/* CSS Custom Variables for Premium Theme - Default: Light Theme (白天) */
:root {
    --bg-color: #f5f7fb;
    --card-bg: rgba(255, 255, 255, 0.45);
    --card-border: rgba(255, 255, 255, 0.6);
    --card-hover-border: rgba(255, 255, 255, 0.95);
    
    --text-primary: #0f172a;
    --text-secondary: #334155;
    --text-muted: #64748b;
    
    --primary: #0284c7; /* Sky Blue */
    --primary-glow: rgba(2, 132, 199, 0.1);
    --secondary: #0ea5e9; /* Teal-ish Sky */
    --secondary-glow: rgba(14, 165, 233, 0.1);
    
    --accent-purple: #7c3aed;
    --accent-teal: #0f766e;
    --accent-orange: #ea580c;
    --accent-red: #e11d48;
    
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.06);
    
    --font-sans: 'Outfit', 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-mono: 'Fira Code', monospace;
    
    --transition-smooth: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    
    /* Theme specific overrides */
    --title-gradient: linear-gradient(135deg, #0f172a 60%, var(--primary));
    --input-bg: rgba(255, 255, 255, 0.7);
    --input-border: rgba(0, 0, 0, 0.08);
    --input-focus-bg: rgba(255, 255, 255, 0.95);
    --filter-active-text: #ffffff;
    --card-glow-bg: radial-gradient(800px circle at var(--x, 50%) var(--y, 50%), rgba(2, 132, 199, 0.08), transparent 40%);
    --blob-opacity: 0.11;
    --blob-blend-mode: normal;
    
    --btn-bg: rgba(0, 0, 0, 0.04);
    --btn-border: rgba(0, 0, 0, 0.05);
    --btn-hover-bg: rgba(0, 0, 0, 0.08);
}

/* Night Theme (夜晚) Override */
body.dark-theme {
    --bg-color: #070b15;
    --card-bg: rgba(13, 22, 41, 0.55);
    --card-border: rgba(255, 255, 255, 0.07);
    --card-hover-border: rgba(255, 255, 255, 0.18);
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --primary: #00f2fe; /* Electric Teal */
    --primary-glow: rgba(0, 242, 254, 0.2);
    --secondary: #4facfe; /* Neon Blue */
    --secondary-glow: rgba(79, 172, 254, 0.2);
    
    --accent-purple: #c084fc;
    --accent-teal: #2dd4bf;
    --accent-orange: #fb923c;
    --accent-red: #f87171;
    
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
    
    /* Theme specific overrides */
    --title-gradient: linear-gradient(135deg, #ffffff 60%, var(--primary));
    --input-bg: rgba(0, 0, 0, 0.25);
    --input-border: rgba(255, 255, 255, 0.06);
    --input-focus-bg: rgba(0, 0, 0, 0.35);
    --filter-active-text: #070b15;
    --card-glow-bg: radial-gradient(800px circle at var(--x, 50%) var(--y, 50%), rgba(255, 255, 255, 0.06), transparent 40%);
    --blob-opacity: 0.22;
    --blob-blend-mode: screen;
    
    --btn-bg: rgba(255, 255, 255, 0.05);
    --btn-border: rgba(255, 255, 255, 0.06);
    --btn-hover-bg: rgba(255, 255, 255, 0.12);
}

/* Reset & Base Styles */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
    position: relative;
    line-height: 1.6;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-color);
}
::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--primary);
}

/* Background Animated Blobs */
.blob-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(140px);
    opacity: var(--blob-opacity);
    mix-blend-mode: var(--blob-blend-mode);
    animation: float-blobs 20s infinite alternate;
    transition: opacity 0.5s ease, mix-blend-mode 0.5s ease;
}

.blob-purple {
    top: -10%;
    right: 10%;
    width: 450px;
    height: 450px;
    background: linear-gradient(135deg, #7c3aed, #c084fc);
    animation-delay: 0s;
}

.blob-teal {
    bottom: -10%;
    left: 5%;
    width: 500px;
    height: 500px;
    background: linear-gradient(135deg, #0d9488, #2dd4bf);
    animation-delay: 2s;
}

.blob-blue {
    top: 40%;
    left: 45%;
    width: 400px;
    height: 400px;
    background: linear-gradient(135deg, #2563eb, #38bdf8);
    animation-delay: 4s;
}

@keyframes float-blobs {
    0% {
        transform: translate(0px, 0px) scale(1);
    }
    50% {
        transform: translate(40px, -60px) scale(1.1);
    }
    100% {
        transform: translate(-30px, 40px) scale(0.95);
    }
}

/* App Container Layout */
.app-container {
    max-width: 1100px;
    margin: 40px auto;
    padding: 0 24px;
    flex: 1;
    width: 100%;
}

/* Glassmorphism General Style */
.glass-panel {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    box-shadow: var(--glass-shadow);
}

/* 1. Profile / Header Card */
.profile-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    box-shadow: var(--glass-shadow);
    padding: 32px;
    margin-bottom: 30px;
    position: relative;
    overflow: hidden;
    transition: var(--transition-smooth);
}

