/* --- Global Variables --- */
:root {
    --bg-color: #ffffff;
    --text-main: #333333;
    --text-secondary: #666666;
    --accent-color: #D3610B;
    /* Keep orange accent or change to #0056b3 for blue */
    --accent-light: #fdf0e6;
    --border-color: #e0e0e0;
    --card-bg: #ffffff;
    --card-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);

    /* Layout */
    --site-width: 75vw;
    /* Standardized width */
    --site-padding: 20px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s;
}

a:hover {
    color: var(--accent-color);
}

.container {
    max-width: var(--site-width);
    margin: 0 auto;
    position: relative;
}

.site-footer .container {
    max-width: 67.708vw;
}

/* --- Header --- */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

header.scrolled {
    background: #f2f6fb;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.header-wrapper {
    max-width: var(--site-width);
    margin: 0 auto;
}

.nav-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-links-left,
.nav-links-right {
    display: flex;
    gap: 12.76vw;
    font-weight: bold;
    font-size: 1.042vw;
    color: #454545;
    flex: 1;
}

.nav-links-right {
    justify-content: flex-end;
}

.logo {
    flex: 0 0 auto;
    display: flex;
    align-items: center;
}

.logo img {
    height: 5.208vw;
    width: 10.885vw;
}

/* --- Hero / Banner --- */
.hero-section {
    position: relative;
    width: 100vw;
    height: 45vw;
    display: flex;
    align-items: center;
    background: url('img/hero_bg.webp') no-repeat center center;
    background-size: cover;
    overflow: hidden;
}

.hero-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    position: relative;
    z-index: 2;
}

.hero-content-left {
    flex: 1;
    max-width: 50%;
    z-index: 2;
}

.hero-title {
    font-size: 4.688vw;
    line-height: 5.208vw;
    font-weight: bold;
    color: #0080FA;
    letter-spacing: 0.05em;
    margin-bottom: 1.5vw;
}

.hero-description {
    font-size: 1.458vw;
    color: #777777;
    font-weight: 400;
    line-height: 2.344vw;
    letter-spacing: 0.05em;
    margin-bottom: 2.5vw;
}

.hero-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 10.104vw;
    height: 2.396vw;
    background: linear-gradient(to right, #0376E6, #01A0F4);
    color: white;
    border-radius: 2.083vw;
    font-size: 1.25vw;
    line-height: 64px;
    letter-spacing: 0.05em;
    font-weight: 500;
    transition: all 0.3s ease;
}

.hero-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(3, 118, 230, 0.4);
    color: white;
}

.hero-bottom-bg {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    pointer-events: none;
}

.hero-bottom-bg img {
    width: 100%;
    height: auto;
    display: block;
}

/* --- Sections Common --- */
/* --- Features --- */
.features-section {
    padding: 3.125vw 0 8.333vw 0;
    background: #ffffff;
}

.features-section .section-title {
    text-align: center;
    font-size: 2.5vw;
    color: #000000;
    font-weight: bold;
    margin-bottom: 0.833vw;
    margin-top: 0;
}

.features-section .section-subtitle {
    text-align: center;
    font-size: 1.458vw;
    color: #777777;
    font-weight: 500;
    margin-bottom: 3.125vw;
    letter-spacing: 0.3em;
}

.features-list {
    max-width: var(--site-width);
    margin: 0 auto;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 4vw;
    margin-bottom: 5.208vw;
}

.feature-item:last-child {
    margin-bottom: 0;
}

/* Image on Right */
.feature-item.feature-right {
    flex-direction: row;
}

/* Image on Left */
.feature-item.feature-left {
    flex-direction: row;
}

.feature-content {
    flex: 1;
    max-width: 31.458vw;
}

.feature-number {
    font-size: 1.875vw;
    font-weight: bold;
    margin-bottom: 1.042vw;
    background: linear-gradient(to right, #037BE8, #019CF3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-title {
    font-size: 1.875vw;
    font-weight: bold;
    background: linear-gradient(to right, #037BE8, #019CF3);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.521vw;
}

.feature-subtitle {
    font-size: 1.875vw;
    color: #000000;
    margin-bottom: 1.563vw;
    font-weight: bold;
}

.feature-points {
    list-style: none;
    padding: 0;
    margin: 0;
}

.feature-points li {
    position: relative;
    padding-left: 1vw;
    margin-bottom: 1.563vw;
    font-size: 1.042vw;
    color: #777777;
    font-weight: 500;
    line-height: 1.8;
}

.feature-points li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #777777;
}

.feature-image {
    flex: 1;
    max-width: 32.135vw;
    height: 22.708vw;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-image img {
    width: 100%;
    height: auto;
    border-radius: 2.135vw;
}

/* --- About Section --- */
.about-section {
    width: 100vw;
    padding: 3.125vw 0;
    background: url('img/about_bg.webp') no-repeat center center;
    background-size: cover;
    text-align: center;
}

