/* ============================================================================
   知萃 DistillAI — 跨页面共享样式
   版本: v4.0
   依赖: distillai-design-tokens.css, distillai-base.css
   用途: 导航栏 / Footer / 登录弹窗 / 容器
   ============================================================================ */

/* ==========================================================================
   §1 Navigation — 白底胶囊风格（sticky 顶部导航）
   ========================================================================== */

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--zd-paper);
  border-bottom: 1px solid var(--zd-line);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.nav-inner {
  max-width: 1260px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--zd-space-6);
  height: 64px;
}

/* ── Logo ── */
.nav-logo {
  display: flex;
  align-items: center;
  gap: 9px;
  text-decoration: none;
  flex-shrink: 0;
}

.nav-logo-icon {
  position: relative;
  width: 28px;
  height: 28px;
  border-radius: var(--zd-radius-appicon);
  background: linear-gradient(145deg, var(--zd-navy-900) 0%, var(--zd-navy-900) 40%, var(--zd-navy-950) 100%);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, .05), 0 2px 6px rgba(0, 0, 0, .2);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.nav-logo-icon::before {
  content: '';
  position: absolute;
  top: 12%;
  left: 18%;
  width: 30%;
  height: 20%;
  background: rgba(255, 255, 255, .04);
  border-radius: 50%;
}

.nav-logo-icon svg {
  width: 16px;
  height: 18px;
  position: relative;
  z-index: 1;
}

.nav-logo-icon .drop-body {
  fill: url(#zd-drop-grad);
  filter: drop-shadow(0 1px 2px rgba(0, 0, 0, .3));
}

.nav-logo-icon .drop-highlight {
  fill: rgba(255, 255, 255, .25);
}

.nav-logo-text {
  font-weight: 700;
  font-size: 16px;
  color: var(--zd-ink);
  white-space: nowrap;
  letter-spacing: -0.01em;
}

.nav-logo-text span {
  color: var(--zd-mint-500);
  font-weight: 500;
}

/* ── Nav Links ── */
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--zd-space-1);
}

.nav-links a {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--zd-muted);
  padding: var(--zd-space-1) var(--zd-space-3);
  border-radius: var(--zd-radius-xs);
  transition: all var(--zd-duration-fast) var(--zd-ease-out);
  text-decoration: none;
}

.nav-links a:hover {
  color: var(--zd-ink);
  background: var(--zd-cloud);
  text-decoration: none;
}

/* ── Primary Action Button ── */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--zd-space-2);
  padding: 0 var(--zd-space-8);
  height: 52px;
  font-weight: 700;
  font-size: 1rem;
  color: var(--zd-navy-900);
  background: var(--zd-mint-500);
  border-radius: var(--zd-radius-button);
  transition: all var(--zd-duration-fast) var(--zd-ease-out);
  white-space: nowrap;
  flex-shrink: 0;
  cursor: pointer;
  border: none;
  font-family: inherit;
}
.btn-primary:hover {
  background: var(--zd-mint-400);
  transform: translateY(-1px);
  box-shadow: 0 6px 24px rgba(98, 227, 167, .35);
}
.btn-primary:active {
  background: var(--zd-mint-600);
  transform: translateY(0);
}
.btn-primary:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}
.btn-primary svg {
  width: 18px;
  height: 18px;
}

/* ── Login Button ── */
.btn-login {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--zd-space-1) var(--zd-space-5);
  font-weight: 600;
  font-size: 0.875rem;
  border-radius: var(--zd-radius-button);
  background: var(--zd-navy-800);
  color: var(--zd-paper);
  transition: all var(--zd-duration-fast) var(--zd-ease-out);
  height: 36px;
  min-height: 44px;
  white-space: nowrap;
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.btn-login:hover {
  background: var(--zd-navy-700);
  box-shadow: 0 4px 14px rgba(10, 20, 36, .25);
  transform: translateY(-1px);
}

.btn-login:active {
  background: var(--zd-navy-950);
  transform: translateY(0);
}
.btn-login:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}

/* ── Mobile Nav Toggle ── */
.nav-toggle {
  display: none;
  width: 36px;
  height: 36px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  border-radius: var(--zd-radius-xs);
  color: var(--zd-muted);
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

