.img-preview-overlay {
      position: fixed; inset: 0;
      background: rgba(0,0,0,0.92);
      z-index: 300;
      display: flex; align-items: center; justify-content: center;
      opacity: 0; pointer-events: none;
      transition: opacity 0.25s ease;
    }
    .img-preview-overlay.show { opacity: 1; pointer-events: auto; }
    .img-preview-overlay img {
      max-width: 95vw; max-height: 90vh;
      border-radius: 8px;
      box-shadow: 0 8px 40px rgba(0,0,0,0.5);
      object-fit: contain;
    }
    .img-preview-close {
      position: absolute; top: 16px; right: 16px;
      width: 40px; height: 40px; border-radius: 50%;
      background: rgba(255,255,255,0.2); color: #fff;
      border: none; cursor: pointer;
      font-size: 18px; display: flex; align-items: center; justify-content: center;
    }
    .img-preview-close:hover { background: rgba(255,255,255,0.35); }

    .toast {
      position: fixed;
      top: 80px;
      left: 50%;
      transform: translateX(-50%) translateY(-20px);
      background: #16a34a;
      color: #fff;
      padding: 12px 28px;
      border-radius: 12px;
      font-size: 14px;
      font-weight: 500;
      box-shadow: 0 8px 24px rgba(22, 163, 74, 0.3);
      z-index: 200;
      opacity: 0;
      pointer-events: none;
      transition: all 0.3s ease;
    }

    .toast.show {
      opacity: 1;
      transform: translateX(-50%) translateY(0);
    }

    .toast.error {
      background: #dc2626;
      box-shadow: 0 8px 24px rgba(220, 38, 38, 0.3);
    }

    .toast.uploading {
      background: #0ea5e9;
      box-shadow: 0 8px 24px rgba(14, 165, 233, 0.35);
      animation: toastPulse 1.6s ease-in-out infinite;
    }

    @keyframes toastPulse {
      0%, 100% { opacity: 1; }
      50% { opacity: 0.8; }
    }

    /* ===== 登录弹窗 ===== */
    .auth-modal-overlay {
      position: fixed;
      top: 0; right: 0; bottom: 0; left: 0;
      background: rgba(15, 23, 42, 0.55);
      z-index: 110;
      display: flex;
      align-items: flex-end;
      justify-content: center;
      padding: 0;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    }

    @media (min-width: 640px) {
      .auth-modal-overlay {
        align-items: center;
        padding: 16px;
      }
    }

    .auth-modal-overlay.show {
      opacity: 1;
      pointer-events: auto;
    }

    .auth-modal {
      background: #fff;
      border-radius: 24px 24px 0 0;
      width: 100%;
      max-width: 100%;
      box-shadow:
        0 -4px 20px rgba(0, 0, 0, 0.06),
        0 -12px 40px rgba(14, 165, 233, 0.04);
      transform: translateY(100%);
      transition: transform 0.45s cubic-bezier(0.32, 0.72, 0, 1);
      position: relative;
      overflow: hidden;
      max-height: 85vh;
      overflow-y: auto;
    }

    @media (min-width: 640px) {
      .auth-modal {
        border-radius: 28px;
        max-width: 440px;
        max-height: none;
        box-shadow:
          0 0 0 1px rgba(0, 0, 0, 0.03),
          0 2px 4px rgba(0, 0, 0, 0.02),
          0 12px 40px rgba(0, 0, 0, 0.08),
          0 24px 80px rgba(14, 165, 233, 0.06);
        transform: translateY(40px) scale(0.92);
      }
    }

    .auth-modal::before {
      content: '';
      position: absolute;
      top: -40%;
      left: -20%;
      width: 140%;
      height: 60%;
      background: radial-gradient(ellipse at 30% 50%, rgba(14, 165, 233, 0.06) 0%, transparent 70%);
      pointer-events: none;
    }

    .auth-modal-overlay.show .auth-modal {
      transform: translateY(0) scale(1);
    }

