:root {
    --primary-color: #D5FF5F;
    --primary-dark: #B8E54E;
    --primary-light: #E8FFB0;
    --text-color: #FFFFFF;
    --text-light: #CCCCCC;
    --background-color: #1E1E25;
    --background-light: #2A2A32;
    --shadow: 0 2px 4px rgba(0,0,0,0.2);
    --transition: all 0.3s ease;
    --animation-duration: 0.5s;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--background-color);
}

header {
    padding: 1rem 2rem;
    background-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

.language-switcher {
    text-align: right;
    display: flex;
    justify-content: flex-end;
    gap: 1rem;
}

.language-switcher a {
    color: var(--background-color);
    text-decoration: none;
    padding: 0.5rem 1rem;
    background-color: var(--primary-color);
    border: none;
    border-radius: 4px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    font-weight: 600;
}

.language-switcher a::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: rgba(255, 255, 255, 0.2);
    transition: var(--transition);
}

.language-switcher a:hover {
    background-color: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: 0 2px 8px rgba(213, 255, 95, 0.3);
}

.language-switcher a:hover::before {
    left: 100%;
}

main {
    max-width: 1200px;
    margin: 80px auto 0;
    padding: 2rem;
    text-align: center;
}

.download-section {
    margin: 3rem 0;
    padding: 4rem 2rem;
    background: linear-gradient(135deg, var(--background-light) 0%, var(--background-color) 100%);
    border-radius: 12px;
    box-shadow: var(--shadow);
    color: var(--primary-color);
    animation: fadeInUp var(--animation-duration) ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.download-section h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.download-section p {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: rgba(255,255,255,0.9);
}

.download-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background-color: var(--primary-color);
    color: var(--background-color);
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.download-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.3);
    background-color: var(--primary-light);
    color: var(--background-color);
}

.action-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
}

.contact-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background-color: transparent;
    color: var(--primary-color);
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    transition: var(--transition);
    border: 2px solid var(--primary-color);
}

.contact-button:hover {
    transform: translateY(-2px);
    background-color: var(--primary-color);
    color: var(--background-color);
    box-shadow: 0 4px 8px rgba(213, 255, 95, 0.3);
}

footer {
    text-align: center;
    padding: 2rem;
    background-color: var(--background-light);
    color: var(--text-light);
}

.features {
    padding: 4rem 2rem;
    background-color: var(--background-light);
    border-radius: 12px;
    margin: 2rem 0;
}

.features h2 {
    font-size: 2rem;
    margin-bottom: 2rem;
    color: var(--primary-color);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.feature-item {
    background: var(--background-light);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    animation: fadeIn var(--animation-duration) ease-out;
    animation-fill-mode: both;
    border: 1px solid rgba(213, 255, 95, 0.1);
}

.feature-item:nth-child(2) {
    animation-delay: 0.2s;
}

.feature-item:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.feature-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

.feature-item h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.feature-item p {
    color: var(--text-light);
}

.app-preview {
    padding: 4rem 2rem;
    text-align: center;
}

.app-preview h2 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.app-preview p {
    color: var(--text-light);
    font-size: 1.2rem;
    max-width: 600px;
    margin: 0 auto;
}

/* 响应式设计 */
@media (max-width: 768px) {
    header {
        padding: 1rem;
    }

    main {
        padding: 1rem;
        margin-top: 60px;
    }

    .language-switcher {
        justify-content: center;
        margin-bottom: 1rem;
    }

    .download-section {
        margin: 2rem 0;
        padding: 2rem 1rem;
    }

    .download-section h1 {
        font-size: 2rem;
    }

    .download-section p {
        font-size: 1rem;
    }

    .download-button {
        padding: 0.8rem 2rem;
        font-size: 1rem;
    }

    .action-buttons {
        flex-direction: column;
        gap: 0.8rem;
    }

    .contact-button {
        padding: 0.8rem 2rem;
        font-size: 1rem;
    }

    .features {
        padding: 2rem 1rem;
    }

    .feature-grid {
        grid-template-columns: 1fr;
    }

    .feature-item {
        margin: 1rem 0;
    }

    .app-preview {
        padding: 2rem 1rem;
    }

    .app-preview h2 {
        font-size: 1.8rem;
    }

    .app-preview p {
        font-size: 1rem;
    }
}

/* 顶部分隔线 */
.header-divider {
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, #D5FF5F 0%, #1E1E25 100%);
    opacity: 0.15;
    margin-top: 0.2rem;
}

