
  --color-bg-elevated:#FFFFFF;
  --color-surface:#FFFFFF;
  --color-surface-2:#EAF4F6;
  --color-text:#0F1C1F;
  --color-muted:#5A6F76;
  --color-border:#D2E4E9;
  --color-primary:#0D9488;
  --color-primary-dark:#0F766E;
  --color-primary-soft:rgba(13,148,136,.12);
  --color-secondary:#22C55E;
  --color-accent:#FBBF24;
  --color-cta:#F97316;
  --color-cta-dark:#EA580C;
  --color-chip:#E6F7F5;
  --color-hero-from:#042F2E;
  --color-hero-mid:#0F766E;
  --color-hero-to:#14B8A6;
  --color-hero-glow:rgba(45,212,191,.35);
  --color-footer-bg:#042F2E;
  --color-footer-text:#CCFBF1;
  --color-nav-bg:rgba(243,247,248,.78);
  --grad-brand:linear-gradient(135deg,#0D9488 0%,#14B8A6 45%,#FBBF24 100%);
  --grad-cta:linear-gradient(135deg,#F97316,#FB923C);
  --grad-card:linear-gradient(160deg,rgba(255,255,255,.9),rgba(230,247,245,.65));
  --font-display:"Outfit","Noto Sans TC","Noto Sans",system-ui,sans-serif;
  --font-sans:"DM Sans","Noto Sans TC","Noto Sans","Noto Naskh Arabic",system-ui,sans-serif;
  --radius:18px;
  --radius-sm:12px;
  --radius-lg:28px;
  --shadow:0 4px 24px rgba(15,28,31,.06);
  --shadow-lg:0 20px 50px rgba(15,28,31,.12);
  --shadow-glow:0 12px 40px rgba(13,148,136,.25);
}