:root {
    --bg-main: #0a0a1a;
    --bg-card: rgba(255, 255, 255, 0.04);
    --bg-card-hover: rgba(255, 255, 255, 0.06);
    --border: rgba(255, 255, 255, 0.08);
    --text-primary: #f1f1f7;
    --text-secondary: #8b8da3;
    --accent-1: #6c5ce7;
    --accent-2: #a855f7;
    --accent-3: #38bdf8;
    --gradient: linear-gradient(135deg, var(--accent-1), var(--accent-2), var(--accent-3));
    --gradient-btn: linear-gradient(135deg, #6c5ce7, #a855f7);
    --success: #22c55e;
    --shadow-glow: 0 0 60px rgba(108, 92, 231, 0.15);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --radius: 16px;
    --radius-sm: 10px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* === Animated Background === */
.bg-grid {
    position: fixed;
    inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
    background-size: 60px 60px;
    z-index: 0;
}

.bg-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.4;
    z-index: 0;
    animation: floatGlow 12s ease-in-out infinite alternate;
}

.bg-glow-1 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(108, 92, 231, 0.35), transparent 70%);
    top: -150px;
    left: -100px;
}

.bg-glow-2 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(56, 189, 248, 0.25), transparent 70%);
    bottom: -100px;
    right: -50px;
    animation-delay: -6s;
}

@keyframes floatGlow {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(40px, 30px) scale(1.15); }
}

/* === App Layout === */
.app {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* === Header === */
.header {
    width: 100%;
    padding: 24px 40px;
    display: flex;
    justify-content: center;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.logo-icon {
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: var(--gradient-btn);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    color: #fff;
    box-shadow: 0 4px 15px rgba(108, 92, 231, 0.35);
}

/* === Hero === */
.hero {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 20px 20px 60px;
    max-width: 720px;
    width: 100%;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    border-radius: 100px;
    background: rgba(108, 92, 231, 0.15);
    border: 1px solid rgba(108, 92, 231, 0.25);
    color: var(--accent-2);
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 24px;
    animation: fadeInDown 0.6s ease-out;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.15;
    margin-bottom: 16px;
    letter-spacing: -0.04em;
    animation: fadeInDown 0.6s ease-out 0.1s both;
}

.gradient-text {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.15rem;
    color: var(--text-secondary);
    line-height: 1.6;
    max-width: 500px;
    margin-bottom: 40px;
    animation: fadeInDown 0.6s ease-out 0.2s both;
}

/* === Shortener Card === */
.shortener-card {
    width: 100%;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 8px;
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow-glow);
    animation: fadeInUp 0.6s ease-out 0.3s both;
    position: relative;
}

.input-group {
    display: flex;
    align-items: center;
    background: rgba(255, 255, 255, 0.04);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(255, 255, 255, 0.06);
    transition: var(--transition);
}

.input-group:focus-within {
    border-color: rgba(108, 92, 231, 0.4);
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.1);
}

.input-icon {
    padding: 0 16px;
    color: var(--text-secondary);
    font-size: 1.1rem;
}

#url-input {
    flex: 1;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    padding: 16px 0;
}

#url-input::placeholder {
    color: var(--text-secondary);
    opacity: 0.7;
}

.shorten-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    margin: 4px;
    border: none;
    border-radius: var(--radius-sm);
    background: var(--gradient-btn);
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.shorten-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 8px 25px rgba(108, 92, 231, 0.4);
}

.shorten-btn:active {
    transform: translateY(0);
}

/* === Result Area === */
.result-area {
    display: none;
    align-items: center;
    justify-content: space-between;
    margin-top: 8px;
    padding: 16px 20px;
    background: rgba(34, 197, 94, 0.06);
    border: 1px solid rgba(34, 197, 94, 0.15);
    border-radius: var(--radius-sm);
    animation: fadeInUp 0.4s ease-out;
}

.result-area.visible {
    display: flex;
}

.result-content {
    display: flex;
    align-items: center;
    gap: 14px;
    min-width: 0;
}

.result-icon {
    color: var(--success);
    font-size: 1.4rem;
    flex-shrink: 0;
}

.result-info {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    min-width: 0;
}

.result-label {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-secondary);
    margin-bottom: 2px;
}

.short-url {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--accent-3);
    text-decoration: none;
    word-break: break-all;
    transition: var(--transition);
}

.short-url:hover {
    color: #7dd3fc;
}

.copy-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.06);
    color: var(--text-primary);
    font-size: 0.9rem;
    font-weight: 500;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
    flex-shrink: 0;
}

.copy-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.2);
}

.copy-btn.copied {
    background: rgba(34, 197, 94, 0.15);
    border-color: rgba(34, 197, 94, 0.3);
    color: var(--success);
}

/* Error State */
.error-area {
    background: rgba(239, 68, 68, 0.06) !important;
    border-color: rgba(239, 68, 68, 0.2) !important;
}

.error-icon {
    color: #ef4444 !important;
}

.error-text {
    color: #fca5a5;
    font-size: 0.95rem;
    word-break: break-all;
}

/* === Toast === */
.toast {
    position: absolute;
    bottom: -50px;
    left: 50%;
    transform: translateX(-50%) translateY(10px);
    background: var(--success);
    color: #fff;
    padding: 10px 20px;
    border-radius: 100px;
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 8px;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
    box-shadow: 0 8px 30px rgba(34, 197, 94, 0.3);
}

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

/* === Features === */
.features {
    display: flex;
    gap: 40px;
    margin-top: 50px;
    animation: fadeInUp 0.6s ease-out 0.5s both;
}

.feature {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.feature-icon {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.9rem;
    color: var(--accent-2);
}

/* === Footer === */
.footer {
    padding: 30px 40px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* === Animations === */
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

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

/* === Responsive === */
@media (max-width: 640px) {
    .hero h1 {
        font-size: 2.4rem;
    }
    .hero-desc {
        font-size: 1rem;
    }
    .input-group {
        flex-direction: column;
        align-items: stretch;
    }
    .input-icon {
        display: none;
    }
    #url-input {
        padding: 16px;
    }
    .shorten-btn {
        justify-content: center;
        margin: 4px;
        padding: 14px;
    }
    .result-area {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
    .result-content {
        flex-direction: column;
    }
    .result-info {
        align-items: center;
    }
    .copy-btn {
        width: 100%;
        justify-content: center;
    }
    .features {
        flex-direction: column;
        gap: 16px;
        align-items: center;
    }
    .header {
        padding: 16px 20px;
    }
}