:root {
    --bg-color: #1a1a1a;
    --container-bg: #2c2c2c;
    --text-color: #f0f0f0;
    --title-color: #ffa726;
    --circle-bg: #424242;
    --circle-text: #fff;
    --btn-bg: #ffa726;
    --btn-color: #1a1a1a;
    --btn-hover-bg: #ffb74d;
    --btn-shadow: rgba(255, 167, 38, 0.5);
    --btn-hover-shadow: rgba(255, 183, 77, 0.8);
    --toggle-bg: #444;
    --toggle-color: #f0f0f0;
}

[data-theme="light"] {
    --bg-color: #f0f0f0;
    --container-bg: #ffffff;
    --text-color: #1a1a1a;
    --title-color: #e65100;
    --circle-bg: #e0e0e0;
    --circle-text: #1a1a1a;
    --btn-bg: #e65100;
    --btn-color: #ffffff;
    --btn-hover-bg: #ff6d00;
    --btn-shadow: rgba(230, 81, 0, 0.4);
    --btn-hover-shadow: rgba(255, 109, 0, 0.7);
    --toggle-bg: #e0e0e0;
    --toggle-color: #1a1a1a;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-image: url("data:image/svg+xml,%3Csvg width='42' height='44' viewBox='0 0 42 44' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23888888' fill-opacity='0.15'%3E%3Cpath d='M0 0h42v44H0V0zm1 1h40v20H1V1zM0 23h20v20H0V23zm22 0h20v20H22V23z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    transition: background-color 0.3s ease, color 0.3s ease;
}

#theme-toggle {
    position: fixed;
    top: 1.2rem;
    right: 1.2rem;
    background-color: var(--toggle-bg);
    color: var(--toggle-color);
    border: none;
    border-radius: 50%;
    width: 44px;
    height: 44px;
    font-size: 1.3rem;
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

#theme-toggle:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
}

.container {
    background-color: var(--container-bg);
    padding: 2rem;
    border-radius: 15px;
    box-shadow:
        0 4px 8px rgba(0, 0, 0, 0.2),
        0 10px 20px rgba(0, 0, 0, 0.3);
    text-align: center;
    transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

h1 {
    margin-top: 0;
    font-size: 2.5rem;
    color: var(--title-color);
    transition: color 0.3s ease;
}

.numbers-container {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 2rem 0;
}

.number-circle {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background-color: var(--circle-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--circle-text);
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.3);
    transition: background-color 0.3s ease, color 0.3s ease;
}

#generate-btn {
    background-color: var(--btn-bg);
    color: var(--btn-color);
    border: none;
    padding: 1rem 2rem;
    font-size: 1.2rem;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 0 15px var(--btn-shadow);
}

#generate-btn:hover,
#generate-btn:focus {
    background-color: var(--btn-hover-bg);
    box-shadow: 0 0 25px var(--btn-hover-shadow);
    transform: translateY(-2px);
}

/* Contact Form */
.contact-section {
    width: 100%;
    display: flex;
    justify-content: center;
    padding: 3rem 1rem 4rem;
}

.contact-container {
    background-color: var(--container-bg);
    padding: 2rem;
    border-radius: 15px;
    box-shadow:
        0 4px 8px rgba(0, 0, 0, 0.2),
        0 10px 20px rgba(0, 0, 0, 0.3);
    width: 100%;
    max-width: 480px;
    transition: background-color 0.3s ease;
}

.contact-container h2 {
    margin-top: 0;
    font-size: 1.8rem;
    color: var(--title-color);
    text-align: center;
    transition: color 0.3s ease;
}

.contact-desc {
    text-align: center;
    font-size: 0.95rem;
    opacity: 0.7;
    margin-bottom: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    margin-bottom: 1.2rem;
}

.form-group label {
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.4rem;
    color: var(--text-color);
}

.form-group input,
.form-group textarea {
    background-color: var(--circle-bg);
    color: var(--text-color);
    border: 1px solid transparent;
    border-radius: 8px;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    font-family: inherit;
    outline: none;
    transition: all 0.3s ease;
    resize: none;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    opacity: 0.5;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: var(--btn-bg);
    box-shadow: 0 0 0 3px var(--btn-shadow);
}

.submit-btn {
    width: 100%;
    background-color: var(--btn-bg);
    color: var(--btn-color);
    border: none;
    padding: 0.9rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 0 15px var(--btn-shadow);
    margin-top: 0.4rem;
}

.submit-btn:hover {
    background-color: var(--btn-hover-bg);
    box-shadow: 0 0 25px var(--btn-hover-shadow);
    transform: translateY(-2px);
}

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

#form-status {
    text-align: center;
    margin-top: 0.8rem;
    font-size: 0.95rem;
    min-height: 1.2rem;
}