/* =========================================================
   Renova 榮啟新能源 — Shared Site Framework
   Common chrome: tokens, header/nav, mobile menu, buttons,
   section header, CTA, footer, reveal & toast.
   Page-specific styles live in each page's <style> block.
   ========================================================= */

:root {
    --blue-900: #001a33;
    --blue-800: #00264d;
    --blue-700: #003366;
    --blue-600: #004080;
    --blue-500: #004899;
    --blue-400: #0066aa;
    --teal-500: #009999;
    --teal-400: #00b3b3;
    --teal-300: #33cccc;
    --teal-200: #66e0e0;
    --teal-100: #b3f0f0;
    --gray-50: #f7f9fb;
    --gray-100: #eef2f6;
    --gray-200: #dde3ea;
    --gray-500: #6b7d8e;
    --gray-700: #3a4a5a;
    --gray-900: #121926;
    --white: #ffffff;
    --accent-gold: #c8a84e;
    --radius-2xl: 2rem;
    --radius-xl: 1.25rem;
    --radius-lg: 1rem;
    --radius-sm: 0.5rem;
    --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
    --ease-out-quart: cubic-bezier(0.25, 1, 0.5, 1);
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 90px; font-size: 16px; }

body {
    font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    color: var(--gray-700);
    background: var(--white);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, .display { font-family: 'Outfit', 'Noto Sans SC', sans-serif; }

a { color: inherit; }

::selection { background: rgba(0,179,179,0.22); }

::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--gray-100); }
::-webkit-scrollbar-thumb { background: var(--blue-500); border-radius: 3px; }

.container { width: 100%; max-width: 1280px; margin: 0 auto; padding: 0 clamp(1.25rem, 4vw, 3rem); }

.section { padding: clamp(4rem, 8vw, 7rem) 0; }
.section--alt { background: var(--gray-50); }

/* ===== HEADER / NAV ===== */
.header {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    height: 76px;
    transition: all 0.4s var(--ease-out-expo);
}
.header.is-scrolled {
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(24px) saturate(180%);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    box-shadow: 0 1px 0 rgba(0,0,0,0.05), 0 4px 24px rgba(0,0,0,0.06);
}
.header-inner {
    display: flex; align-items: center; justify-content: space-between;
    height: 100%; max-width: 1400px; margin: 0 auto;
    padding: 0 clamp(1.25rem, 4vw, 3rem);
}
.logo-link { display: flex; align-items: center; gap: 0.75rem; text-decoration: none; }
.logo-link img { height: 52px; width: auto; transition: filter 0.3s ease; }
.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-cn { font-size: 1.0625rem; font-weight: 700; letter-spacing: -0.01em; color: var(--blue-900); font-family: 'Noto Sans SC', sans-serif; }
.brand-en { font-size: 0.6875rem; font-weight: 500; letter-spacing: 0.03em; color: var(--gray-500); }
.header:not(.is-scrolled) .logo-link img { filter: brightness(0) invert(1); }
.header:not(.is-scrolled) .brand-cn { color: var(--white); }
.header:not(.is-scrolled) .brand-en { color: rgba(255,255,255,0.7); }
.header.is-scrolled .logo-link img { filter: none; }

.nav-links { display: none; align-items: center; gap: 2px; }
@media (min-width: 1100px) { .nav-links { display: flex; } }
.nav-links a {
    text-decoration: none; color: var(--gray-700); font-size: 0.875rem;
    font-weight: 500; padding: 0.5rem 0.875rem; border-radius: 9999px;
    transition: all 0.2s var(--ease-out-expo); white-space: nowrap;
}
.nav-links a:hover { color: var(--blue-500); background: rgba(0,72,153,0.06); }
.nav-links a.active { color: var(--blue-500); background: rgba(0,72,153,0.08); font-weight: 600; }

/* Dropdown */
.nav-dropdown { position: relative; }
.nav-trigger { cursor: default; display: inline-flex; align-items: center; }
.nav-trigger::after {
    content: ''; width: 0; height: 0; margin-left: 0.3rem;
    border-left: 4px solid transparent; border-right: 4px solid transparent;
    border-top: 5px solid currentColor; opacity: 0.55;
    transition: transform 0.25s var(--ease-out-expo);
}
.nav-dropdown:hover .nav-trigger::after,
.nav-dropdown:focus-within .nav-trigger::after { transform: rotate(180deg); }
.nav-submenu {
    position: absolute; top: calc(100% + 10px); left: 50%;
    transform: translateX(-50%) translateY(8px);
    min-width: 250px; background: var(--white);
    border-radius: 14px; padding: 0.5rem;
    box-shadow: 0 18px 50px rgba(0,26,51,0.18);
    border: 1px solid rgba(0,72,153,0.08);
    opacity: 0; visibility: hidden; z-index: 1000;
    transition: all 0.25s var(--ease-out-expo);
}
.nav-submenu::before { content: ''; position: absolute; bottom: 100%; left: 0; right: 0; height: 12px; }
.nav-dropdown:hover .nav-submenu,
.nav-dropdown:focus-within .nav-submenu { opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0); }
.nav-links .nav-submenu a { display: block; padding: 0.625rem 0.875rem; border-radius: 10px; font-size: 0.875rem; }
.nav-links .nav-submenu a:hover { background: rgba(0,72,153,0.06); }
.nav-links .nav-submenu .sub-t { font-weight: 600; color: var(--blue-900); }
.header:not(.is-scrolled) .nav-links a { color: rgba(255,255,255,0.92); }
.header:not(.is-scrolled) .nav-links a:hover { color: var(--white); background: rgba(255,255,255,0.12); }
.header:not(.is-scrolled) .nav-links a.active { color: var(--white); background: rgba(255,255,255,0.14); }