.about-tag {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 10.104vw;
    height: 2.396vw;
    background: linear-gradient(to right, #0376E6, #01A0F4);
    color: white;
    border-radius: 5.208vw;
    font-size: 1.25vw;
    line-height: 64px;
    letter-spacing: 0.05em;
    font-weight: 500;
    margin-bottom: 3.073vw;
}

.about-title {
    font-size: 2.5vw;
    font-weight: bold;
    color: #000000;
    line-height: 1.5;
    margin-bottom: 2.865vw;
}

.about-description {
    font-size: 1.25vw;
    color: #777777;
    line-height: 2;
    letter-spacing: 0.05em;
}

/* --- Core Functions Section --- */
.core-functions-section {
    width: 100vw;
    /* 66px top padding, bottom padding to separate from next section */
    padding: 3.438vw 0 6.25vw 0;
    background: #f3f8fe;
    position: relative;
    overflow: hidden;
}

.core-header {
    display: flex;
    justify-content: flex-start;
    /* Aligned to left in design Frame 359 but centered in overall layout usually. Design shows '功能' tag. */
    /* Looking at the design screenshot, the tag seems to be part of the flow. Frame 359 has padding-left 254px/239px. */
    /* But we are using a container. Let's center it or align as per previous 'Audience' section style which had a centered tag. */
    /* The design Frame 359 shows "text" (功能) at top left relative to the content group. */
    /* Let's center it for consistency with Audience section unless specified otherwise. The user said "implement this part", likely referring to the whole block. */
    justify-content: center;
    margin-bottom: 7.5vw;
    /* Space between tag and items, approx 144px */
}

.core-tag {
    position: relative;
    width: 9.271vw;
    /* 178px */
    height: 2.708vw;
    /* 52px */
    background: #ffffff;
    /* Assuming white pill background like Audience */
    /* Actually Frame 359 shows a rectangle225 (image?) or just text. */
    /* But the user prompt says "功能" text. Let's reuse the pill style from Audience for consistency. */
    /* Wait, the design CSS shows .rectangle225 as absolute. */
    /* Let's use the Audience pill style: */
    border-radius: 1.354vw;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 0.208vw 0.521vw rgba(0, 0, 0, 0.05);
}

/* Reuse .tag-text from Audience section if possible, or duplicate styles */
.core-tag .tag-text {
    font-size: 1.25vw;
    font-weight: 700;
    color: #0288ec;
    letter-spacing: 0.125vw;
    font-family: OPPOSans, "PingFang SC", "Microsoft YaHei", sans-serif;
}

.core-grid {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    width: 100%;
}

.core-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 13.906vw;
    /* Approx 267px */
    text-align: center;
}

.core-image-wrapper {
    position: relative;
    width: 13.906vw;
    /* 267px */
    height: 12.656vw;
    /* 243px */
    margin-bottom: 0.833vw;
    /* Space between image and text */
    display: flex;
    justify-content: center;
    align-items: center;
}

.core-blur-bg {
    position: absolute;
    top: 1.875vw;
    /* 36px */
    left: 50%;
    transform: translateX(-50%);
    width: 8.854vw;
    /* 170px */
    height: 8.958vw;
    /* 172px */
    border-radius: 50%;
    background: #FFA600;
    filter: blur(6.51vw);
    /* 125px */
    opacity: 0.59;
    z-index: 1;
}

.core-image {
    position: relative;
    width: 100%;
    height: auto;
    z-index: 2;
    object-fit: contain;
}

.core-image:nth-child(1) {
    width: 12.656vw;
    height: 12.656vw;
}

.core-image:nth-child(2) {
    width: 11.198vw;
    height: 11.198vw;
}

.core-image:nth-child(3) {
    width: 11.198vw;
    height: 11.198vw;
}

.core-image:nth-child(4) {
    width: 14.323vw;
    height: 14.323vw;
}

.core-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    z-index: 2;
}

.core-title {
    font-size: 1.875vw;
    /* 36px */
    font-weight: 700;
    color: #000000;
    letter-spacing: 0.188vw;
    /* 3.6px */
    line-height: 2.76vw;
    /* 53px */
    margin-bottom: 0.365vw;
    /* 7px */
    font-family: "HarmonyOS Sans", "PingFang SC", sans-serif;
}

.core-desc {
    font-size: 1.042vw;
    /* 20px */
    font-weight: 500;
    color: #777777;
    letter-spacing: 0.052vw;
    /* 1px */
    line-height: 1.719vw;
    /* 33px */
    width: 11.875vw;
    /* 228px */
    margin: 0;
}



/* --- Audience Section --- */
.audience-section {
    width: 100vw;
    padding: 3.438vw 0 8.802vw 0;
    background: #f3f8fe;
    position: relative;
    overflow: hidden;
}

.audience-header {
    display: flex;
    justify-content: center;
    margin-bottom: 2.552vw;
}

.audience-tag {
    position: relative;
    width: 9.271vw;
    height: 2.708vw;
    background: #ffffff;
    border-radius: 1.354vw;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 0.208vw 0.521vw rgba(0, 0, 0, 0.05);
}