.nav-toggle svg {
  width: 20px;
  height: 20px;
}

/* ── Mobile Menu Drawer ── */
.nav-mobile-menu {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--zd-paper);
  border-bottom: 1px solid var(--zd-line);
  padding: var(--zd-space-4);
  z-index: 99;
  box-shadow: var(--zd-shadow-md);
  flex-direction: column;
  gap: var(--zd-space-2);
}

.nav-mobile-menu.open {
  display: flex;
}

.nav-mobile-menu a {
  display: block;
  font-size: 1rem;
  font-weight: 500;
  color: var(--zd-text);
  padding: var(--zd-space-3) var(--zd-space-4);
  border-radius: var(--zd-radius-xs);
  text-decoration: none;
  transition: background var(--zd-duration-fast) var(--zd-ease-out);
}

.nav-mobile-menu a:hover {
  background: var(--zd-cloud);
  text-decoration: none;
}

/* ==========================================================================
   §2 Footer — 深海军蓝品牌区
   ========================================================================== */

.footer {
  padding: var(--zd-space-10) 0;
  background: var(--zd-navy-900);
  text-align: center;
}

.footer-inner {
  max-width: 1260px;
  margin: 0 auto;
  padding: 0 var(--zd-space-6);
}

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin-bottom: var(--zd-space-3);
  text-decoration: none;
}

.footer-logo-icon {
  width: 22px;
  height: 22px;
  border-radius: var(--zd-radius-appicon);
  background: linear-gradient(145deg, var(--zd-navy-900) 0%, var(--zd-navy-900) 40%, var(--zd-navy-950) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.footer-logo-icon svg {
  width: 12px;
  height: 14px;
}

.footer-logo-icon .drop-body {
  fill: url(#zd-drop-grad);
  filter: drop-shadow(0 1px 2px rgba(0, 0, 0, .3));
}

.footer-logo-icon .drop-highlight {
  fill: rgba(255, 255, 255, .25);
}

.footer-logo-text {
  font-weight: 700;
  font-size: 14px;
  color: var(--zd-paper);
}

.footer-logo-text span {
  color: var(--zd-mint-400);
  font-weight: 500;
}

.footer p {
  font-size: 0.825rem;
  color: rgba(255, 255, 255, .3);
  margin: 0;
}

/* Footer links row */
.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--zd-space-6);
  margin-bottom: var(--zd-space-5);
}

.footer-links a {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, .55);
  text-decoration: none;
  transition: color var(--zd-duration-fast) var(--zd-ease-out);
}

.footer-links a:hover {
  color: var(--zd-mint-400);
  text-decoration: none;
}

.footer-divider {
  width: 60px;
  height: 1px;
  background: rgba(255, 255, 255, .1);
  margin: 0 auto var(--zd-space-5);
}

/* ==========================================================================
   §3 Login Modal — 登录弹窗
   ========================================================================== */

.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(10, 20, 36, .55);
  display: flex;
  align-items: center;
  justify-content: center;
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  animation: overlay-in var(--zd-duration-normal) var(--zd-ease-out);
}

@keyframes overlay-in {
  from { opacity: 0; }
  to   { opacity: 1; }
}
.modal-overlay[hidden] {
  display: none !important;
}


.modal {
  background: var(--zd-paper);
  border-radius: var(--zd-radius-panel);
  box-shadow: var(--zd-shadow-floating);
  max-width: 440px;
  width: 90vw;
  animation: modal-in var(--zd-duration-normal) var(--zd-ease-out);
  overflow: hidden;
}

@keyframes modal-in {
  from { opacity: 0; transform: scale(.95) translateY(10px); }
  to   { opacity: 1; transform: scale(1) translateY(0); }
}

.modal-header {
  padding: var(--zd-space-6) var(--zd-space-6) var(--zd-space-3);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-header h2 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--zd-ink);
  margin: 0;
}

.modal-close {
  width: 32px;
  height: 32px;
  min-height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--zd-muted);
  transition: all var(--zd-duration-fast) var(--zd-ease-out);
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

.modal-close:hover {
  background: var(--zd-line);
  color: var(--zd-ink);
}

.modal-close svg {
  width: 18px;
  height: 18px;
}

.modal-body {
  padding: var(--zd-space-3) var(--zd-space-6) var(--zd-space-6);
  font-size: 0.9375rem;
  color: var(--zd-text);
  line-height: 1.6;
}