    @media (min-width: 640px) {
      .auth-modal-overlay.show .auth-modal {
        transform: translateY(0) scale(1);
      }
    }

    .auth-header {
      text-align: center;
      padding: 28px 20px 4px;
      position: relative;
      z-index: 1;
    }

    .auth-header .auth-icon {
      width: 44px;
      height: 44px;
      margin: 0 auto 10px;
      border-radius: 14px;
      background: linear-gradient(135deg, #e0f2fe, #bae6fd);
      display: flex;
      align-items: center;
      justify-content: center;
      animation: authFloat 3s ease-in-out infinite;
    }

    .auth-header .auth-icon svg {
      width: 20px;
      height: 20px;
    }

    @keyframes authFloat {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-3px); }
    }

    .auth-header h2 {
      font-size: 20px;
      font-weight: 700;
      color: #111827;
      margin-bottom: 2px;
      letter-spacing: -0.3px;
      transition: opacity 0.3s ease, transform 0.3s ease;
    }

    .auth-header p {
      font-size: 12px;
      color: #9ca3af;
      transition: opacity 0.3s ease, transform 0.3s ease;
    }

    @media (min-width: 640px) {
      .auth-header {
        padding: 24px 24px 4px;
      }
      .auth-header .auth-icon {
        width: 52px;
        height: 52px;
        border-radius: 16px;
      }
      .auth-header .auth-icon svg {
        width: 24px;
        height: 24px;
      }
      .auth-header h2 {
        font-size: 22px;
      }
      .auth-header p {
        font-size: 13px;
      }
    }

    .auth-tabs {
      display: flex;
      margin: 16px 20px 0;
      background: #f3f4f6;
      border-radius: 12px;
      padding: 3px;
      position: relative;
      z-index: 1;
    }

    @media (min-width: 640px) {
      .auth-tabs {
        margin: 20px 24px 0;
        border-radius: 14px;
        padding: 4px;
      }
    }

    .auth-tab {
      flex: 1;
      padding: 9px;
      text-align: center;
      border-radius: 10px;
      font-size: 13px;
      font-weight: 600;
      color: #6b7280;
      cursor: pointer;
      border: none;
      background: none;
      transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
      position: relative;
    }

    @media (min-width: 640px) {
      .auth-tab {
        padding: 10px;
        border-radius: 11px;
        font-size: 14px;
      }
    }

    .auth-tab.active {
      background: #fff;
      color: #111827;
      box-shadow:
        0 1px 2px rgba(0, 0, 0, 0.04),
        0 2px 8px rgba(0, 0, 0, 0.04);
    }

    .auth-body {
      padding: 20px 20px 24px;
      position: relative;
      z-index: 1;
    }

    @media (min-width: 640px) {
      .auth-body {
        padding: 20px 28px 26px;
      }
    }

    .auth-input-group {
      margin-bottom: 14px;
      opacity: 1;
      transform: translateY(0);
      transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    }

    @media (min-width: 640px) {
      .auth-input-group {
        margin-bottom: 13px;
      }
    }

    .auth-input-group.entering {
      opacity: 0;
      transform: translateY(8px);
    }

    .auth-input-group label {
      display: block;
      font-size: 12px;
      font-weight: 700;
      color: #9ca3af;
      margin-bottom: 8px;
      letter-spacing: 0.5px;
      text-transform: uppercase;
    }

    .auth-input-group input {
      width: 100%;
      padding: 12px 14px;
      border: 2px solid #f3f4f6;
      border-radius: 12px;
      font-size: 15px;
      font-family: inherit;
      color: #111827;
      background: #f9fafb;
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      outline: none;
    }

    @media (min-width: 640px) {
      .auth-input-group input {
        padding: 14px 16px;
        border-radius: 14px;
      }
    }

    .auth-input-group input:hover {
      border-color: #e5e7eb;
      background: #fff;
    }

