/* ===== 从一教育官网 · 公共样式 v2.0 ===== */

/* === CSS变量与主题 === */
:root {
    --blue-50: #eff6ff; --blue-100: #dbeafe; --blue-200: #bfdbfe;
    --blue-300: #93c5fd; --blue-400: #60a5fa; --blue-500: #3b82f6;
    --blue-600: #2563eb; --blue-700: #1d4ed8; --blue-800: #1e40af; --blue-900: #1e3a8a;
    --cyan-400: #22d3ee;
    --primary: #0c1929; --text-dark: #1e293b; --text-body: #475569;
    --text-muted: #94a3b8; --white: #ffffff;
    --border: rgba(59,130,246,0.12); --shadow: rgba(59,130,246,0.15);
}

[data-theme="green"] {
    --blue-50: #f0fdf4; --blue-100: #dcfce7; --blue-200: #bbf7d0;
    --blue-300: #86efac; --blue-400: #4ade80; --blue-500: #22c55e;
    --blue-600: #16a34a; --blue-700: #15803d; --blue-800: #166534; --blue-900: #14532d;
    --cyan-400: #34d399; --primary: #0c2918; --text-dark: #1e293b;
    --text-body: #475569; --text-muted: #94a3b8; --white: #ffffff;
    --border: rgba(34,197,94,0.12); --shadow: rgba(34,197,94,0.15);
}

[data-theme="amber"] {
    --blue-50: #fffbeb; --blue-100: #fef3c7; --blue-200: #fde68a;
    --blue-300: #fcd34d; --blue-400: #fbbf24; --blue-500: #f59e0b;
    --blue-600: #d97706; --blue-700: #b45309; --blue-800: #92400e; --blue-900: #78350f;
    --cyan-400: #fb923c; --primary: #291a04; --text-dark: #1e293b;
    --text-body: #475569; --text-muted: #94a3b8; --white: #ffffff;
    --border: rgba(245,158,11,0.12); --shadow: rgba(245,158,11,0.15);
}

[data-theme="rose"] {
    --blue-50: #fff1f2; --blue-100: #ffe4e6; --blue-200: #fecdd3;
    --blue-300: #fda4af; --blue-400: #fb7185; --blue-500: #f43f5e;
    --blue-600: #e11d48; --blue-700: #be123c; --blue-800: #9f1239; --blue-900: #881337;
    --cyan-400: #fb7185; --primary: #290c16; --text-dark: #1e293b;
    --text-body: #475569; --text-muted: #94a3b8; --white: #ffffff;
    --border: rgba(244,63,94,0.12); --shadow: rgba(244,63,94,0.15);
}

[data-theme="dark"] {
    --blue-50: #1a1025; --blue-100: #2d1b3d; --blue-200: #4a2d5e;
    --blue-300: #7c4daa; --blue-400: #a855f7; --blue-500: #8b5cf6;
    --blue-600: #7c3aed; --blue-700: #6d28d9; --blue-800: #5b21b6; --blue-900: #4c1d95;
    --cyan-400: #c084fc; --primary: #0a0612; --text-dark: #e2e8f0;
    --text-body: #a5b4c7; --text-muted: #64748b; --white: #14101f;
    --border: rgba(139,92,246,0.15); --shadow: rgba(139,92,246,0.2);
}

/* === 主题切换器 === */
.theme-switcher{position:fixed;bottom:24px;left:24px;z-index:999;display:flex;flex-direction:column;gap:8px;align-items:flex-start}
.theme-btn{width:36px;height:36px;border-radius:50%;border:2.5px solid rgba(255,255,255,.85);cursor:pointer;transition:all .3s;box-shadow:0 2px 10px rgba(0,0,0,.15);flex-shrink:0}
.theme-btn:hover{transform:scale(1.15);box-shadow:0 4px 16px rgba(0,0,0,.25)}
.theme-btn.active{border-color:var(--blue-500);box-shadow:0 0 0 3px var(--shadow)}
.theme-btn[data-t="blue"]{background:linear-gradient(135deg,#3b82f6,#1d4ed8)}
.theme-btn[data-t="green"]{background:linear-gradient(135deg,#22c55e,#15803d)}
.theme-btn[data-t="amber"]{background:linear-gradient(135deg,#f59e0b,#b45309)}
.theme-btn[data-t="rose"]{background:linear-gradient(135deg,#f43f5e,#be123c)}
.theme-btn[data-t="dark"]{background:linear-gradient(135deg,#8b5cf6,#4c1d95)}

