/* DeepSeek End-Button Focus Design System - endbutton.css */
:root {
  --bg-pure: #030712;
  --bg-surface: #0b0f19;
  --bg-card: #111827;
  --bg-card-hover: #162032;
  --border-subtle: #1f293d;
  --border-highlight: #38bdf8;
  --text-main: #f9fafb;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;
  --accent-cyan: #0ea5e9;
  --accent-emerald: #10b981;
  --font-serif: "Charter", "Georgia", "Source Serif Pro", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
}

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

html {
  scroll-behavior: smooth;
  background-color: var(--bg-pure);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.7;
}

body {
  background-color: var(--bg-pure);
  color: var(--text-main);
  min-height: 100vh;
  overflow-x: hidden;
}

.container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶栏 Header: Logo、三个导航、主按钮「进入网页版」、汉堡按钮 */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(3, 7, 18, 0.94);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  height: 64px;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand-link {
  display: flex;
  align-items: center;
  text-decoration: none;
}

.logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
}

.brand-text {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.02em;
}

.brand-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 2px 8px;
  background-color: rgba(14, 165, 233, 0.1);
  border: 1px solid rgba(14, 165, 233, 0.25);
  color: var(--accent-cyan);
  border-radius: 2px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: color 0.15s ease;
  position: relative;
  padding: 4px 0;
}

.nav-link:hover,
.nav-link.active {
  color: #ffffff;
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100%;
  height: 2px;
  background-color: var(--accent-cyan);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: #ffffff;
  color: #030712;
  font-size: 0.92rem;
  font-weight: 600;
  padding: 9px 20px;
  text-decoration: none;
  border-radius: 4px;
  border: 1px solid #ffffff;
  transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  cursor: pointer;
}

.btn-primary:hover {
  background-color: #e5e7eb;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(255, 255, 255, 0.2);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: #111827;
  color: var(--text-main);
  font-size: 0.92rem;
  font-weight: 500;
  padding: 9px 18px;
  text-decoration: none;
  border-radius: 4px;
  border: 1px solid var(--border-subtle);
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  background-color: #1f2937;
  border-color: #374151;
  color: #ffffff;
}

.hamburger-btn {
  display: none;
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 6px;
  border-radius: 4px;
  cursor: pointer;
}

/* 核心专属设计风格：末页只有按钮
   布局：前面全是文字屏，最后一屏正中只有一个按钮。
   细节：按钮宽度等于前一屏标题宽度。
   词：按钮「DeepSeek网页版入口」。
*/

/* 前面纯文字屏 (Text Screen / Manifesto) */
.text-screen-section {
  padding: 100px 0 80px;
  border-bottom: 1px solid var(--border-subtle);
  background: radial-gradient(circle at 50% 20%, rgba(14, 165, 233, 0.05) 0%, transparent 60%);
  text-align: center;
}

.text-screen-inner {
  max-width: 820px;
  margin: 0 auto;
}

.screen-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent-cyan);
  margin-bottom: 20px;
  display: inline-block;
}

/* 前一屏标题：后续终屏按钮宽度严格对齐此标题 */
.screen-manifesto-title {
  font-size: 2.6rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.3;
  color: #ffffff;
  margin: 0 auto 28px;
  display: inline-block; /* 便于测量其精确实际宽度 */
  max-width: 100%;
}

.screen-manifesto-body {
  font-size: 1.12rem;
  line-height: 1.9;
  color: var(--text-muted);
  text-align: justify;
  text-justify: inter-ideograph;
  margin-bottom: 24px;
}

.screen-manifesto-body p {
  margin-bottom: 16px;
}

/* 最后一屏：正中只有一个按钮 (The Final Screen) */
.final-screen-section {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px 24px;
  position: relative;
  background: linear-gradient(180deg, var(--bg-pure) 0%, #080d1a 50%, var(--bg-pure) 100%);
  border-bottom: 1px solid var(--border-subtle);
}

.final-screen-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
}

/* 细节：按钮宽度等于前一屏标题宽度。词：按钮「DeepSeek网页版入口」 */
.the-final-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  padding: 24px 32px;
  font-size: 1.45rem;
  font-weight: 800;
  color: #030712;
  background: linear-gradient(135deg, #ffffff 0%, #e2e8f0 100%);
  text-decoration: none;
  border: 2px solid #ffffff;
  border-radius: 6px;
  box-shadow: 0 0 50px rgba(14, 165, 233, 0.25), 0 20px 40px rgba(0, 0, 0, 0.6);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  text-align: center;
  letter-spacing: -0.01em;
  /* 初始回退最大宽度与前一屏标题一致，JS 将动态计算并精确设为等于前一屏标题宽度 */
  max-width: 100%;
}

