/* ===== RESET ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:1rem}
body{min-height:100vh;background:var(--bg-light);color:var(--text-dark);font-family:var(--font-body);font-size:1rem;line-height:1.6;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
img,svg,video{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
ul,ol{list-style:none}
button,input,select,textarea{font:inherit;color:inherit;border:none;background:none;cursor:pointer}
button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:2px solid var(--accent-orange);outline-offset:2px}
:focus-visible{outline:2px solid var(--accent-orange);outline-offset:2px}
h1,h2,h3,h4,h5,h6{font-family:var(--font-heading);font-weight:700;line-height:1.2}
/* ===== VARIABLES ===== */
:root{--primary-blue:#0A4DA4;--accent-orange:#E8622E;--gradient-primary:linear-gradient(135deg,#0A4DA4,#E8622E);--bg-light:#F5F7FA;--surface-glass:rgba(255,255,255,0.7);--text-dark:#1A1A2E;--text-light:#FFFFFF;--accent-green:#2ECC71;--border-subtle:#D0D5DD;--sidebar-width:260px;--topbar-height:60px;--font-heading:'Inter',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;--font-body:'Inter',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;--radius-sm:6px;--radius-md:12px;--radius-lg:20px;--shadow-sm:0 2px 8px rgba(0,0,0,0.06);--shadow-md:0 8px 24px rgba(0,0,0,0.10);--shadow-lg:0 16px 48px rgba(0,0,0,0.14);--transition-fast:0.2s ease;--transition-med:0.35s ease;--transition-slow:0.55s ease}
/* ===== SKIP LINK ===== */
.skip-link{position:fixed;top:-100%;left:1rem;z-index:9999;padding:0.75rem 1.5rem;background:var(--accent-orange);color:#fff;font-weight:600;border-radius:var(--radius-sm);transition:top var(--transition-fast)}
.skip-link:focus{top:1rem}
/* ===== HEADER – SIDEBAR ===== */
.site-header{position:fixed;top:0;left:0;z-index:1000;width:var(--sidebar-width);height:100vh;background:var(--primary-blue);color:var(--text-light);display:flex;flex-direction:column;transition:transform var(--transition-med);box-shadow:2px 0 20px rgba(0,0,0,0.15)}
.header-topbar{display:none;position:fixed;top:0;left:0;right:0;z-index:1001;height:var(--topbar-height);background:var(--primary-blue);padding:0 1.2rem;align-items:center;justify-content:space-between;box-shadow:0 2px 12px rgba(0,0,0,0.12)}
.header-logo{font-family:var(--font-heading);font-size:1.25rem;font-weight:800;text-transform:uppercase;letter-spacing:0.04em;color:var(--text-light)}
.header-toggle{width:40px;height:40px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;border-radius:var(--radius-sm);transition:background var(--transition-fast)}
.header-toggle:hover{background:rgba(255,255,255,0.10)}
.toggle-bar{display:block;width:24px;height:2.5px;background:var(--text-light);border-radius:2px;transition:transform var(--transition-med),opacity var(--transition-med)}
.header-toggle[aria-expanded="true"] .toggle-bar:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
.header-toggle[aria-expanded="true"] .toggle-bar:nth-child(2){opacity:0}
.header-toggle[aria-expanded="true"] .toggle-bar:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}
.header-sidebar{display:flex;flex-direction:column;height:100vh;padding:0;overflow-y:auto}
.sidebar-header{padding:2.2rem 1.8rem 1.2rem;border-bottom:1px solid rgba(255,255,255,0.10)}
.sidebar-logo{font-family:var(--font-heading);font-size:1.5rem;font-weight:800;text-transform:uppercase;letter-spacing:0.06em;color:var(--text-light);display:block;margin-bottom:0.4rem}
.sidebar-badge{display:inline-block;font-size:0.7rem;font-weight:600;text-transform:uppercase;letter-spacing:0.08em;color:var(--accent-orange);background:rgba(232,98,46,0.18);padding:0.2rem 0.7rem;border-radius:20px}
.sidebar-nav{flex:1;padding:1.5rem 0}
.nav-list{display:flex;flex-direction:column;gap:0.2rem}
.nav-item{padding:0 1rem}
