:root {
    /* Color system */
    --color-primary:#4a6fa5;
    --color-primary-alt:#527db9;
    --color-primary-dark:#2c3e50;
    --color-bg-start:#eef2f7;
    --color-bg-end:#d4dde9;
    --color-surface:rgba(255,255,255,0.72);
    --color-border:rgba(74,111,165,0.25);
    --color-text:#2f3b46;
    --color-text-soft:#44515f;
    --radius-m:14px;
    --elev-1:0 4px 15px -2px rgba(0,0,0,0.07),0 2px 4px rgba(0,0,0,0.06);
    --elev-2:0 10px 25px -5px rgba(0,0,0,0.15),0 4px 10px rgba(0,0,0,0.08);
    --gradient-primary:linear-gradient(115deg,var(--color-primary) 0%,var(--color-primary-dark) 100%);
    --focus-ring:0 0 0 3px rgba(255,255,255,0.8),0 0 0 6px rgba(74,111,165,0.55);
    --transition-fast:.25s cubic-bezier(.4,.2,.2,1);
}
* { margin:0; padding:0; box-sizing:border-box; font-family:'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
html { scroll-behavior:smooth; }
body {
    color: var(--color-text);
    line-height:1.6;
    min-height:100vh; position:relative;
    background:linear-gradient(135deg,var(--color-bg-start) 0%, var(--color-bg-end) 100%);
    background-attachment:fixed;
}
body:before, body:after {
    content:""; position:fixed; inset:0; pointer-events:none; z-index:-1;
    background-image:radial-gradient(circle at 20% 30%, rgba(74,111,165,0.18), transparent 55%),
                        radial-gradient(circle at 78% 70%, rgba(44,62,80,0.18), transparent 60%);
    mix-blend-mode:normal; filter:blur(2px);
}
.container { max-width:1280px; margin:0 auto; padding:22px clamp(16px,2.2vw,42px) 60px; padding-top: 100px; }
header {
    position:relative; text-align:center; padding:54px clamp(16px,3vw,60px) 64px;
    background: var(--gradient-primary);
    color:#fff; border-radius:28px; margin-bottom:38px; overflow:hidden;
    box-shadow: var(--elev-2);
}
header:before { /* subtle grid overlay */
    content:""; position:absolute; inset:0; background-image:linear-gradient(rgba(255,255,255,0.07) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.07) 1px, transparent 1px);
    background-size:38px 38px; opacity:.35; mix-blend-mode:overlay; pointer-events:none;
}
header h1 { font-size:clamp(2.4rem,4.2vw,4rem); margin-bottom:12px; letter-spacing:3px; font-weight:600; }
header p { font-size:clamp(1rem,1.05rem + .2vw,1.25rem); max-width:820px; margin:0 auto 4px; opacity:.95; }
.nav { 
    display:flex; 
    justify-content:flex-end; 
    align-items:center;
    position:fixed; 
    top:0; 
    left:0; 
    right:0; 
    z-index:100; 
    padding:14px 18px; 
    backdrop-filter:blur(12px) saturate(160%); 
    background:rgba(255,255,255,0.95); 
    border-bottom:1px solid rgba(74,111,165,0.15); 
    box-shadow:var(--elev-1);
}

.hamburger-btn {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: var(--color-primary);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 2px 8px rgba(74,111,165,0.3);
    transform: scale(1);
}

.hamburger-btn:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 6px 16px rgba(74,111,165,0.4);
}

.hamburger-btn:active {
    transform: translateY(0) scale(0.95);
}

.hamburger-line {
    width: 24px;
    height: 3px;
    background: white;
    border-radius: 2px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    margin: 2px 0;
    transform-origin: center;
}

.hamburger-btn.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
    background: rgba(255, 255, 255, 0.95);
}

.hamburger-btn.active .hamburger-line:nth-child(2) {
    opacity: 0;
    transform: scale(0);
}

.hamburger-btn.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
    background: rgba(255, 255, 255, 0.95);
}

.hamburger-btn.active {
    background: var(--color-primary-dark);
    transform: rotate(180deg) scale(1.1);
    box-shadow: 0 4px 16px rgba(74,111,165,0.5);
}

.nav-menu {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(15px);
    border-bottom: 1px solid rgba(74,111,165,0.15);
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 99;
}

.nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
}

.nav-menu-list {
    display: flex;
    flex-direction: column;
    padding: 20px;
    gap: 12px;
    max-width: 1280px;
    margin: 0 auto;
}