.modal-body p {
  color: var(--zd-muted);
  font-size: 0.875rem;
  margin-bottom: var(--zd-space-5);
}

/* Login form fields */
.login-field {
  margin-bottom: var(--zd-space-4);
}

.login-field label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--zd-text);
  margin-bottom: var(--zd-space-1);
}

.login-field input {
  width: 100%;
  height: 44px;
  padding: 0 var(--zd-space-4);
  font-size: 0.9375rem;
  color: var(--zd-ink);
  background: var(--zd-cloud);
  border: 1.5px solid var(--zd-line);
  border-radius: var(--zd-radius-button);
  outline: none;
  transition: border-color var(--zd-duration-fast) var(--zd-ease-out),
              box-shadow var(--zd-duration-fast) var(--zd-ease-out);
}

.login-field input::placeholder {
  color: var(--zd-dim);
}

.login-field input:focus {
  border-color: var(--zd-mint-500);
  box-shadow: 0 0 0 3px rgba(98, 227, 167, .12);
}

.login-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 46px;
  font-weight: 700;
  font-size: 0.95rem;
  border-radius: var(--zd-radius-button);
  background: var(--zd-mint-500);
  color: var(--zd-navy-900);
  border: none;
  cursor: pointer;
  font-family: inherit;
  transition: all var(--zd-duration-fast) var(--zd-ease-out);
  margin-top: var(--zd-space-2);
}

.login-btn:hover {
  background: var(--zd-mint-400);
  box-shadow: 0 6px 20px rgba(98, 227, 167, .3);
  transform: translateY(-1px);
}

.login-btn:active {
  background: var(--zd-mint-600);
  transform: translateY(0);
}
.login-btn:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}

.login-alt {
  text-align: center;
  margin-top: var(--zd-space-4);
  font-size: 0.8rem;
  color: var(--zd-dim);
}

.login-alt a {
  color: var(--zd-mint-500);
  font-weight: 600;
  text-decoration: none;
}

.login-alt a:hover {
  text-decoration: underline;
}

/* ==========================================================================
   §4 Shared Container Utility
   ========================================================================== */

.container-site {
  width: 100%;
  max-width: 1260px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--zd-space-6);
  padding-right: var(--zd-space-6);
}

/* Section label shared */
.section-label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--zd-mint-500);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--zd-space-2);
}

.section-heading {
  font-size: clamp(1.375rem, 2.5vw, 2rem);
  font-weight: 700;
  color: var(--zd-ink);
  letter-spacing: -0.01em;
  margin-bottom: var(--zd-space-10);
}

/* ==========================================================================
   §5 Responsive — Shared Components
   ========================================================================== */

/* Tablet 768–1199px */
@media (max-width: 1199px) {
  .container-site {
    padding-left: var(--zd-space-4);
    padding-right: var(--zd-space-4);
  }
}

/* Mobile ≤ 767px */
@media (max-width: 767px) {
  .nav-links {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .nav-inner {
    padding: 0 var(--zd-space-4);
    height: 56px;
  }

  .btn-login {
    padding: var(--zd-space-1) var(--zd-space-4);
    font-size: 0.8125rem;
    height: 32px;
  }

  .container-site {
    padding-left: var(--zd-space-4);
    padding-right: var(--zd-space-4);
  }

  .footer {
    padding: var(--zd-space-8) 0;
  }

  .footer-links {
    gap: var(--zd-space-4);
  }

  .modal {
    width: 95vw;
    max-width: none;
  }

  .modal-header {
    padding: var(--zd-space-5) var(--zd-space-5) var(--zd-space-2);
  }

  .modal-body {
    padding: var(--zd-space-2) var(--zd-space-5) var(--zd-space-5);
  }
}

/* Compact ≤ 420px */
@media (max-width: 420px) {
  .nav-inner {
    padding: 0 var(--zd-space-3);
  }

  .container-site {
    padding-left: var(--zd-space-3);
    padding-right: var(--zd-space-3);
  }

  .nav-logo-text {
    font-size: 14px;
  }

  .footer-inner {
    padding: 0 var(--zd-space-3);
  }

  .footer-links {
    flex-direction: column;
    align-items: center;
    gap: var(--zd-space-3);
  }
}