/* 顶部header优化 */
.main-header, header {
    padding: 0.1rem 0.5rem !important;
    background: var(--primary-color) !important;
    color: var(--background-color) !important;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}
.header-inner {
    min-height: 38px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.logo {
    display: flex;
    align-items: center;
    gap: 0.2rem;
}
.logo-text {
    color: var(--background-color) !important;
    font-size: 1rem !important;
    font-weight: bold;
    letter-spacing: 1px;
}
.language-switcher {
    width: auto;
    justify-content: flex-end !important;
    margin-bottom: 0 !important;
    display: flex;
    align-items: center;
}
.lang-btn {
    padding: 0.2rem 0.9rem !important;
    font-size: 1rem !important;
    border-radius: 20px !important;
    background: var(--background-color) !important;
    color: var(--primary-color) !important;
    font-weight: 600;
    box-shadow: 0 2px 8px rgba(213,255,95,0.10) !important;
    border: none;
    transition: background 0.2s, box-shadow 0.2s, transform 0.2s, color 0.2s;
}
.lang-btn:hover {
    background: var(--primary-light) !important;
    color: var(--background-color) !important;
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 4px 16px rgba(213,255,95,0.25) !important;
}

@media (max-width: 600px) {
    .main-header, header {
        padding: 0.2rem 0.3rem !important;
        background: linear-gradient(90deg, #1E1E25 80%, #D5FF5F 100%);
        box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    }
    .header-inner {
        flex-direction: row !important;
        align-items: center !important;
        justify-content: space-between !important;
        gap: 0.1rem !important;
        padding: 0 0.3rem !important;
        width: 100%;
    }
    .logo {
        display: flex;
        align-items: center;
        gap: 0.2rem;
    }
    .logo svg {
        width: 18px;
        height: 18px;
    }
    .logo-text {
        font-size: 1rem !important;
        font-weight: bold;
        color: #D5FF5F;
        letter-spacing: 1px;
    }
    .language-switcher {
        width: auto;
        justify-content: flex-end !important;
        margin-bottom: 0 !important;
    }
    .lang-btn {
        padding: 0.1rem 0.5rem !important;
        font-size: 0.9rem !important;
        border-radius: 14px !important;
        background: #D5FF5F;
        color: #1E1E25;
        font-weight: bold;
        box-shadow: 0 1px 4px rgba(213,255,95,0.10) !important;
    }
    main {
        padding: 0.3rem !important;
        margin-top: 48px !important;
    }
    .download-section {
        margin: 0.5rem 0 !important;
        background: var(--background-light) !important;
        background-image: none !important;
    }
    .download-section h1 {
        font-size: 1.4rem !important;
        font-weight: 700 !important;
        margin-bottom: 0.8rem !important;
    }
    .download-section p {
        font-size: 0.9rem !important;
    }
    .download-button {
        padding: 0.5rem 0.9rem !important;
        font-size: 0.9rem !important;
        border-radius: 24px !important;
    }
    .features {
        padding: 1.5rem 0.8rem !important;
        margin: 0.8rem 0 !important;
        background: var(--background-light) !important;
        background-image: none !important;
    }
    .feature-grid {
        gap: 0.4rem !important;
    }
    .feature-item {
        min-height: 110px !important;
        display: flex !important;
        flex-direction: column !important;
        justify-content: center !important;
        padding: 0.8rem 0.5rem !important;
        margin-bottom: 0.3rem !important;
        background: var(--background-light) !important;
    }
    .feature-item h3 {
        font-size: 0.95rem !important;
    }
    .app-preview {
        padding: 0.7rem 0.2rem !important;
    }
    .app-preview h2 {
        font-size: 0.95rem !important;
    }
    .app-preview p {
        font-size: 0.9rem !important;
    }
    footer {
        padding: 0.5rem 0.2rem !important;
        font-size: 0.75rem !important;
        line-height: 1.3 !important;
    }
    footer h5, 
    footer p {
        font-size: 0.75rem !important;
        line-height: 1.3 !important;
    }
    h5 {
        font-size: 0.9rem !important;
    }
    /* 核心功能标题字体减小 */
    .features h2 {
        font-size: 1.1rem !important;
        margin-bottom: 1rem !important;
    }
}