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

:root {
    --primary-black: #0a0a0a;
    --secondary-black: #1a1a1a;
    --dark-gray: #2d2d2d;
    --accent-yellow: #FFD700;
    --bright-yellow: #FFED4E;
    --dark-yellow: #B8960A;
    --line-green: #06C755;
    --line-green-dark: #05B04C;
    --line-green-light: #07E863;
    --text-white: #ffffff;
    --text-gray: #b8b8b8;
}

body {
    font-family: 'Kanit', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(135deg, var(--primary-black) 0%, var(--secondary-black) 50%, var(--primary-black) 100%);
    min-height: 100vh;
    color: var(--text-white);
    overflow-x: hidden;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 30%, rgba(255, 215, 0, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(255, 237, 78, 0.06) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

.container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 20px;
    position: relative;
}

/* Animated background elements */
.container::before {
    content: '';
    position: fixed;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 215, 0, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    animation: backgroundMove 20s linear infinite;
    z-index: 0;
}

@keyframes backgroundMove {
    0% {
        transform: translate(0, 0);
    }

    100% {
        transform: translate(50px, 50px);
    }
}

.content {
    position: relative;
    z-index: 1;
    max-width: 500px;
    margin: 0 auto;
    width: 100%;
    padding: 40px 0;
}

/* Icon Wrapper */
.icon-wrapper {
    display: flex;
    justify-content: center;
    margin-bottom: 30px;
    animation: fadeInDown 0.8s ease-out;
}

.line-icon {
    width: 90px;
    height: 90px;
    background: linear-gradient(135deg, var(--accent-yellow) 0%, var(--bright-yellow) 100%);
    border-radius: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 15px 50px rgba(255, 215, 0, 0.4),
        0 5px 20px rgba(255, 237, 78, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
    animation: iconFloat 3s ease-in-out infinite;
    position: relative;
    border: 2px solid rgba(255, 237, 78, 0.5);
}

.line-icon::before {
    content: '';
    position: absolute;
    inset: -4px;
    background: linear-gradient(135deg, var(--accent-yellow), var(--bright-yellow));
    border-radius: 30px;
    z-index: -1;
    opacity: 0.4;
    filter: blur(15px);
    animation: glowPulse 2s ease-in-out infinite;
}

.line-icon svg {
    width: 55px;
    height: 55px;
    color: var(--primary-black);
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

@keyframes iconFloat {

    0%,
    100% {
        transform: translateY(0) scale(1);
    }

    50% {
        transform: translateY(-10px) scale(1.03);
    }
}

@keyframes glowPulse {

    0%,
    100% {
        opacity: 0.4;
        filter: blur(15px);
    }

    50% {
        opacity: 0.6;
        filter: blur(20px);
    }
}

/* Title Section */
.title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 12px;
    background: linear-gradient(135deg, var(--text-white), var(--accent-yellow));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}

.subtitle {
    font-size: 1rem;
    font-weight: 300;
    text-align: center;
    color: var(--text-gray);
    margin-bottom: 40px;
    animation: fadeInUp 0.8s ease-out 0.3s both;
}

/* LINE ID Box */
.line-id-box {
    background: rgba(255, 215, 0, 0.1);
    border: 2px solid var(--accent-yellow);
    border-radius: 16px;
    padding: 20px;
    text-align: center;
    margin-bottom: 30px;
    animation: fadeInUp 0.8s ease-out 0.4s both;
    position: relative;
    overflow: hidden;
}

.line-id-box::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(255, 215, 0, 0.1), transparent);
    animation: shimmer 3s infinite;
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%) translateY(-100%) rotate(45deg);
    }

    100% {
        transform: translateX(100%) translateY(100%) rotate(45deg);
    }
}

.line-id-label {
    display: block;
    font-size: 0.9rem;
    color: var(--text-gray);
    margin-bottom: 8px;
    position: relative;
}

.line-id {
    display: block;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent-yellow);
    letter-spacing: 1px;
    position: relative;
}

/* Add LINE Button */
.add-line-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 14px;
    width: 100%;
    padding: 20px 36px;
    background: linear-gradient(135deg, var(--line-green) 0%, var(--line-green-light) 100%);
    color: var(--text-white);
    font-size: 1.3rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 18px;
    box-shadow: 0 10px 40px rgba(6, 199, 85, 0.5),
        0 4px 15px rgba(7, 232, 99, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.2);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    animation: fadeInUp 0.8s ease-out 0.5s both;
    position: relative;
    overflow: hidden;
    border: 2px solid rgba(7, 232, 99, 0.3);
}