.btn-cta {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.625rem 1.5rem;
    background: linear-gradient(135deg, var(--blue-500), var(--teal-500));
    color: #ffffff !important; font-size: 0.875rem; font-weight: 600;
    border-radius: 9999px; border: none; cursor: pointer; text-decoration: none;
    transition: all 0.3s var(--ease-out-expo);
    box-shadow: 0 2px 12px rgba(0,72,153,0.3);
    white-space: nowrap;
}
.btn-cta:hover { transform: translateY(-1px); box-shadow: 0 6px 24px rgba(0,72,153,0.4); }

.menu-toggle {
    display: flex; flex-direction: column; gap: 5px;
    background: none; border: none; cursor: pointer; padding: 8px; z-index: 1001;
}
@media (min-width: 1100px) { .menu-toggle { display: none; } }
.menu-toggle span {
    display: block; width: 22px; height: 2px; background: var(--blue-500);
    border-radius: 2px; transition: all 0.3s var(--ease-out-expo);
}
.menu-toggle.is-active span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
.menu-toggle.is-active span:nth-child(2) { opacity: 0; }
.menu-toggle.is-active span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }
.header:not(.is-scrolled) .menu-toggle span { background: var(--white); }
@media (max-width: 480px) { .brand-en { display: none; } .brand-cn { font-size: 0.9375rem; } }

.mobile-menu {
    position: fixed; top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(255,255,255,0.98); backdrop-filter: blur(30px);
    z-index: 999; display: flex; flex-direction: column; justify-content: center;
    padding: 2rem; opacity: 0; pointer-events: none;
    transition: opacity 0.4s var(--ease-out-expo);
}
.mobile-menu.is-open { opacity: 1; pointer-events: auto; }
.mobile-menu a {
    display: block; padding: 1rem 0; font-size: 1.25rem; font-weight: 600;
    color: var(--gray-700); text-decoration: none; border-bottom: 1px solid var(--gray-100);
}
.mobile-menu a:hover { color: var(--blue-500); }
.mobile-sub-wrap { padding: 0.5rem 0; border-bottom: 1px solid var(--gray-100); }
.mobile-sub-title { font-size: 0.8rem; font-weight: 700; letter-spacing: 0.12em; color: var(--gray-500); text-transform: uppercase; padding: 0.5rem 0 0.25rem; }
.mobile-sub a { font-size: 1.05rem; font-weight: 500; padding: 0.65rem 0 0.65rem 1rem; border-bottom: none; }
.mobile-menu a.active { color: var(--blue-500); }

/* ===== SECTION HEADER ===== */
.section-header { text-align: center; margin-bottom: 4rem; }
.section-label {
    display: inline-flex; align-items: center; gap: 0.625rem;
    font-family: 'Outfit', sans-serif;
    font-size: 0.7rem; font-weight: 600; letter-spacing: 0.22em;
    color: var(--blue-500); text-transform: uppercase;
    margin-bottom: 1rem; padding: 0.5rem 1.5rem;
    background: linear-gradient(135deg, rgba(0,72,153,0.05), rgba(0,179,179,0.06));
    border: 1px solid rgba(0,72,153,0.1);
    border-radius: 9999px;
    position: relative;
}
.section-label::before {
    content: ''; width: 6px; height: 6px;
    background: linear-gradient(135deg, var(--blue-500), var(--teal-500));
    border-radius: 50%; flex-shrink: 0;
}
.section-header h2 {
    font-size: clamp(1.75rem, 4vw, 2.75rem);
    font-weight: 800; color: var(--blue-900); line-height: 1.2;
    margin-bottom: 0.75rem; letter-spacing: -0.02em;
}
.section-header p { color: var(--gray-500); font-size: 1.0625rem; max-width: 480px; margin: 0 auto; }