.profile-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
}

.profile-card:hover {
    border-color: rgba(255, 255, 255, 0.12);
    box-shadow: 0 12px 40px 0 rgba(0, 0, 0, 0.45);
}

.profile-header {
    display: flex;
    align-items: center;
    gap: 30px;
    margin-bottom: 24px;
}

@media (max-width: 640px) {
    .profile-header {
        flex-direction: column;
        text-align: center;
        gap: 20px;
    }
}

/* Profile Avatar and Glow */
.avatar-wrapper {
    position: relative;
    width: 96px;
    height: 96px;
    flex-shrink: 0;
}

.profile-avatar {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid rgba(255, 255, 255, 0.2);
    z-index: 1;
    position: relative;
}

.avatar-glow {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    filter: blur(10px);
    opacity: 0.6;
    animation: pulse-glow 3s infinite alternate;
}

@keyframes pulse-glow {
    0% {
        transform: scale(0.95);
        opacity: 0.4;
    }
    100% {
        transform: scale(1.05);
        opacity: 0.8;
    }
}

/* Profile Info */
.profile-name {
    font-size: 2.2rem;
    font-weight: 800;
    background: var(--title-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
    gap: 12px;
    letter-spacing: -0.5px;
    transition: background 0.4s ease;
}

@media (max-width: 640px) {
    .profile-name {
        justify-content: center;
    }
}

.title-badge {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--primary);
    background: var(--primary-glow);
    padding: 4px 10px;
    border-radius: 20px;
    border: 1px solid rgba(0, 242, 254, 0.3);
}

.profile-bio {
    color: var(--text-secondary);
    font-size: 1.05rem;
    margin-top: 8px;
    max-width: 680px;
}

/* Social Buttons */
.social-links {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

@media (max-width: 640px) {
    .social-links {
        justify-content: center;
    }
}

.social-btn {
    text-decoration: none;
    color: var(--text-primary);
    background: var(--btn-bg);
    border: 1px solid var(--btn-border);
    padding: 10px 18px;
    border-radius: 12px;
    font-size: 0.95rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition-smooth);
}

.social-btn:hover {
    background: var(--btn-hover-bg);
    border-color: var(--card-hover-border);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

#social-github:hover {
    color: #ffffff;
    box-shadow: 0 0 15px rgba(255, 255, 255, 0.15);
}

#social-email:hover {
    color: var(--accent-purple);
    box-shadow: 0 0 15px rgba(192, 132, 252, 0.15);
}

#social-blog:hover {
    color: var(--primary);
    box-shadow: 0 0 15px rgba(0, 242, 254, 0.15);
}


/* 2. Control Panel (Search & Filter) */
.control-panel {
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    box-shadow: var(--glass-shadow);
    padding: 24px;
    margin-bottom: 30px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* Search Box */
.search-box-wrapper {
    position: relative;
    width: 100%;
}

.search-icon {
    position: absolute;
    left: 20px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    font-size: 1.1rem;
    pointer-events: none;
    transition: var(--transition-smooth);
}

.search-box-wrapper input {
    width: 100%;
    padding: 16px 50px 16px 55px;
    background: var(--input-bg);
    border: 1px solid var(--input-border);
    border-radius: 16px;
    color: var(--text-primary);
    font-family: var(--font-sans);
    font-size: 1.05rem;
    outline: none;
    transition: var(--transition-smooth);
}

.search-box-wrapper input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 16px rgba(0, 242, 254, 0.15);
    background: var(--input-focus-bg);
}

.search-box-wrapper input:focus + .search-icon {
    color: var(--primary);
}

/* Clear Input Button */
.clear-btn {
    position: absolute;
    right: 18px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.2rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-smooth);
    padding: 4px;
}

.clear-btn:hover {
    color: var(--text-primary);
}

.clear-btn.visible {
    opacity: 1;
    visibility: visible;
}

/* Filter Tabs */
.filter-tabs {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.filter-btn {
    background: transparent;
    border: 1px solid rgba(255, 255, 255, 0.08);
    color: var(--text-secondary);
    padding: 8px 18px;
    border-radius: 12px;
    cursor: pointer;
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 500;
    transition: var(--transition-smooth);
}

.filter-btn:hover {
    background: rgba(255, 255, 255, 0.04);
    color: var(--text-primary);
}

.filter-btn.active {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: var(--filter-active-text);
    border-color: transparent;
    font-weight: 600;
    box-shadow: 0 0 15px rgba(0, 242, 254, 0.3);
}


/* 3. Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

@media (max-width: 768px) {
    .projects-grid {
        grid-template-columns: 1fr;
    }
}

.project-card {
    position: relative;
    border-radius: 20px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    transition: var(--transition-smooth);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

/* Card Glow Effect on Hover */
.card-glow {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--card-glow-bg);
    pointer-events: none;
    z-index: 1;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.project-card:hover .card-glow {
    opacity: 1;
}

.card-content {
    padding: 28px;
    display: flex;
    flex-direction: column;
    height: 100%;
    z-index: 2;
    position: relative;
}