.add-line-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.25);
    transform: translate(-50%, -50%);
    transition: width 0.6s ease, height 0.6s ease;
}

.add-line-btn::after {
    content: '';
    position: absolute;
    inset: -3px;
    background: linear-gradient(135deg, var(--line-green), var(--line-green-light));
    border-radius: 20px;
    z-index: -1;
    opacity: 0.6;
    filter: blur(20px);
    animation: buttonGlow 2s ease-in-out infinite;
}

@keyframes buttonGlow {

    0%,
    100% {
        opacity: 0.5;
        filter: blur(20px);
    }

    50% {
        opacity: 0.8;
        filter: blur(25px);
    }
}

.add-line-btn:hover::before {
    width: 350px;
    height: 350px;
}

.add-line-btn:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 15px 50px rgba(6, 199, 85, 0.6),
        0 8px 25px rgba(7, 232, 99, 0.4),
        inset 0 1px 0 rgba(255, 255, 255, 0.3);
    border-color: rgba(7, 232, 99, 0.5);
}

.add-line-btn:active {
    transform: translateY(-1px) scale(1);
    box-shadow: 0 6px 20px rgba(6, 199, 85, 0.4),
        0 2px 10px rgba(7, 232, 99, 0.3);
}

.btn-icon {
    width: 32px;
    height: 32px;
    position: relative;
    z-index: 1;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

.btn-text {
    position: relative;
    z-index: 1;
}

/* QR Section */
.qr-section {
    margin-top: 50px;
    text-align: center;
    animation: fadeInUp 0.8s ease-out 0.6s both;
}

.qr-text {
    font-size: 0.95rem;
    color: var(--text-gray);
    margin-bottom: 20px;
    position: relative;
    display: inline-block;
}

.qr-text::before,
.qr-text::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 40px;
    height: 1px;
    background: var(--accent-yellow);
}

.qr-text::before {
    right: calc(100% + 15px);
}

.qr-text::after {
    left: calc(100% + 15px);
}

.qr-placeholder {
    width: 180px;
    height: 180px;
    margin: 0 auto 15px;
    background: var(--text-white);
    border-radius: 16px;
    padding: 15px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease;
}

.qr-placeholder:hover {
    transform: scale(1.05);
}

.qr-placeholder svg {
    width: 100%;
    height: 100%;
}

.qr-hint {
    font-size: 0.85rem;
    color: var(--text-gray);
    font-weight: 300;
}

/* Features */
.features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    margin-top: 50px;
    animation: fadeInUp 0.8s ease-out 0.7s both;
}

.feature-item {
    background: rgba(255, 215, 0, 0.05);
    border: 1px solid rgba(255, 215, 0, 0.2);
    border-radius: 12px;
    padding: 20px 10px;
    text-align: center;
    transition: all 0.3s ease;
}

.feature-item:hover {
    background: rgba(255, 215, 0, 0.1);
    border-color: var(--accent-yellow);
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 2rem;
    margin-bottom: 10px;
    filter: grayscale(0.3);
}

.feature-text {
    font-size: 0.85rem;
    color: var(--text-gray);
    font-weight: 400;
}

/* Footer */
.footer {
    text-align: center;
    padding: 20px 0;
    color: var(--text-gray);
    font-size: 0.85rem;
    position: relative;
    z-index: 1;
    animation: fadeIn 0.8s ease-out 0.8s both;
}

/* Animations */
@keyframes fadeInDown {
    from {
        opacity: 0;
        transform: translateY(-30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 480px) {
    .title {
        font-size: 1.75rem;
    }

    .subtitle {
        font-size: 0.9rem;
    }

    .line-id {
        font-size: 1.3rem;
    }

    .add-line-btn {
        font-size: 1.1rem;
        padding: 16px 28px;
    }

    .features {
        gap: 10px;
    }

    .feature-item {
        padding: 15px 8px;
    }

    .feature-icon {
        font-size: 1.5rem;
    }

    .feature-text {
        font-size: 0.75rem;
    }

    .qr-placeholder {
        width: 150px;
        height: 150px;
    }
}

@media (max-width: 360px) {
    .content {
        padding: 20px 0;
    }

    .line-icon {
        width: 70px;
        height: 70px;
    }

    .line-icon svg {
        width: 40px;
        height: 40px;
    }

    .title {
        font-size: 1.5rem;
    }
}