    .auth-input-group input:focus {
      border-color: #0ea5e9;
      background: #fff;
      box-shadow: 0 0 0 4px rgba(14, 165, 233, 0.06), 0 4px 12px rgba(14, 165, 233, 0.06);
      transform: translateY(-1px);
    }

    .auth-input-group input::placeholder {
      color: #d1d5db;
    }

    .auth-btn {
      width: 100%;
      padding: 13px;
      border-radius: 14px;
      font-size: 15px;
      font-weight: 700;
      cursor: pointer;
      border: none;
      background: linear-gradient(135deg, #0ea5e9, #0284c7);
      color: #fff;
      box-shadow: 0 4px 16px rgba(14, 165, 233, 0.2);
      transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
      margin-top: 8px;
      position: relative;
      overflow: hidden;
    }

    @media (min-width: 640px) {
      .auth-btn {
        padding: 14px;
        border-radius: 16px;
        font-size: 16px;
        margin-top: 8px;
      }
    }

    .auth-btn::after {
      content: '';
      position: absolute;
      top: 0; right: 0; bottom: 0; left: 0;
      background: linear-gradient(135deg, rgba(255,255,255,0.15), transparent);
      opacity: 0;
      transition: opacity 0.3s ease;
    }

    .auth-btn:hover {
      box-shadow: 0 8px 28px rgba(14, 165, 233, 0.35);
      transform: translateY(-2px);
    }

    .auth-btn:hover::after {
      opacity: 1;
    }

    .auth-btn:active {
      transform: scale(0.96);
      transition: transform 0.1s ease;
    }

    .auth-btn:disabled {
      opacity: 0.5;
      cursor: not-allowed;
      transform: none;
      box-shadow: none;
    }

    .auth-close {
      position: absolute;
      top: 14px;
      right: 14px;
      width: 34px;
      height: 34px;
      border-radius: 50%;
      background: rgba(243, 244, 246, 0.9);
      border: none;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 15px;
      color: #9ca3af;
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      z-index: 2;
    }

    .auth-close:hover {
      background: #fee2e2;
      color: #ef4444;
      transform: rotate(90deg) scale(1.1);
    }

    /* 输入框抖动动画 */
    @keyframes shake {
      0%, 100% { transform: translateX(0); }
      20% { transform: translateX(-6px); }
      40% { transform: translateX(6px); }
      60% { transform: translateX(-4px); }
      80% { transform: translateX(4px); }
    }

    .auth-input-group.shake input {
      animation: shake 0.5s ease;
      border-color: #fca5a5 !important;
    }

    /* 导航栏用户信息 */
    .user-info {
      display: flex;
      align-items: center;
      gap: 8px;
      cursor: pointer;
      padding: 4px 8px;
      border-radius: 8px;
      transition: background 0.15s ease;
    }

    .user-info:hover {
      background: rgba(14, 165, 233, 0.06);
    }

    .user-avatar {
      width: 32px;
      height: 32px;
      border-radius: 50%;
      background: linear-gradient(135deg, #e0f2fe, #bae6fd);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 14px;
      font-weight: 700;
      color: #0ea5e9;
    }

    .user-name {
      font-size: 13px;
      font-weight: 600;
      color: #374151;
      display: none;
    }

    @media (min-width: 640px) {
      .user-name {
        display: block;
      }
    }

    /* ===== 头像上传 ===== */
    .avatar-upload {
      display: flex;
      flex-direction: column;
      align-items: center;
      margin-bottom: 16px;
    }

    @media (min-width: 640px) {
      .avatar-upload {
        margin-bottom: 20px;
      }
    }

    .avatar-preview {
      width: 64px;
      height: 64px;
      border-radius: 50%;
      background: #f3f4f6;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      position: relative;
      overflow: hidden;
      transition: all 0.3s ease;
      border: 3px solid transparent;
    }

    @media (min-width: 640px) {
      .avatar-preview {
        width: 72px;
        height: 72px;
      }
    }

    /* ===================================================================