/* === 基础重置 === */
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:'Noto Sans SC',-apple-system,sans-serif;background:var(--white);color:var(--text-dark);line-height:1.7;overflow-x:hidden}

/* === 导航栏 === */
.nav{position:fixed;top:0;left:0;right:0;z-index:1000;padding:0 5%;display:flex;justify-content:space-between;align-items:center;height:64px;background:rgba(255,255,255,0.95);backdrop-filter:blur(20px);border-bottom:1px solid var(--border);transition:all .3s}
.nav.scrolled{height:56px;box-shadow:0 2px 20px rgba(0,0,0,.06)}
.nav-brand{display:flex;align-items:center;gap:10px;text-decoration:none}
.nav-logo{width:38px;height:38px;background:linear-gradient(135deg,var(--blue-500),var(--blue-700));border-radius:9px;display:flex;align-items:center;justify-content:center;color:#fff;font-weight:900;font-size:1.1rem}
.nav-name{font-size:1.15rem;font-weight:700;color:var(--blue-800);letter-spacing:1px}
.nav-name b{color:var(--blue-500);font-weight:700}
.nav-menu{display:flex;gap:2rem;list-style:none}
.nav-menu a{color:var(--text-body);text-decoration:none;font-size:.88rem;font-weight:500;position:relative;transition:color .3s}
.nav-menu a:hover{color:var(--blue-600)}
.nav-menu a::after{content:'';position:absolute;bottom:-4px;left:0;width:0;height:2px;background:var(--blue-500);transition:width .3s}
.nav-menu a:hover::after{width:100%}
.nav-btn{padding:.55rem 1.3rem;background:linear-gradient(135deg,var(--blue-500),var(--blue-700));color:#fff;border:none;border-radius:8px;font-weight:600;font-size:.82rem;cursor:pointer;text-decoration:none;display:inline-block;transition:all .3s;box-shadow:0 3px 12px var(--shadow)}
.nav-btn:hover{transform:translateY(-1px);box-shadow:0 6px 20px var(--shadow)}
.mobile-menu-btn{display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text-dark);padding:4px}

/* === 公共区块 === */
.sec{position:relative;z-index:1;padding:5.5rem 5%}
.sec-head{text-align:center;max-width:660px;margin:0 auto 3rem}
.sec-tag{display:inline-block;padding:.25rem .85rem;background:var(--blue-50);border:1px solid var(--blue-200);border-radius:50px;font-size:.78rem;color:var(--blue-600);margin-bottom:.6rem;letter-spacing:1px}
.sec-head h2{font-size:clamp(1.7rem,3.2vw,2.5rem);font-weight:800;color:var(--text-dark);margin-bottom:.6rem}
.sec-head p{color:var(--text-body);font-size:1rem}

/* === 按钮 === */
.btn-main{padding:.8rem 1.8rem;background:linear-gradient(135deg,var(--blue-500),var(--blue-700));color:#fff;border:none;border-radius:10px;font-weight:700;font-size:.92rem;cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;gap:6px;transition:all .3s;box-shadow:0 6px 20px var(--shadow)}
.btn-main:hover{transform:translateY(-2px);box-shadow:0 10px 30px rgba(59,130,246,.35)}
.btn-ghost{padding:.8rem 1.8rem;background:0;color:var(--blue-200);border:1.5px solid rgba(96,165,250,.35);border-radius:10px;font-weight:600;font-size:.92rem;cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;gap:6px;transition:all .3s}
.btn-ghost:hover{border-color:var(--blue-400);color:#fff;background:rgba(96,165,250,.08)}