/* ===== CTA ===== */
.cta-section {
    position: relative; overflow: hidden;
    background: linear-gradient(135deg, var(--blue-900) 0%, var(--blue-700) 45%, var(--teal-500) 130%);
    color: #fff; padding: clamp(4rem, 8vw, 6.5rem) 0; text-align: center;
}
.cta-section::before {
    content: ''; position: absolute; inset: 0;
    background:
        radial-gradient(circle at 18% 20%, rgba(255,255,255,0.10), transparent 42%),
        radial-gradient(circle at 82% 78%, rgba(0,179,179,0.22), transparent 46%);
}
.cta-inner { position: relative; z-index: 1; max-width: 720px; margin: 0 auto; padding: 0 1.5rem; }
.cta-label {
    display: inline-block; font-family: 'Outfit', sans-serif; font-size: 0.72rem; font-weight: 600;
    letter-spacing: 0.24em; text-transform: uppercase; color: var(--teal-200);
    padding: 0.4rem 1.25rem; border: 1px solid rgba(255,255,255,0.22); border-radius: 9999px; margin-bottom: 1.5rem;
}
.cta-section h2 { font-size: clamp(2rem, 5vw, 3rem); font-weight: 800; color: #fff; margin-bottom: 1rem; letter-spacing: -0.02em; }
.cta-section h2 em { font-style: normal; background: linear-gradient(120deg, #fff, var(--teal-200)); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.cta-desc { color: rgba(255,255,255,0.82); font-size: 1.0625rem; margin-bottom: 2rem; }
.cta-buttons { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
.cta-btn-primary {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.95rem 2rem; background: #fff; color: var(--blue-700);
    font-weight: 700; font-size: 0.975rem; border-radius: 9999px; text-decoration: none;
    transition: all 0.3s var(--ease-out-expo); box-shadow: 0 10px 30px rgba(0,0,0,0.18);
}
.cta-btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 40px rgba(0,0,0,0.28); }
.cta-btn-secondary {
    display: inline-flex; align-items: center; gap: 0.5rem;
    padding: 0.95rem 2rem; background: rgba(255,255,255,0.08); color: #fff;
    font-weight: 600; font-size: 0.975rem; border-radius: 9999px; text-decoration: none;
    border: 1px solid rgba(255,255,255,0.28); transition: all 0.3s var(--ease-out-expo);
}
.cta-btn-secondary:hover { background: rgba(255,255,255,0.16); transform: translateY(-2px); }

/* ===== FOOTER ===== */
.footer { background: var(--blue-900); color: #8a9bb0; padding: 4rem 0 0; }
.footer .container { } /* spacing handled below */
.footer-grid { display: grid; grid-template-columns: 1fr; gap: 2.5rem; padding-bottom: 3rem; }
@media (min-width: 768px) { .footer-grid { grid-template-columns: 2fr 1fr 1fr 1fr; gap: 3rem; } }
.footer-brand img { height: 44px; margin-bottom: 1rem; }
.footer-brand h4 { color: #fff; font-size: 1.125rem; margin-bottom: 0.75rem; font-weight: 700; }
.footer-brand p { font-size: 0.875rem; line-height: 1.7; }
.footer-col h5 { color: #fff; font-size: 0.95rem; margin-bottom: 1.1rem; font-weight: 600; }
.footer-col a { display: block; color: #8a9bb0; text-decoration: none; font-size: 0.875rem; padding: 0.4rem 0; transition: color 0.2s; }
.footer-col a:hover { color: var(--teal-400); }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.08); padding: 1.5rem 0;
    font-size: 0.8125rem; color: #6c7f93; text-align: center;
}
.footer-bottom a { color: inherit; text-decoration: none; margin: 0 0.5rem; }
.footer-bottom a:hover { color: var(--teal-400); }

/* ===== REVEAL & TOAST ===== */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity 0.7s var(--ease-out-expo), transform 0.7s var(--ease-out-expo); }
.reveal.is-visible { opacity: 1; transform: translateY(0); }
.reveal-d1 { transition-delay: 0.1s; }
.reveal-d2 { transition-delay: 0.2s; }
.reveal-d3 { transition-delay: 0.3s; }
.toast {
    position: fixed; left: 50%; bottom: 2rem; transform: translateX(-50%) translateY(1.5rem);
    background: var(--blue-900); color: #fff; padding: 0.85rem 1.5rem; border-radius: 9999px;
    font-size: 0.9rem; box-shadow: 0 12px 36px rgba(0,0,0,0.3); z-index: 2000;
    opacity: 0; pointer-events: none; transition: all 0.4s var(--ease-out-expo);
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

@media (prefers-reduced-motion: reduce) {
    .reveal, .stagger > * { opacity: 1 !important; transform: none !important; transition: none !important; }
    html { scroll-behavior: auto; }
}