.nav-link{display:block;padding:0.7rem 1rem;font-family:var(--font-heading);font-size:0.95rem;font-weight:600;color:rgba(255,255,255,0.75);border-radius:var(--radius-sm);transition:all var(--transition-fast);position:relative}
.nav-link:hover,.nav-link:focus-visible{color:var(--text-light);background:rgba(255,255,255,0.08)}
.nav-link[aria-current="page"]{color:var(--accent-orange);background:rgba(232,98,46,0.15);font-weight:700}
.nav-link[aria-current="page"]::before{content:'';position:absolute;left:0;top:50%;transform:translateY(-50%);width:3px;height:60%;background:var(--accent-orange);border-radius:0 3px 3px 0}
.sidebar-footer{padding:1.2rem 1.8rem 2rem;border-top:1px solid rgba(255,255,255,0.10);display:flex;flex-direction:column;gap:1rem}
.sidebar-locale{font-size:0.75rem;color:rgba(255,255,255,0.45);letter-spacing:0.04em;text-align:center}
.sidebar-overlay{display:none}
/* ===== BUTTONS ===== */
.btn{display:inline-flex;align-items:center;justify-content:center;padding:0.7rem 1.6rem;font-family:var(--font-heading);font-size:0.9rem;font-weight:700;border-radius:var(--radius-sm);transition:all var(--transition-fast);text-align:center;gap:0.5rem}
.btn-primary{background:var(--accent-orange);color:var(--text-light);box-shadow:0 4px 14px rgba(232,98,46,0.35)}
.btn-primary:hover,.btn-primary:focus-visible{background:#d45520;box-shadow:0 6px 20px rgba(232,98,46,0.45);transform:translateY(-1px)}
.btn-primary:active{transform:translateY(0)}
/* ===== MAIN CONTENT WRAPPER ===== */
#main-content{outline:none}
/* ===== FOOTER ===== */
.site-footer{background:var(--primary-blue);color:var(--text-light);position:relative;margin-left:var(--sidebar-width)}
.footer-wave{height:40px;background:linear-gradient(135deg,var(--primary-blue),var(--accent-orange));opacity:0.15;mask:linear-gradient(to right,transparent 0%,#000 20%,#000 80%,transparent 100%);-webkit-mask:linear-gradient(to right,transparent 0%,#000 20%,#000 80%,transparent 100%)}
.footer-inner{max-width:1200px;margin:0 auto;padding:2.5rem 2rem 1.8rem}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:2rem;margin-bottom:2rem}
.footer-logo{font-family:var(--font-heading);font-size:1.3rem;font-weight:800;text-transform:uppercase;letter-spacing:0.06em;color:var(--text-light);display:inline-block;margin-bottom:0.6rem}
.footer-desc{font-size:0.85rem;color:rgba(255,255,255,0.6);line-height:1.6;max-width:280px}
.footer-title{font-size:0.8rem;font-weight:700;text-transform:uppercase;letter-spacing:0.08em;color:rgba(255,255,255,0.4);margin-bottom:1rem}
.footer-links{display:flex;flex-direction:column;gap:0.6rem}
.footer-links a{font-size:0.9rem;color:rgba(255,255,255,0.7);transition:color var(--transition-fast)}
.footer-links a:hover,.footer-links a:focus-visible{color:var(--accent-orange)}
.footer-contact,.footer-phone,.footer-address{font-size:0.85rem;color:rgba(255,255,255,0.7);line-height:1.5}
.footer-bottom{border-top:1px solid rgba(255,255,255,0.08);padding-top:1.5rem;display:flex;flex-direction:column;gap:1rem}
.footer-trust{font-size:0.75rem;color:rgba(255,255,255,0.35);line-height:1.5;text-align:center}
.footer-meta{display:flex;justify-content:center;gap:2rem;font-size:0.75rem;color:rgba(255,255,255,0.4)}
.footer-icp,.footer-copyright{}
/* ===== COMMON LAYOUT ===== */
.page-wrapper{margin-left:var(--sidebar-width);min-height:100vh;display:flex;flex-direction:column}
.page-content{flex:1;padding:2rem 2.5rem 3rem;max-width:1200px}
.page-content.full{max-width:100%}
/* ===== FRAME VIEW (框景) ===== */
.frame-view{position:relative;padding:2px;border-radius:var(--radius-lg);background:var(--gradient-primary);box-shadow:var(--shadow-lg)}
.frame-view-inner{background:var(--bg-light);border-radius:calc(var(--radius-lg) - 2px);padding:2.5rem 3rem;position:relative;min-height:320px;display:flex;flex-direction:column;justify-content:center}
.frame-view::after{content:'';position:absolute;inset:0;border-radius:var(--radius-lg);box-shadow:inset 0 0 0 1px rgba(255,255,255,0.3);pointer-events:none}