.nav-menu .nav-btn {
    opacity: 0;
    transform: translateY(-20px) scale(0.9);
}

.nav-menu.active .nav-btn:nth-child(1) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.1s; 
}
.nav-menu.active .nav-btn:nth-child(2) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.15s; 
}
.nav-menu.active .nav-btn:nth-child(3) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.2s; 
}
.nav-menu.active .nav-btn:nth-child(4) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.25s; 
}
.nav-menu.active .nav-btn:nth-child(5) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.3s; 
}
.nav-menu.active .nav-btn:nth-child(6) { 
    animation: slideInDown 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
    animation-delay: 0.35s; 
}

@keyframes slideInDown {
    from {
        opacity: 0;
        transform: translateY(-20px) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}
.nav-btn { 
    position:relative; 
    padding:15px 20px; 
    background:linear-gradient(145deg,#fbfbfc,#f1f5fa); 
    color:var(--color-primary-dark); 
    border:1px solid rgba(74,111,165,0.25); 
    border-radius:12px; 
    cursor:pointer; 
    font-weight:600; 
    font-size:1rem; 
    letter-spacing:.5px; 
    display:flex; 
    align-items:center; 
    justify-content:center;
    gap:8px; 
    transition:var(--transition-fast); 
    box-shadow:0 2px 4px rgba(0,0,0,0.05);
    width: 100%;
    text-align: center;
}
.nav-btn:before { content:""; position:absolute; inset:0; border-radius:inherit; background:linear-gradient(120deg,rgba(74,111,165,0.15),rgba(255,255,255,0)); opacity:0; transition:var(--transition-fast); }
.nav-btn:hover { transform:translateY(-4px); box-shadow:0 6px 16px -2px rgba(0,0,0,0.18); color:var(--color-primary-dark); }
.nav-btn:hover:before { opacity:1; }
.nav-btn:focus-visible { outline:none; box-shadow:var(--focus-ring); }
.nav-btn.active { background:var(--gradient-primary); color:#fff; border-color:transparent; box-shadow:0 8px 18px -4px rgba(44,62,80,0.4); }
.nav-btn.active:before { display:none; }
.section { position:relative; background:var(--color-surface); padding:40px clamp(20px,3.5vw,58px) 46px; border-radius:28px; margin-bottom:44px; box-shadow:var(--elev-1); border:1px solid var(--color-border); display:none; backdrop-filter:blur(18px) saturate(170%); -webkit-backdrop-filter:blur(18px) saturate(170%); transition:opacity .55s ease, transform .55s ease; opacity:0; transform:translateY(26px) scale(.98); }
.section.active { display:block; opacity:1; transform:translateY(0) scale(1); animation:fadeIn .55s ease; }
@keyframes fadeIn { from { opacity:0; transform:translateY(30px) scale(.97);} to { opacity:1; transform:translateY(0) scale(1);} }
h2 { color:var(--color-primary-dark); margin-bottom:22px; padding-bottom:12px; font-weight:600; border-bottom:2px solid var(--color-primary); position:relative; }
h2:after { content:""; position:absolute; left:0; bottom:-2px; width:82px; height:4px; background:linear-gradient(90deg,var(--color-primary),transparent); border-radius:4px; opacity:.75; }
h3 { color:var(--color-primary); margin:24px 0 16px; font-weight:600; letter-spacing:.3px; }
/* Purpose cards layout */
.purpose-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 20px;
}
.purpose-card {
    background:linear-gradient(145deg,#ffffff 0%, #f0f5fa 45%, #e8eff6 100%);
    border:1px solid rgba(74,111,165,0.22);
    padding:24px 22px 22px;
    border-radius: var(--radius-m);
    box-shadow:0 6px 14px -4px rgba(0,0,0,0.15),0 2px 5px rgba(0,0,0,0.07);
    position:relative; overflow:hidden;
    transition:transform .35s cubic-bezier(.34,1.56,.64,1), box-shadow .4s ease;
}
.purpose-card:before {
    content: "";
    position: absolute;
    top: -40px; right: -40px;
    width: 120px; height: 120px;
    background: radial-gradient(circle at center, rgba(74,111,165,0.18), transparent 70%);
    pointer-events: none;
}
.purpose-card:hover { transform:translateY(-10px) scale(1.02); box-shadow:0 16px 32px -8px rgba(0,0,0,0.25); }
.purpose-card i { font-size:1.9rem; color:var(--color-primary); margin-bottom:14px; filter:drop-shadow(0 4px 6px rgba(74,111,165,0.25)); }
.purpose-card h3 { margin:4px 0 14px; font-size:1.08rem; letter-spacing:.6px; color:var(--color-primary-dark); }
.purpose-card p { font-size:.9rem; color:var(--color-text-soft); line-height:1.5; }
.purpose-card small { display:block; margin-top:10px; font-size:.7rem; letter-spacing:.5px; color:#6b7a89; }