.the-final-button:hover {
  background: #ffffff;
  transform: scale(1.015) translateY(-2px);
  box-shadow: 0 0 70px rgba(14, 165, 233, 0.45), 0 25px 50px rgba(0, 0, 0, 0.8);
  border-color: var(--accent-cyan);
}

.the-final-button svg {
  transition: transform 0.2s ease;
}

.the-final-button:hover svg {
  transform: translateX(4px);
}

/* 首屏 #top: 左文右图 */
.hero-section {
  padding: 72px 0 60px;
  position: relative;
  border-bottom: 1px solid var(--border-subtle);
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.hero-content {
  display: flex;
  flex-direction: column;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--accent-cyan);
  background-color: rgba(14, 165, 233, 0.08);
  padding: 4px 12px;
  border: 1px solid rgba(14, 165, 233, 0.2);
  margin-bottom: 20px;
  align-self: flex-start;
  border-radius: 4px;
}

.hero-title {
  font-size: 2.45rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.25;
  color: #ffffff;
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.75;
  margin-bottom: 28px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
}

.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-tag {
  font-size: 0.82rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  padding: 4px 10px;
  border-radius: 4px;
}

/* 首屏右侧视觉叠层 */
.hero-visual {
  position: relative;
}

.hero-img-wrap {
  width: 100%;
  border: 1px solid var(--border-subtle);
  background-color: var(--bg-surface);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
}

.hero-img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

.score-badge-card {
  position: absolute;
  top: -16px;
  right: -14px;
  background-color: rgba(17, 24, 39, 0.95);
  border: 1px solid var(--accent-cyan);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  gap: 16px;
  border-radius: 6px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(10px);
}

.score-big {
  font-size: 1.8rem;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  line-height: 1;
}

.score-latency {
  font-size: 1.4rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--accent-emerald);
  line-height: 1;
}

.score-sub {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.radar-overlay-card {
  position: absolute;
  bottom: -20px;
  left: 18px;
  right: 18px;
  background-color: rgba(17, 24, 39, 0.94);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-subtle);
  padding: 16px 20px;
  border-radius: 6px;
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.5);
}

.radar-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.radar-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: #ffffff;
}

.radar-score-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-cyan);
  background-color: rgba(14, 165, 233, 0.12);
  padding: 2px 6px;
  border-radius: 4px;
  border: 1px solid rgba(14, 165, 233, 0.3);
}

.radar-axes {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.radar-axis-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.76rem;
}

.radar-axis-label {
  width: 48px;
  color: var(--text-muted);
}

.radar-axis-track {
  flex: 1;
  height: 6px;
  background-color: #0b0f19;
  border-radius: 3px;
  overflow: hidden;
}

.radar-axis-fill {
  height: 100%;
  background: linear-gradient(90deg, #0284c7 0%, #38bdf8 100%);
  border-radius: 3px;
}

.radar-axis-val {
  width: 36px;
  text-align: right;
  font-family: var(--font-mono);
  color: #ffffff;
  font-size: 0.74rem;
}

/* 通用区块排版 */
.section {
  padding: 72px 0;
  border-bottom: 1px solid var(--border-subtle);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 48px;
}

.section-tag {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
  display: block;
}

.section-title {
  font-size: 1.85rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.02em;
  margin-bottom: 12px;
}

.section-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* 能力 #ability: 4 列实心卡，推理、搜索、代码、写作 */
.ability-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.ability-solid-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  padding: 28px 24px;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.ability-solid-card:hover {
  background-color: var(--bg-card-hover);
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
}

.ability-icon-wrap {
  width: 44px;
  height: 44px;
  background-color: #0b0f19;
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--accent-cyan);
  border-radius: 4px;
}

.ability-card-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 10px;
}

.ability-card-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 场景 #scenes: 5 列编号卡，01 到 05 */
.scenes-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}

.scene-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  padding: 22px 18px;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.scene-card:hover {
  border-color: var(--accent-cyan);
  background-color: var(--bg-card);
}

.scene-num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent-cyan);
  margin-bottom: 12px;
}

.scene-card-title {
  font-size: 1rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.scene-card-desc {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* 产品 #models: 4 列描边卡，官网、网页版、API、Harness，每张卡里有三条短列表 */
.models-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.model-outline-card {
  background-color: transparent;
  border: 1px solid var(--border-subtle);
  padding: 28px 22px;
  border-radius: 6px;
  transition: all 0.2s ease;
  display: flex;
  flex-direction: column;
}

.model-outline-card:hover {
  border-color: var(--accent-cyan);
  background-color: rgba(17, 24, 39, 0.4);
}