/* ===== SECTION NUMBER ===== */
.section-number{font-family:var(--font-heading);font-size:4.5rem;font-weight:800;line-height:1;color:var(--accent-orange);opacity:0.25;margin-bottom:-0.6rem;user-select:none}
.section-title{font-family:var(--font-heading);font-size:1.8rem;font-weight:800;text-transform:uppercase;letter-spacing:0.02em;color:var(--text-dark);margin-bottom:0.8rem}
.section-subtitle{font-size:1rem;color:rgba(26,26,46,0.6);margin-bottom:1.5rem}
/* ===== GLASS CARD ===== */
.glass-card{background:var(--surface-glass);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid rgba(255,255,255,0.5);border-radius:var(--radius-md);padding:1.8rem;box-shadow:var(--shadow-sm);transition:box-shadow var(--transition-med),transform var(--transition-med)}
.glass-card:hover{box-shadow:var(--shadow-md);transform:translateY(-2px)}
/* ===== REVEAL ANIMATION ===== */
[data-reveal]{opacity:0;transform:translateY(24px);transition:opacity var(--transition-slow),transform var(--transition-slow)}
[data-reveal].revealed{opacity:1;transform:translateY(0)}
[data-reveal][data-reveal-delay="100"]{transition-delay:0.1s}
[data-reveal][data-reveal-delay="200"]{transition-delay:0.2s}
[data-reveal][data-reveal-delay="300"]{transition-delay:0.3s}
/* ===== RESPONSIVE ===== */
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}[data-reveal]{opacity:1;transform:none;transition:none}[data-reveal].revealed{opacity:1;transform:none}.btn:hover,.btn:focus-visible,.glass-card:hover,.glass-card:focus-visible{transform:none}}
@media (max-width:1024px){.footer-grid{grid-template-columns:1fr 1fr;gap:1.5rem}.page-content{padding:1.8rem 1.5rem 2.5rem}.frame-view-inner{padding:2rem 1.5rem}}
@media (max-width:768px){.site-header{width:100%;height:var(--topbar-height);flex-direction:row;align-items:center;box-shadow:0 2px 16px rgba(0,0,0,0.12)}.header-topbar{display:flex}.header-sidebar{position:fixed;top:0;left:0;width:280px;height:100vh;background:var(--primary-blue);transform:translateX(-100%);transition:transform var(--transition-med);z-index:1002;box-shadow:4px 0 24px rgba(0,0,0,0.25)}.header-sidebar[data-open]{transform:translateX(0)}.sidebar-overlay{display:block;position:fixed;inset:0;background:rgba(0,0,0,0.40);z-index:-1;opacity:0;pointer-events:none;transition:opacity var(--transition-med)}.header-sidebar[data-open] .sidebar-overlay{opacity:1;pointer-events:auto}.sidebar-header{padding:1.8rem 1.5rem 1rem}.sidebar-nav{padding:1rem 0}.nav-item{padding:0 0.8rem}.nav-link{padding:0.6rem 0.8rem}.sidebar-footer{padding:1rem 1.5rem 1.5rem}.site-footer{margin-left:0}.footer-grid{grid-template-columns:1fr;gap:1.5rem}.footer-brand-col{order:0}.footer-nav-col{order:1}.footer-contact-col{order:2}.footer-address-col{order:3}.footer-bottom{gap:0.8rem}.footer-meta{flex-direction:column;align-items:center;gap:0.4rem}.page-wrapper{margin-left:0}.page-content{padding:1.5rem 1.2rem 2rem}.section-number{font-size:3rem}.section-title{font-size:1.4rem}.frame-view-inner{padding:1.5rem 1.2rem}.sidebar-locale{text-align:center}}
@media (max-width:480px){.header-logo{font-size:1.05rem}.btn{padding:0.6rem 1.2rem;font-size:0.85rem}.frame-view-inner{padding:1.2rem 1rem}.section-title{font-size:1.2rem}.footer-inner{padding:1.8rem 1rem 1.2rem}}
/* ===== ACCESSIBILITY ===== */
@media (prefers-contrast:high){.nav-link{color:var(--text-light)}.nav-link[aria-current="page"]{color:var(--accent-orange);background:rgba(232,98,46,0.25)}.glass-card{background:rgba(255,255,255,0.9);border-color:var(--border-subtle)}}
/* ===== UTILITY ===== */
.text-gradient{background:var(--gradient-primary);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.text-center{text-align:center}
.mt-1{margin-top:0.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mt-4{margin-top:2rem}.mb-1{margin-bottom:0.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}.mb-4{margin-bottom:2rem}