.team-members {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.member {
    background:linear-gradient(150deg,#f5f8fb 0%, #eef3f8 60%, #e4ecf4 100%);
    padding:24px 20px 28px;
    border-radius:22px;
    text-align:center;
    transition:transform .5s cubic-bezier(.34,1.56,.64,1), box-shadow .5s ease;
    border:1px solid rgba(74,111,165,0.15);
    position:relative;
    pointer-events: auto;
}
.member:before { 
    content:""; 
    position:absolute; 
    inset:0; 
    background:linear-gradient(120deg,rgba(74,111,165,0.15),rgba(255,255,255,0)); 
    opacity:0; 
    border-radius:inherit; 
    transition:var(--transition-fast); 
    pointer-events: none;
    z-index: 1;
}
.member:hover { transform:translateY(-14px) scale(1.015); box-shadow:0 22px 40px -12px rgba(0,0,0,0.35); }
.member:hover:before { opacity:1; }
.member i { font-size:2.5rem; color:var(--color-primary); margin-bottom:16px; }
.member a.member-link { text-decoration:none; color:inherit; }
.member a.member-link:hover { text-decoration:underline; }
.member img.profile-pic {
    width: 120px;
    height: 120px;
    border-radius: 0;
    object-fit: cover;
    margin-bottom: 15px;
    border:4px solid #ffffff;
    box-shadow:0 8px 22px -8px rgba(0,0,0,0.45),0 2px 6px rgba(0,0,0,0.2);
    background:#e0e6ef;
    transition:var(--transition-fast);
}
.member:hover img.profile-pic { transform:scale(1.04) rotate(.5deg); }

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin: 30px 0;
}

.stat-card {
    background:linear-gradient(140deg,var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color:#fff;
    padding:30px 26px 32px;
    border-radius:24px;
    text-align:center;
    position:relative;
    overflow:hidden;
}
.stat-card:before { content:""; position:absolute; inset:0; background:radial-gradient(circle at 25% 25%, rgba(255,255,255,0.25), transparent 60%); mix-blend-mode:overlay; opacity:.8; }
.stat-card h3 { 
    color:#fff; 
    font-size:2.6rem; 
    margin-bottom:12px; 
    font-weight:600; 
    letter-spacing:1px; 
    text-shadow:0 2px 4px rgba(0,0,0,0.3);
    min-height: 3.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.stat-number {
    display: inline-block;
    font-size: 2.6rem;
    font-weight: 600;
    letter-spacing: 1px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
    color: #fff;
    min-width: 120px;
    text-align: center;
    font-variant-numeric: tabular-nums;
}

.stat-card.animate .stat-number {
    animation: none;
}

@keyframes numberCountDown {
    0% {
        opacity: 0.5;
    }
    100% {
        opacity: 1;
    }
}

.chart-container {
    height:400px; margin:46px 0; position:relative; border:1px solid rgba(74,111,165,0.2); border-radius:22px; background:rgba(255,255,255,0.6); backdrop-filter:blur(10px); box-shadow:0 6px 18px -4px rgba(0,0,0,0.15);
}