.tag-text {
    font-size: 1.25vw;
    font-weight: 700;
    color: #0288ec;
    letter-spacing: 0.125vw;
    font-family: OPPOSans, "PingFang SC", "Microsoft YaHei", sans-serif;
}

.audience-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    row-gap: 4.427vw;
    width: 100%;
}

.audience-card-wrapper {
    position: relative;
    width: 36.406vw;
    height: 15.641vw;
}

.audience-card-body {
    width: 100%;
    height: 15.625vw;
    /* 300px */
    border-radius: 1.667vw;
    /* 32px */
    background-image: linear-gradient(270deg, #69afff 0%, #1580ff 50%, #4d9fff 100%);
    padding: 1.563vw 1.875vw 1.563vw 2.76vw;
    box-sizing: border-box;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.audience-text-group {
    display: flex;
    flex-direction: column;
}

.audience-card-white-bg {
    width: 17.135vw;
    /* 329px */
    height: 12.5vw;
    /* 240px */
    background: #ffffff;
    border-radius: 1.51vw;
    /* 29px */
    flex-shrink: 0;
    /* Prevent shrinking */
}

.audience-card-title {
    font-size: 1.875vw;
    /* 36px */
    font-weight: 700;
    color: #ffffff;
    letter-spacing: 0.188vw;
    /* 3.6px */
    margin-top: -0.052vw;
    /* -1px */
    margin-bottom: 0;
    line-height: 2.76vw;
    /* 53px */
    font-family: OPPOSans, "PingFang SC", sans-serif;
}

.audience-card-desc {
    font-size: 1.042vw;
    /* 20px */
    font-weight: 500;
    color: #ffffff;
    letter-spacing: 0.052vw;
    /* 1px */
    line-height: 1.719vw;
    /* 33px */
    margin-top: 1.667vw;
    /* 33px */
    width: 11.927vw;
    /* 229px */
}

.audience-card-image {
    position: absolute;
    bottom: 0.6vw;
    right: 1.875vw;
    /* 36px (Matches padding-right of body) */
    width: 17.135vw;
    /* 329px */
    height: 15.938vw;
    /* 306px */
    filter: drop-shadow(0.417vw 0 1.042vw rgba(0, 0, 0, 0.1));
    /* 8px 0 20px */
    overflow: visible;
    z-index: 10;
    display: flex;
    align-items: flex-end;
}

.audience-card-image img {
    width: 100%;
    height: 17.5vw;
    object-fit: cover;
}



/* --- Site Footer --- */
.site-footer {
    background-color: #01153A;
    color: #ffffff;
    padding: 2.813vw 0 3.542vw 0;
    font-size: 0.729vw;
    position: relative;
    overflow: hidden;
}

.site-footer .container {
    display: flex;
    flex-direction: column;
    gap: 2.604vw;
    position: relative;
    z-index: 1;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: 5.208vw;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.footer-logo img {
    width: 11.458vw;
    height: 5.208vw;
}

.footer-link {
    display: flex;
    align-items: center;
    gap: 0.781vw;
    color: #FFFFFF;
    font-size: 0.833vw;
    font-weight: bold;
    line-height: 1.771vw;
    letter-spacing: 0.05em;
}

.footer-link a {
    color: #FFFFFF;
    transition: color 0.3s;
}

.footer-link a:hover {
    color: rgba(255, 255, 255, 0.7);
}

.link-divider {
    color: #FFFFFF;
    font-size: 0.833vw;
    font-weight: bold;
}

.footer-nav h3 {
    font-size: 0.833vw;
    font-weight: bold;
    color: #FFFFFF;
    margin-bottom: 2.031vw;
    position: relative;
}

.footer-contact h3 {
    font-size: 0.833vw;
    font-weight: bold;
    color: #FFFFFF;
    margin-bottom: 2.396vw;
    position: relative;
}

.footer-text {
    font-size: 0.729vw;
    color: #FFFFFF;
    line-height: 1.563vw;
    letter-spacing: 0.05em;
}

.footer-text p {
    margin: 0;
}

.footer-contact .contact-item {
    font-size: 0.729vw;
    color: #FFFFFF;
    line-height: 1.563vw;
    letter-spacing: 0.05em;
}

.footer-contact .contact-item p {
    margin: 0;
}

.contact-email {
    margin-top: 20px;
}

.contact-email a {
    color: #FFFFFF;
}

.contact-email a:hover {
    color: rgba(255, 255, 255, 0.7);
}

.footer-bg {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
}

.footer-bg img {
    max-width: 100%;
    height: auto;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 1);
    padding-top: 30px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 0.521vw;
    color: #FFFFFF;
    font-size: 0.833vw;
    line-height: 105%;
    letter-spacing: 0;
}

.footer-bottom p {
    margin: 0;
}

.footer-bottom a {
    color: #FFFFFF;
}

.footer-bottom a:hover {
    color: rgba(255, 255, 255, 0.7);
}

.footer-policy {
    display: flex;
    align-items: center;
    gap: 0.417vw;
}

.footer-policy .link-divider {
    color: #FFFFFF;
}