.model-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--accent-cyan);
  border: 1px solid rgba(14, 165, 233, 0.3);
  padding: 2px 6px;
  display: inline-block;
  margin-bottom: 14px;
  align-self: flex-start;
  border-radius: 2px;
}

.model-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 10px;
}

.model-summary {
  font-size: 0.86rem;
  color: var(--text-muted);
  margin-bottom: 18px;
  line-height: 1.5;
}

.model-feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 24px;
  flex: 1;
}

.model-feature-item {
  font-size: 0.82rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
}

.model-feature-item::before {
  content: "—";
  color: var(--accent-cyan);
  font-weight: bold;
}

.model-card-btn {
  display: block;
  text-align: center;
  padding: 9px 0;
  font-size: 0.86rem;
  font-weight: 600;
  color: var(--text-main);
  background-color: #111827;
  border: 1px solid var(--border-subtle);
  text-decoration: none;
  border-radius: 4px;
  transition: all 0.2s ease;
}

.model-card-btn:hover {
  background-color: #1f2937;
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
}

/* 接入 #api: 左文右图，配 2.webp 和 94% / 91% / 88% 三条进度 */
.api-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.progress-group {
  margin-top: 26px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.progress-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.progress-info {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
}

.progress-label {
  color: var(--text-muted);
}

.progress-val {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--accent-cyan);
}

.progress-bar-track {
  height: 8px;
  background-color: #0b0f19;
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, #0284c7, #38bdf8);
}

.media-wrap {
  border: 1px solid var(--border-subtle);
  background-color: #0b0f19;
  border-radius: 6px;
  overflow: hidden;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.media-wrap img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: cover;
}

/* 入口 #download: 改成左图右文，图是 3.webp，和上一块左右对调 */
.download-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

/* 数据 #data: 四个数字（5、12、3、99%）加一条通栏按钮 */
.data-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 32px;
}

.data-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  padding: 30px 18px;
  text-align: center;
  border-radius: 6px;
}

.data-number {
  font-family: var(--font-mono);
  font-size: 2.85rem;
  font-weight: 800;
  color: var(--accent-cyan);
  line-height: 1;
  margin-bottom: 8px;
}

.data-label {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.data-full-btn {
  display: block;
  width: 100%;
  text-align: center;
  padding: 16px;
  font-size: 1.05rem;
  font-weight: 700;
  background-color: #111827;
  color: #ffffff;
  border: 1px solid var(--border-subtle);
  text-decoration: none;
  border-radius: 6px;
  transition: all 0.2s ease;
}

.data-full-btn:hover {
  border-color: var(--accent-cyan);
  color: var(--accent-cyan);
  background-color: #1a2333;
}

/* 问答 #faq: 四条折叠，第一条默认打开 */
.faq-list {
  max-width: 860px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--border-subtle);
  background-color: var(--bg-card);
  border-radius: 6px;
  overflow: hidden;
}

.faq-item summary {
  padding: 18px 22px;
  font-size: 1.02rem;
  font-weight: 600;
  color: #ffffff;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-content {
  padding: 0 22px 18px;
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* 资讯 #news: 六条横排图文，4.webp 到 9.webp 全部露出，没有「查看更多」 */
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.news-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}

.news-card:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
}

.news-thumb {
  width: 100%;
  height: 175px;
  overflow: hidden;
  background-color: #0b0f19;
}

.news-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.news-body {
  padding: 18px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.news-date {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent-cyan);
  margin-bottom: 6px;
}

.news-title {
  font-size: 0.98rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
  line-height: 1.4;
}

.news-desc {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.5;
  flex: 1;
}

/* 页脚: 品牌说明、产品、资源、关于，四列 */
.footer {
  background-color: #030712;
  border-top: 1px solid var(--border-subtle);
  padding: 60px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 36px;
  margin-bottom: 40px;
}

.footer-col-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 16px;
}

.footer-desc {
  font-size: 0.86rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 14px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.86rem;
  transition: color 0.15s ease;
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

.footer-bottom {
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: var(--text-dim);
  font-family: var(--font-mono);
}

/* 响应式断点 */
@media (max-width: 1024px) {
  .scenes-grid {
    grid-template-columns: repeat(3, 1fr);
  }
  .news-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
  }
  .hamburger-btn {
    display: block;
  }
  .hero-layout,
  .api-layout,
  .download-layout {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  .ability-grid,
  .models-grid,
  .data-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .scenes-grid {
    grid-template-columns: 1fr;
  }
  .news-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .screen-manifesto-title {
    font-size: 1.95rem;
  }
  .the-final-button {
    font-size: 1.15rem;
    padding: 18px 24px;
    width: 100% !important; /* 移动窄屏自动撑满 */
  }
}

@media (max-width: 480px) {
  .ability-grid,
  .models-grid,
  .data-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }
}