.solutions {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.solution {
    background:linear-gradient(150deg,#f7f9fb,#eef3f8 55%,#e8eff6);
    padding:30px 28px 30px;
    border-radius:20px;
    border-left:6px solid var(--color-primary);
    border:1px solid rgba(74,111,165,0.18);
    box-shadow:0 5px 14px -4px rgba(0,0,0,0.18);
    transition:var(--transition-fast);
}
.solution:hover { transform:translateY(-8px) scale(1.015); box-shadow:0 18px 32px -10px rgba(0,0,0,0.35); }
.solution h3 { display:flex; align-items:center; font-size:1.05rem; letter-spacing:.8px; }
.solution h3 i { margin-right:12px; color:var(--color-primary); filter:drop-shadow(0 4px 6px rgba(74,111,165,0.3)); }
.solution ul { margin-left:20px; margin-top:16px; }
.solution li { margin-bottom:11px; }
footer { text-align:center; padding:44px 20px 52px; margin-top:70px; background:var(--color-primary-dark); color:#fff; border-radius:28px; position:relative; overflow:hidden; box-shadow:0 10px 30px -6px rgba(0,0,0,0.4); }
footer:before { content:""; position:absolute; inset:0; background:linear-gradient(120deg,rgba(255,255,255,0.15),rgba(255,255,255,0)); opacity:.45; }
.sources { background:linear-gradient(140deg,#f5f8fb,#eef3f8 65%,#e8eff6); padding:26px 24px 30px; border-radius:22px; margin-top:34px; border:1px solid rgba(74,111,165,0.18); }
@media (max-width: 900px) { .section { padding:36px 26px 42px; } }
@media (max-width: 768px) {
    .container { padding-top: 80px; }
    header { padding:46px 28px 56px; }
    header h1 { font-size:2.5rem; }
    .nav { padding: 12px 18px; }
    .hamburger-btn { width: 36px; height: 36px; }
    .hamburger-line { width: 20px; }
    .nav-menu { top: 60px; }
    .nav-menu-list { padding: 15px; gap: 10px; }
    .nav-btn { padding: 12px 16px; font-size: 0.9rem; }
    .team-members, .stats, .solutions { grid-template-columns:1fr; }
    .chart-container { height:340px; }
}
@media (prefers-reduced-motion: reduce) {
    *, *:before, *:after { animation:none !important; transition:none !important; }
}

.intro-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    color: white;
    opacity: 1;
    transition: opacity 1s ease-out;
}

.intro-overlay.fade-out {
    opacity: 0;
    pointer-events: none;
}

.intro-content {
    text-align: center;
    max-width: 800px;
    padding: 0 20px;
}

.intro-title {
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 700;
    letter-spacing: 8px;
    margin-bottom: 30px;
    opacity: 0;
    animation: slideInFromTop 0.8s ease-out 0s forwards;
}

.intro-subtitle {
    font-size: clamp(1.2rem, 2.5vw, 2rem);
    margin-bottom: 20px;
    opacity: 0;
    animation: slideInFromLeft 0.8s ease-out 0.6s forwards;
}

.intro-description {
    font-size: clamp(1rem, 1.8vw, 1.5rem);
    opacity: 0;
    animation: slideInFromRight 0.8s ease-out 1.2s forwards;
}

.skip-intro {
    position: absolute;
    bottom: 30px;
    right: 30px;
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.5);
    color: white;
    padding: 12px 24px;
    border-radius: 25px;
    cursor: pointer;
    font-size: 0.9rem;
    letter-spacing: 1px;
    transition: all 0.3s ease;
    opacity: 0;
    animation: fadeInButton 0.5s ease-out 2.5s forwards;
}

.skip-intro:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: white;
    transform: translateY(-2px);
}

@keyframes slideInFromTop {
    from {
        opacity: 0;
        transform: translateY(-100px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInFromLeft {
    from {
        opacity: 0;
        transform: translateX(-100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInFromRight {
    from {
        opacity: 0;
        transform: translateX(100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

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

body.intro-active .container {
    opacity: 0;
}

body.intro-active .nav {
    opacity: 0;
}

body.intro-active .nav-menu {
    opacity: 0;
}

body.intro-finished .container {
    opacity: 1;
    transition: opacity 1s ease-in;
}

body.intro-finished .nav {
    opacity: 1;
    transition: opacity 1s ease-in;
}

body.intro-finished .nav-menu {
    opacity: 1;
    transition: opacity 1s ease-in;
}

/* 打字效果樣式 */
.typewriter {
    font-size: clamp(1rem, 1.2rem + .3vw, 1.4rem);
    color: rgba(255, 255, 255, 0.95);
    min-height: 1.6em;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 15px;
}

.typewriter-cursor {
    display: inline-block;
    width: 2px;
    height: 1.2em;
    background-color: rgba(255, 255, 255, 0.9);
    margin-left: 2px;
    animation: blink 1s infinite;
}

.member-link {
    text-decoration: none;
    color: inherit;
    cursor: pointer;
    pointer-events: auto;
    z-index: 100;
    position: relative;
    display: inline-block;
    width: 100%;
    height: 100%;
}
.member-link:hover {
    text-decoration: underline;
    color: #4a6fa5;
}
.member h3 {
    pointer-events: auto;
    position: relative;
    z-index: 101;
}
.member h3 a.member-link {
    pointer-events: auto;
    z-index: 102;
    display: inline;
    width: auto;
    height: auto;
}

@keyframes blink {
    0%, 50% { opacity: 1; }
    51%, 100% { opacity: 0; }
}