.project-card:hover {
    transform: translateY(-6px);
    border-color: var(--card-hover-border);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4), 0 0 20px rgba(0, 242, 254, 0.08);
}

/* Card Header */
.project-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 16px;
}

.project-icon-wrapper {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.05);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    border: 1px solid rgba(255, 255, 255, 0.06);
}

.font-python {
    color: var(--accent-teal);
    background: rgba(45, 212, 191, 0.1);
    border-color: rgba(45, 212, 191, 0.2);
}

.font-web {
    color: var(--accent-purple);
    background: rgba(192, 132, 252, 0.1);
    border-color: rgba(192, 132, 252, 0.2);
}

.font-game {
    color: var(--accent-orange);
    background: rgba(251, 146, 60, 0.1);
    border-color: rgba(251, 146, 60, 0.2);
}

.project-title-area {
    display: flex;
    flex-direction: column;
}

.project-title {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
}

.project-subtitle {
    font-size: 0.85rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
    margin-top: 2px;
}

/* Card Description */
.project-desc {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 20px;
    flex-grow: 1;
}

/* Tech Tags */
.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 24px;
}

.tech-tag {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.06);
    padding: 4px 10px;
    border-radius: 8px;
}

/* Card Action Buttons */
.project-actions {
    display: flex;
    gap: 12px;
}

.action-btn {
    flex: 1;
    text-decoration: none;
    padding: 10px 14px;
    border-radius: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    text-align: center;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    transition: var(--transition-smooth);
    cursor: pointer;
}

.action-btn.primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #070b15;
}

.action-btn.primary:hover {
    box-shadow: 0 0 15px rgba(0, 242, 254, 0.4);
    transform: translateY(-1px);
}

.action-btn.secondary {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.06);
    color: var(--text-primary);
}

.action-btn.secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.15);
}

.action-btn.disabled {
    opacity: 0.4;
    cursor: not-allowed;
    background: rgba(255, 255, 255, 0.02) !important;
    border-color: rgba(255, 255, 255, 0.02) !important;
    color: var(--text-muted) !important;
}

/* Card animation on filter */
.project-card.hidden {
    opacity: 0;
    transform: scale(0.9) translateY(20px);
    display: none;
}


/* 4. No Results Placeholder Card */
.no-results-card {
    background: var(--card-bg);
    border: 1px dashed rgba(255, 255, 255, 0.15);
    border-radius: 20px;
    padding: 60px 20px;
    text-align: center;
    grid-column: 1 / -1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 16px;
}

.no-results-card i {
    font-size: 3rem;
    color: var(--text-muted);
}

.no-results-card p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.no-results-card button {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--primary);
    padding: 10px 20px;
    border-radius: 10px;
    cursor: pointer;
    font-family: var(--font-sans);
    font-weight: 600;
    transition: var(--transition-smooth);
}

.no-results-card button:hover {
    background: var(--primary-glow);
    border-color: var(--primary);
}

.no-results-card.hidden {
    display: none;
}


/* 5. Footer Section */
.app-footer {
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding: 30px 24px;
    margin-top: 60px;
    text-align: center;
    background: rgba(3, 7, 18, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.footer-content {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 8px;
    color: var(--text-muted);
    font-size: 0.88rem;
}

.glow-text {
    color: var(--primary);
    text-shadow: 0 0 10px rgba(0, 242, 254, 0.3);
}

.tech-stack-indicator {
    font-size: 0.8rem;
}

/* Theme Toggle Button Styles */
.theme-toggle-btn {
    position: absolute;
    top: 24px;
    right: 24px;
    background: var(--btn-bg);
    border: 1px solid var(--btn-border);
    color: var(--text-secondary);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.15rem;
    transition: var(--transition-smooth);
    z-index: 10;
    box-shadow: var(--shadow-sm);
}

.theme-toggle-btn:hover {
    background: var(--btn-hover-bg);
    border-color: var(--card-hover-border);
    color: var(--primary);
    transform: scale(1.08) rotate(15deg);
    box-shadow: var(--shadow-md);
}

.theme-toggle-btn:active {
    transform: scale(0.95);
}

/* Sun & Moon Icons visibility & animations */
.theme-toggle-btn .icon-sun {
    display: none;
}

.theme-toggle-btn .icon-moon {
    display: block;
}

body.dark-theme .theme-toggle-btn .icon-sun {
    display: block;
    animation: rotate-sun 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

body.dark-theme .theme-toggle-btn .icon-moon {
    display: none;
}

@keyframes rotate-sun {
    from {
        transform: rotate(-90deg) scale(0.5);
        opacity: 0;
    }
    to {
        transform: rotate(0deg) scale(1);
        opacity: 1;
    }
}

/* Global Theme Transition */
body, 
.profile-card, 
.control-panel, 
.project-card, 
input, 
.filter-btn, 
.social-btn, 
.action-btn, 
.app-footer,
.project-icon-wrapper {
    transition: background-color 0.4s ease, 
                border-color 0.4s ease, 
                color 0.4s ease, 
                box-shadow 0.4s ease, 
                opacity 0.4s ease, 
                background 0.4s ease;
}