/* === 页脚 === */
footer{border-top:1px solid var(--blue-100);padding:2.5rem 5%;background:var(--blue-50)}
.foot{max-width:1360px;margin:0 auto;display:grid;grid-template-columns:2fr 1fr 1fr 1fr;gap:2.5rem}
.foot-brand .nav-brand{margin-bottom:.6rem}
.foot-brand>p{color:var(--text-body);font-size:.84rem;max-width:280px;line-height:1.7}
.foot h4{font-size:.88rem;font-weight:700;margin-bottom:.7rem;color:var(--text-dark)}
.foot ul{list-style:none}
.foot li{margin-bottom:.4rem}
.foot li a{color:var(--text-body);text-decoration:none;font-size:.82rem;transition:color .3s}
.foot li a:hover{color:var(--blue-600)}
.foot-copy{max-width:1360px;margin:1.5rem auto 0;padding-top:1.2rem;border-top:1px solid var(--blue-200);text-align:center;color:var(--text-muted);font-size:.76rem}

/* === 动画 === */
@keyframes fadeUp{from{opacity:0;transform:translateY(30px)}to{opacity:1;transform:translateY(0)}}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.4}}
.rv{opacity:0;transform:translateY(35px);transition:all .7s ease}
.rv.on{opacity:1;transform:translateY(0)}


/* === 子页面 Banner === */
.page-banner{position:relative;overflow:hidden;background:linear-gradient(160deg, #0c1929 0%, #0f2847 40%, #1e3a8a 100%);padding:8rem 5% 4rem}

[data-theme="green"] .page-banner{background:linear-gradient(160deg, #052e16 0%, #064e3b 40%, #14532d 100%)}
[data-theme="amber"] .page-banner{background:linear-gradient(160deg, #291a04 0%, #451a03 40%, #78350f 100%)}
[data-theme="rose"] .page-banner{background:linear-gradient(160deg, #290c16 0%, #4c0519 40%, #881337 100%)}
[data-theme="dark"] .page-banner{background:linear-gradient(160deg, #0a0612 0%, #1e1033 40%, #4c1d95 100%)}

.page-banner-inner{position:relative;z-index:2;max-width:1360px;margin:0 auto;text-align:center}
.page-banner-tag{display:inline-flex;align-items:center;gap:6px;padding:.35rem .9rem;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.15);border-radius:50px;font-size:.78rem;color:rgba(255,255,255,.7);margin-bottom:1.2rem}
.page-banner h1{font-size:clamp(2rem,4vw,3rem);font-weight:900;color:#fff;line-height:1.25;margin-bottom:.8rem}
.page-banner h1 em{font-style:normal;background:linear-gradient(135deg,var(--blue-300),var(--cyan-400));-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
.page-banner p{font-size:1.05rem;color:rgba(255,255,255,.75);max-width:620px;margin:0 auto;line-height:1.8}
.page-banner-stats{display:flex;justify-content:center;gap:2.5rem;margin-top:2rem;flex-wrap:wrap}
.page-banner-stats .stat{text-align:center}
.page-banner-stats .num{font-size:1.8rem;font-weight:900;color:#fff;display:block}
.page-banner-stats .lbl{font-size:.78rem;color:rgba(255,255,255,.6);margin-top:.2rem;display:block}

/* === 响应式 === */
@media(max-width:1024px){
    .foot{grid-template-columns:1fr 1fr}
    .page-banner{padding:7rem 5% 3rem}
}
@media(max-width:768px){
    .mobile-menu-btn{display:block}
    .nav-menu.active{display:flex;flex-direction:column;position:absolute;top:64px;left:0;right:0;background:rgba(255,255,255,0.98);backdrop-filter:blur(20px);padding:1.5rem 5%;gap:1.2rem;border-bottom:1px solid var(--border);box-shadow:0 8px 30px rgba(0,0,0,.08)}
    .nav-menu.active a{font-size:1rem}
    .nav-menu{display:none}
    .sec{padding:3.5rem 5%}
    .page-banner-stats{flex-direction:column;gap:1rem}
    .foot{grid-template-columns:1fr;gap:1.5rem}
}