:root {
    --microsoft-blue: #0078D4;
    --microsoft-dark-blue: #005A9E;
    --success-green: #107C10;
    --error-red: #D13438;
    --text-primary: #323130;
    --text-secondary: #605E5C;
    --background: #F3F2F1;
    --card-background: #FFFFFF;
    --shadow: rgba(0, 0, 0, 0.1);
    --festive-red: #C50F1F;
    --festive-green: #107C10;
    --festive-gold: #FFB900;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    position: relative;
    overflow-x: hidden;
}

/* Snowflake Animation */
.snowflakes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
}

.snowflake {
    position: absolute;
    top: -10%;
    color: white;
    font-size: 1.5em;
    opacity: 0.8;
    animation: fall linear infinite;
    text-shadow: 0 0 5px rgba(255, 255, 255, 0.5);
}

.snowflake:nth-child(1) { left: 10%; animation-duration: 10s; animation-delay: 0s; }
.snowflake:nth-child(2) { left: 20%; animation-duration: 12s; animation-delay: 2s; }
.snowflake:nth-child(3) { left: 30%; animation-duration: 9s; animation-delay: 4s; }
.snowflake:nth-child(4) { left: 40%; animation-duration: 11s; animation-delay: 1s; }
.snowflake:nth-child(5) { left: 50%; animation-duration: 13s; animation-delay: 3s; }
.snowflake:nth-child(6) { left: 60%; animation-duration: 10s; animation-delay: 5s; }
.snowflake:nth-child(7) { left: 70%; animation-duration: 12s; animation-delay: 2.5s; }
.snowflake:nth-child(8) { left: 80%; animation-duration: 11s; animation-delay: 4.5s; }

@keyframes fall {
    to {
        transform: translateY(105vh) rotate(360deg);
    }
}

/* Main Container */
.container {
    max-width: 600px;
    width: 100%;
    position: relative;
    z-index: 2;
}

/* Header */
header {
    text-align: center;
    margin-bottom: 2rem;
}

.logo-section h1 {
    color: white;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2), 0 0 10px rgba(255, 255, 255, 0.5);
    }
    to {
        text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2), 0 0 20px rgba(255, 255, 255, 0.8), 0 0 30px rgba(255, 215, 0, 0.6);
    }
}

.subtitle {
    color: white;
    font-size: 1.1rem;
    font-weight: 500;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.2);
}

/* Cards */
.card, .info-card {
    background: var(--card-background);
    border-radius: 12px;
    padding: 2rem;
    box-shadow: 0 8px 32px var(--shadow);
    margin-bottom: 1.5rem;
    backdrop-filter: blur(10px);
}

.card h2 {
    color: var(--microsoft-blue);
    font-size: 1.75rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

.description {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

/* Deadline Banner */
.deadline-banner {
    background: linear-gradient(135deg, #FFB900 0%, #FF8C00 100%);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    text-align: center;
    font-size: 1.05rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 4px 12px rgba(255, 140, 0, 0.3);
    animation: pulse 2s ease-in-out infinite;
}

.deadline-banner strong {
    font-weight: 700;
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
        box-shadow: 0 4px 12px rgba(255, 140, 0, 0.3);
    }
    50% {
        transform: scale(1.02);
        box-shadow: 0 6px 16px rgba(255, 140, 0, 0.5);
    }
}

/* Form */
.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    color: var(--text-primary);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

input[type="email"] {
    width: 100%;
    padding: 0.875rem;
    border: 2px solid #E1DFDD;
    border-radius: 6px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s ease;
}

input[type="email"]:focus {
    outline: none;
    border-color: var(--microsoft-blue);
    box-shadow: 0 0 0 3px rgba(0, 120, 212, 0.1);
}

input[type="email"]:invalid:not(:placeholder-shown) {
    border-color: var(--error-red);
}

/* Submit Button */
.submit-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--microsoft-blue) 0%, var(--microsoft-dark-blue) 100%);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    box-shadow: 0 4px 12px rgba(0, 120, 212, 0.3);
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(0, 120, 212, 0.4);
}

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

.submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-icon {
    font-size: 1.3rem;
}

/* Message */
.message {
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 6px;
    font-weight: 500;
    text-align: center;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.message.hidden {
    display: none;
}

.message.success {
    background: #DFF6DD;
    color: var(--success-green);
    border: 1px solid var(--success-green);
}

.message.error {
    background: #FDE7E9;
    color: var(--error-red);
    border: 1px solid var(--error-red);
}

/* Info Card */
.info-card {
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, rgba(255, 255, 255, 0.9) 100%);
}

.info-card h3 {
    color: var(--festive-green);
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.info-card ul {
    list-style: none;
}

.info-card li {
    color: var(--text-secondary);
    padding: 0.5rem 0;
    border-bottom: 1px solid #E1DFDD;
}

.info-card li:last-child {
    border-bottom: none;
}

.info-card strong {
    color: var(--text-primary);
}

/* Footer */
footer {
    text-align: center;
    padding: 1rem;
    color: white;
    font-size: 0.9rem;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.2);
}

/* Responsive Design */
@media (max-width: 640px) {
    .logo-section h1 {
        font-size: 2rem;
    }

    .card, .info-card {
        padding: 1.5rem;
    }

    .card h2 {
        font-size: 1.5rem;
    }
}